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Nachhaltige und zukunftsfähige Mobilität in Städten kann langfristig nur durch die aktive Partizipation ihrer Bürger und Institutionen erreicht werden. Betriebliches Mobilitätsmanagement (BMM) kann dabei einen positiven Beitrag im Hinblick auf Umwelt, Gesundheit und Kosten leisten. Die vorliegende Arbeit beschäftigt sich mit der Wahrnehmung gesundheitlicher und finanzieller Wertschöpfungsaspekte des BMM. Im Rahmen des Forschungsprojekts Betriebe lösen Verkehrsprobleme werden Mobilitätsverhalten und Maßnahmen der Betrieblichen Gesundheitsförderung (BFG) in Bonner Betrieben untersucht. Folgenden Aspekten wird besondere Beachtung geschenkt: Bedeutung Betrieblicher Gesundheitsförderung in Bonner Betrieben, Mobilitätsverhalten von Arbeitnehmern auf dem Weg zur Dienststelle, Wahrnehmung eines unmittelbaren Zusammenhangs zwischen körperlicher Aktivität und Gesundheit bzw. krankheitsbedingter Kosten und Umsatzeinbußen durch Bewegungsmangel. Die Analyse resultiert auf der Basis einer schriftlichen Befragung von 178 Unternehmen, einer Online-Umfrage von 1.341 Mitarbeitern aus 14 Unternehmen sowie auf persönlichen Interviews mit 22 Betriebsleitern bzw. Mobilitäts- und Gesundheitsbeauftragten. Die Ergebnisse der Studie machen sowohl Handlungsbedarf als auch Optimierungspotentiale im Bereich BMM auf Betriebsseite deutlich. Kostensimulationen zeigen darüber hinaus auf, dass durch die Implementierung von BGF-Maßnahmen, explizit der Förderung von Bewegung, auf betriebs- und volkswirtschaftlicher Seite beachtliche Kosten im Gesundheitsbereich eingespart sowie höhere Gewinne im Unternehmen erzielt werden können.
In January 2015, German trade and industry announced to support the national animal welfare initiative "Initiative Tierwohl" (ITW) which stands for a more sustainable and animal-friendly meat production. A web content analysis shows that the ITW initiative has been widely picked up and discussed by online media and that user comments are quite heterogeneous. The current study identifies different types of consumers through factor and cluster analysis and is based on an online survey as well as face-to-face interviews. According to our results, the identified consumer groups demonstrate a rather passive comment behaviour on the internet. In fact, the internet was hardly mentioned as an information source for meat production; consumers more frequently referred to brochures, leaflets and personal contacts with sales personnel.
Although much effort is made to prevent risks arising from food, food-borne diseases are an ever-present threat to the consumers’ health. The consumption of fresh food that is contaminated with pathogens like fungi, viruses or bacteria can cause food poisoning that leads to severe health damages or even death. The outbreak of Shiga Toxin-producing enterohemorrhagic E. coli (EHEC) in Germany and neighbouring countries in 2011 has shown this dramatically. Nearly 4.000 people were reported of being affected and more than 50 people died during the so called EHEC-crisis. As a result the consumers’ trust in the safety of fruits and vegetables decreased sharply.
Seit Sokrates bildet die Frage „Was macht ein glückliches Leben aus?“ den Ausgangspunkt der Entwicklung einer Vielfalt von Wohlbefindenstheorien. Den Kern dieses Aufsatzes bildet die Erörterung der Fragen, inwieweit das Konzept der empirischen Lebenszufriedenheit und die dadurch gewonnenen Korrelate einen Beitrag zur Beantwortung dieser Frage leisten und ob diese Antworten eine Wohlbefindenstheorie begründen können, welche die philosophische Theorie mit empirischen Ergebnissen verknüpft.
Im Zentrum dieses Aufsatzes steht eine Diskussion der wichtigsten Wohlbefindenstheorien, ihrer Qualitäten, Gemeinsamkeiten und Unterschiede. Einen Schwerpunkt bildet die Theorie der subjektiven Lebenszufriedenheit. Ich diskutiere Stärken und Schwächen des Konzeptes und stelle die wichtigsten Ergebnisse der empirischen Lebenszufriedenheitsforschung in einem Überblick dar.
Im Ergebnis argumentiere ich, dass die Resultate der empirischen Forschung als Grundlage einer subjektiv-objektiven Wohlbefindenstheorie dienen können. Qualitativ hochwertige zwischenmenschliche Beziehungen, ein gesunder Lebensstil, eine ausgewogene Work-Life-Balance, der Einsatz für Andere, das Verfolgen von Lebenszielen und persönlichen Interessen bilden die Grundlage einer Wohlbefindenstheorie, die sich auf empirische Lebenszufriedenheitsforschung stützt.
Das Forschungsprojekt beruht auf zwei Elementen: Die erste Untersuchung, ein Verhaltensexperiment mit 35 Studierenden der Hochschule Bonn-Rhein-Sieg, erforschte den Einfluss von Gruppengröße (Zuschauereffekt) und dargebotenen Informationen zu Verantwortungsdiffusion (Priming) auf nachhaltiges Verhalten. Mithilfe eines zweiten Online-Experiments folgte eine Erhebung zum Einfluss von wahrgenommener persönlicher Bedrohung auf die Bereitschaft zu nachhaltigem Verhalten (N = 72). Die Ergebnisse des ersten Experimentes zeigen einen schwachen, statistisch nicht signifikanten Einfluss der Gruppengröße sowie einen, z.T. statistisch signifikanten, Einfluss der dargebotenen Informationen zu Verantwortungsdiffusion auf das gemessene nachhaltige Verhalten. Bequemlichkeit sowie monetärer Aufwand stellen mit Abstand die größten Hindernisse für nachhaltiges Verhalten dar, während die Beeinflussung durch andere und das Ziel des Umweltschutzes als positive Argumente für nachhaltiges Verhalten genannt wurden. In der Folgestudie konnte ein statistisch signifikanter kausaler Zusammenhang zwischen der wahrgenommenen persönlichen Bedrohung durch die aktuelle Umwelt- und Klimasituation und der Bereitschaft zu nachhaltigem Verhalten nachgewiesen werden. Alle Resultate zu Verhaltensintentionen zeigten insgesamt eine hohe Bereitschaft der Probanden zu nachhaltigem Verhalten.
Cultivation of perennials such as Miscanthus x giganteus Greef et Deuter (Mis) combines the provision of ecosystem services and the generation of additional carbon sources for farming. The potential of Mis based fertilisers, regarding immobilisation of inorganic nitrogen (N) and build-up of soil organic matter (SOM), was tested in a field trial. Therefore, a crop rotation of winter barley (Hordeum vulgare L.), mustard (Sinapis alba L.) as catch crop, sugar beet (Beta vulgaris L.) and winter wheat (Triticum aestivum L.) was set up. The tested treatments were a mixture of Cattle Slurry (CS) and Mis, a mixture of CS and Wheat Straw (CS–WS), Cattle Manure (CM) from Mis shredded bedding, CM from WS shredded bedding, a pure CS, Urea Ammonium Nitrate (UAN) and a treatment without any N applied (NoN). When the carbon-rich fertilisers (both mixtures and manures) were applied to cereals, they led to a slight N immobilisation compared to pure CS, whereas differences were mostly not significant. Furthermore, Mis fertilisers were at least as efficient as WS-based organic fertilisers in inducing a contribution of SOM build-up and in reducing inorganic N before winter and thus preventing N losses, whereas differences were mostly not significant.
Green infrastructure has been widely recognized for the benefits to human health and biodiversity conservation. However, knowledge of the qualities and requirements of such spaces and structures for the effective delivery of the range of ecosystem services expected is still limited, as well as the identification of trade-offs between services. In this study, we apply the One Health approach in the context of green spaces to investigate how urban park characteristics affect human mental health and wildlife support outcomes and identify synergies and trade-offs between these dimensions. Here we show that perceived restorativeness of park users varies significantly across sites and is mainly affected by safety and naturalness perceptions. In turn, these perceptions are driven by objective indicators of quality, such as maintenance of facilities and vegetation structure, and subjective estimations of biodiversity levels. The presence of water bodies benefited both mental health and wildlife. However, high tree canopy coverage provided greater restoration potential whereas a certain level of habitat heterogeneity was important to support a wider range of bird species requirements. To reconcile human and wildlife needs in green spaces, cities should strategically implement a heterogeneous green infrastructure network that considers trade-offs and maximizes synergies between these dimensions.
Agricultural activities within the city boundaries have a long history in both developed and developing countries. Especially in developing countries these activities contribute to food security and the mitigation of malnutrition (food grown for home consumption). They generate additional income and contribute to recreation, environmental health as well as social interaction. In this paper, a broad approach of Urban AgriCulture is used, which includes the production of crops in urban and peri-urban areas and ranges in developed countries from allotment gardens (Schrebergarten) over community gardens (Urban Gardening) to semi-entrepreneurial self-harvest farms and fully commercialized agriculture (Urban Farming). Citizens seek to make a shift from traditional to new (sustainable) forms of food supply. From this evolves a demand for urban spaces that can be used agriculturally. The way how these citizens’ initiatives can be supported and their contribution to a resilient and sustainable urban food system increasingly attracts attention. This paper presents an empirical case study on Urban AgriCulture initiatives in the Bonn-Rhein-Sieg region (Germany). Urban AgriCulture is still a niche movement with the potential to contribute more significantly to urban development and constitute a pillar of urban quality of life.
Agricultural activities within city boundaries have a long history in both developed and developing countries. In this paper, a broad approach to Urban AgriCulture (UAC) is used, one that includes the production of crops in urban and peri-urban areas and ranges in developed countries from allotment gardens over community gardens to semi-entrepreneurial self-harvest farms and fully commercialized agriculture. With an empirical case study on UAC Initiatives in the Bonn/Rhein-Sieg region this work fills a gap since the lack of comprehensive and comparative studies on urban agriculture (UA) currently makes it difficult for researchers to identify the benefits of UA activities.
Political economic analyses of recent social protection reforms in Asian, African or Latin American countries have increased throughout the last few years. Yet, most contributions focus on one social protection mechanism only and do not provide a comparative approach across policy areas. In addition, most studies are empirical studies, with no or very limited theoretical linkages. The paper aims to explain multiple trajectories of social protection reform processes looking at cash transfers and social health protection policies in Kenya. It develops a taxonomy and suggest a conceptual framework to assess and explain reform dynamics across different social protection pillars. In order to allow for a more differentiated typology and enable us to understand different reform dynamics, the article uses the approach on gradual institutional change. While existing approaches to institutional change mostly focus on institutional change prompted by exogenous shocks or environmental shifts, this approach takes account of both, exogenous and endogenous sources of change.
Over the past two decades many governments of low and middle income countries have started to introduce social protection measures or to extend the coverage and improve the functioning of public social protection systems. These reforms are a "global phenomenon" and can be observed in many African, Asian and Latin American countries. This paper focuses on international determinants for policy change within social protection by assessing the state of the art of both policy diffusion and policy transfer studies. Empirical studies of policy transfer and diffusion in the field of social protection are furthermore assessed in light of the theoretical background.
In recent years, there has been a growing interest in the start-up scene in sub-Saharan Africa. "Silicon Savannah" is today widely used to describe the thriving IT industry in and around Nairobi. Kenya's geographical advantage, its favorable economic reforms, and mature start-up ecosystem makes it stands out positively. Since a lot of hype exists around the start-up scene many investors are drawn to it, but in reality very few start-ups are investment-ready. The increasing start-up requirements and needs force incubators to diversify their offer. In contrast, to traditional incubators, an Innovation Hub (Hub) is characterized based on the concept of open innovation and collaboration. A Hub nurtures an enabling environment where a community of entrepreneurs can grow. At the same time, it serves as a nexus point for the local start-up community, investors, academia, technology companies and the wider private sector. It aims to create a structure where people serendipitously interact with others that they would not typically meet. Considering the great interest for and the large amounts of money invested in Hubs by governments, universities, private companies and other interested parties, not only researchers have been raising the question of the actual benefit of Hubs. This research study aims to investigate to what extent the support offered by the Hubs is tackling the challenges faced by start-ups in Nairobi, Kenya. The analysis can serve as a basis for identifying strength and weaknesses in the Hub models.
The Poverty Reduction Effect of Social Protection: The Pros and Cons of a Multidisciplinary Approach
(2022)
There is a growing body of knowledge on the complex effects of social protection on poverty in Africa. This article explores the pros and cons of a multidisciplinary approach to studying social protection policies. Our research aimed at studying the interaction between cash transfers and social health protection policies in terms of their impact on inclusive growth in Ghana and Kenya. Also, it explored the policy reform context over time to unravel programme dynamics and outcomes. The analysis combined econometric and qualitative impact assessments with national- and local-level political economic analyses. In particular, dynamic effects and improved understanding of processes are well captured by this approach, thus, pushing the understanding of implementation challenges over and beyond a ‘technological fix,’ as has been argued before by Niño-Zarazúa et al. (World Dev 40:163–176, 2012), However, multidisciplinary research puts considerable demands on data and data handling. Finally, some poverty reduction effects play out over a longer time, requiring longitudinal consistent data that is still scarce.
The article contributes to understanding the political economy of implementation of social protection programmes at local level. Current debates are dominated by technocratic arguments, emphasizing the lack of financial resources, technology or skills as major barriers for effective implementation. Describing how chiefs, assistant-chiefs and community elders are routinely at the centre stage of core implementation processes, including targeting, enrolment, delivery, monitoring, awareness and information, data collection or grievance and redress, this study on Kenya argues for the need to look more closely into the local political economy as an important mediating arena for implementing social policies. Implementation is heavily contingent upon the local social, political and institutional context that influences and shapes its outcomes. These processes are ambivalent involving multiple forms of interactions between ‘formal’ and ‘informal’ institutional structures, which may support initial policy objectives or induce policy outcomes substantially diverging from intended policy objectives.
The paper contributes to the debate on the political economy of implementation of propoor social policy. It argues for a broadening of the debate, which is dominated by technocratic arguments, emphasizing the lack of financial resources, technology or skills as the major barriers for effective implementation. Describing the dynamic interplay of ‘formal’ operational programme structures and ‘informal’ traditional institutions in delivering the CT-OVC – the largest and oldest cash transfer programme in Kenya – it argues for the need to look more closely into the local political economy as an important mediating arena for implementing social policies. Implementation is heavily contingent upon the local social, political and institutional context that influences and shapes its outcomes. These processes are highly dynamic and ambivalent evolving between ‘formal’ and ‘informal’ structures and institutions. They may change over time and place, challenging the implicit assumption that programmes are evenly implemented across geographic and political entities.
In the last two decades, studies that analyse the political economy of sustainable energy transitions have increasingly become available. Yet very few attempts have been made to synthesize the factors discussed in the growing literature. This paper reviews the extant empirical literature on the political economy of sustainable energy transitions. Using a well-defined search strategy, a total of 36 empirical contributions covering the period 2008 to 2022 are reviewed full text. Overall, the findings highlight the role of vested interest, advocacy coalitions and green constituencies, path dependency, external shocks, policy and institutional environment, political institutions and fossil fuel resource endowments as major political economy factors influencing sustainable energy transitions across both high income countries, and low and middle income countries. In addition, the paper highlights and discusses some critical knowledge gaps in the existing literature and provides suggestions for a future research agenda.
The phenomenon of the deviation between purchase attitudes and actual buying behaviour of responsible consumers is called the attitude-behaviour gap. It is influenced by individual, social and situational factors. The main purchasing barriers for sustainable (organic) food are price, lack of immediate availability, sensory criteria, lack or overload of information as well as the low-involvement feature of food products in conjunction with well-established consumption routines, lack of transparency and trust towards labels and certifications. The last three barriers are mainly of a psychological nature. Especially the low-involvement feature of food products due to daily purchase routines and relatively low prices tends to result in fast, automatic and subconscious decisions based on a so-called human mental system 1, derived from Daniel Kahneman’s (Nobel-Prize laureate in Behavioural Economics) model in behavioural psychology. In contrast, the human mental system 2 is especially important for the transformations of individual behaviour towards a more sustainable consumption. Decisions based on the human mental system 2 are slow, logical, rational, conscious and arduous. This so-called dual action model also influences the reliability of responses in consumer surveys. It seems that the consumer behaviour is the most unstable and unpredictable part of the entire supply chain and requires special attention. Concrete measures to influence consumer behaviour towards sustainable consumption are highly complex. Reviews of interdisciplinary research literature on behavioural psychology, behavioural economics and consumer behaviour and an empirical analysis of selected countries worldwide with a view to sustainable food are presented. The example of Denmark serves as a ‘best practice’ case study to illustrate how sustainable food consumption can be encouraged. It demonstrates that common efforts and a shared responsibility of consumers, business, interdisciplinary researchers, mass media and policy are needed. It takes pioneers of change who succeed in assembling a ‘critical mass’ willing to increase its ‘sustainable’ behaviour. Considering the strong psychological barriers of consumers and the continuing low market share of organic food, proactive policy measures would be conducive to foster the personal responsibility of the consumers and offer incentives towards a sustainable production. Also, further self-obligations of companies (Corporate Social Responsibility – CSR) as well as more transparency and simplification of reliable labels and certifications are needed to encourage the process towards a sustainable development.
In den Atmosphärenwissenschaften spielt die Strahlungsbilanz der Erde eine wichtige Rolle für unser Verständnis des Klimasystems. Hier liefern ausgereifte Satellitenprodukte dekadische Klimazeitreihen mit einer so hohen Genauigkeit, dass z.B. Änderungen im Zusammenhang mit dem Klimawandel detektiert werden können. Dies gilt insbesondere auch für die solaren Strahlungsflüsse an der Erdoberfläche. Beim Vergleich dieser Satellitenprodukte mit instantanen Beobachtungen der Strahlung am Erdboden sind jedoch oft erhebliche Abweichungen feststellbar, die hauptsächlich durch kleinskalige Variabilität in der räumlichen Struktur von Wolken und ihrer Strahlungswirkung verursacht werden. Hier ist auch zu bedenken, dass Bodenbeobachtungen fast einer Punktmessung entsprechen, während Satellitenpixel eine Fläche in der Größenordnung von Quadratkilometern abtasten.
This paper analyzes the complex effects and risks of social protection programmes in Ghana and Kenya on poor people’s human wellbeing, voice and empowerment and interactions with the social protection regulatory framework and policy instruments. For this purpose, it adopts a comprehensive Inclusive Development framework to systematically explore the complex effects of cash transfers and health insurance at the individual, household and community level. The findings highlight the positive provisionary and preventive effects of social protection, but also illustrate that the poorest are still excluded and that promotive effects, in the form of enhanced productivity, manifest themselves mainly for the people who are less resource poor. They can build more effectively upon an existing asset base, capabilities, power and social relations to counter the exclusionary mechanisms of the system, address inequity concerns and offset the transaction costs of accessing and benefitting from social protection. The inclusive development framework enables to lay these complex effects and interactions bear, and points to areas that require more longitudinal and mixed methodology research.
Social Insurance
(2018)
Extending coverage through contributory social insurance or other contributory programs is tempting for governments as a potential avenue for mobilizing new resources and creating new fiscal space. Such extension has clear limits, however: it applies only to those in the labor market who have employment status with high degree of formality and whose incomes are significantly above subsistence level and received regularly. It also requires administrative structures with capacity to regularly register incomes of those covered, and to collect contributions.
This chapter analyzes the potential of social insurance (also called contributory social protection) in the 16 Asian countries reviewed in this publication to fill the protection and coverage gaps in income security. It focuses on pensions, but also reviews other benefits temporarily replacing lost labor income due to events such as sickness, maternity, and unemployment. As current labor market structures largely determine the chances of extending coverage through these means, this chapter also examines their characteristics and analyzes coverage by the different forms of social insurance and assesses the potential for extension.
Social Assistance
(2018)
If the first Sustainable Development Goal (SDG) to “End poverty in all its forms everywhere” is to be taken seriously, most low- and middle-income countries face a huge challenge. An estimated 1 billion people have indeed escaped extreme poverty since the early 1990s, and the global poverty rate fell from 35% in 1990 to 10.7% in 2013, but the absolute number of people living below the international poverty line of $1.90 at purchasing power parity has hardly changed. Countries in Asia contributed greatly to the overall decline in poverty rates: from 2012 to 2013, over 100 million people in Asia left extreme poverty behind, notably in India, Indonesia, and the People’s Republic of China (PRC) (World Bank 2016). Yet the living standards of those still below that line have hardly improved (Ravallion 2016). The achievement of the first SDG requires additional efforts at global and national levels, particularly on policies that address chronic poverty traps and that improve the outcomes of poor and vulnerable populations.
Viele Bereiche des Wirtschaftslebens werden heute durch die Digitalisierung beeinflusst. Sowohl auf Grundlage neuer technischer Möglichkeiten und der damit einhergehenden Vernetzung, als auch mit einem Wandel im Konsumverhalten hat sich die Sharing Economy entwickelt. Auf dem Gebiet der urbanen Mobilität ergibt sich für Anbieter und Nachfrager eine Vielzahl neuer Möglichkeiten im Rahmen der Sharing Economy. Die Arbeit setzt sich sowohl mit den aktuellen Mobilitätstrends, als auch mit dem Wandel im Konsumverhalten auseinander. Im Fokus steht hierbei das Ridesourcing, also die entgeltlichen Personenbeförderung von privaten Fahrern mit eigenem Fahrzeug, bei der der Fahrgast das Fahrziel bestimmt und die Vorteile die ein Markteintritt dieser Anbieter mit sich bringt.
The cooperation between researchers and practitioners during the different stages of the research process is promoted as it can be of benefit to both society and research supporting processes of ‘transformation’. While acknowledging the important potential of research–practice–collaborations (RPCs), this paper reflects on RPCs from a political-economic perspective to also address potential unintended adverse effects on knowledge generation due to divergent interests, incomplete information or the unequal distribution of resources. Asymmetries between actors may induce distorted and biased knowledge and even help produce or exacerbate existing inequalities. Potential merits and limitations of RPCs, therefore, need to be gauged. Taking RPCs seriously requires paying attention to these possible tensions—both in general and with respect to international development research, in particular: On the one hand, there are attempts to contribute to societal change and ethical concerns of equity at the heart of international development research, and on the other hand, there is the relative risk of encountering asymmetries more likely.
In her recent article, Bender discusses several aspects of research–practice–collaborations (RPCs). In this commentary, we apply Bender's arguments to experiences in engineering research and development (R&D). We investigate the influence of interaction with practice partners on relevance, credibility, and legitimacy in the special engineering field of product development and analyze which methodological approaches are already being pursued for dealing with diverging interests and asymmetries and which steps will be necessary to include interests of civil society beyond traditional customer relations.
Research-Practice-Collaborations Addressing One Health and Urban Transformation. A Case Study
(2022)
One Health is an integrative approach at the interface of humans, animals and the environment, which can be implemented as Research-Practice-Collaboration (RPC) for its interdisciplinarity and intersectoral focus on the co-production of knowledge. To exemplify this, the present commentary shows the example of the Forschungskolleg “One Health and Urban Transformation” funded by the Ministry of Culture and Science of the State Government of Nord Rhine Westphalia in Germany. After analysis, the factors identified for a better implementation of RPC for One Health were the ones that allowed for constant communication and the reduction of power asymmetries between practitioners and academics in the co-production of knowledge. In this light, the training of a new generation of scientists at the boundaries of different disciplines that have mediation skills between academia and practice is an important contribution with great implications for societal change that can aid the further development of RPC.
Soil nutrient depletion threatens global food security and has been seriously underestimated for potassium (K) and several micronutrients. This is particularly the case for highly weathered soils in tropical countries, where classical soluble fertilizers are often not affordable or not accessible. One way to replenish macro- and micronutrients are ground silicate rock powders (SRPs). Rock forming silicate minerals contain most nutrients essential for higher plants, yet slow and inconsistent weathering rates have restricted their use in the past. Recent findings, however, challenge past agronomic objections which insufficiently addressed the factorial complexity of the weathering process. This review therefore first presents a framework with the most relevant factors for the weathering of SRPs through which several outcomes of prior studies can be explained. A subsequent analysis of 48 crop trials reveals the potential as alternative K source and multi-nutrient soil amendment for tropical soils, whereas the benefits for temperate soils are currently inconclusive. Beneficial results prevail for mafic and ultramafic rocks like basalts and rocks containing nepheline or glauconite. Several rock modifications are highly efficient in increasing the agronomic effectiveness of SRPs. Enhanced weathering of SRPs could additionally sequester substantial amounts of CO2 from the atmosphere and silicon (Si) supply can induce a broad spectrum of plant biotic and abiotic stress resistance. Recycling massive amounts of rock residues from domestic mining industries could furthermore resolve serious disposal challenges and improve fertilizer self-sufficiency. In conclusion, under the right circumstances, SRPs could not only advance low-cost and regional soil sustaining crop production but contribute to various sustainable development goals.
These times are very troubled ones. Not only do wars and political unrest seem to prevail in different regions of the world, but, corruption and fraud have reached an incredible dimension, too. It seems that societies have, to a large extent, lost values in which they had formerly believed in. These issues may be the background why at the moment Corporate Social Responsibility (CSR) as a voluntary commitment is discussed in public that intensively. However, one gets the impression that this rather often seems to be superficial. Therefore, it is time to do some in-depth research to identify whether there is real substance behind these discussions or not. Latin America is a big continent with a greater number of countries which are running through difficult times as to corruption and fraud. Consequently, the author studied the policy of the central employers association Consejo Empresarial de America Latina (CEAL) with respect to the role of CSR. On the basis of statements, news and results of studies being regularly published, conclusions were drawn to which extent social and environmental aspects, along the line of ISO 26000, are playing a relevant role.
In order to avoid a too narrow view of the issue, a holistic approach concerning the generalsituation of Latin America has been selected using parameters such as economic growth, increase of population, poverty, inequality, and the global responsibility for environment. Furthermore, apart from the central organization CEAL, regional and national institutions with a specific mission for spreading and implementing CSR and two communal projects were analyzed as well. The conclusion of the paper is that there are some CSR "lighthouses" but an urgent need exists to spread the idea of CSR more intensively across the continent. Corresponding recommendations about how to increase the relevance of CSR in Latin America are given at the end of the paper.
The decline of insect abundance and richness has been documented for decades and has received increased attention in recent years. In 2017, a study by Hallmann and colleagues on insect biomasses in German nature protected areas received a great deal of attention and provided the impetus for the creation of the project Diversity of Insects in Nature protected Areas (DINA). The aim of DINA was to investigate possible causes for the decline of insects in nature protected areas throughout Germany and to develop strategies for managing the problem.
A major issue for the protection of insects is the lack of insect-specific regulations for nature protected areas and the lack of a risk assessment and verification of the measures applied. Most nature protected areas border on or enclose agricultural land and are structured in a mosaic, resulting in an abundance of small and narrow areas. This leads to fragmentation or even loss of endangered habitats and thus threaten biodiversity. In addition, the impact of agricultural practices, especially pesticides and fertilisers, leads to the degradation of biodiversity at the boundaries of nature protected areas, reducing their effective size. All affected stakeholders need to be involved in solving these threats by working on joint solutions. Furthermore, agriculture in and around nature protected areas must act to promote biodiversity and utilise and develop methods that reverse the current trend. This also requires subsidies from the state to ensure economic sustainability and promote biodiversity-promoting practices.
In diesem Paper wird ein Modell eines Photovoltaik(PV)-Diesel-Hybrid-Systems aufgebaut. Dieses System besitzt neben einer PV-Anlage einen Batteriespeicher und ist an das öffentliche Stromnetz angeschlossen. Bei einem Ausfall aller drei Energiequellen stellt ein Dieselgenerator die Stromversorgung sicher. Mit Hilfe des erstellten Modells wird der Einfluss der unterschiedlichen Jahreszeiten und Wetterbedingungen auf den PV-Ertrag und das gesamte System im Zeitraum von Februar 2016 bis Februar 2017 untersucht. Die Messdaten dafür stammen von einem Krankenhaus in Akwatia, Ghana. Das Krankenhaus besitzt bereits eine PV-Anlage und einen Dieselgenerator als Backup.
Ein weiterer Aspekt der Untersuchung ist der Einfluss der Stromausfälle, die in dieser Region häufig vorkommen, auf den Einsatz des Generators.
Resultat der Untersuchung ist die Relevanz saisonaler und infrastruktureller Einflüsse auf die Betriebsweise des Systems. Mit Hilfe des erstellten Modells wurde analysiert, dass besonders während der Regenzeit im August die PV-Leistung sinkt und folglich viel Energie durch das öffentliche Stromnetz und den Generator bereitgestellt werden muss. Ein weiterer signifikanter Einbruch im PV-Ertrag ist zur Zeit des Harmattans im Januar zu verzeichnen.
Sustainable urban soil management is becoming increasingly crucial due to its vital role in climate and water regulation and its significant potential for storing soil organic carbon (SOC). This significance is emphasized considering the ongoing urbanization and climate change issues. Although SOC is influenced by many factors, such as soil type and climate fluctuations (temperature, precipitation patterns), on a regional scale, land use and management practices (e.g., fertilization, irrigation) can have a more significant impact on SOC storage and the balance of soil-atmosphere carbon fluxes. However, there is still a limited understanding of the amount of humus content in urban soils and the effects of urban development and management practices on soil health and carbon storage. We investigated how management practices in urban green spaces influence soil carbon storage as the primary indicator of soil health.
The present study was carried out in the Bonn-Rhein-Sieg area, as the region is vital in terms of sustainable urban and regional development with a high population density (Rhein-Sieg district: 338.4, Bonn: 520.9 inhabitants/km2) in Germany. A survey was conducted with owners and managers of urban private (e.g., allotment and backyard garden) and public green spaces on the practices for the most common vegetation types (e.g., lawn, vegetable, ornamental). In the autumn and winter of 2022, 248 soil samples (0–20 cm depth) were collected from 95 private and public green spaces in the study area and analyzed for physiochemical and biological properties. Multivariate Analysis of Variance (MANOVA) was performed to assess the effects of different management practices on soil properties.
Our results indicate that the average SOC stock in public green areas (94.67 Mg ha-1) is substantially higher than in private ones (house garden 67.72 Mg ha-1, allotment garden 73.15 Mg ha-1). Moreover, urban green spaces with vegetables (91.66 Mg ha-1) and ornamentals (85.05 mg ha-1) show greater SOC stock levels when comparing vegetation types (lawn 62.48 Mg ha-1). Significant differences in SOC are also found for various management practices. Specifically, the monthly fertilization schedule resulted in higher SOC levels (127.37 Mg ha⁻¹) compared to the yearly fertilization schedule (76.88 Mg ha⁻¹). Additionally, the use of organic fertilizers contributed to increased SOC levels (84.40 Mg ha⁻¹) in contrast to mineral fertilizer applications (65.31 Mg ha⁻¹). The average SOC stock in all the studied urban green spaces (85 mg ha-1) was higher than the average SOC stock in arable soils in Germany (47.30 Mg ha-1). The higher SOC in the region could be due to vegetation types and fertilization frequencies, which show statistically significant effects (p-value <0.001). Other management practices (e.g., irrigation type and frequency) did not show a significant effect. Our findings highlight the significance of soil management practices, particularly in selecting vegetation types and determining fertilization frequency, as essential factors influencing urban SOC.
Argentina substantially contributes to the global organic agriculture and food sector due to its large areas of organically managed agricultural land. However, most of the organic production is intended for export. Overall, food supply for the domestic organic market is hardly tapped. Based on this, we investigate the current importance of organic agriculture and food production as well as consumption attitudes and behavior within the country. The novelty of the study also lies in the observation, documentation and analysis of latest stakeholder‐driven developments towards organic agriculture and food. Furthermore, the publication allows the Argentinean organic market to be significantly more visible for the international audience.
This work proposes a novel approach for probabilistic end-to-end all-sky imager-based nowcasting with horizons of up to 30 min using an ImageNet pre-trained deep neural network. The method involves a two-stage approach. First, a backbone model is trained to estimate the irradiance from all-sky imager (ASI) images. The model is then extended and retrained on image and parameter sequences for forecasting. An open access data set is used for training and evaluation. We investigated the impact of simultaneously considering global horizontal (GHI), direct normal (DNI), and diffuse horizontal irradiance (DHI) on training time and forecast performance as well as the effect of adding parameters describing the irradiance variability proposed in the literature. The backbone model estimates current GHI with an RMSE and MAE of 58.06 and 29.33 W m−2, respectively. When extended for forecasting, the model achieves an overall positive skill score reaching 18.6 % compared to a smart persistence forecast. Minor modifications to the deterministic backbone and forecasting models enables the architecture to output an asymmetrical probability distribution and reduces training time while leading to similar errors for the backbone models. Investigating the impact of variability parameters shows that they reduce training time but have no significant impact on the GHI forecasting performance for both deterministic and probabilistic forecasting while simultaneously forecasting GHI, DNI, and DHI reduces the forecast performance.
Renewable energies play an increasingly important role for energy production in Europe. Unlike coal or gas powerplants, solar energy production is highly variable in space and time. This is due to the strong variability of cloudsand their influence on the surface solar irradiance. Especially in regions with large contribution from photovoltaicpower production, the intermittent energy feed-in to the power grid can be a risk for grid stability. Therefore goodforecasts of temporal and spatial variability of surface irradiance are necessary to be able to properly regulate thepower supply.
In view of the rapid growth of solar power installations worldwide, accurate forecasts of photovoltaic (PV) power generation are becoming increasingly indispensable for the overall stability of the electricity grid. In the context of household energy storage systems, PV power forecasts contribute towards intelligent energy management and control of PV-battery systems, in particular so that self-sufficiency and battery lifetime are maximised. Typical battery control algorithms require day-ahead forecasts of PV power generation, and in most cases a combination of statistical methods and numerical weather prediction (NWP) models are employed. The latter are however often inaccurate, both due to deficiencies in model physics as well as an insufficient description of irradiance variability.
Incoming solar radiation is an important driver of our climate and weather. Several studies (see for instance Frank et al. 2018) have revealed discrepancies between ground-based irradiance measurements and the predictions of regional weather models. In the realm of electricity generation, accurate forecasts of solar photovoltaic (PV)energy yield are becoming indispensable for cost-effective grid operation: in Germany there are 1.6 million PVsystems installed, with a nominal power of 46 GW (Bundesverband Solarwirtschaft 2019). The proliferation of PV systems provides a unique opportunity to characterise global irradiance with unprecedented spatiotemporalresolution, which in turn will allow for highly resolved PV power forecasts.
This paper addresses long-term historical changes in solar irradiance in West Africa (3 to 20° N and 20° W to 16° E) and the implications for photovoltaic systems. Here, we use satellite irradiance (Surface Solar Radiation Data Set – Heliosat, Edition 2.1 – SARAH-2.1) and temperature data from a reanalysis (ERA5) to derive photovoltaic yields. Based on 35 years of data (1983–2017), the temporal and regional variability as well as long-term trends in global and direct horizontal irradiance are analyzed. Furthermore, a detailed time series analysis is undertaken at four locations. According to the high spatial resolution SARAH-2.1 data record (0.05°×0.05°), solar irradiance is largest (up to a 300 W m−2 daily average) in the Sahara and the Sahel zone with a positive trend (up to 5 W m−2 per decade) and a lower temporal variability (<75 W m−2 between 1983 and 2017 for daily averages). In contrast, the solar irradiance is lower in southern West Africa (between 200 W m−2 and 250 W m−2) with a negative trend (up to −5 W m−2 per decade) and a higher temporal variability (up to 150 W m−2). The positive trend in the north is mostly connected to the dry season, whereas the negative trend in the south occurs during the wet season. Both trends show 95 % significance. Photovoltaic (PV) yields show a strong meridional gradient with the lowest values of around 4 kWh kWp−1 in southern West Africa and values of more than 5.5 kWh kWp−1 in the Sahara and Sahel zone.
The Life Cycle Assessment (LCA) approach is the most important tool in the evaluation of environmental (sustainability) impacts of products and processes. We used the method to conduct an impact analysis with regard to raw material inputs (pulp) for the German paper production industry. In our analysis, we compare the environmental effects of primary sulphate pulp, scrap paper pulp and grass-based pulp and estimate their impacts in the impact categories "greenhouse gas emissions", "eutrophication" as well as "energy and water consumption". Furthermore, we discuss the opportunities of the methodical approach and some general problems and limits of the application of a LCA. In conclusion, we found environmental advantages for the use of grass as an alternative resource in the German paper production industry, especially in the fields of transport and water consumption.
The ongoing coronavirus disease 2019 (COVID-19) pandemic threatens global health thereby causing unprecedented social, economic, and political disruptions. One way to prevent such a pandemic is through interventions at the human-animal-environment interface by using an integrated One Health (OH) approach. This systematic literature review documented the three coronavirus outbreaks, i.e. SARS, MERS, COVID-19, to evaluate the evolution of the OH approach, including the identification of key OH actions taken for prevention, response, and control.
The OH understandings identified were categorized into three distinct patterns: institutional coordination and collaboration, OH in action/implementation, and extended OH (i.e. a clear involvement of the environmental domain). Across all studies, OH was most often framed as OH in action/implementation and least often in its extended meaning. Utilizing OH as institutional coordination and collaboration and the extended OH both increased over time. OH actions were classified into twelve sub-groups and further categorized as classical OH actions (i.e. at the human-animal interface), classical OH actions with outcomes to the environment, and extended OH actions.
The majority of studies focused on human-animal interaction, giving less attention to the natural and built environment. Different understandings of the OH approach in practice and several practical limitations might hinder current efforts to achieve the operationalization of OH by combining institutional coordination and collaboration with specific OH actions. The actions identified here are a valuable starting point for evaluating the stage of OH development in different settings. This study showed that by moving beyond the classical OH approach and its actions towards a more extended understanding, OH can unfold its entire capacity thereby improving preparedness and mitigating the impacts of the next outbreak.
Cultivation of Miscanthus x giganteus L. (Mis) with annual harvest of biomass could provide an additional C source for farmers. To test the potential of Mis-C for immobilizing inorganic N from slurry or manure and as a C source for soil organic matter build-up in comparison to wheat (Triticum aestivum L.) straw (WS), a greenhouse experiment was performed. Pot experiments with ryegrass (Lolium perenne L.) were set up to investigate the N dynamics of two organic fertilisers based on Mis at Campus Klein-Altendorf, Germany. The two fertilisers, a mixture of cattle slurry and Mis as well as cattle manure from Mis-bedding material resulted in a slightly higher N immobilisation. Especially at the 1st and 2nd harvest, they were partly significantly different compared with the WS treatments. The fertilisers based on Mis resulted in a slightly higher microbial biomass C and microbial biomass N and thus can be identified as an additional C source to prevent nitrogen losses and for the build-up of soil organic matter (SOM) in the long-term.
Die vorliegende Forschungsarbeit behandelt die Filtrierung von sozialen Medien durch die Content Moderatoren. Die Content Moderatoren sind Menschen, die unter schlechten Arbeitsbedingungen und hoher psychischer Belastung Plattformen wie Facebook tagtäglich von strafbaren Inhalten filtern. Durch dieses Löschregime werden zwar gewaltzeigende Inhalte gelöscht, aber auch aufklärende oder künstlerische Inhalte zensiert.
Mithilfe von durchgeführten Fokusgruppendiskussionen wurde der Einfluss der Gruppenzusammensetzung und Darbietung positiver und negativer Informationen auf die individuelle und eindimensionale Wahrnehmung der Teilnehmer bezüglich sozialer Medien, Content Moderatoren und Löschrichtlinien erforscht.
Die Ergebnisse zeigen, dass die Darbietung der Informationen keinen Einfluss auf die mehrdimensionale Wahrnehmung der Probanden hatte und sie unabhängig von der Gruppenzusammensetzung nonkonforme Meinungen vertraten. Trotz des erweiterten Wissenstandes und der entwickelten Alternativlösungen äußerten die meisten Probanden nicht die Absicht, ihr Nutzungsverhalten künftig zu ändern. Trotz der Annahme, dass die meisten Probanden eine eindimensionale Wahrnehmung sozialer Medien haben, zeigten die Ergebnisse, dass viele Probanden eine ähnlich positive und kritische Haltung gegenüber den Plattformen hatten. Darüber hinaus wird deutlich, dass es einen starken Forschungsbedarf in Bezug auf die Langzeitfolgen der Arbeit als Content Moderator und Auswirkungen von Zensur und Filtrierung auf die Nutzer sozialer Medien gibt.
Das Thema Nachhaltigkeit hat sich in der heutigen Zeit in vielerlei Hinsicht weiterentwickelt. Auch bei der Entwicklung von Produkten ist der Aspekt der Nachhaltigkeit angekommen und wird vermehrt umgesetzt. Dies hat zur Folge, dass auch der Konsument sich mit der Nachhaltigkeit seines Produkts auseinandersetzt.
Die vorliegende Arbeit behandelt die Fragestellung, ob der Aspekt der Nachhaltigkeit auch bei der Kaufentscheidung eine Rolle spielt. Fokussiert wurden besonders die Aspekte: Nachhaltigkeit und Marketing, Wahrnehmung von nachhaltigen Aspekten der Unternehmen, sowie der Produkte, Vertrauen der Konsumenten in Siegel und die soziale Erwartungshaltung der Konsumenten.
Die Analyse resultiert auf der Basis eines durchgeführten Experiments sowie einer schriftlichen Befragung der 73 Probanden, bestehend aus Studenten der Hochschule Bonn-Rhein-Sieg.
Die Ergebnisse dieser Studie zeigen nicht nur den Handlungsbedarf der Unternehmen, sondern auch die Wahrnehmung der Konsumenten zu Produkten und Unternehmen und dass der Aspekt der Nachhaltigkeit auch bei täglichen Kaufentscheidungen eine Rolle spielen kann.
In Zeiten deutlicher Auswirkungen des Klimawandels und gravierender sozialer Missstände in Teilen der Welt drängen sich dringender denn je für die Weltgemeinschaft die Fragen nach Handlungsoptionen zum Erreichen nachhaltiger Entwicklung auf. Dementsprechend ist auch der öffentliche Sektor gefragt seinen Beitrag zu leisten. Als ein wirkungsvoller Beitrag ist die Etablierung nachhaltiger öffentlicher Beschaffung zu nennen. Um diesen Beitrag adäquat umzusetzen, müssen unter anderem die Richtlinien und Gesetze, die die öffentliche Beschaffung regeln, ausreichend Umsetzungsmöglichkeiten dafür bieten. Mit der jüngsten europäischen Vergaberechtsreform und der daraufhin verabschiedeten deutschen Anpassung der Gesetze ist der Grundstein dafür gelegt worden. Welche erfolgsversprechenden Umsetzungsmöglichkeiten diese rechtliche Basis nun den Kommunen in Deutschland als Hauptakteuren öffentlicher Beschaffung bietet und welche weiteren Erfolgsfaktoren für die Umsetzung nachhaltiger öffentlicher Beschaffung auf kommunaler Ebene entscheidend sind, ist Thema dieses Arbeitspapiers. Ein Praxischeck der Erfolgsfaktoren wird am Beispiel der Stadt Bonn, stellvertretend für die kommunale Ebene in NRW vorgenommen.
Intention: Within the research project EnerSHelF (Energy-Self-Sufficiency for Health Facilities in Ghana), i. a. energy-meteorological and load-related measurement data are collected, for which an overview of the availability is to be presented on a poster.
Context: In Ghana, the total electricity consumed has almost doubled between 2008 and 2018 according to the Energy Commission of Ghana. This goes along with an unstable power grid, resulting in power outages whenever electricity consumption peaks. The blackouts called "dumsor" in Ghana, pose a severe burden to the healthcare sector. Innovative solutions are needed to reduce greenhouse gas emissions and improve energy and health access.
Long-term variability of solar irradiance and its implications for photovoltaic power in West Africa
(2020)
West Africa is one of the least developed regions in the world regarding the energy availability and energy security. Located close to the equator West Africa receives high amounts of global horizontal irradiance (GHI). Thus, solar power and especially photovoltaic (PV) systems seem to be a promising solution to provide electricity with low environmental impact. To plan and to dimension a PV power system climatological data for global horizontal irradiance (GHI) and its variability need to be taken into account. However, ground based measurements of irradiances are not available continuously and cover only a few discrete locations.
Solar photovoltaic power output is modulated by atmospheric aerosols and clouds and thus contains valuable information on the optical properties of the atmosphere. As a ground-based data source with high spatiotemporal resolution it has great potential to complement other ground-based solar irradiance measurements as well as those of weather models and satellites, thus leading to an improved characterisation of global horizontal irradiance. In this work several algorithms are presented that can retrieve global tilted and horizontal irradiance and atmospheric optical properties from solar photovoltaic data and/or pyranometer measurements. The method is tested on data from two measurement campaigns that took place in the Allgäu region in Germany in autumn 2018 and summer 2019, and the results are compared with local pyranometer measurements as well as satellite and weather model data. Using power data measured at 1 Hz and averaged to 1 min resolution along with a non-linear photovoltaic module temperature model, global horizontal irradiance is extracted with a mean bias error compared to concurrent pyranometer measurements of 5.79 W m−2 (7.35 W m−2) under clear (cloudy) skies, averaged over the two campaigns, whereas for the retrieval using coarser 15 min power data with a linear temperature model the mean bias error is 5.88 and 41.87 W m−2 under clear and cloudy skies, respectively.
During completely overcast periods the cloud optical depth is extracted from photovoltaic power using a lookup table method based on a 1D radiative transfer simulation, and the results are compared to both satellite retrievals and data from the Consortium for Small-scale Modelling (COSMO) weather model. Potential applications of this approach for extracting cloud optical properties are discussed, as well as certain limitations, such as the representation of 3D radiative effects that occur under broken-cloud conditions. In principle this method could provide an unprecedented amount of ground-based data on both irradiance and optical properties of the atmosphere, as long as the required photovoltaic power data are available and properly pre-screened to remove unwanted artefacts in the signal. Possible solutions to this problem are discussed in the context of future work.
Solar photovoltaic power output is modulated by atmospheric aerosols and clouds and thus contains valuable information on the optical properties of the atmosphere. As a ground-based data source with high spatiotemporal resolution it has great potential to complement other ground-based solar irradiance measurements as well as those of weather models and satellites, thus leading to an improved characterisation of global horizontal irradiance. In this work several algorithms are presented that can retrieve global tilted and horizontal irradiance and atmospheric optical properties from solar photovoltaic data and/or pyranometer measurements. Specifically, the aerosol (cloud) optical depth is inferred during clear sky (completely overcast) conditions. The method is tested on data from two measurement campaigns that took place in Allgäu, Germany in autumn 2018 and summer 2019, and the results are compared with local pyranometer measurements as well as satellite and weather model data. Using power data measured at 1 Hz and averaged to 1 minute resolution, the hourly global horizontal irradiance is extracted with a mean bias error compared to concurrent pyranometer measurements of 11.45 W m−2, averaged over the two campaigns, whereas for the retrieval using coarser 15 minute power data the mean bias error is 16.39 W m−2.
During completely overcast periods the cloud optical depth is extracted from photovoltaic power using a lookup table method based on a one-dimensional radiative transfer simulation, and the results are compared to both satellite retrievals as well as data from the COSMO weather model. Potential applications of this approach for extracting cloud optical properties are discussed, as well as certain limitations, such as the representation of 3D radiative effects that occur under broken cloud conditions. In principle this method could provide an unprecedented amount of ground-based data on both irradiance and optical properties of the atmosphere, as long as the required photovoltaic power data are available and are properly pre-screened to remove unwanted artefacts in the signal. Possible solutions to this problem are discussed in the context of future work.
The electricity grid of the future will be built on renewable energy sources, which are highly variable and dependent on atmospheric conditions. In power grids with an increasingly high penetration of solar photovoltaics (PV), an accurate knowledge of the incoming solar irradiance is indispensable for grid operation and planning, and reliable irradiance forecasts are thus invaluable for energy system operators. In order to better characterise shortwave solar radiation in time and space, data from PV systems themselves can be used, since the measured power provides information about both irradiance and the optical properties of the atmosphere, in particular the cloud optical depth (COD). Indeed, in the European context with highly variable cloud cover, the cloud fraction and COD are important parameters in determining the irradiance, whereas aerosol effects are only of secondary importance.
The rapid increase in solar photovoltaic (PV) installations worldwide has resulted in the electricity grid becoming increasingly dependent on atmospheric conditions, thus requiring more accurate forecasts of incoming solar irradiance. In this context, measured data from PV systems are a valuable source of information about the optical properties of the atmosphere, in particular the cloud optical depth (COD). This work reports first results from an inversion algorithm developed to infer global, direct and diffuse irradiance as well as atmospheric optical properties from PV power measurements, with the goal of assimilating this information into numerical weather prediction (NWP) models.
Photovoltaic (PV) power data are a valuable but as yet under-utilised resource that could be used to characterise global irradiance with unprecedented spatio-temporal resolution. The resulting knowledge of atmospheric conditions can then be fed back into weather models and will ultimately serve to improve forecasts of PV power itself. This provides a data-driven alternative to statistical methods that use post-processing to overcome inconsistencies between ground-based irradiance measurements and the corresponding predictions of regional weather models (see for instance Frank et al., 2018). This work reports first results from an algorithm developed to infer global horizontal irradiance as well as atmospheric optical properties such as aerosol or cloud optical depth from PV power measurements.
Solar energy is one option to serve the rising global energy demand with low environmental impact.1 Building an energy system with a considerable share of solar power requires long-term investment and a careful investigation of potential sites. Therefore, understanding the impacts from varying regionally and locally determined meteorological conditions on solar energy production will influence energy yield projections. Clouds are moving on a short term timescale and have a high influence on the available solar radiation, as they absorb, reflect and scatter parts of the incoming light.2 However, the impact of cloudiness on photovoltaic power yields (PV) and cloud induced deviations from average yields might vary depending on the technology, location and time scale under consideration.
Intersectoral collaborations are an integral component of the prevention and control of diseases in a complex health system. On the one hand, One Health (OH) is promoting the establishment of intersectoral collaborations for prevention at the human-animal-environment interface. On the other hand, operationalising OH can only be realized through intersectoral collaborations.
This work contributes to broadening the knowledge of the process for operationalising OH by analysing the governance structures behind different initiatives that tackle health problems at the human-animal-environment interface. The cases taken as examples for the analysis are the control and response to rabies and avian influenza under “classical OH”, and the management of floods and droughts for insights into “extended OH”. Data from Ghana and India were collected and compared to identify the key elements that enable ISC for OH.
Despite the case studies being heterogeneous in terms of their geographic, economic, social, cultural, and historical contexts, strong similarities were identified on how intersectoral collaborations in OH were initiated, managed, and taken to scale.
The actions documented for rabies prevention and control were historically based on one sector being the leader and implementer of activities, while avian influenza management relied more on intersectoral collaborations with clearly defined sectoral responsibilities. The management of the impact of flood and droughts on health provided a good example of intersectoral collaborations achieved by sectoral integration; however, the human health component was only involved in the response stage in the case of Ghana, while for India, there were broader schemes of intersectoral collaborations for prevention, adaptation, and response concerning climate change and disaster.
Hydrogen as a versatile, greenhouse gas-free energy carrier will play an important role in our future economy. Yet sustainable, competitive production and distribution of hydrogen remains a challenge. Highly integrated solar water splitting systems aim to combine solar energy harvesting and electrolysis in a single device, similar to a photovoltaic module.[1] Such a system can produce hydrogen locally without the requirement to be connected to the electricity grid. Unlike large electrolysis that draws power from the grid, the power density of such a device is reduced so far that it does not require active cooling, but its operating temperature will closely follow outdoor conditions.
Here, we present our work on high-efficiency integrated solar water splitting devices based on multi-junction solar absorbers. The light-absorbing component is sensitive to the shape of the solar spectrum and generally becomes more efficient at lower temperatures. Catalysis, on the other hand, benefits from higher temperatures. These conflicting trends wih respect to the temperature impact the design of the solar hydrogen production system. We analyse how the local climate affects production efficiency[2] and show in a lab study that adequate system design allows efficient operation at temperatures as low as -20°C.[3] These insights can help to design small-scale distributed solar hydrogen production for both temperate regions, but also more extreme climatic conditions.
Contract-based nature protection schemes are a voluntary mechanism, with a limited contract duration, that aim to raise the acceptance of biodiversity conservation practices in agriculture among farmers and other land users. The purpose of this paper is to analyse the institutional settings of contract-based nature protection based on the– “Institutions of Sustainability” (IoS) framework in the German Rhine-Sieg district, and to outline the way in which policy measures should be designed to encourage farmers to participate in contract-based nature protection programmes. This was achieved by answering research questions to identify the challenges, potentials and obstacles of a contract-based nature protection scheme in different “sub-arenas” as defined in the IoS framework. Qualitative research methods were used as the methodology. The analysis shows that main constraints for sufficient implementation of contract-based nature protection schemes are the limited consideration of the impact of climate change during the contract period, the limited consideration of regional conditions as regards the measures taken on the ground and an inflexible contract duration.
The paper examines the effectiveness of transgovernmental policy networks as a governance structure for policy diffusion. The analysis is based on a survey including 50 social protection policy maker and technical practitioner who are country delegates to transgovernmental policy networks within the policy area of social protection. The paper provides anecdotal empirical evidence that policy networks contribute to policy diffusion by inducing mutual learning processes.
In intensively used agricultural landscapes, path margins are one of the few refuges and nurseries for wildlife. They provide e. g. food sources and overwintering opportunities for many insects, serve as migration corridors for animals, protect soil from erosion, increase its water-holding capacity, and increase soil organic carbon, contributing thus directly to biodiversity conservation and climate change mitigation. Path margins are often municipally owned but used and managed by agriculture. For a path margin to be functional, certain conditions must be fulfilled, such as the width, the botanical composition, and how it is managed through the seasons. Therefore, it must be managed under specific requirements. A multifunctional path margin can be achieved only through the commitment of all stakeholders (e.g., farmers, municipalities, conservationists, and civil society).
West Africa has great potential for the use of solar energy systems, as it has both a high solar radiation rate and a lack of energy production. West Africa is a very aerosol-rich region, whose effects on photovoltaic (PV) use are due to both atmospheric conditions and existing solar technology. This study reports the variability of aerosol optical properties in the city of Koforidua, Ghana over the period 2016 to 2020, and their impact on the radiation intensity and efficiency of a PV cell. The study used AERONET ground (Giles et al., 2019) and satellite data produced by CAMS (Gschwind, et al., 2019), which both provide aerosol optical depth (AOD) and metrological parameters used for radiative transfer calculations with libRadtran (Emde, et al., 2016). A spectrally resolved PV model (Herman-Czezuch et al., 2022) is then used to calculate the PV yield of two PV technologies: polycrystalline and amorphous silicon. It is observed that for both data sets, the aerosol is mainly composed of dust and organic matter, with a very increased AOD load during the harmattan period (December-February), also due to the fires observed during this period.
Improving insect conservation management through insect monitoring and stakeholder involvement
(2023)
In recent years, the decline of insect biodiversity and the imminent loss of provided ecosystem functions and services has received public attention and raised the demand for political action. The complex, multi-causal contributors to insect decline require a broad interdisciplinary and cross-sectoral approach that addresses ecological and social aspects to find sustainable solutions. The project Diversity of Insects in Nature protected Areas (DINA) assesses insect communities in 21 nature reserves in Germany, and considers interactions with plant diversity, pesticide exposure, spatial and climatic factors. The nature reserves border on agricultural land, to investigate impacts on insect diversity. Part of the project is to obtain scientific data from Malaise traps and their surroundings, while another part involves relevant stakeholders to identify opportunities and obstacles to insect diversity conservation. Our results indicate a positive association between insect richness and biomass. Insect richness was negatively related to the number of stationary pesticides (soil and vegetation), pesticides measured in ethanol, the amount of area in agricultural production, and precipitation. Our qualitative survey along with stakeholder interviews show that there is general support for insect conservation, while at the same time the stakeholders expressed the need for more information and data on insect biodiversity, as well as flexible policy options. We conclude that conservation management for insects in protected areas should consider a wider landscape. Local targets of conservation management will have to integrate different stakeholder perspectives. Scientifically informed stakeholder dialogues can mediate conflicts of interests, knowledge, and values to develop mutual conservation scenarios.
Argentina substantially contributes to the global organic agriculture and food sector due to its large areas of organically managed agricultural land. However, most of the organic production is foreseen for export. Overall, food supply for the domestic organic market is hardly tapped. This study investigates the current importance of organic agriculture and food production as well as its consumption within the country. The novelty of the study also lies in the observation, documentation and analysis of latest stakeholder-driven developments towards organic agriculture and food. The publication allows to make the Argentinian organic market significantly more visible for the international audience.
In contrast to the German power supply, the energy supply in many West African countries is very unstable. Frequent power outages are not uncommon. Especially for critical infrastructures, such as hospitals, a stable power supply is vital. To compensate for the power outages, diesel generators are often used. In the future, these systems will increasingly be supplemented by PV systems and storage, so that the generator will have to be used less or not at all when needed. For the design and operation of such systems, it is necessary to better understand the atmospheric variability of PV power generation. For example, there are large variations between rainy and dry seasons, between days with high and low dust levels - caused by sandstorms (harmattan) or urban air pollution.
Due to the policy goals for sustainable energy production, renewable energy plants such as photovoltaics are increasingly in use. The energy production from solar radiation depends strongly on atmospheric conditions. As the weather mostly changes, electrical power generation fluctuates, making technical planning and control of power grids to a complex problem.
Atmospheric aerosols affect the power production of solar energy systems. Their impact depends on both the atmospheric conditions and the solar technology employed. By being a region with a lack in power production and prone to high solar insolation, West Africa shows high potential for the application of solar power systems. However, dust outbreaks, containing high aerosol loads, occur especially in the Sahel, located between the Saharan desert in the north and the Sudanian Savanna in the south. They might affect the whole region for several days with significant effects on power generation. This study investigates the impact of atmospheric aerosols on solar energy production for the example year 2006 making use of six well instrumented sites in West Africa. Two different solar power technologies, a photovoltaic (PV) and a parabolic through (PT) power plant, are considered. The daily reduction of solar power due to aerosols is determined over mostly clear-sky days in 2006 with a model chain combining radiative transfer and technology specific power generation. For mostly clear days the local daily reduction of PV power (at alternating current) (PVAC) and PT power (PTP) due to the presence of aerosols lies between 13 % and 22 % and between 22 % and 37 %, respectively. In March 2006 a major dust outbreak occurred, which serves as an example to investigate the impact of an aerosol extreme event on solar power. During the dust outbreak, daily reduction of PVAC and PTP of up to 79 % and 100 % occur with a mean reduction of 20 % to 40 % for PVAC and of 32 % to 71 % for PTP during the 12 days of the event.
Solar energy plants are one of the key options to serve the rising global energy need with low environmental impact. Aerosols reduce global solar radiation due to absorption and scattering and therewith solar energy yields. Depending on the aerosol composition and size distribution they reduce the direct component of the solar radiation and modify the direction of the diffuse component compared to standard atmospheric conditions without aerosols.
Impact of atmospheric aerosols on photovoltaic energy production - Scenario for the Sahel zone
(2017)
Photovoltaic (PV) energy is one option to serve the rising global energy need with low environmental impact. PV is of particular interest for local energy solutions in developing countries prone to high solar insolation. In order to assess the PV potential of prospective sites, combining knowledge of the atmospheric state modulating solar radiation and the PV performance is necessary. The present study discusses the PV power as function of atmospheric aerosols in the Sahel zone for clear-sky-days. Daily yields for a polycrystalline silicon PV module are reduced by up to 48 % depending on the climatologically-relevant aerosol abundances.
Solar energy is one option to serve the rising global energy demand with low environmental impact. Building an energy system with a considerable share of solar power requires long-term investment and a careful investigation of potential sites. Therefore, understanding the impacts from varying regionally and locally determined meteorological conditions on solar energy production will influence energy yield projections.
West Africa has a great potential for the application of solar energy systems, as it combines high levels of solar irradiance with a lack of energy production. Southern West Africa is a region with a very high aerosol load. Urbanization, uncontrolled fires, traffic as well as power plants and oil rigs lead to increasing anthropogenic emissions. The naturally circulating north winds bring mineral dust from the Sahel and Sahara and monsoons - sea salt and other oceanic compounds from the south. The EU-funded Dynamics-Aerosol-Chemistry-Cloud Interactions in West Africa (DACCIWA) project (2014–2018), dlivered the most complete dataset of the atmosphere over the region to date. In our study, we use in-situ measured optical properties of aerosols from the airborne campaign over the Gulf of Guinea and inland, and from ground measurements in coastal cities.
Urban food systems consist of many stakeholders with different perspectives, different interests and different governance tools. This study aimed at developing potential future scenarios for the food system of Cologne by analysing the system with a Delphi approach. In our research-design, the suitability of the Delphi-method was evaluated not only as a tool for future modelling and scenario design, but also as a communication tool among the group of participants on a multi-stakeholder-platform. As a case study, the Food Policy Council of Cologne, Germany was used. Cologne can be seen as a forerunner among German cities in the development of a new urban food policy. Some of the successful steps to re-envisioning food as an urban system include joining the Milan Urban Food Policy Pact, the decision of the City Council to become an edible city and the establishment of a Food Policy Council. For the study it was important to capture participants’ visions of a common goal regarding the governance of the urban food system and also to identify mental ‘silos’. It was obvious that the municipality of Cologne together with the Food Policy Council made great efforts towards participatory processes to build a vision for a sustainable and regional food supply. However, many stakeholder-groups in the process still work exclusively among themselves and do not actively practice the confrontation with the viewpoints of other relevant groups. This supports the maintenance of ‘silos’ and leaves little room for face-to-face discussions. Therefore, the primary aim of this study is to explore key components of food provisioning in the future for Cologne while confronting all stakeholders (municipal administration and politicians, farmers and food activists) with the perspectives of all group members. We used a multi-stakeholder Delphi approach with 19 panellists to find out essential components of the municipal regional food provisioning system in Cologne. Unique in this Delphi study is the bringing together of municipal administration, regional urban farmers and food activists. The research is still on-going, but preliminary results show that more communication among all relevant actors, especially horizontally among different city departments, in the urban food system is needed.
In January 2015, German retail and industry jointly started a sector-wide initiative ("Initiative Tierwohl" - ITW) to improve animal welfare standards. The principle of the ITW is communicated mostly via the websites of ITW and its participating companies. However, uncertainty remained whether or not these websites provide the necessary information consumers need on the ITW products. Based on Schwartz's basic human values, different types of consumers were identified by a cluster analysis (ward-method, k-means). The results showed that depending on expressed meta‐values (Self-Transcendence/Openness to Change Self-Enhancement or Conservation), respondents had different specific information sources and needs. Online sources were rarely mentioned, the majority of consumers referred to brochures, flyers and interpersonal contacts.
Estimates of global horizontal irradiance (GHI) from reanalysis and satellite-based data are the most important information for the design and monitoring of PV systems in Africa, but their quality is unknown due to the lack of in situ measurements. In this study, we evaluate the performance of hourly GHI from state-of-the-art reanalysis and satellite-based products (ERA5, CAMS, MERRA-2, and SARAH-2) with 37 quality-controlled in situ measurements from novel meteorological networks established in Burkina Faso and Ghana under different weather conditions for the year 2020. The effects of clouds and aerosols are also considered in the analysis by using common performance measures for the main quality attributes and a new overall performance value for the joint assessment. The results show that satellite data performs better than reanalysis data under different atmospheric conditions. Nevertheless, both data sources exhibit significant bias of more than 150 W/m2 in terms of RMSE under cloudy skies compared to clear skies. The new measure of overall performance clearly shows that the hourly GHI derived from CAMS and SARAH-2 could serve as viable alternative data for assessing solar energy in the different climatic zones of West Africa.
Reliable and regional differentiated power forecasts are required to guarantee an efficient and economic energy transition towards renewable energies. Amongst other renewable energy technologies, e.g. wind mills, photovoltaic systems are an essential component of this transition being cost-efficient and simply to install. Reliable power forecasts are however required for a grid integration of photovoltaic systems, which among other data requires high-resolution spatio-temporal global irradiance data. Hence the generation of robust reviewed global irradiance data is an essential contribution for the energy transition.
Reliable and regional differentiated power forecasts are required to guarantee an efficient and economic energy transition towards renewable energies. Amongst other renewable energy technologies, e.g. wind mills, photovoltaic (PV) systems are an essential component of this transition being cost-efficient and simply to install. Reliable power forecasts are however required for a grid integration of photovoltaic systems, which among other data requires high-resolution spatio-temporal global irradiance data.
Pursuant to Sustainable Development Goal (SDG) 15 of the 2030 Agenda for Sustainable Development of the United Nations, one pivotal target is to halt biodiversity loss. This paper’s objective is to analyze why and how German farmers hesitate to implement more than the prescriptive measures with regard to cross compliance and direct payments under the European Common Agricultural Policy (CAP) and what their aspirations are for possible incentives to bring biodiversity into focus. By applying a mixed methods approach, we investigate the experience of individual farmers by means of a qualitative approach followed by a quantitative study. This analysis sheds light on how farmers perceive indirect influencing factors and how these factors play a non-negligible role in farmers´ commitment to biodiversity. Economy, policy and society are intertwined and need to be considered from a multi-faceted perspective. In addition, an in-depth analysis is conducted based on online focus group discussions to determine whether farmers accept financial support, focusing on both action- and success-oriented payments. Our results highlight the importance of paying attention to the heterogeneity of farmers, their locations and, consequently, farmers’ different views on indirect drivers influencing agricultural processes, showing the complexity of the problem. Although farmers’ expectations can be met with financial allocations, other aspects must also be taken into account.
Green infrastructure improves environmental health in cities, benefits human health, and provides habitat for wildlife. Increasing urbanization has demanded the expansion of urban areas and transformation of existing cities. The adoption of compact design in urban planning is a recommended strategy to minimize environmental impacts; however, it may undermine green infrastructure networks within cities as it sets a battleground for urban space. Under this scenario, multifunctionality of green spaces is highly desirable but reconciling human needs and biodiversity conservation in a limited space is still a challenge. Through a systematic review, we first compiled urban green space's characteristics that affect mental health and urban wildlife support, and then identified potential synergies and trade-offs between these dimensions. A framework based on the One Health approach is proposed, synthesizing the interlinkages between green space quality, mental health, and wildlife support; providing a new holistic perspective on the topic. Looking at the human-wildlife-environment relationships simultaneously may contribute to practical guidance on more effective green space design and management that benefit all dimensions.
Food losses occur for many reasons at all stages of supply chains for fruits, vegetables and potatoes. They cause immense economic, environmental and social costs – not only in developing countries but also in developed countries. According to the European Commission, about 90 million tonnes of food are wasted annually in Europe alone. However, particularly for the early stages of supply chains for fruits, vegetables and potatoes there is still a lack of reliable data. Thus, one objective of this study is to contribute to the quantification of food losses between field and retail, where the main focus is set on potatoes, apples, carrots, strawberries and asparagus. Furthermore, neither reasons why products are removed from the supply chains nor their alternative uses are fully examined yet. This is why, the study takes a look on those issues, too. Results are based on data from an online survey among producers of fruits, vegetables and potatoes in North-Rhine Westphalia, Germany and on interviews with producers and other supply chain experts. Findings suggest that the products’ size and form, their storage capabilities and food safety issues have big impacts on food losses. Despite a small sample size, these findings are in line with recent studies.
This paper aims to assess farmers’ challenges in enhancing biodiversity. The so-called “trilemma” (WBGU 2021) of land use stems from the multiple demands made on land for the benefit of mitigating climate change, securing food, and maintaining biodiversity. Agriculture is accused of maladministration, causing soil contamination, animal cruelty, bee mortality, and climate change. However, farmers play a key role in overcoming upcoming sustainability challenges. While their supportive role is urgently needed, farmers find themselves caught between a “rock” and a ”hard place”. Consumers call for sustainable production and affordable food products without pesticide residues, demanding enough for all. Farmers are restricted by the wants and needs of consumers who are influenced by interest groups and exposed to interdependent direct and indirect influencing factors. They need to balance the scrutiny of the critical public as well as the regulatory control. In this paper, we collected and surveyed the data of farmers within or close to the 21 selected nature protected areas of the DINA (Diversity of Insects in Nature protected Areas) Project, using a mixed methods approach with a semi-structured questionnaire considering issues’ interdependencies and the complexity of today´s problems. The conflicts and obstacles faced by farmers were assessed. The results reflect the farmers’ willingness and the importance of receiving appreciation for implementing biodiversity measures. These results, complemented by a following quantitative study, are the basis for recommendations for policymakers and farmers in all German nature protected areas.
Background:
Access to electricity is one of the enabling factors for healthcare service provision. From the sustainable development perspective, an essential requirement for improving health and caring for our environment is to assure that health facilities have sufficient and reliable access to the supply of clean and sustainable energy. The objective of this work is to investigate the users’ perceptions of electricity needs and electricity sources and the way those influence different attributes and their relevance for the diffusion of renewable electricity systems in healthcare facilities.
Methods:
To identify preferences and choices, Stated Choice modelling was applied as the use of solar PV systems in health facilities is not widespread in Ghana. This method allows to present the respondents with hypothetical options, which have attributes close to the real world. Four attributes were considered, namely electricity system configuration, initial investment cost, monthly costs, and improvements to the reliability of the electricity supply.
Results:
The largest share of the 200 health facilities interviewed reported services provision as outpatient treatment, provision of maternity services and family planning, which are relatively low electricity-intensive services. However, there was a general perception that increased reliability on the electricity supply can improve the health service provision and operation of the facilities. Moreover, despite that preferences towards the solar systems, the initial investment costs of the solar systems is still perceived as preventing the adoption of this technology
Conclusion:
From this study we can conclude that health facilities in Ghana rely greatly on the national supply which has issues with reliability, compromising the delivery of healthcare services. However, the adoption of alternative electricity technologies based on renewable sources is not likely to occur at the facility level without the engagement of other actors that can help bridging the barriers for adoption, as initial investment costs.
Accurate global horizontal irradiance (GHI) forecasting is critical for integrating solar energy into the power grid and operating solar power plants. The Weather Research and Forecasting model with its solar radiation extension (WRF-Solar) has been used to forecast solar irradiance in different regions around the world. However, the application of the WRF-Solar model to the prediction of GHI in West Africa, particularly Ghana, has not yet been investigated. The aim of this study is to evaluate the performance of the WRF-Solar model for predicting GHI in Ghana, focusing on three automatic weather stations (Akwatia, Kumasi and Kologo) for the year 2021. We used two one-way nested domains (D1 = 15 km and D2 = 3 km) to investigate the ability of the fully coupled WRF-Solar model to forecast GHI up to 72-hour ahead under different atmospheric conditions. The initial and lateral boundary conditions were taken from the ECMWF high-resolution operational forecasts. Our findings reveal that the WRF-Solar model performs better under clear skies than cloudy skies. Under clear skies, Kologo performed best in predicting 72-hour GHI, with a first day nRMSE of 9.62 %. However, forecasting GHI under cloudy skies at all three sites had significant uncertainties. Additionally, WRF-Solar model is able to reproduce the observed GHI diurnal cycle under high AOD conditions in most of the selected days. This study enhances the understanding of the WRF-Solar model’s capabilities and limitations for GHI forecasting in West Africa, particularly in Ghana. The findings provide valuable information for stakeholders involved in solar energy generation and grid integration towards optimized management in the region.
Accurate forecasting of solar irradiance is crucial for the integration of solar energy into the power grid, power system planning, and the operation of solar power plants. The Weather Research and Forecasting (WRF) model, with its solar radiation (WRF-Solar) extension, has been used to forecast solar irradiance in various regions worldwide. However, the application of the WRF-Solar model for global horizontal irradiance (GHI) forecasting in West Africa, specifically in Ghana, has not been studied. This study aims to evaluate the performance of the WRF-Solar model for GHI forecasting in Ghana, focusing on 3 health centers (Kologo, Kumasi and Akwatia) for the year 2021. We applied a two one-way nested domain (D1=15 km and D2=3 km) to investigate the ability of the WRF solar model to forecast GHI up to 72 hours in advance under different atmospheric conditions. The initial and lateral boundary conditions were taken from the ECMWF operational forecasts. In addition, the optical aerosol depth (AOD) data at 550 nm from the Copernicus Atmosphere Monitoring Service (CAMS) were considered. The study uses statistical metrics such as mean bias error (MBE), root mean square error (RMSE), to evaluate the performance of the WRF-Solar model with the observational data obtained from automatic weather stations in the three health centers in Ghana. The results of this study will contribute to the understanding of the capabilities and limitations of the WRF-Solar model for forecasting GHI in West Africa, particularly in Ghana, and provide valuable information for stakeholders involved in solar energy generation and grid integration towards optimized management of in the region.
Anhand detaillierter Netzanalysen für ein reales Mittelspannungsnetzgebiet konnte gezeigt werden, dass sowohl die Einbindung von Prognosedaten auf Basis von Satelliten und Wetterdaten, als auch die Verbesserung von Folgetagsprognosen auf der Basis numerischer Wettermodelle einen deutlichen Mehrwert für ein prognosebasiertes Engpassmanagement bzw. Redispatch und Blindleistungsmanagement im Verteilnetz aufweisen. Auch Kurzfristprognosen auf der Basis von Satellitendaten haben einen positiven Effekt. Ein weiterer wichtiger Mehrwert des Projektes ist auch die Rückmeldung der kritischen Prognosesituationen aus Sicht der Anwendungsfälle, so dass wie bereits im Projekt gezeigt und darüber hinaus, Prognosen zielgerichteter auf die Anwendung im Verteilnetzbetrieb ausgelegt und optimiert werden können.
Weiterhin konnten Prognoseverbesserungen für das Vorhersagemodell des Deutschen Wetterdienstes durch die Assimilation von sichtbaren Satellitenbildern erreicht werden. Darüber hinaus wurden Wolken- und Strahlungsprodukte aus Satelliten verbessert und somit die Datenbasis für die Kurzfristprognose als auch für die Assimilation.
Darüber hinaus wurden verschiedene Methoden entwickelt, die zukünftig zu einer weiteren Prognoseverbesserung, insbesondere für Wettersituationen mit hohen Prognosefehlern, führen könnten. Solche Situationen wurden aus Sicht des Netzbetriebs und mithilfe von satellitenbasierten Analysen der Gesamtwetterlage für die Perioden der MetPVNet Messkampagnen identifiziert. Hierbei handelte es sich insbesondere um Situationen mit starker oder stark wechselhafter Bewölkung.
Für die MetPVNet Messkampagnen wurde auf der Basis eines Trainingsdatensatzes und in Abhängigkeit der Variabilitätsklasse die Abweichung der bodennahen Einstrahlung von Satellitendaten oder von Strahlungsprognosen quantifiziert. Diese Art der Informationen bietet zukünftig die Möglichkeit zur Bewertung der Prognosegüte.
Solar energy is one option to serve the rising global energy demand with low environmental Impact [1]. Building an energy system with a considerable share of solar power requires long-term investment and a careful investigation of potential sites. Therefore, understanding the impacts from varying regionally and locally determined meteorological conditions on solar energy production will influence energy yield projections. Clouds are moving on a short term timescale and have a high influence on the available solar radiation, as they absorb, reflect and scatter parts of the incoming light [2]. However, modeling photovoltaic (PV) power yields with a spectral resolution and local cloud information gives new insights on the atmospheric impact on solar energy.
The accurate forecasting of solar radiation plays an important role for predictive control applications for energy systems with a high share of photovoltaic (PV) energy. Especially off-grid microgrid applications using predictive control applications can benefit from forecasts with a high temporal resolution to address sudden fluctuations of PV-power. However, cloud formation processes and movements are subject to ongoing research. For now-casting applications, all-sky-imagers (ASI) are used to offer an appropriate forecasting for aforementioned application. Recent research aims to achieve these forecasts via deep learning approaches, either as an image segmentation task to generate a DNI forecast through a cloud vectoring approach to translate the DNI to a GHI with ground-based measurement (Fabel et al., 2022; Nouri et al., 2021), or as an end-to-end regression task to generate a GHI forecast directly from the images (Paletta et al., 2021; Yang et al., 2021). While end-to-end regression might be the more attractive approach for off-grid scenarios, literature reports increased performance compared to smart-persistence but do not show satisfactory forecasting patterns (Paletta et al., 2021). This work takes a step back and investigates the possibility to translate ASI-images to current GHI to deploy the neural network as a feature extractor. An ImageNet pre-trained deep learning model is used to achieve such translation on an openly available dataset by the University of California San Diego (Pedro et al., 2019). The images and measurements were collected in Folsom, California. Results show that the neural network can successfully translate ASI-images to GHI for a variety of cloud situations without the need of any external variables. Extending the neural network to a forecasting task also shows promising forecasting patterns, which shows that the neural network extracts both temporal and momentarily features within the images to generate GHI forecasts.
Ziel der vorliegenden Forschungsarbeit ist es, den Einfluss von Persönlichkeit auf nachhaltige Maßnahmen anhand des Streamingkonsums zu eruieren. Der allgemein steigende Streamingkonsum und die damit einhergehenden Umweltschäden einerseits und ein wachsendes gesellschaftliches Umweltbewusstsein andererseits stellen einen Widerspruch dar. An einer Online-Umfrage zu diesen und weiterführenden Aspekten nahmen 204 Probanden teil. Während sich die Eigenschaften Verträglichkeit und Offenheit in hoher Ausprägung positiv auf die Umwelteinstellung, das Umweltverhalten und die Umweltbesorgnis auswirkten, wurden die umweltfreundlichen Maßnahmen in einer Clusteranalyse hingegen stärker von der Gruppe bevorzugt, deren Verträglichkeit und Offenheit verhältnismäßig schwach ausgeprägt waren. Ein geringes Wissen über die streamingbedingten Umweltfolgen lag grundsätzlich vor und dient als möglicher Erklärungsansatz des genannten Widerspruchs. Die Probanden forderten, ein Bewusstsein für diese Thematik zu schaffen. Um Streamingkonsum umweltfreundlicher zu gestalten empfiehlt es sich, alle am Prozess beteiligten Akteure einzubeziehen. Die befragten Konsumenten bevorzugten dabei vor allem die Verwendung von Ökostrom und lehnten eine Umstellung der Bezahlstruktur vorwiegend ab.
Zur Milderung des Klimawandels sind Maßnahmen zur Förderung von Energieeinsparungen notwendig. Energiespartipps informieren über energiesparende Verhaltensweisen und Produkte. Zur Formulierung wirkungsvoller Energiespartipps untersucht die Arbeit, welchen Einfluss Ergänzungen von CO2-Angaben und Formulierungen der Konsequenzen auf die wahrgenommene Informationsqualität, Nützlichkeit und Verhaltensabsicht haben. Außerdem wird untersucht, ob es diesbezüglich Unterschiede zwischen verhaltens- und investitionsorientierten Tipps gibt. Dazu wurde ein Onlineexperiment (N = 352) im 4 x 4 x 2 Design mit den vierstufigen Zwischensubjektfaktoren Framing der Währung (alleinige CO2-Angabe, Jahresvergleichswert, äquivalente Fahrstrecke, äquivalente Laptopnutzung) und Framing der Konsequenz (erreichte Einsparung, vermiedener Ausstoß, entgangene Einsparung, verursachter Ausstoß) sowie der Art des Energiespartipps (verhaltens- vs. investitionsorientiert) als zweistufigen Innersubjektfaktor konzipiert. Varianzanalysen ergaben, dass der verhaltensorientierte Tipp positiver als der investitionsorientierte Tipp bewertet wurde und verhaltensnahe Ergänzungen die Nützlichkeit von CO2-Angaben sowie die Verhaltensintention erhöhen. Das Framing der Konsequenz hatte keinen Effekt. Die Ergebnisse zeigen die Relevanz, zwischen verhaltens- und investitionsorientierten Energiespartipps zu differenzieren und verhaltensnahe Ergänzungen von CO2-Angaben in Kilogramm zu berücksichtigen.
For several decades, farmers have been mixing rock powders with livestock slurry to reduce its NH3 emissions and increase its nutrient content. However, mixing rock powders with slurry is controversial, and there is currently no scientific evidence for its effects on NH3 and greenhouse gas (GHG) emissions or on changes in its nutrient content due to element release from rock powders. The major aim of this study was therefore to analyse the effects of mixing two commercially established rock powders with cattle slurry on NH3, CO2, N2O and CH4 emissions, and on nutrient release over a course of 46 days. We found that rock powders did not significantly affect CO2 emission rates. NH3 and N2O emission rates did not differ significantly up until the end of the trial, when the emission rates of the rock powder treatments significantly increased for NH3 and significantly decreased for N2O, respectively, which coincided with a reduction of the slurry crust. Cumulative NH3 emissions did not, however, differ significantly between treatments. Unexpected and significant increases in CH4 emission rates occurred for the rock powder treatments. Rock powders increased the macro- and micronutrient content of the slurry. The conflicting results are discussed and future research directions are proposed.
Education for Sustainable Development (ESD, SDG 4) and human well-being (SDG 3) are among the central subjects of the Sustainable Development Goals (SDGs). In this article, based on the Questionnaire for Eudaimonic Well-Being (QEWB), we investigate to what extent (a) there is a connection between EWB and practical commitment to the SDGs and whether (b) there is a deficit in EWB among young people in general. We also want to use the article to draw attention to the need for further research on the links between human well-being and commitment for sustainable development. A total of 114 students between the ages of 18 and 34, who are either engaged in (extra)curricular activities of sustainable development (28 students) or not (86 students), completed the QEWB. The students were interviewed twice: once regarding their current and their aspired EWB. Our results show that students who are actively engaged in activities for sustainable development report a higher EWB than non-active students. Furthermore, we show that students generally report deficits in EWB and wish for an improvement in their well-being. This especially applies to aspects of EWB related to self-discovery and the sense of meaning in life. Our study suggests that a practice-oriented ESD in particular can have a positive effect on the quality of life of young students and can support them in working on deficits in EWB.
Als weltweit anspruchsvollstes Umweltmanagementsystem trägt EMAS auf Unternehmensebene als Baustein zur Nachhaltigen Entwicklung bei. EMAS ist ein Instrument der Europäischen Union, an dem Organisationen, unabhängig von ihrer Größe und Branche, weltweit auf freiwilliger Basis teilnehmen können. Die geplante EMAS-Validierung der UN-Klimakonferenz (COP 23) in Bonn (06. – 17.11.2017), hat das Interesse der Projektkoordination von „Sustainable Bonn – Konferenzort der Nachhaltigkeit“ geweckt, die EMAS-Einführung bei deren Projektteilnehmern untersuchen zu lassen. Daher liegt der Branchenfokus auf dem Gastgewerbe, aus denen die derzeitigen Teilnehmer des Bonner Projekts überwiegend stammen. Um Branchenspezifika bei EMAS besser zu berücksichtigen hat die Europäische Kommission im April 2016 hat ein Referenzdokument über bewährte Umweltmanagementpraktiken zur Steigerung der Öko-Effektivität mit einschlägigen Indikatoren zur Messung der Umweltleistung mit Richtwerten für die Tourismusbranche veröffentlicht, die im Rahmen einer EMAS-Einführung unter anderem von Gastgewerbebetrieben berücksichtigt werden müssen.
The temperature of photovoltaic modules is modelled as a dynamic function of ambient temperature, shortwave and longwave irradiance and wind speed, in order to allow for a more accurate characterisation of their efficiency. A simple dynamic thermal model is developed by extending an existing parametric steady-state model using an exponential smoothing kernel to include the effect of the heat capacity of the system. The four parameters of the model are fitted to measured data from three photovoltaic systems in the Allgäu region in Germany using non-linear optimisation. The dynamic model reduces the root-mean-square error between measured and modelled module temperature to 1.58 K on average, compared to 3.03 K for the steady-state model, whereas the maximum instantaneous error is reduced from 20.02 to 6.58 K.
Diversity of Insects in Nature protected Areas (DINA): an interdisciplinary German research project
(2021)
Insect declines and biodiversity loss have attracted much attention in recent years, but lack of comprehensive data, conflicting interests among stakeholders and insufficient policy guidance hinder progress in preserving biodiversity. The project DINA (Diversity of Insects in Nature protected Areas) investigates insect communities in 21 nature reserves in Germany. All selected conservation sites border arable land, with agricultural practices assumed to influence insect populations. We taught citizen scientists how to manage Malaise traps for insect collection, and subsequently used a DNA metabarcoding approach for species identification. Vegetation surveys, plant metabarcoding as well as geospatial and ecotoxicological analyses will help to unravel contributing factors for the deterioration of insect communities. As a pioneering research project in this field, DINA includes a transdisciplinary dialogue involving relevant stakeholders such as local authorities, policymakers, and farmers, which aims at a shared understanding of conservation goals and action pathways. Stakeholder engagement combined with scientific results will support the development of sound policy recommendations to improve legal frameworks, landscape planning, land use, and conservation strategies. With this transdisciplinary approach, we aim to provide the background knowledge to implement policy strategies that will halt further decline of insects in German protected areas.
In the research project "MetPVNet", both, the forecast-based operation management in distribution grids and as well as the forecasts of the feed-in of PV-power from decentralized plants could be improved on the basis of satellite data and numerical weather forecasts. Based on a detailed network analyses for a real medium-voltage grid area, it was shown that both – the integration of forecast data based on satellite and weather data and the improvement of subsequent day forecasts based on numerical weather models – have a significant added value for forecast-based congestion management or redispatch and reactive power management in the distribution grid. Furthermore, forecast improvements for the forecast model of the German Weather Service were achieved by assimilating visible satellite imagery, and cloud and radiation products from satellites were improved, thus improving the database for short-term forecasting as well as for assimilation. In addition, several methods have been developed that will enable forecast improvement in the future, especially for weather situations with high cloud induced variability and high forecast errors. This article summarizes the most important project results.
Unsachgemäß entsorgte Zigarettenkippen stellen aufgrund der in ihnen enthaltenen Giftstoffe ein relevantes, ökologisches Problem dar. Diese Forschungsarbeit untersucht den Einsatz von Nudging zur Bekämpfung der Problematik. In einer quantiativen Online-Befragung wurden zunächst die Gründe für das umweltschädliche Verhalten untersucht (N = 96). Hierbei konnte die Gegenwartstendenz von Personen als statistisch signifikanter Hauptgrund ermittelt werden. Viele Personen gaben an, die langfristigen ökologischen Kosten einer unsachgemäßen Entsorgung aufgrund des kurzfristigen persönlichen Nutzens zu ignorieren. Dieser entsteht durch die Gemütlichkeit des „Wegschnipsens“ einer Zigarettenkippe. Im Anschluss wurde ein auf die Gegenwartstendenz von Personen fokussierter Nudge entwickelt und in einem Feldexperiment auf seine Wirksamkeit überprüft, indem die Relation von unsachgemäß zu sachgemäß entsorgten Zigarettenkippen vor und nach dem Einsatz des Nudges dokumentiert wurde. Ohne Einsatz des Nudges (N = 92) wurden am Erhebungsort 64.1 Prozent und mit Einsatz des Nudges (N = 142) lediglich 38.0 Prozent der Zigarettenkippen unsachgemäß entsorgt. In dem Feldexperiment konnte der Nudge effektiv zur Förderung von nachhaltigem Verhalten eingesetzt werden.
Ghana suffers from frequent power outages, which can be compensated by off-grid energy solutions. Photovoltaic-hybrid systems become more and more important for rural electrification due to their potential to offer a clean and cost-effective energy supply. However, uncertainties related to the prediction of electrical loads and solar irradiance result in inefficient system control and can lead to an unstable electricity supply, which is vital for the high reliability required for applications within the health sector. Model predictive control (MPC) algorithms present a viable option to tackle those uncertainties compared to rule-based methods, but strongly rely on the quality of the forecasts. This study tests and evaluates (a) a seasonal autoregressive integrated moving average (SARIMA) algorithm, (b) an incremental linear regression (ILR) algorithm, (c) a long short-term memory (LSTM) model, and (d) a customized statistical approach for electrical load forecasting on real load data of a Ghanaian health facility, considering initially limited knowledge of load and pattern changes through the implementation of incremental learning. The correlation of the electrical load with exogenous variables was determined to map out possible enhancements within the algorithms. Results show that all algorithms show high accuracies with a median normalized root mean square error (nRMSE) <0.1 and differing robustness towards load-shifting events, gradients, and noise. While the SARIMA algorithm and the linear regression model show extreme error outliers of nRMSE >1, methods via the LSTM model and the customized statistical approaches perform better with a median nRMSE of 0.061 and stable error distribution with a maximum nRMSE of <0.255. The conclusion of this study is a favoring towards the LSTM model and the statistical approach, with regard to MPC applications within photovoltaic-hybrid system solutions in the Ghanaian health sector.
Im Projekt wurde anhand medienanalytischer Verfahren, Befragungen und Experimenten untersucht, wie sich Verbrauchergruppen über das Thema Tierwohl informieren und welche Argumente die Diskussion bestimmen. Die Ergebnisse zeigen: Insgesamt herrscht eine positive Einstellung zu Tierwohl-Initiativen; finanzielle Aspekte sind ein zentrales Thema. Mehr Transparenz bei den Kosten wäre wünschenswert. Das Internet kann dies unterstützen. Aber nicht alle Zielgruppen werden damit erreicht.
Hydrogen is a versatile energy carrier. When produced with renewable energy by water splitting, it is a carbon neutral alternative to fossil fuels. The industrialization process of this technology is currently dominated by electrolyzers powered by solar or wind energy. For small scale applications, however, more integrated device designs for water splitting using solar energy might optimize hydrogen production due to lower balance of system costs and a smarter thermal management. Such devices offer the opportunity to thermally couple the solar cell and the electrochemical compartment. In this way, heat losses in the absorber can be turned into an efficiency boost for the device via simultaneously enhancing the catalytic performance of the water splitting reactions, cooling the absorber, and decreasing the ohmic losses.[1,2] However,integrated devices (sometimes also referred to as “artificial leaves”), currently suffer from a lower technology readiness level (TRL) than the completely decoupled approach.
The aim of this paper is to assess the objectives of farmers’ challenges in enhancing biodiversity. The so-called “trilemma” (WBGU 2021) of land use stems from the multiple demands made on land for the benefit of mitigating climate change, securing food and maintaining biodiversity. The agricultural sector is accused of maladministration: it is blamed for causing soil contamination, animal cruelty, bee mortality and climate change. That is why farmers are seen as key actors at all levels. They are, however, also key players when it comes to overcoming the problems of the future. Their supportive role is urgently needed, but farmers find themselves caught between a “rock” and a ”hard place”. Consumers are calling for sustainable, environmentally friendly production and inexpensive food products that do not contain pesticide residues, demanding enough food for all. Farmers are restricted by the wants and needs of consumers who are influenced by interest groups and are exposed to direct and indirect influencing factors and their interdependencies. They are also tasked with balancing the scrutiny of the critical public on the one hand, and the control exercised by eager authorities on the other.
As part of the DINA (Diversity of Insects in Nature protected Areas) project, a trans- and interdisciplinary research study, we collected and surveyed the data of farmers who are farming within or close to the 21 selected nature protected areas included in the DINA project. Data was collected as part of a mixed method approach using a semi-structured questionnaire. The methodological and strategic approach and interdependencies of issues demonstrate the complexity of today’s problems. To investigate this, we first used the data collection method using questionnaires with closed and open questions. The conflicts and obstacles farmers face were evaluated, and the results show farmers’ willingness and the importance of appreciation shown to farmers for implementation of biodiversity measures. The paper proposes some follow-up activities (quantitative study) to verify the objectives. The results will later lead to recommendations for policymakers and farmers in all German nature protected areas.
The implementation of the Sustainable Development Goals (SDGs) and the conservation and protection of nature are among the greatest challenges facing urban regions. There are few approaches so far that link the SDGs to natural diversity and related ecosystem services at the local level and track them in terms of increasing sustainable development at the local level. We want to close this gap by developing a set of indicators that capture ecosystem services in the sense of the SDGs and which are based on data that are freely available throughout Germany and Europe. Based on 10 SDGs and 35 SDG indicators, we are developing an ecosystem service and biodiversity-related indicator set for the evaluation of sustainable development in urban areas. We further show that it is possible to close many of the data gaps between SDGs and locally collected data mentioned in the literature and to translate the universal SDGs to the local level. Our example develops this set of indicators for the Bonn/Rhein-Sieg metropolitan area in North Rhine-Westphalia, Germany, which comprises both rural and densely populated settlements. This set of indicators can also help improve communication and plan sustainable development by increasing transparency in local sustainability, implementing a visible sustainability monitoring system, and strengthening the collaboration between local stakeholders.
Die vorliegende Forschungsarbeit setzt sich mit nachhaltigem Verhalten in Bezug auf die Nutzung von Kaffeebehältern an der HBRS auseinander. Anlass dafür ist, dass Pappbecher aufgrund einer Plastikbeschichtung nur schwer recycelbar sind und somit die Umwelt erheblich beeinträchtigen. In diesem Zusammenhang nahmen 204 Studierende an einer Online-Befragung teil. Den Ergebnissen zufolge kommen derzeit vor allem Einweg-Pappbecher zum Einsatz. Zur Modifizierung dieses umweltschädlichen Verhaltens bedarf es an geeigneten Interventionsstrategien. Basierend auf den Ergebnissen sind Maßnahmen zu implementieren, die dem Defizit an Handlungswissen und dem hohen Aufwand entgegenwirken, welcher mit der Verwendung eigens mitgebrachter Becher und den vorhandenen Porzellantassen assoziiert wird. Nach Sicherstellung der ökologischen Vorteile und finanziellen Umsetzbarkeit sollte das bestehende Pfandsystem um praktischere Becher sowie flexible Rückgabemöglichkeiten erweitert werden. Unterstützend ist eine Belohnung in Form von Freigetränken oder einem geringen finanziellen Rabatt sinnvoll, um den automatischen Verbrauch von Pappbechern zu unterbinden.
Neueste Funde in Südafrika haben nochmals unterstrichen, dass die ältesten Menschen der Welt offensichtlich aus Afrika abstammen. Somit kommt diesem Kontinent historisch gesehen ganz besondere Bedeutung zu. Allerdings war seine Geschichte in der jüngeren Zeit, insbesondere ab Mitte des 19. Jahrhunderts, von der Kolonialisierung durch europäische Staaten stark geprägt. Viele tiefe Wunden aus der damaligen Zeit haben noch heute Auswirkungen auf die Gesellschaft insgesamt. Allerdings ist der Kontinent derzeit auch mit einer größeren Zahl anders gelagerter Herausforderungen konfrontiert.
Zum einen versucht Afrika mittels einer Anzahl von Regionalorganisationen sowie der Afrikanischen Union als global agierender Institution den inneren Zusammenhalt zu stärken, zum anderen ist der Kontinent über die letzten Jahrzehnte bis in die jüngste Gegenwart durch politische und militärische Konflikte zwischen Nachbarstaaten geprägt. Hinzu kommen regelmäßig innere gesellschaftliche Umwälzungen einzelner Länder durch einen gewaltsamen oder manipulierten politischen Wechsel.
Dabei könnte der Kontinent sich durchaus auf einem guten Entwicklungspfad befinden, verfügt er doch – auch im Vergleich zu anderen Kontinenten – über eine Vielzahl von wichtigen Rohstoffen. Allerdings profitieren die einzelnen afrikanischen Staaten – und insbesondere ihre Bürgerinnen und Bürger - hiervon oft nicht in einem angemessenen Rahmen. Somit ergibt sich in großen Teilen des Kontinents ein soziales Ungleichgewicht, das zu erheblichen inneren Spannungen führt. Erschwerend kommt hinzu, dass Afrika weltweit am stärksten vom Klimawandel betroffen ist.
Bei näherer Betrachtung der z.T. sehr unterschiedlichen wirtschaftlichen, politischen und sozialen Situation des großen Kontinents (Datenerhebung bis Ende Juni 2023) führt die vorliegende Untersuchung zu einer insgesamt überwiegend kritischen Einschätzung hinsichtlich der weiteren Entwicklung Afrikas, die im Schlusskapitel bzgl. der absehbaren Konsequenzen für den Kontinent näher dargelegt wird.
Recent findings in South Africa have once again underlined the fact that the oldest people in the world obviously came from Africa. Thus, historically, this continent has a very special significance. However, its history in more recent times, especially from the mid-19th century onwards, was strongly influenced by colonisation by European states. Many deep wounds from that time still have an impact on society as a whole today. However, the continent is currently also confronted with a greater number of challenges of a different nature.
On the one hand, Africa is trying to strengthen internal cohesion by means of a number of regional organisations and the African Union as a globally active institution; on the other hand, the continent has been marked by political and military conflicts between neighbouring states over the past decades until the recent present. In addition, there are regular internal social upheavals in individual countries due to violent or manipulated political change.
Yet the continent could well be on a good development path, since it has a large number of important raw materials - also in comparison to other continents. However, the individual African states - and especially their citizens - often do not benefit from this to an adequate extent. This results in a social imbalance in large parts of the continent (data collection until the end of June 2023), which leads to considerable internal tensions. To make matters worse, Africa is the continent most affected by climate change.
A closer look at the partly very different economic, political and social situations of the large continent leads to an overall predominantly critical assessment of Africa's further development, which is explained in more detail in the final chapter with regard to the foreseeable consequences for the continent.
The clear-sky radiative effect of aerosol–radiation interactions is of relevance for our understanding of the climate system. The influence of aerosol on the surface energy budget is of high interest for the renewable energy sector. In this study, the radiative effect is investigated in particular with respect to seasonal and regional variations for the region of Germany and the year 2015 at the surface and top of atmosphere using two complementary approaches.
First, an ensemble of clear-sky models which explicitly consider aerosols is utilized to retrieve the aerosol optical depth and the surface direct radiative effect of aerosols by means of a clear-sky fitting technique. For this, short-wave broadband irradiance measurements in the absence of clouds are used as a basis. A clear-sky detection algorithm is used to identify cloud-free observations. Considered are measurements of the short-wave broadband global and diffuse horizontal irradiance with shaded and unshaded pyranometers at 25 stations across Germany within the observational network of the German Weather Service (DWD). The clear-sky models used are the Modified MAC model (MMAC), the Meteorological Radiation Model (MRM) v6.1, the Meteorological–Statistical solar radiation model (METSTAT), the European Solar Radiation Atlas (ESRA), Heliosat-1, the Center for Environment and Man solar radiation model (CEM), and the simplified Solis model. The definition of aerosol and atmospheric characteristics of the models are examined in detail for their suitability for this approach.
Second, the radiative effect is estimated using explicit radiative transfer simulations with inputs on the meteorological state of the atmosphere, trace gases and aerosol from the Copernicus Atmosphere Monitoring Service (CAMS) reanalysis. The aerosol optical properties (aerosol optical depth, Ångström exponent, single scattering albedo and asymmetry parameter) are first evaluated with AERONET direct sun and inversion products. The largest inconsistency is found for the aerosol absorption, which is overestimated by about 0.03 or about 30 % by the CAMS reanalysis. Compared to the DWD observational network, the simulated global, direct and diffuse irradiances show reasonable agreement within the measurement uncertainty. The radiative kernel method is used to estimate the resulting uncertainty and bias of the simulated direct radiative effect. The uncertainty is estimated to −1.5 ± 7.7 and 0.6 ± 3.5 W m−2 at the surface and top of atmosphere, respectively, while the annual-mean biases at the surface, top of atmosphere and total atmosphere are −10.6, −6.5 and 4.1 W m−2, respectively.
The retrieval of the aerosol radiative effect with the clear-sky models shows a high level of agreement with the radiative transfer simulations, with an RMSE of 5.8 W m−2 and a correlation of 0.75. The annual mean of the REari at the surface for the 25 DWD stations shows a value of −12.8 ± 5 W m−2 as the average over the clear-sky models, compared to −11 W m−2 from the radiative transfer simulations. Since all models assume a fixed aerosol characterization, the annual cycle of the aerosol radiation effect cannot be reproduced. Out of this set of clear-sky models, the largest level of agreement is shown by the ESRA and MRM v6.1 models.
The clear-sky radiative effect of aerosol-radiation interactions is of relevance for our understanding of the climate system. The influence of aerosol on the surface energy budget is of high interest for the renewable energy sector. In this study, the radiative effect is investigated in particular with respect to seasonal and regional variations for the region of Germany and the year 2015 at the surface and top of atmosphere using two complementary approaches.
First, an ensemble of clear-sky models which explicitly consider aerosols is utilized to retrieve the aerosol optical depth and the surface direct radiative effect of aerosols by means of a clear sky fitting technique. For this, short-wave broadband irradiance measurements in the absence of clouds are used as a basis. A clear sky detection algorithm is used to identify cloud free observations. Considered are measurements of the shortwave broadband global and diffuse horizontal irradiance with shaded and unshaded pyranometers at 25 stations across Germany within the observational network of the German Weather Service (DWD). Clear sky models used are MMAC, MRMv6.1, METSTAT, ESRA, Heliosat-1, CEM and the simplified Solis model. The definition of aerosol and atmospheric characteristics of the models are examined in detail for their suitability for this approach.
Second, the radiative effect is estimated using explicit radiative transfer simulations with inputs on the meteorological state of the atmosphere, trace-gases and aerosol from CAMS reanalysis. The aerosol optical properties (aerosol optical depth, Ångström exponent, single scattering albedo and assymetrie parameter) are first evaluated with AERONET direct sun and inversion products. The largest inconsistency is found for the aerosol absorption, which is overestimated by about 0.03 or about 30 % by the CAMS reanalysis. Compared to the DWD observational network, the simulated global, direct and diffuse irradiances show reasonable agreement within the measurement uncertainty. The radiative kernel method is used to estimate the resulting uncertainty and bias of the simulated direct radiative effect. The uncertainty is estimated to −1.5 ± 7.7 and 0.6 ± 3.5 W m−2 at the surface and top of atmosphere, respectively, while the annual-mean biases at the surface, top of atmosphere and total atmosphere are −10.6, −6.5 and 4.1 W m−2, respectively.
The retrieval of the aerosol radiative effect with the clear sky models shows a high level of agreement with the radiative transfer simulations, with an RMSE of 5.8 W m−2 and a correlation of 0.75. The annual mean of the REari at the surface for the 25 DWD stations shows a value of −12.8 ± 5 W m−2 as average over the clear sky models, compared to −11 W m−2 from the radiative transfer simulations. Since all models assume a fixed aerosol characterisation, the annual cycle of the aerosol radiation effect cannot be reproduced. Out of this set of clear sky models, the largest level of agreement is shown by the ESRA and MRMv6.1 models.