Combined impacts of climate and air pollution on human health and agricultural productivity

Climate change and air pollution can interact to amplify risks to human health and crop production. This has significant implications for our ability to reach the Sustainable Development Goals (e.g. SDGs 2, 3, 13, 15) and for the design of effective mitigation and adaptation policies and risk management. To be able to achieve the SDG targets, closer integration of climate change and air pollution both in terms of impact assessment for human health and agricultural productivity and respective policy development is needed. Currently, studies estimating the impacts of climate and air pollutants on human health and crops mostly treat these stressors separately, and the methods used by the health and agricultural science communities differ. Better insights into the methods applied in the different communities can help to improve existing and develop new methods to advance our knowledge about the combined impacts of climate change and air pollution on human health and crops. This topical review provides an overview of current methodologies applied in the two fields of human health and agricultural crop impact studies, ranging from empirical regression-based and experimental methods to more complex process-based models. The latter are reasonably well developed for estimating impacts on agricultural crops, but not for health impacts. We review available literature addressing the combined effects of climate and air pollution on human health or agricultural productivity to provide insights regarding state-of-the-art knowledge and currently available methods in the two fields. Challenges to assess the combined effect of climate and air pollution on human health and crops, and opportunities for both fields to learn from each other, are discussed

Evaluation of simulated ozone effects in forest ecosystems against biomass damage estimates from fumigation experiments

Regional estimates of the effects of ozone pollution on forest growth depend on the availability of reliable injury functions that estimate a representative ecosystem response to ozone exposure. A number of such injury functions for forest tree species and forest functional types have recently been published and subsequently applied in terrestrial biosphere models to estimate regional or global effects of ozone on forest tree productivity and carbon storage in the living plant biomass. The resulting impacts estimated by these biosphere models show large uncertainty in the magnitude of ozone effects predicted. To understand the role that these injury functions play in determining the variability in estimated ozone impacts, we use the O-CN biosphere model to provide a standardised modelling framework. We test four published injury functions describing the leaf-level, photosynthetic response to ozone exposure (targeting the maximum carboxylation capacity of Rubisco (V$_{cmax}$) or net photosynthesis) in terms of their simulated whole-tree biomass responses against data from 23 ozone filtration/fumigation experiments conducted with young trees from European tree species at sites across Europe with a range of climatic conditions. Our results show that none of these previously published injury functions lead to simulated whole-tree biomass reductions in agreement with the observed dose–response relationships derived from these field experiments and instead lead to significant over- or underestimations of the ozone effect. By re-parameterising these photosynthetically based injury functions, we develop linear, plant-functional-typespecific dose–response relationships, which provide accurate simulations of the observed whole-tree biomass response across these 23 experiments

Mapping regional risks from climate change for rainfed rice cultivation in India

Global warming is predicted to increase in the future, with detrimental consequences for rainfed crops that are dependent on natural rainfall (i.e. non-irrigated). Given that many crops grown under rainfed conditions support the livelihoods of low-income farmers, it is important to highlight the vulnerability of rainfed areas to climate change in order to anticipate potential risks to food security. In this paper, we focus on India, where ~ 50% of rice is grown under rainfed conditions, and we employ statistical models (climate envelope models (CEMs) and boosted regression trees (BRTs)) to map changes in climate suitability for rainfed rice cultivation at a regional level (~ 18 × 18 km cell resolution) under projected future (2050) climate change (IPCC RCPs 2.6 and 8.5, using three GCMs: BCC-CSM1.1, MIROC-ESM-CHEM, and HadGEM2-ES). We quantify the occurrence of rice (whether or not rainfed rice is commonly grown, using CEMs) and rice extent (area under cultivation, using BRTs) during the summer monsoon in relation to four climate variables that affect rice growth and yield namely ratio of precipitation to evapotranspiration (PER), maximum and minimum temperatures (Tmax and Tmin), and total rainfall during harvesting. Our models described the occurrence and extent of rice very well (CEMs for occurrence, ensemble AUC = 0.92; BRTs for extent, Pearson's r = 0.87). PER was the most important predictor of rainfed rice occurrence, and it was positively related to rainfed rice area, but all four climate variables were important for determining the extent of rice cultivation. Our models project that 15%–40% of current rainfed rice growing areas will be at risk (i.e. decline in climate suitability or become completely unsuitable). However, our models project considerable variation across India in the impact of future climate change: eastern and northern India are the locations most at risk, but parts of central and western India may benefit from increased precipitation. Hence our CEM and BRT models agree on the locations most at risk, but there is less consensus about the degree of risk at these locations. Our results help to identify locations where livelihoods of low-income farmers and regional food security may be threatened in the next few decades by climate changes. The use of more drought-resilient rice varieties and better irrigation infrastructure in these regions may help to reduce these impacts and reduce the vulnerability of farmers dependent on rainfed cropping

Einflüsse von Wetterextremen auf die Landwirtschaft: Eine globale Bewertung

Einflüsse von Wetterextremen auf die Landwirtschaft - Eine globale Bewertung: Der Großteil aller agro-ökologischen Zonen der Erde ist in den letzten Jahrzehnten immer wieder und in zunehmendem Maße Wetterextremen, wie zum Beispiel Dürren, Überflutungen, Hitze- und Kältewellen oder Orkanen, ausgesetzt gewesen. Laut neuester modellgestützter Berechnungen wird sich dieser Trend auf absehbare Zeit fortsetzen. Die entsprechenden Auswirkungen auf die landwirtschaftliche Produktion variieren stark, je nach Art und Ausmaß (räumlich und zeitlich) des meteorologischen Extremereignisses, der Art und Prädisposition des jeweiligen Agrarökosystems sowie der Spezies, Varietät und des Entwicklungsstadiums betroffener Nutzpflanzen. Der Umfang einhergehender monetärer Verluste und ihrer Bedeutsamkeit für die betroffene Agrarbevölkerung ist bedingt vom individuellen sozioökonomischem Status, der Ausprägung volkswirtschaftlicher Instrumente (z.B. Versicherungen, Subventionen) und der Elastizität des Marktes. Dieser Artikel gibt einen kondensierten aber facettenreichen Überblick über die globale Relevanz der Auswirkungen von Wetterextremen auf den Agrarsektor und zeigt Strategien für die zukünftige Bewältigung dieser Problematik auf. Weather extremes and their impacts on agriculture - A global appraisal: During the last decades, the majority of all agro-ecological zones on earth have been repeatedly and increasingly affected by weather extremes such as droughts, floods, heat waves, cold spells and hurricanes. According to latest model-based forecasts, this trend will persist for the foreseeable future. Respective impacts on the agricultural production vary strongly depending on the type and scale (spatially and temporally) of the weather extreme, the type and predisposition of the respective agro-ecosystem and the species, cultivar and development stage of the affected crop. The extent of the monetary loss and its significance for the concerned farming population is determined by the individual socio-economic status, the availability of financial services such as insurance schemes or subsidies, and the elasticity of the market. This article aims at giving a condensed but multifaceted overview of the global relevance of the effects of weather extremes on the agricultural sector and presents strategies how to tackle these challenges in the near future

Reaching out? Governing weather and climate services (WCS) for farmers

High-quality weather and climate services (WCS) can be critical for communicating knowledge about current and future weather and climate risks for adaptation and disaster risk management in the agricultural sector. This paper investigates the structure and performance of weather and climate services for farmers from a governance perspective. Empirically the paper compares the institutional design and operations of agro-meteorological services in Maharashtra/India and Norway through a ‘most different case study’ approach. The two cases were selected to represent great diversity in location, scale and institutional design. A governance approach based on semi-direct interviews and policy and institutional analysis was combined with local survey data of farmers’ perceptions and use of the services. Despite the fact that the context for the two agromet advisory services was very different from a climate-weather, eco-agriculture, and socio-institutional angle, the analysis reveals great similarities in the services structures and critical governance challenges. In both countries the agromet services communicated knowledge that was largely perceived not to be well tailored to farmers’ needs for decisions in specific crops- and farm operations, spatially too coarse to address local issues, and, often unreliable or inaccurate in terms of the quality of data. Farmers did, however, respond positively to specific and locally relevant information on e.g., warnings about high rainfall and spread of pests. Observing such similarities across very diverse contexts enhances the generalization potential, precisely because they evolved under very different circumstances. Similar observations find support in the wider WCS literature. Based on the empirical findings, we propose a more deliberate approach to institutional design of WCS in order to enhance governance performance and co-creation of the services at local, district and national scales. It is suggested that greater participation of farmers and agricultural extension agents in the co-creation of these services is a necessary means of improving the services, supported by the WCS literature. However, we insist that greater participation is only likely to materialize if the deficiencies in institutional design and knowledge quality and relevance are addressed to greater extent than done today. The comparison between the two services shows that Norway can learn from India that a more ambitious scope and multiple forms of communication, including the use of social media/WhatsApp groups, can facilitate greater awareness and interest among farmers in multi-purpose agromet services for multi-way communication. India can learn from Norway that a more integrated and decentralized institutional design can strengthen the network attributes of the services, foster co-creation, and improve participation of both poor and large-scale farmers and extension agents

Combined impacts of climate and air pollution on human health and agricultural productivity

Climate change and air pollution can interact to amplify risks to human health and crop production. This has significant implications for our ability to reach the Sustainable Development Goals (e.g. SDGs 2, 3, 13, 15) and for the design of effective mitigation and adaptation policies and risk management. To be able to achieve the SDG targets, closer integration of climate change and air pollution both in terms of impact assessment for human health and agricultural productivity and respective policy development is needed. Currently, studies estimating the impacts of climate and air pollutants on human health and crops mostly treat these stressors separately, and the methods used by the health and agricultural science communities differ. Better insights into the methods applied in the different communities can help to improve existing and develop new methods to advance our knowledge about the combined impacts of climate change and air pollution on human health and crops. This topical review provides an overview of current methodologies applied in the two fields of human health and agricultural crop impact studies, ranging from empirical regression-based and experimental methods to more complex process-based models. The latter are reasonably well developed for estimating impacts on agricultural crops, but not for health impacts. We review available literature addressing the combined effects of climate and air pollution on human health or agricultural productivity to provide insights regarding state-of-the-art knowledge and currently available methods in the two fields. Challenges to assess the combined effect of climate and air pollution on human health and crops, and opportunities for both fields to learn from each other, are discussed

Assessing the costs of ozone pollution in India for wheat producers, consumers, and government food welfare policies

We assess wheat yield losses occurring due to ozone pollution in India and its economic burden on producers, consumers, and the government. Applying an ozone flux–based risk assessment, we show that ambient ozone levels caused a mean 14.18% reduction in wheat yields during 2008 to 2012. Furthermore, irrigated wheat was particularly sensitive to ozone-induced yield losses, indicating that ozone pollution could undermine climate-change adaptation efforts through irrigation expansion. Applying an economic model, we examine the effects of a counterfactual, “pollution-free” scenario on yield losses, wheat prices, consumer and producer welfare, and government costs. We explore three policy scenarios in which the government support farmers at observed levels of either procurement prices (fixed-price), procurement quantities (fixed-procurement), or procurement expenditure (fixed-expenditure). In pollution-free conditions, the fixed-price scenario absorbs the fall in prices, thus increasing producer welfare by USD 2.7 billion, but total welfare decreases by USD 0.24 billion as government costs increase (USD 2.9 billion). In the fixed-procurement and fixed-expenditure scenarios, ozone mitigation allows wheat prices to fall by 38.19 to 42.96%. The producers lose by USD 5.10 to 6.01 billion, but the gains to consumers and governments (USD 8.7 to 10.2 billion) outweigh these losses. These findings show that the government and consumers primarily bear the costs of ozone pollution. For pollution mitigation to optimally benefit wheat production and maximize social welfare, new approaches to support producers other than fixed-price grain procurement may be required. We also emphasize the need to consider air pollution in programs to improve agricultural resilience to climate change

From reflection diaries to practical guidance for transdisciplinary research: learnings from a Kenyan air pollution project

Transdisciplinary research (TDR) approaches have been cited as essential for overcoming the intractable sustainability challenges that the world is currently facing, including air pollution, water management and climate change. However, such approaches can be difficult to undertake in practice and can consequently fail to add value. Therefore, examples of what works in practice (and what does not) are helpful to guide future research. In this study, we used a conceptual TDR framework as the basis to examine and evaluate the strengths and weaknesses of our approach in a project exploring air pollution in an informal settlement in Nairobi, Kenya. Reflection diaries exploring experiences of participation in the project were undertaken by the project team (comprising academic and community partners) at multiple time points throughout the project. These reflection diaries played an important role in evaluation and for providing space for team learning. Diaries were thematically coded according to the TDR framework to explore aspects of the project that worked well, and areas which presented challenges. We draw upon our reflections, and the extant literature, to make practical recommendations for researchers undertaking TDR projects in future. Recommendations focus on three key project stages (pre-funding, funded period, post-funding) and include; building the team in a way that includes all key stakeholders in relevant and appropriate roles, giving everyone sufficient time to work on the project, and ensuring regular and open communication. Building these recommendations into the design and delivery of transdisciplinary sustainability science projects will support progress towards achieving the Sustainable Development Goals (SDGs)

Using a co-created transdisciplinary approach to explore the complexity of air pollution in informal settlements

We present novel co-created transdisciplinary research that uses arts and humanities methods to explore air pollution in an informal settlement (Mukuru) in Nairobi, Kenya. Air pollution is a well-documented major human health issue, but despite many air pollution reduction interventions designed to improve health, these are frequently ineffective. Often this is because they fail to account for local knowledge, cultural practices and priorities of the intended recipients. Designing solutions therefore requires in-depth exploration of relevant issues with stakeholders. Researchers worked collaboratively with local residents to develop a range of methods to explore understandings of air pollution including interviews, storytelling, participatory mapping and theatre. Together, we uncovered contrasting definitions of air pollution, differing perceptions of who was responsible for enacting solutions, and overall a view that air pollution cannot be seen in isolation from the other issues faced by settlement residents. The methods used also allowed us to communicate about the topic with a wide audience. While we acknowledge that this research approach is more time consuming than traditional approaches, we urge other researchers wishing to address multifactorial problems, such as air pollution to use a mixture of qualitative, participatory and creative methods to engage with a wide range of stakeholders to elicit new and unexpected understandings that may not otherwise emerge

Transdisciplinary research as a means of protecting human health, ecosystems and climate by engaging people to act on air pollution

Air pollution harms the health of humans, nature and wildlife, agricultural crops and livestock and climate. As a result, it hinders the attainment of Sustainable Development Goals 3 (Good Health and Wellbeing), 7 (Affordable and Clean Energy), 11 (Sustainable Cities and Communities) and 13 (Climate Change). In order to improve human and (agro-)ecosystem health, One Health approaches for better air quality must account for local knowledge, cultural practices and priorities. People with lower socio-economic status often have limited awareness of air pollution yet are affected most through personal exposure and increased food prices. This case trialled a new, co-created transdisciplinary approach to air pollution awareness raising in the Mukuru community in Nairobi, Kenya. The pilot study used interviews, storytelling, participatory mapping, theatre, playful activities and music with the aim of discovering affected communities’ perceptions of air pollution, increasing understanding and empowering people to demand that policy makers develop and implement effective, inclusive air pollution abatement policies