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Background and Aims: Two main problems the globe currently facing are migration and weather variation. Weather change has a significant impact on the agricultural industry, which affects the majority of poor people. There is a dearth of adequate methodological documentation when examining the relationship between weather variation, agricultural output, and migration. We aimed to identify methodological reporting difficulties by reviewing the quantitative literature on weather‐related migration through agricultural channels. Methods: A systematic evaluation was conducted using papers published between January 2010 and June 2022, indexed in the SCOPUS, PUBMED, and Google Scholar databases. Using inclusion/exclusion criteria, we selected 22 original research articles out of 18,929 distinct articles for review, in accordance with the PRISMA guidelines. We extracted data from each study to understand how various concepts, research designs, and investigative techniques influence our understanding of migration patterns related to weather in the agricultural sector. Results: The majority (64%) of the study's data consisted of time series data. In 50% of the studies, secondary data were used. Additionally, 55% of these studies did not state the sample size. In 40% of the studies, model assumptions were fully adhered to, whereas in 36% of the studies, they were not followed at all. The majority of the articles used the Ordinary Least Squares technique, while about 41% applied the Two‐Stage Least Squares technique. Various tests were conducted across these studies, such as robustness checks (59.1%), endogeneity tests (31.8%), omitted variable bias tests (22.7%), sensitivity analyses (22.7%), and weak instrument tests (13.6%), to name a few. In the research we selected, the methodology section had various shortcomings and lacked organization. Furthermore, the justifications for deviations from model assumptions were unclear, potentially affecting the study outcomes. Conclusion: This study has important indications for researchers in studying climatic (weather) migration through agricultural channels besides for policymakers by giving a thorough review of the methods and techniques. Key points: Providing narrative insights on how various issues, research designs, and analytical techniques shape our understanding of the association between weather variation and migration via agricultural production.Providing a broad overview of the pertinent literature, covering 22 articles, as a complement to earlier studies.Our study has important ramifications for researchers studying climatic (weather) migration through agricultural channels as well as for policymakers by giving a thorough review of the methods and techniques currently used in this sector.Future studies on weather variation, agricultural production, and migration should use prudent and comparable models that capture whole climatic (weather) impacts on migration through mediating factors like agricultural production. [ABSTRACT FROM AUTHOR]

Agriculture is weather dependent, and changes in climate can have a drastic impact on our ability to feed, fuel, and clothe the world's population. Climate change is causing more frequent and unprecedented extreme weather events that are already negatively affecting agriculture. We need to assess the effects of extreme temperatures and rainfall on agriculture. Patterns of short‐term extreme weather events, such as elevated temperatures, flooding, and strong winds, are not predictable enough to design field experiments around. Process‐based crop and soil simulation models allow us to explore new management options and thus provide whole‐system‐based knowledge and management guides for different locations over variable climate conditions. By using crop simulation models, researchers can test different adaptation strategies and assess their effectiveness in reducing the impacts of climate change on agricultural production. In this paper, we discuss the development of crop models and how they have been used to assess the effects of a changing climate on agricultural productivity and propose methods for agriculture to adapt to those changes. We describe potential applications of crop models to assess regional issues such as irrigation demand, greenhouse gas emissions, and policy decisions. Better understanding of how weather and climate forecasts at various scales are provided and the reliability of these forecasts is important for using crop models as a planning tool. Different approaches for simulating long‐term climate change impacts on crop yield and seasonal yield forecasting are discussed. The use of ensemble models to better assess climate change impacts is also discussed. Core Ideas: Assessment of climate change impacts on agriculture requires a systems approach.Agriculture is weather dependent, and changes in climate can have a drastic impact on food production.Crop models can extend the results of physical experiments to better assess long‐term climate change effects on agriculture.Crop models are critical in assessing climate change impacts and developing adaptation and mitigation strategies. [ABSTRACT FROM AUTHOR]

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The main challenge facing agricultural crop production in the current global climate change scenario is sustainability. Drought, as a yield‐limiting factor, has become a major threat to international food security. Tolerance to drought is a complex trait and its response is carried out by various genes, transcription factors, microRNAs, hormones, proteins, cofactors, ions and metabolites. The complexity of the trait has limited the development of drought‐tolerant sweet potato cultivars by traditional breeding. Advances in sweet potato breeding to exploit the full potential of the crop to contribute to improved and higher performing sweet potato cultivars, adapted to increasingly risky rainfed conditions, mainly drought, are key to making food production systems more efficient and more tolerant to pressure from drought and other stressors. Genetic gain for yield potential in sweet potato has improved mostly in African countries, mainly as a result of an accelerated breeding scheme. The focus on maximising the utilisation of molecular tools for sweet potato improvement and yield has been recently explored in breeding programmes in sub‐Saharan Africa (SSA). This article provides an update on the trends and gaps in sweet potato breeding in SSA, reviewing the relevant strategies used to improve sweet potato in the region. Finally, the perspectives of using new advanced tools including genetic engineering and genome editing, and the challenges associated with climate change for further improvement of the crop are highlighted. Collaborative efforts in African countries are driving advances in breeding methods through the incorporation of molecular tools to develop drought‐tolerant sweet potato varieties that are important to global food security despite challenges posed by the drastic change in climate. [ABSTRACT FROM AUTHOR]

Northeast China (NEC) is the most prominent grain‐producing region in China. However, it is currently facing significant impacts from climate change. Since the climate‐related impacts on crop yield in this region are a major concern for society in the future, quantifying climate change impacts on crop yields in NEC is essential to ensure future food security. This study aimed to quantify the effects of future climate change on crop yields in NEC and explore adaptation strategies using the Crop Growth Model (PCSE) driven by downscaled CMIP6 climate projections under four Shared Socioeconomic Pathways (SSPs) scenarios during 2015–2100. Results showed that there could be average reductions in crop yields of 21.4% for maize and 4.2% for soybean by the year 2100 under SSP585 compared to the 2015 baseline. The increasing temperature was the dominant factor in reducing yields, although elevated CO2 and precipitation offered partial compensation. The optimized planting date brought noticeable benefits for rice and soybean but had limited effects on maize due to heat stress. Relocating rice expansion eastward and implementing earlier planting increased yields by up to 50% but adversely decreased soybean and maize due to competition. This study enriches our comprehension of climate change impacts on NEC agriculture, while also quantifying potential benefits and constraints of evaluated adaptations. The proposed adaptations may help mitigate projected yield declines in other key agricultural regions across the globe. Adjusting crop management practices to capitalize on changing climate factors shows promise as a strategy for sustaining production globally. Plain Language Summary: Northeast China (NEC) is essential for achieving food accessibility and food security in China, but its agricultural production is seriously threatened by climate change. This study investigated how climate change could impact maize, rice, and soybean crop yields in this region from 2015 to 2100, using the PCSE crop model and forcing from the international Coupled Model Intercomparison Project 6 (CMIP6) climate projections. Simulation results suggested rising temperatures would negatively affect crop yields, especially for maize. Increased carbon dioxide and rainfall partially offset these losses. By 2100, average declines were projected for maize (−21%) and soybeans (−4%), respectively. Altering planting dates to match crop needs was an effective adaptation to boost yields, with rice benefiting the most. Relocating rice production eastward and expanding its area substantially increased simulated rice yields (+62%) but decreased other crops due to competition (−32% maize, −28% soybeans). Even with adaptations, some areas still showed yield declines, indicating extra measures may be needed to maintain production. Overall, this study suggests significant risks to crop yields from climate change in Northeast China, with adaptations like optimized planting and strategic crop relocation able to mitigate some but not all of the projected impacts. Key Points: Rising temperatures negatively impacted simulated future crop yields, especially for maizeAdjusting planting dates boosted yields for rice and soybeans but had limited benefits for maizeRelocating and expanding the rice area increased yields substantially [ABSTRACT FROM AUTHOR]

Climate change is a constant threat to global food security. In Sub‐Saharan Africa (SSA), extended dry spells, heavy rainfall, flooding, and tropical storms have driven a large percentage of the population to a severe food crisis. Climate‐smart agriculture (CSA) is a potential comprehensive solution whose adoption can mitigate climate change and its ramifications on the state of food security in the region. CSA combines innovation, the use of technology, extensive research, stakeholder involvement, and data to increase food production, optimize resource allocation and utilization, and enhance the region's ability to feed its population. The adoption of CSA has succeeded in increasing agricultural productivity in several parts of SSA and will help towards the building of resilience food systems across the region amid constant and unpredictable climate change and its far‐reaching impacts in the region. For the sustained and universal adoption of CSA within the region, there is a need for more stakeholder involvement in its development and adaptation to the needs of specific communities. Furthermore, it is necessary to leverage the positive impact of the approach by expanding its scope beyond climate change mitigation to prevention and control, and ultimately help in achieving the United Nations SDG 2 and 13. [ABSTRACT FROM AUTHOR]

Agriculture is directly related to food security as it determines the global food supply. Research in agriculture to predict crop productivity and losses helps avoid high food demand with little supply and price spikes. Here, we review ten crop models and one intercomparison project used for simulating crop growth and productivity under various impacts from soil–crop–atmosphere interactions. The review outlines food security and production assessments using numerical models for maize, wheat, and rice production. A summary of reviewed studies shows the following: (1) model ensembles provide smaller modeling errors compared to single models, (2) single models show better results when coupled with other types of models, (3) the ten reviewed crop models had improvements over the years and can accurately predict crop growth and yield for most of the locations, management conditions, and genotypes tested, (4) APSIM and DSSAT are fast and reliable in assessing broader output variables, (5) AquaCrop is indicated to investigate water footprint, quality and use efficiency in rainfed and irrigated systems, (6) all models assess nitrogen dynamics and use efficiency efficiently, excluding AquaCrop and WOFOST, (7) JULES specifies in evaluating food security vulnerability, (8) ORYZA is the main crop model used to evaluate paddy rice production, (9) grain filling is usually assessed with APSIM, DAISY, and DSSAT, and (10) the ten crop models can be used as tools to evaluate food production, availability, and security. [ABSTRACT FROM AUTHOR]

Environmental stresses including salinity, drought, cold, warmer temperatures, alterations in precipitation patterns, fluctuations of weather events, and increasing insect and disease infestations negatively affect crop production and nutritional values. This situation becomes further complicated due to the changing climatic conditions, thus raising concern about food security worldwide. Some worst‐case projections indicated that by 2100, CO2 concentrations will reach 950 parts per million, temperatures will climb by 3.5 to more than 8°C, sea level will rise by more than 2.4 meters, and the average farmland drought risk index will increase from 52.45 to 129. In addition, average precipitation will increase by 1%–3% in some areas and atmospheric water vapor will increase by 6%–7% for every degree of temperature rise. Rice (Oryza sativa L.) is a staple crop in many parts of the world. The main objective of this review is to highlight the prospects of rice for future climatic conditions. The present review depicts the advantages and prospects of rice and addresses why rice is a better option as a cereal crop for the future situations for food and nutritional sustainability. The impact of climate change on food and nutritional security can be mitigated by developing biotic and abiotic stress‐tolerant and biofortified rice varieties. These rice cultivars can withstand the negative effects of climate change while also meeting the nutritional needs of future generations. Furthermore, this review underlines the forthcoming issues and measures that should be addressed to assure a sustainable food and nutritional supply in the era of global climate change. [ABSTRACT FROM AUTHOR]

The world needs more than double its current agricultural productivity by 2050 to produce enough food and feed, as well as to provide feedstock for the bioeconomy. These future increases will not only need to be sustainable but without comprommising the nutritional quality, and ideally also need to decrease greenhouse gas emissions and increase carbon sequestration to help mitigate the consequences of global climate change. These challenges could be tackled by developing and integrating new future‐proof crops into our food system. The H2020 CropBooster‐P project sets out plant‐centered breeding approaches guided by a broad socio‐economic and societal support. First, the potential approaches for breeding crops with sustainably increased yields adapted to the future climate of Europe are identified. These crop‐breeding options are subsequently prioritized and their adoption considered by experts across the agri‐food system and the wider public, taking into account environmental, economic and other technical criteria. In this way, a specific research agenda to future‐proof our crops was developed, supported by an eventual implementation plan. [ABSTRACT FROM AUTHOR]

The European Commission plans to reduce pesticides and fertilizer use in agriculture substantially under its Green Deal's Farm to Fork strategy. Policy alternatives are needed to overcome these input reductions, for instance by allocating R&D towards commodities most affected by climage change and improving the precision of input use. Since climate change is likely to impact agriculture negatively, productivity measures that account for all inputs and climate change impacts can help to weigh such policy responses. We adopt U.S. farm‐level data and a multi‐output and multi‐input production technology to estimate relative farm productivity performances with climatic effects. Exploiting long‐term weather patterns, we find comparative advantages among some crop farms and ample productivity improvement potential across all of them. [ABSTRACT FROM AUTHOR]

The response of bees to changing environmental temperatures has implications for pollination in natural and agricultural systems, with rising average temperatures and increased environmental stochasticity predicted to cause pollinator population declines. A growing body of evidence for the role of native bees in crop pollination suggests that understanding the temperatures at which bees are active is important for maintaining agricultural productivity under climate change. This study used two methods to sample bees at strawberry farms in south‐eastern Australia, matching activity observations with microclimate temperature to understand how temperature impacts bee activity. Apart from Apis mellifera (introduced), two native bees were identified, Lasioglossum spp. and Exoneura robusta. Apis mellifera was the most abundant species across all environmental temperatures, and E. robusta the least. Visual and sweep‐netting survey results found activity temperature range was broader for A. mellifera (16.21–41.05°C) than Lasioglossum (16.49–38.91°C) and E. robusta (26–38.82°C). The results suggest that activity temperature varies among bee species, with potential implications for community composition and plant pollination under climate change. [ABSTRACT FROM AUTHOR]

BACKGROUND The agricultural production system is facing increasing demand pressure and environmental pressure. Green and efficient production methods are urgently needed in order to further enhance the yield of winter wheat and reduce the negative impact on the environment. Here, we analyzed the potential yield and yield gap of winter wheat in Shandong Province of China from 1981 to 2009. Meanwhile, we specified the effects of sowing time, irrigation and fertilization scheme, and variety characteristics on winter wheat. RESULTS: In the past 29 years, the yield gap in most areas of Shandong has become smaller, because the actual yield has increased and the potential yield has changed little under the background of climate change. In addition, it is found that delaying sowing date is beneficial to increase yield by helping winter wheat avoid adverse climate conditions. Also, an irrigation amount of 240 mm and nitrogen application amount of 180–210 kg ha−1 are best to maintain high yield, high resource utilization rate and low environmental pollution in this area. These suggested levels are lower than those currently used by many local farmers. Wheat varieties with longer grain‐filling period and photoperiod response, higher grain‐filling rate and grain weight were more adaptable to climate change. CONCLUSION: Improving agronomic management measures can significantly increase the yield of winter wheat and narrow the yield gap. This study can provide valuable information for improving the production potential of winter wheat, and for reducing the damage of agricultural activities to the environment. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Today's climate‐turbulent world is rife with food insecurity—threatening economic development trajectories by stunting growth, subsequently reducing employability and labor productivity, especially for developing countries. The pandemic has exacerbated these adverse effects and reveals the critical need to put in place policies that can safeguard and sustain trade flows in agricultural products. For the vast majority of countries, food security cannot be guaranteed by domestic production alone. If certain crops are domestically untenable or yields are temporarily poor, imports are essential. Additionally, exports of agricultural products provide a major source of income for some of the poorest people around the world. This article explores the interplay between climate change, the production and the trade of agricultural products, and the resulting food security implications. It then examines the existing trade policies governing agricultural trade and provides recommendations for action at the global, regional, and country levels. [ABSTRACT FROM AUTHOR]

Summary: Climate change is increasing global temperatures and the frequency and severity of droughts in many regions. These anthropogenic stresses pose a significant threat to plant performance and crop production. The plant‐associated microbiome modulates the impacts of biotic and abiotic stresses on plant fitness. However, climate change‐induced alteration in composition and activities of plant microbiomes can affect host functions. Here, we highlight recent advancements in our understanding of the impact of climate change (warming and drought) on plant–microbiome interactions and on their ecological functions from genome to ecosystem scales. We identify knowledge gaps, propose new concepts and make recommendations for future research directions. It is proposed that in the short term (years to decades), the adaptation of plants to climate change is mainly driven by the plant microbiome, whereas in the long term (century to millennia), the adaptation of plants will be driven equally by eco‐evolutionary interactions between the plant microbiome and its host. A better understanding of the response of the plant and its microbiome interactions to climate change and the ways in which microbiomes can mitigate the negative impacts will better inform predictions of climate change impacts on primary productivity and aid in developing management and policy tools to improve the resilience of plant systems. [ABSTRACT FROM AUTHOR]

Aims: Terrestrial biodiversity is threatened by land use change. Modelling suggests that the remaining, potentially arable areas of natural intact vegetation (rNIV) of 9 of 35 global biodiversity hotspots may be converted to agriculture by 2050, committing their endemic species to extinction. Studies have shown that if the global population adopted a healthy, mostly plant based diet, agricultural area expansion can be reduced. We want to examine to what degree this applies to the regions covered by biodiversity hotspots. Location: Global. Time period: 2020–2050. Major taxa studied: No particular taxa. Methods: For every biodiversity hotspot, we simulate climate change impacts on agricultural productivity, and estimate food demand shifts from 2010 to 2050 by processing population and income growth projections. We quantify the net change in rNIV by 2050 in all hotspots by calculating the agricultural area necessary to meet the food demand under a business as usual, a healthy diet, a healthy diet plus agricultural intensification, and a healthy diet plus agricultural intensification plus crop change scenario. Results: In the healthy diet scenario, the rNIV of 16–21 hotspots can be preserved entirely, but 5–6 hotspots in less developed regions may lose all rNIV to agricultural area expansion. In these regions, a healthy diet implies an increase in consumed calories and no change in the already high share of plant‐based calories. When combined with agricultural intensification, these hotspots will still lose 7%–92% of rNIV. Only an additional change in crop mix patterns may preserve all. Main conclusions: While a change in dietary habits may be sufficient for preservation of rNIV in many hotspot regions, a healthy diet actually puts more pressure on rNIV in other hotspot regions. Intensifying agriculture and optimizing crop selection should be priorities in those regions to mitigate the expected loss of rNIV to agricultural expansion. [ABSTRACT FROM AUTHOR]

Water has always been a driver of human mobility, migration, and displacement. But water is increasingly central to explaining environmental migration in the context of climate change. Most studies of the relationship between water and environmental migration are framed around punctuated, extreme weather events and disasters that either limit agricultural or livestock productivity or make a community physically unlivable. The chronic experiences of household water insecurity and poor water governance also shape migration decision‐making through a variety of social, political, and economic factors, but these relationships have received considerably less attention. This article provides an overview of punctuated and chronic water‐related triggers of environmental migration at the household level. We also offer a conceptual framework based on multiphasic response theory that highlights water's multiple roles in migration decision‐making. We close by reflecting on key gaps in the climate‐water‐migration literature, identifying research questions that might help us better understand these relationships, and considering the implications for sustainable development policies that could potentially ease pressures on water‐related displacement. [ABSTRACT FROM AUTHOR]

Agriculture accounts for 70% of the global use of available freshwater. Projections show that demand for water will increase significantly due to climate change, population growth and development of agricultural enterprises globally. There is a need to develop water‐use efficient crop cultivars for sustainable agricultural production. Sorghum [Sorghum bicolor (L.) Moench.] is a powerhouse crop in drier regions supporting more than 500 million people. It is a relatively drought‐tolerant crop adapted to grow and yield in marginal environments where other dominant crops such as maize and wheat fail to survive. However, the mean yield of sorghum in the semi‐arid regions has stagnated around 1.0 ton/ha compared with the global average of 2.5 ton/ha, mainly due to recurrent droughts and heat stress. Breeding for drought‐tolerant cultivars is an economic and sustainable mitigation strategy against the current and projected drought stress. Therefore, the objectives of this review were to document the impact of drought stress and the key mitigation strategies under drought‐prone semi‐arid sorghum production systems. The first section of the review highlighted the impact of drought and its mitigation strategies emphasizing on the use of drought‐tolerant cultivars as the best strategy. This is followed by perspectives on aspects of drought‐response mechanisms, breeding methods and complementary technologies for drought tolerance. Integration of the conventional and molecular breeding technologies with rapid generation advancement methods could reduce the breeding cycle and increase the efficiency of deploying new varieties. Information presented in this review will guide agronomists and breeders to develop and deploy drought‐tolerant sorghum cultivars that are adapted to the changing production environments in the semi‐arid regions. [ABSTRACT FROM AUTHOR]

BACKGROUND A decrease in rainfall is one of the main constraints on wheat production, although the association of wheat with arbuscular mycorrhizal fungi (AMF) may be an alternative for crop production under drought conditions. In the present study, we used three wheat cultivars (Purple, Ilustre and Maxi Baer) inoculated with two AMF strains, one obtained from the hyperarid Atacama Desert (northern Chile; Fm) and the other obtained from southern Chile (Cc). Plants were maintained under two irrigation conditions (normal irrigation and drought) and the physiological behaviour and enzymatic and nonenzymatic antioxidant activities in the shoots were determined. In addition, the phenolic compounds were identified by high‐performance liquid chromatography‐dioide array detection‐electrospray ionization‐tandem mass spectrometry and quantified. RESULTS: AMF colonization produced higher levels of efficiency of photosystem II and photosynthetic pigments. High values of catalase in Purple‐Cc, ascorbate peroxidase in Purple‐Cc, glutathione reductase in Maxi‐Cc and superoxide dismutase in Purple‐Cc, all under stress, were registered. Of the inoculated cultivars, Purple‐Cc showed the highest flavonoid levels, whereas hydroxycinnamic acids were higher in Maxi‐Fm without drought, with apigenin and luteolin being the most abundant. High levels of phenols were present in the Ilustre‐Fm plants without drought. Under normal irrigation, high levels of antioxidant activity were registered in the AMF treatments, whereas, under stress conditions, in general, high values were observed under the Fm inoculation. CONCLUSION: Our results showed that the greatest antioxidant activity and phenolic content occurred in wheat plants inoculated with AMF, indicating their influence on coping with water stress, which is of importance in vast areas where global climate change is resulting in diminished rainfall. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

With the objective of trying to understand the adaptability of agriculture across the Canadian Prairies under climate change, simple‐to‐use agroclimatic indices were calculated for the base climate period of 1981 to 2010 and for both the medium (RCP4.5) and high (RCP8.5) emission projections extending to the distant future (2071–2100). The agroclimatic indices included the Effective Growing Degree Days (EGDDs), Growing Season Length (GSL), the Climate Moisture Index (CMI), and the Temperature Humidity Index (THI). For climate change in 30‐year periods, these indices were calculated as multi‐model ensembles of six Global Climate Models recommended under the Coupled Model Intercomparison Project Phase 5 (CMIP5) for the study area. We found that the GSL, EGDDs, CMI, and THI were amplified above the values of the base climate period in the order of 40–50 days, 600–1200 heat units, −100 to −120 mm and 3–4 THI units by the close of the distant future (2071–2100) under the RCP4.5 and RCP8.5, respectively. This amplification has implications on where crop and livestock production could become more suitable or riskier in future. Opportunities include expanding crop and livestock production to more northerly regions which currently have insufficient heat units, a short growing season and unfavourable temperature humidity thresholds for livestock production. Moisture deficits will continue to be the greatest risk during the growing season under climate change scenarios but options exist to implement adaptive measures such as staggering seeding times to take advantage of moisture availability in the spring and autumn seasons and crop substitution. This study has relevance for policy and program formulation and implementation in Canada's agricultural regions and potentially, other areas of the world with similar climate change outcomes. [ABSTRACT FROM AUTHOR]

Understanding concurrent drought events in global main croplands is crucially important for food security, effective adaptation to climate change and human well‐being. Yet, there is a lack of comprehensive studies on concurrent drought probability changes among main crop production countries on a global scale, especially for the future. Here, we studied concurrent drought among 26 main crop production countries for the time period 1861–2099. During the historical period, probability of concurrent moderate and severe drought among the countries was relatively low, and the maximum concurrent moderate and severe drought probability will double and triple under RCP8.5 extreme climate, respectively. Concurrent probability of moderate and severe drought between China and United States of America, Brazil and Russia will be at least 6% and 5% under RCP8.5, respectively, compared with zero in the historical period. Limiting RCPs to RCP2.6 can decrease the concurrent probability of severe drought at least 2% (at least 3% for RCP8.5). Plain Language Summary: In the past over 100 years, the world had rarely experienced extreme drought events that occurred at the same time among major food producing countries. Yet, there is a lack of comprehensive studies on the changes of the concurrent drought probability among global main crop production countries, especially for the future. We studied the concurrent drought among 26 global main crop production countries for the time period 1861–2099. We find that the maximum concurrent probability of moderate and severe drought will double and triple, respectively, under the business as usual climate scenario. Concurrent probability of moderate and severe drought between China and United States of America, Brazil and Russia will be at least 6% and 5% under future business as usual climate, compared with zero in the historical period. Key Points: Maximum concurrent probability of moderate and severe drought will double and triple under RCP8.5, respectivelyConcurrent probability of moderate and severe drought between China and United States of America, Brazil and Russia will be at least 6% and 5% under RCP8.5Limiting RCPs to RCP2.6 can decrease the concurrent probability of severe drought at least 2% (at least 3% for RCP8.5) [ABSTRACT FROM AUTHOR]

Climate projections indicate that temperatures in Latin America and the Caribbean (LAC) will rise by between 1.6 °C and 4 °C by the end of the century while changes in precipitation levels are expected to vary significantly across the region. This article estimates the impact of climate change on total factor productivity (TFP) and production. It combines data from the University of East Anglia's Climatic Research Unit (CRU), the Intergovernmental Panel on Climate Change (IPCC), and the Food and Agriculture Organization (FAO) on 28 LAC countries for a 54‐year period (1961–2014) in order to inform policy makers of the cost of output losses in the absence of viable climate adaptation strategies. We use estimates of a random‐parameter stochastic production frontier (SPF) model specification to capture heterogeneity in technology and partial output elasticities across countries and unobserved environmental characteristics. Results show that change in output is mainly driven by an average annual TFP growth rate of.95%. Climate change induces significant reductions (9.03–12.7%) in productivity over the 2015–2050 period. In terms of output, these losses range from USD $14.7 to $31.4 billion dollars in the LAC region, depending on the scenario and the discount rate used. [ABSTRACT FROM AUTHOR]

Water‐limited environments account for half of the earth's land surface, and dryland agriculture acreage is projected to expand due to climate changes. Examining typical dryland yield potentials and yield improvement measures is crucial for developing future dryland crop production systems. This case study used crop modeling to analyze dryland maize yield potential (YPd), farmers' yield potential (YPf), and actual farm yields (Ya) from 1990 to 2015 in three counties in western Kansas (i.e., Thomas, Greeley, and Finney in the U.S. Great Plains region). The calibrated APSIM‐Maize model along with actual yields was used to estimate yield gaps attributed to: (a) agronomic factors (YG1 = YPd − YPf) and (b) socioeconomic constraints (YG2 = YPf − Ya). Observed climate conditions during maize‐growing seasons showed warming, brightening, and drying trends for all three counties in western Kansas from 1990 to 2015. Our results showed that the current actual farm yields (Ya) in western Kansas represented only 34%, 32%, and 28% of YPd in Thomas, Greeley, and Finney counties, respectively, indicating significant exploitable yield gaps. Agronomic factors (YG1) contributed the greatest to the yield gap in Greeley and Finney counties, whereas socioeconomic constraints (YG2) offered the greatest opportunity for improvement in Thomas county. Our analysis suggested that improving agronomic management could be a greater priority for further yield improvement in Greeley county, but selecting an appropriate hybrid was a greater priority in Finney county. [ABSTRACT FROM AUTHOR]

In this article, we use spatially granular climate data merged with four waves of household survey data in Uganda to examine empirically the relationships among high temperatures, total value of crop production, and the adoption and adoption duration of two sustainable agricultural practices (organic fertilizer adoption and maize–legume intercropping). We do this using a fixed‐effect model with instrumental variables to address potential endogeneity issues. Our findings indicate that the adoption of these practices has a positive effect on the total value of crop production, and such effect increases monotonically as temperatures increase from long‐term averages. Moreover, the number of years a farmer uses the practice is associated with higher total value of crop production, and this relationship holds across the full distribution of high temperature deviations. Taken together, the results suggest that promoting the adoption, and particularly the sustained adoption, of these practices can help to address the risks posed by rising temperatures to Ugandan agriculture and the livelihoods of farmers who depend on it. [ABSTRACT FROM AUTHOR]

Climate‐smart practices that have added benefits of improving agricultural productivity are an imperative for improving smallholder farming. However, there are few insights into how smallholder climate‐smart adaptation practices influence their technical (in)efficiency. Thus, the objective of this study was to evaluate the impact of smallholders' climate‐smart adaptation practices on their crop production technical efficiency (TE) in the Lemo district of southern Ethiopia. We used focus group discussion, experts' consultations and household survey to collect data from 600 smallholder crop producers across six rural kebeles. We computed smallholder farmers' climate change adaptation indices based on experts' consultations and estimated the TE of the smallholder farmers using Stochastic Frontier Analysis. The smallholder farmers in the Lemo district have adopted climate‐smart agricultural practices such as terracing, crop diversification, improved soil amendment practices, varying planting or harvesting schedules, and crop rotation. The smallholder farm households practicing more adaptation strategies on a larger scale were more technically efficient than their counterparts with their TE averaging 11.31, 8.62, and 6.71% for major crops, wheat (Triticum aestivum L.), and teff [Eragrostis tef) (Zucc.) Trotter] production, respectively. Our model also revealed that adaptation to climate change has a positive and significant contribution to the technical efficiency of major crops, wheat, and teff production. Other key determinants of TE are farming experience, education, access to extension services, livestock holdings, and farm household income. Overall, our study suggests a policy shift to promote smallholder farmers adaptation to climate change using climate‐smart practices for an effective response to climate change impact while enhancing TE. Core Ideas: An activity‐based adaptation index for climate change was measured.There was positive correlation between climate change adaptation practices and crop production efficiency.Smallholder climate‐smart adaptation practices have significant effect on technical efficiency.Farmers using climate‐smart practices at a larger scale are more technically efficient. [ABSTRACT FROM AUTHOR]

Climate change will lead to more frequent and severe drought periods which massively reduce crop production worldwide. Besides drought, nitrogen (N)‐deficiency is another critical threat to crop yield production. Drought and N‐deficiency both decrease photosynthesis and induce similar adaptive strategies such as longer roots, reduction of biomass, induction of reactive oxygen species (ROS), and antioxidative enzymes. Due to the overlapping response to N‐deficiency and drought, understanding the physiological and molecular mechanisms involved in cross‐stresses tolerance is crucial for breeding strategies and achieving multiple stress resistance and eventually more sustainable agriculture. The objective of this study was to investigate the effect of a mild N‐deficiency on drought stress tolerance of tomato plants (Solanum lycopersicum L., cv. Moneymaker). Various morphological and physiological parameters such as dry biomass, root length, water potential, SPAD values, stomatal conductance, and compatible solutes accumulation (proline and sugar) were analyzed. Moreover, the expression of ROS scavenging marker genes, cytosolic ASCORBATE PEROXIDASES (cAPX1, cAPX2, and cAPX3), were investigated. Our results showed that a former mild N‐deficiency (2 mM NO3−) enhances plant adaptive response to drought stress (4 days) when compared to the plants treated with adequate N (5 mM NO3−). The improved adaptive response was reflected in higher aboveground biomass, longer root, increased specific leaf weight, enhanced stomatal conductance (without reducing water content), and higher leaf sugar content. Moreover, the APX1 gene showed a higher expression level compared to control under N‐deficiency and in combination with drought in the leaf, after a one‐week recovery period. Our finding highlights a potentially positive link between a former mild N‐deficiency and subsequent drought stress response in tomato. Combining the morphological and physiological response with underlying gene regulatory networks under consecutive stress, provide a powerful tool for improving multiple stress resistance in tomato which can be further transferred to other economically important crops. [ABSTRACT FROM AUTHOR]

Climate change affects global agricultural production and threatens food security. Faster phenological development of crops due to climate warming is one of the main drivers for potential future yield reductions. To counter the effect of faster maturity, adapted varieties would require more heat units to regain the previous growing period length. In this study, we investigate the effects of variety adaptation on global caloric production under four different future climate change scenarios for maize, rice, soybean, and wheat. Thereby, we empirically identify areas that could require new varieties and areas where variety adaptation could be achieved by shifting existing varieties into new regions. The study uses an ensemble of seven global gridded crop models and five CMIP6 climate models. We found that 39% (SSP5‐8.5) of global cropland could require new crop varieties to avoid yield loss from climate change by the end of the century. At low levels of warming (SSP1‐2.6), 85% of currently cultivated land can draw from existing varieties to shift within an agro‐ecological zone for adaptation. The assumptions on available varieties for adaptation have major impacts on the effectiveness of variety adaptation, which could more than half in SSP5‐8.5. The results highlight that region‐specific breeding efforts are required to allow for a successful adaptation to climate change. [ABSTRACT FROM AUTHOR]

The arid and semi‐arid regions are highly vulnerable to climate change and variability. Agricultural production in these regions is particularly vulnerable because of its heavy dependence on climate conditions. Therefore, it is important to improve the projections of future agro‐climatic conditions. This study investigates the changes in agroclimatic conditions for growing Chinese Medicinal Yam (CMY) in the semi‐arid North China during 2031–2050 under the Representative Concentration Pathway (RCP) 4.5 and 8.5 emission scenarios. It employs high‐resolution climate data provided by the regional climate model (RCM) of Providing Regional Climates for Impacts Studies (PRECIS‐2.0). The changes in CMY yield and producing area under future climate change are simulated by the Agro‐Ecological Zone model. The simulations are based on newly calibrated cultivar parameters. The results show that the high‐resolution RCM simulation corresponds better with the observations of precipitation and temperature than the general circulation model (GCM). Because of the increased temperature and precipitation, the agroclimatic conditions for CMY are going to improve. While the traditional yam production area will maintain suitable for CMY production, the CMY production areas will further expand northward in the future. The average yield will increase by 1,196 and 1,336 kg DM/ha under RCP 4.5 and 8.5 emission scenarios, respectively. Key Points: Improving the projections of future agro‐climatic conditions in the semi‐arid North ChinaThe high‐resolution Providing Regional Climates for Impacts Studies projections correspond better with the observationsThe Chinese Medicinal Yam production areas will expand northward in the future, the average yield will increase by 1196–1336 kg DM/ha in the future [ABSTRACT FROM AUTHOR]