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Changes in climatic conditions increase risks associated with crop production in certain regions. Early detection of these changes enables the implementation of suitable adaptation measures in the local area, thereby stabilising agricultural production. Our analysis shows a significant shift in climatic conditions in Czechia between 1961 and 2020. We examined the changes in observed temperature conditions, precipitation distribution, drought occurrences, and frost incidents at a high resolution (0.5 × 0.5 km). The outputs show a significant increase in air temperatures and drought occurrence. Temperature totals above 5 °C in 1991–2020 were 15% higher than in 1961–1990. Furthermore, the relative change in totals above 10 °C was 26% after 1991. Over the last 30 years, drought incidence was four times more frequent than in 1961–1990, particularly in spring. In contrast, no significant changes in the distribution of precipitation occurred, and there was a slight decrease in the probability of frost during the growing season. Ongoing climate change brings warmer and drier conditions to higher-altitude regions in Czechia. Assessing climatic conditions on a global scale is less precise for relatively small and topographically diverse countries like Czechia due to coarse resolution. Therefore, a high-resolution analysis is more appropriate for these countries. [ABSTRACT FROM AUTHOR]

In order to stress test loan portfolios for the impacts of climate change, historical events need to be analyzed to create templates to stress test for future events. Using the 2012 Midwestern US drought as an example, this work creates a stress-testing template for future droughts. The analysis connects weather and crop yield data to impacts on local macroeconomic conditions by comparing drought-impacted agricultural counties with nearby urban counties. After measuring the net macroeconomic impacts of the drought, this was used as an overlay with existing macroeconomic stress models to stress test a lender in a different part of the US for possible drought impacts. Having a library of such climate events would allow lenders to stress test their portfolios for a wide range of possible impacts. [ABSTRACT FROM AUTHOR]

Abstract: Crop models often simulate drought impacts with full and no irrigation scenarios, while planners are more interested in whether the current available irrigation water can cope with the future more serious droughts. This paper addresses a key constraint common to modeling studies: the limited representation of actual irrigation water supply. We present a data-driven approach to identify a benchmark for agronomic drought risk levels as defined by water availability thresholds at the baseline climate (1980–2008) using reported crop yields, climate and irrigation statistics. Then, holding the current irrigation supplies, we adopted Bayesian formula to estimate magnitude of the future water availability and the associated probability of crops yields being decreased to rainfall-deficiency under climate conditions in 2030s (2020–2040) based on the RegCM3 climate model output driven by IPCC SRES A1B scenario. Results reveal that future drought stress would overwhelm the irrigation capacity of current supplies in northern and western China, while drought remains at baseline climate levels in the central, eastern and southern regions. The largest increases in the probability of projected drought risk were in northeast and southwest, ranging from 14% to 28% above baseline climate. Regional drought impacts for grain self sufficiency are discussed. [Copyright &y& Elsevier]

Abstract: There are clear indications that in the future the Alpine region will increasingly suffer from droughts. In this paper, a simple method is devised for determining probability of drought occurrence and exceedance of severity thresholds. A reconstruction of drought occurrence during the past 100 yr indicates that the method is able to detect major events and also to correctly gauge their relative severity. The procedure is used in conjunction with climate simulations for the European region valid for 2071–2100 to study the impact of climate change on the likelihood and severity of droughts. The climate scenario used for the analysis refers to a SRES A2 emission pathway and specifies in particular a decrease in the frequency of wet days of about 20% with respect to the growing season of summer crops (April to September). Under these conditions the frequency of droughts is shown to increase from about 15% to more than 50%. In addition, the results indicate an overall shift in the distribution toward higher severity scores. The average severity increases by a factor of two, but also at the upper end of the spectrum severity increases by more than 20%. It is argued that this will affect the perception of extreme droughts, i.e. of those events rarer than the 10th percentile of the distribution. If this scenario comes true, by the end of the 21st century droughts comparable in severity to the 2003 event would represent the norm rather than the exception. [Copyright &y& Elsevier]

Gansu Province is a high-incidence area for many meteorological disasters. In this research, using affected and covered risk indices for the main agro-meteorological disasters (drought, flood, wind hail, and frost), the variability characteristics of agro-meteorological disasters were analyzed and the risks calculated based on the information diffusion method against the background of climate change in Gansu Province. The results showed that of affected (crop yield reduced by >10%) and covered (crop yield reduced by >30%) areas for drought and frost tended to increase between 1978 and 2014, whereas those for flood and wind hail tended to decrease. The affected and covered risk indices for drought increased, those for flood and wind hail showed a slight decreasing trend, the frost affected risk index decreased, and the frost covered risk index increased. Comparing the four kinds of risk for agro-meteorological disasters, the estimated risk decreased as the affected and covered risk indices increased. The risk of drought was more serious than those for other agro-meteorological disasters for the same affected risk index, followed by frost, flood, and wind hail. The most serious disaster agro-meteorological covered risk was wind hail, followed by drought, flood, and frost. After a rapid change in temperature in 1994, the estimated affected risk values of drought and frost increased on average by 17.56 and 96.83%, respectively, whereas the estimated risks of flood and wind hail decreased on average by 15.59 and 5.90%, respectively. After the temperature jump, the estimated covered risk of drought increased on average by 19.57%, whereas those of flood, wind hail, and frost decreased on average by 3.02, 1.78, and 26.10%, respectively. These new scientific discoveries are significant for agro-meteorological disaster prevention in Gansu Province. [ABSTRACT FROM AUTHOR]

Agro-meteorological (AM) disasters have been reported to be more frequent with climate change. In this study, the spatial and temporal changes in the frequency of major AM disasters affecting maize production are investigated by analyzing observed records at 224 national AM stations in China from 1991 to 2009. To investigate the temporal changes of the disasters with climate warming, the whole study period was separated into a cool period (1991-2000) and a warmer one (2000-2009). We found drought was the most common disaster with a frequency of 49 %, followed by chilling injures (19.46 %). The frequency of disasters affecting maize increased significantly during the reproductive growth period than the vegetative growth period. Spatial patterns of major disaster frequency were characterized by region-specific, with more cold stress in northeastern China, drought in northern and western China, and rainstorms in southwestern China. Our study highlighted that the frequency and scope both increased significantly, implying a potential increasing risk for maize production. It is critical and important for local farmers and governors to take reasonable and timely adaptation measures based on the latest disasters' features to mitigate the potential yield loss from AM disasters in order to ensure food security in China. [ABSTRACT FROM AUTHOR]