The Effects of Extreme Weather Disasters in the European Food Availability

Over the last 20 years, it was reported an increase in worldwide extreme weather disasters (EWD), such as droughts (+29%), floods (+134%), and extreme temperature (+232%) like heatwaves. While the mortality rate of these events decreased, EWD are associated with a significant increase in economic damage and in the number of people affected (> 3 billion). The EWD can significantly impact agriculture by exacerbating fluctuations in crop yields and, consequently, in food availability and food prices. Thus, by means of the interconnections of the world food system, EWD have potential to threaten local to global food security. The challenges for agriculture are not only linked to changes in the long-term average climate, but particularly to EWD, which are usually more impactful and generally more uncertain. However, in the occasion of EWD occurrence, national and international disaster loss databases typically report populations affected and damage to human infrastructure, but rarely report damage or losses in the agriculture sector. As a result, agricultural impacts associated with these events are not well quantified across larger spatial scales. In particular, it remains insufficiently understood what are the trends in crop losses, and what are the implications that EWD may represent to food trade. The European Union (EU) was chosen as a case study, as it is one of the largest global exporter and importer of agri-food products, with its food system deeply linked with other regions. Here, disaster records were used as a metric for extreme weather event impact analysis. Records of droughts, heatwaves, floods, and cold waves (EM-DAT) were combined with observational agricultural data (FAOSTAT) to evaluate disasters crop responses in Europe and in its Non-EU food suppliers. A superposed epoch analysis (SEA) a time series statistical method used in data analysis was used to estimate the impact of EWD on the average production, yield, and harvested area of selected crops. The larger implications of disaster impacts in Non-EU food suppliers to the EU food imports, were explored based on the import share per supplier (EUROSTAT). At the EU level, in addition to the SEA to estimate crop impacts, the trend of production anomalies was evaluated over time, per disaster type and per bioclimatic region. The research carried out allows to assess the effects of EWD in the EU food availability, while expanding the analysis to different crops and geographical regions. In particular, the exposure of the EU food import dependency to EWD was evaluated, and also the degree of loss in the EU crop production resulting from the occurrence of such events. Despite a diversified external market, the EWD impacts on crops grown in Non-EU suppliers represent a substantial and negative exposure to EU food imports. Production losses of soybeans, tropical fruits, and cocoa associated to droughts and heatwaves but also floods, lead to an overall decline, up to 16%, in the EU import-weighted share of each crop. At the EU level, the severity of aggregated heatwave and drought impacts on crop production roughly tripled over the last 50 years. In particular, in every new year with a drought, the EU cereal production losses increase by 3%. The frequency of droughts, heatwaves, floods, and cold waves significantly increased over time. Major losses are found for cereals, but also vegetables and oil crops in the Eastern countries, while smaller losses are estimated in Southern but also Central European countries. Even though using a weather disaster record for crop impact analyses has limitations, it offers a unique and standardized metric indicating that, at the EU level, climate change is already driving increasing crop losses in observational records. Understanding the effects of EWD on crop responses in the past and present climate contributes to the discussion of strategies and priorities in view of improving food systems resilience, including on the potential role of trade policies to support adaptation actions

Severity of drought and heatwave crop losses tripled over the last five decades in Europe

Extreme weather disasters (EWDs) can jeopardize domestic food supply and disrupt commodity markets. However, historical impacts on European crop production associated with droughts, heatwaves, floods, and cold waves are not well understood—especially in view of potential adverse trends in the severity of impacts due to climate change. Here, we combine observational agricultural data (FAOSTAT) with an extreme weather disaster database (EM-DAT) between 1961 and 2018 to evaluate European crop production responses to EWD. Using a compositing approach (superposed epoch analysis), we show that historical droughts and heatwaves reduced European cereal yields on average by 9% and 7.3%, respectively, associated with a wide range of responses (inter-quartile range +2% to −23%; +2% to −17%). Non-cereal yields declined by 3.8% and 3.1% during the same set of events. Cold waves led to cereal and non-cereal yield declines by 1.3% and 2.6%, while flood impacts were marginal and not statistically significant. Production losses are largely driven by yield declines, with no significant changes in harvested area. While all four event frequencies significantly increased over time, the severity of heatwave and drought impacts on crop production roughly tripled over the last 50 years, from −2.2% (1964–1990) to −7.3% (1991–2015). Drought-related cereal production losses are shown to intensify by more than 3% yr−1. Both the trend in frequency and severity can possibly be explained by changes in the vulnerability of the exposed system and underlying climate change impacts

Severity of drought and heatwave crop losses tripled over the last five decades in Europe

Publisher Copyright: © 2021 The Author(s). Published by IOP Publishing Ltd.Extreme weather disasters (EWDs) can jeopardize domestic food supply and disrupt commodity markets. However, historical impacts on European crop production associated with droughts, heatwaves, floods, and cold waves are not well understood - especially in view of potential adverse trends in the severity of impacts due to climate change. Here, we combine observational agricultural data (FAOSTAT) with an extreme weather disaster database (EM-DAT) between 1961 and 2018 to evaluate European crop production responses to EWD. Using a compositing approach (superposed epoch analysis), we show that historical droughts and heatwaves reduced European cereal yields on average by 9% and 7.3%, respectively, associated with a wide range of responses (inter-quartile range +2% to -23%; +2% to -17%). Non-cereal yields declined by 3.8% and 3.1% during the same set of events. Cold waves led to cereal and non-cereal yield declines by 1.3% and 2.6%, while flood impacts were marginal and not statistically significant. Production losses are largely driven by yield declines, with no significant changes in harvested area. While all four event frequencies significantly increased over time, the severity of heatwave and drought impacts on crop production roughly tripled over the last 50 years, from -2.2% (1964-1990) to -7.3% (1991-2015). Drought-related cereal production losses are shown to intensify by more than 3% yr-1. Both the trend in frequency and severity can possibly be explained by changes in the vulnerability of the exposed system and underlying climate change impacts.publishersversionpublishe