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

Economic incentives modify agricultural impacts of a regional nuclear war concerning food insecurity and famine

A nuclear war using less than 1% of the current global nuclear arsenal could produce climate change unprecedented in recorded human history and large impacts on agricultural productivity. These e↵ects would be most severe for the first five years after the nuclear war and may last for more than a decade. This paper calculates how the price and availability of food worldwide would change by employing the Environmental Impact and Sustainability Applied General Equilibrium model. It evaluates how results depend on assumptions about how free trade would continue in a post-war economic environment. The results suggest that preserving the world trading system is key to preventing widespread food shortages as a thriving world trading system minimizes the costs born from disruptions to climate. The analysis shows that the regional nuclear war scenario would a↵ect regional food supply systems, especially in high latitude regions. Although the global average impact on wheat is only a few percentage points, the regional nuclear war leads wheat production in EU 28 countries to plumed, on average, by more than 15%. The model also suggests that regional impacts may result in a plausible domino e↵ect with substantial negative ramifications for local food supplies

Assessing the impacts of 1.5°C global warming - Simulation protocol of the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP2b)

In Paris, France, December 2015, the Conference of the Parties (COP) to the United Nations Framework Convention on Climate Change (UNFCCC) invited the Intergovernmental Panel on Climate Change (IPCC) to provide a special report in 2018 on the impacts of global warming of 1.5ĝ€°C above pre-industrial levels and related global greenhouse gas emission pathways. In Nairobi, Kenya, April 2016, the IPCC panel accepted the invitation. Here we describe the response devised within the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP) to provide tailored, cross-sectorally consistent impact projections to broaden the scientific basis for the report. The simulation protocol is designed to allow for (1) separation of the impacts of historical warming starting from pre-industrial conditions from impacts of other drivers such as historical land-use changes (based on pre-industrial and historical impact model simulations); (2) quantification of the impacts of additional warming up to 1.5ĝ€°C, including a potential overshoot and long-term impacts up to 2299, and comparison to higher levels of global mean temperature change (based on the low-emissions Representative Concentration Pathway RCP2.6 and a no-mitigation pathway RCP6.0) with socio-economic conditions fixed at 2005 levels; and (3) assessment of the climate effects based on the same climate scenarios while accounting for simultaneous changes in socio-economic conditions following the middle-of-the-road Shared Socioeconomic Pathway (SSP2, Fricko et al., 2016) and in particular differential bioenergy requirements associated with the transformation of the energy system to comply with RCP2.6 compared to RCP6.0. With the aim of providing the scientific basis for an aggregation of impacts across sectors and analysis of cross-sectoral interactions that may dampen or amplify sectoral impacts, the protocol is designed to facilitate consistent impact projections from a range of impact models across different sectors (global and regional hydrology, lakes, global crops, global vegetation, regional forests, global and regional marine ecosystems and fisheries, global and regional coastal infrastructure, energy supply and demand, temperature-related mortality, and global terrestrial biodiversity)