What effects are extreme weather events having?
Certain types of extreme weather events have increased significantly worldwide. The warming that scientists have observed to date has already led to longer and more frequent heat waves of greater intensity in most areas on land. In some areas, droughts have also become more frequent and severe, such as in the Mediterranean region, West Asia, many parts of South America, and much of Africa and Northeast Asia. In addition, local heavy precipitation has intensified further all across the globe.¹
In northwestern Europe, the risk of river floods has gone up in recent decades.² And although the total number of tropical storms has not increased, the most severe tropical storms have become more frequent: Between 1979 and 2017, the percentage of storms with hurricane force (as determined by satellites) in the strongest categories of 3, 4, or 5 as compared to all hurricane-force storms increased by a quarter, from 32 percent to 40 percent.³
Rising temperatures, changing precipitation patterns, and the increase in some weather extremes have already begun to compromise food security. For example, corn and wheat yields have fallen in many regions close to the equator (while regions in higher latitudes have seen better harvests). In Africa, climate change is already hurting livestock production.⁴
¹ IPCC 2019, SRCCL, SPM, A2.2 – https://www.de-ipcc.de/media/content/SRCCL-SPM_de_barrierefrei.pdf
² Blöschl et al. 2019: https://www.nature.com/articles/s41586-019-1495-6
³ Kossin et al. 2020 - https://www.pnas.org/content/117/22/11975 https://www.gfdl.noaa.gov/global-warming-and-hurricanes/; IPCC 2019, SROCC, Kap. 6 – https://www.ipcc.ch/site/assets/uploads/sites/3/2019/11/10_SROCC_Ch06_F…
⁴ IPCC 2019, SRCCL, SPM, A2.8 – https://www.de-ipcc.de/media/content/SRCCL-SPM_de_barrierefrei.pd