Due to global warming, heatwave events will likely cause severe damage to natural ecosystems and human society. Urban areas are at higher risk due to increasing economic activities and resident populations. As such, it is important to understand the characteristics of recent changes in heatwave patterns.
The year of 2019 is one of the warmest years globally since 1850. Although several studies have attempted to examine the heatwave events that took place in 2019 across the globe, there is still limited understanding regarding heatwave hotspot regions in Africa, particularly their spatial link with urban areas.
Recently, researchers from the Institute of Atmospheric Physics (IAP), Chinese Academy of Sciences, integrated climate reanalysis, satellite and population data to quantify heatwave hotspots in 2019 over Africa.
The researchers found that there was a major shift in the spatial distribution of heatwave hotspots from the equatorial region in the baseline period (1981–2010) to large areas up to the temperate climate zones (above 30°N and 30°S) in 2019, affecting more urban agglomerations.
The proportion of urban populations exposed to extreme heatwaves in the Northern Hemisphere and Southern Hemisphere rose from 4% and 15%, respectively in the baseline period, to 36% and 57%, respectively in 2019.
Overall, the heatwave hotspots of 2019 in Africa were accompanied by seasonal changes in atmospheric circulation and above-normal sea surface temperature, likely as a result of large-scale forcing due to climate change.
"These findings are significant for human health, energy consumption, and water security in developing and vulnerable regions such as Africa that are experiencing population growth but have low adaptive capacity," said Prof. JIA Gensuo, corresponding author of the study.
