Widespread hot extremes are seen across the world in recent years, causing heat-related mortality and harmed crops and livestock. In summer 2018, a record-breaking heat wave swept large areas of Northeast Asia. The China Meteorological Administration issued high-temperature warnings for 33 consecutive days. In Japan, at least 71,266 required hospitalization for heat stroke.
To make it worse, 2018 heat wave was probably not a random or an individual case according to a new study published in Environmental Research Letters. In the study, 2018 heat wave is used as a rear-view mirror to investigate what has caused more extreme summer heat event over Northeast Asia, and in particular, to look into the role of anomalous anticyclone over Northeast Asia.
An anticyclone is an area of high atmospheric pressure, which causes settled weather conditions, and, in summer, clear skies and high temperatures. But how much the anomalous anticyclone circulation would contribute to extreme heat event over Northeast Asia, still remains unknown.
"Our study, for the first time, gave a quantitative estimation of the contribution of circulation to such a heat event over Northeast Asia, by using the flow analogue method," says REN Liwen, the lead author, a Ph.D student from Institute of Atmospheric Physics at Chinese Academy of Sciences and University of Chinese Academy of Sciences. "We found that anomalous anticyclone over Northeast Asia were responsible for nearly half of the magnitude in extreme heat event of 2018."
Read more at Institute of Atmospheric Physics, Chinese Academy of Sciences
Image: More frequent heatwaves over Northeast Asia since 1990s. (Credit: Liwen Ren)