Future changes in extreme heatwaves in terms of intensity and duration over the CORDEX-East Asia Phase Two domain using multi-GCM and multi-RCM chains

Abstract An extreme heatwave, in terms of intensity and duration, is projected to occur at the end 21st century (2071–2100) over whole East Asia. The projection calculated using daily maximum temperature data 25 km horizontal resolution produced by 12 general circulation model-regional climate model chains participating CORDEX-East Asia Phase 2 project. ‘extreme’ heatwave defined as one which magnitude (HWM), accumulated a during period, higher than 95th percentile HWM for reference period (1981–2005). In historical simulations, heatwaves have occurred mainly from April June India, May Indochina, August China Mongolia, July Korean Peninsula Japan; most last three four days. India long-lasting intense more often other regions. future, will increase, average duration be approximately two weeks, season lengthened. Therefore, frequently strongly. Under representative concentration pathway scenarios (RCP2.6 RCP8.5) shared socioeconomic (SSP1-2.6 SSP5-8.5), proportion all events increase 5.0% (historical) 8.0%, 20.8%, 19.3%, 36.3%, 1.4, 3.5, 3.0, 9.0 times stronger, respectively. main reason increased rather heatwaves. Asia, temporal regional disparities damage much prominent become stronger frequent these regions periods that are affected present day.