Diurnal and seasonal variation of planetary boundary layer height over East Asia and its climatic change as seen in the ERA-5 reanalysis data

Abstract The diurnal/seasonal structure of the boundary layer height (BLH) is investigated over East Asia by using hourly synoptic monthly ERA5 reanalysis variables from 1979 to 2019. Sensible heat flux (SHF) major factor in temporal and spatial variation BLH. Although BLH, general, positively correlated with SHF throughout year, BLH-SHF relationship varies significantly based on surface type, latitude time year. Analysis also reveals that stability an important parameter controlling diurnal maximum growth BLH strongly limited presence a stable layer. On other hand, increases abruptly weakly stratified residual In addition, regional warming tends increase mid- high-latitude continental area. low-latitude area, sign anomalous seasonally regionally. Stability plays only minor role change except Tibetan Plateau, where increased at top due reduces rather significantly.