[A-HW21] Interdisciplinary approach to support climate change adaptation measures in regional scale

[AHW21-04] The impact of sensible heat and latent heat on monsoon onset over Indochina peninsula

Tomohito Yamada¹, Ryosuke Kato¹, *Sourabh Shrivastava¹ (1.Hokkaido University )

Keywords:Monsoon onset, Sensible Heat, latent heat

In this study, interannual variations of the summer monsoon onset over the Indochina Peninsula were studied using the CPC Merged Analysis of Precipitation (CMAP) panted rainfall and NCEP reanalysis data from 1979 to 2016. For the climatological onset over Indochina Peninsula, 27^th panted is considered. Equal numbers (9-9) of early and late monsoon onset years are identified during the last 3 decades. Sensible heat flux (Q1) and latent heat flux (Q2) influence the atmospheric circulation over the Indochina peninsula during monsoon onset. Composite analysis of Q1 and Q2 shows that the large change in Q1 and Q2 over the mainland of Indochina peninsula during early (late) monsoon years. The positive Q1 and Q2 anomalies suggest the strong convection in the early monsoon over the Indochina peninsula. It seems to be a dipole pattern over the mainland of the Indochina peninsula and the eastern Indian Ocean, where north-central Thailand have a positive (negative) anomaly and the eastern Indian Ocean have a negative (positive) anomaly during early (late) monsoon onset. Results also suggested the strong cyclonic flow at 850 hPa winds associated with the rainfall over the Indochina peninsula during early monsoon onset.