Diurnal cycle of precipitation over the eastern Indian Ocean off Sumatra Island during different phases of Indian Ocean Dipole

Observed difference in diurnal cycle of precipitation over the eastern Indian Ocean between positive and negative Indian Ocean Dipole (IOD) phases was investigated using a regional model. During the negative IOD phase, prominent precipitation peak was over the land during evening in both observation and model, while precipitation often appeared over the ocean during early morning. In the positive IOD phase, precipitation peak was shifted to the northern area where sea surface temperature was warm. The amount of precipitation in the southern area during the negative phase was more than three times larger than that in the positive phase.