インド洋における積雲活動の形態

Abstract

On the cumulus activity in the Indian Ocean, the outgoing longwave radiation data from the satellites were analyzed, centered on the interannual change of the tropical 30-60 day variation. The main results are following: (ⅰ) Near the equator, the cumulus activity is large all the year in the Indian Ocean. (ⅱ) The most dominant mode of the interannual change of the OLR is accompanied by El Niflo Event. However, the patterns of OLR in the two separated Event differ much. No other clear largescale interannual change mode can be attained. (ⅲ) The amplitude of the 30-60 day variation near the equator is large in usual years even in the Northern

Southern summer. However, in several Northern Summer, the 30-60 day variation is suppressed near the equator and the center of it moves to 10-15ﾟN, though the cumulus activity is normal.