A pronounced continental-scale diurnal mode of the Asian summer monsoon

A pronounced continental-scale diurnal mode of the Asian summer monsoon is mapped using data from recent satellites Meteosat-5 and TRMM. These dataset s were available at high temporal resolutions. A result that stands out is the diurnal divergent circulation that in the afternoon hours has an ascend ing lobe over north-central India and has a descending lobe that reaches ou r radially toward central China, the southern parr of China, the equatorial Indian Ocean, and the western Arabian Sea. The reverse circulation is clea rly seen during the early morning hours. This diurnal pulsation of continen tal-scale divergent circulation appears to be an integral part of the monso on. Another finding relates to th diurnal slowing down and speeding up of t he Tibetan high circulations, especially in the southern flanks where the t ropical easterly jet resides and exhibits a pulsation of intensity. The amp litude of pulsation was found to reach up to 7 m s(-1). Thus this continent al-scale change appears to be a pronounced feature. The phase and amplitude of various satellite datasets derived from the 90-min datasets are also di splayed to confirm this major mode, that is, the diurnal oscillation of mon soon.