A preliminary study of cloud clusters in the near-equatorial regions of south Indian Ocean during southwest monsoon season

Abstract

The occurrence, characteristics and movement of cloud clusters within the latitude belt equator to l5^oS over the Indian Ocean during the period 1 May to 31 July 1973 have been studied in this paper, utilizing the daytime visible channel satellite cloud imagery received from NOAA-2 spacecraft. It is found that cloud clusters mainly occur east of latitude 60^oE and that their number generally increases from west to east. They have the maximum frequency of Occurrence in the latitude belt equator to 5⁰S. The cloud clusters are predominantly amorphous in shape, indicating that mostly weak low pressure systems occur in this region. Their lire period ranges upto 8 days but most of them have a life period of less than 2 days. A majority of those having a life period of 2 days or more show a westward or northwestward movement, with a tendency to recurve northeastward subsequemly, as theyapproach the equator.