Further Calculations of Sea Level Air Trajectories over the Equatorial Indian Ocean

Abstract

Quasi-horizontal 48 h air trajectories were constructed over the equatorial Indian Ocean utilizing a mean sea level pressure map for July and a series of daily pressure maps in June 1970. The purposes of this calculation were 1) to determine whether the broad-scale equatorial (20°?20°S) pressure fields would induce strong cross-equatorial flow in terms of trajectories of air motion. 2) to examine the typical magnitudes of some of the forces governing the courses of the computed trajectories, and 3) to derive the vorticity and divergence fields from the computed trajectories and compare them against the synoptic features and satellite cloudiness. The results showed that representative trajectories of the low-level monsoon flow could be calculated. Furthermore, the derived vorticity and divergence field showed fair association with the significant synoptic features.