A study of south-westward propagating wave activities over the western Pacific during YMC-BSM 2018

Abstract:

The Maritime Continents are a region of large convective activities and many disturbances are generated from a local region such as convection and topography. In these regions, the Campaign of Years of the Maritime Continent (YMC) has been operated from November 2017 to expedite the progress of improving understanding and prediction of local multi-scale variability of the Maritime Continent weather-climate system and its global impact. The ultimate goal of this study is to develop a method for analyzing three-dimensional (3D) wave-driven material transport and to capture the dynamical effects to minor constituents such as ozone in detail. Prior to that, this presentation focuses on south-westward propagating disturbances seen near the Philippines in July 2018 (YMC-Boreal Summer Monsoon: BSM campaign) as a case study analysis, and reports on the characteristics of the disturbances and their relationships with convections.

Using the ERA-Interim reanalysis data, we found that

1: South-westward propagating disturbances are frequent during this period at 500-100 hPa.

2: A strong upward and south-westward propagating disturbance was observed in the northeast of the Philippines during 4-8 July, interacting with the nearby Typhoon MARIA.

Future analyses will focus on the relation between south-westward propagating disturbances and strong convective activity, including the typhoon, during June and August 2018.