Influence of Convective Heating Over the Maritime Continent on the West Antarctic Climate

Abstract

The Maritime Continent (MC) is regarded as an important heat source region and the impact of MC heating on the West Antarctic climate which is largely controlled by the Amundsen Sea Low (ASL) is unknown. This study is focused on the impact of intensified convective heating over the MC on the variation of the ASL in the austral fall. It is observed that enhanced MC heating is linked to deepening of the eastern ASL, a feature reproduced successfully by a model experiment in which additional heating is introduced to the MC. The intensified MC heating generates anticyclonic anomalies that result in a Rossby wave source in the upper troposphere to the south of MC. Then the Rossby wave originated from the new source propagates southeastward and deepens the eastern ASL. Additional model experiments prove that the response of ASL to MC heating is stronger than that to central Pacific cooling.