Atmospheric Teleconnection Dynamics of North Atlantic Cooling to the Tropical Climate

University Of California-Berkeley, Berkeley CA

Investigators

Abstract

This project seeks to understand the processes through which the cooling of the extratropical North Atlantic results in a weakening of the North African and Asian monsoons. The weakening of the monsoons in response to North Atlantic cooling is suggested in paleoclimate evidence from the last glacial period, and is also relevant to 20th century climate change including the decades-long Sahel drought. Work under this award will examine the teleconnection between North Atlantic cooling and the monsoon systems through simulations with a simplified climate model, in which the ocean component model is replaced with a "slab ocean" which represents ocean thermodynamics but not dynamics. Preliminary work shows that the model is capable of reproducing the teleconnection, and the research will consist of diagnostic analysis of model output, combined with a suite of model experiments, to identify the primary mechanisms through which the influence of North Atlantic cooling is communicated to the monsoon regions. In addition to its scientific interest, the question addressed here has societal relevance due to the large number of people who live in the monsoon regions of Asia and North Africa. In addition, the project will support and train a graduate student, thereby providing for the next generation of scientists engaged in this research area.