Stratosphere-Troposphere Coupling Studies

Northwest Research Associates, Incorporated, Seattle WA

Investigators

Abstract

This project will investigate how the stratosphere acts as an integrator of high-frequency-wave forcing from below, creating long-lived circulation anomalies in the lower stratosphere which feed back to affect tropospheric weather and climate. Three major questions to be addressed by this research are: 1) What are the stratospheric effects at Earth's surface? 2) As climate changes, what will the effects be on climate? 3) By what mechanisms are stratospheric effects communicated to Earth's surface? The work will be performed using a combination of observations and models, and will focus on understanding those dynamical mechanisms via which stratospheric circulation anomalies are communicated to the Earth's surface. Direct and indirect effects, coupled with planetary and synoptic-scale waves, are believed to make significant contributions. The relationship of stratosphere-troposphere coupling to the quasi-biennial oscillation, the El Nino Southern Oscillation, and the position of the subtropical jet, will also be studied. This project is expected to result in further advances in understanding the long-term changes in weather and climate, and therefore has important practical benefits to society.