Multiscale variability of the tropical tropopause layer during AMIE

Poster PDF

Description

The interface between the troposphere and the stratosphere is best described as a transition layer with characteristics of both the troposphere and the stratosphere. In the tropics, this region is known as the tropical tropopause Layer (TTL). The TTL extends from the level of main convective outflow (~200 hPa) to the lower stratosphere (~ 70 hPa). It sets the boundary conditions for atmospheric tracers entering the stratosphere. Specifically, TTL temperatures control stratospheric water vapor concentrations, which play a key role in the radiative budget of the stratosphere. The ARM Madden-Julian Oscillation (MJO) Investigation Experiment (AMIE), along with companion field campaigns Dynamics of the Madden-Julian Oscillation (DYNAMO) and Cooperative Indian Ocean experiment on intraseasonal variability in the Year 2011 (CINDY2011), offers a broad suite of data sets in the location of the origin of the MJO to investigate tropical convective systems over wide-ranging time scales and their impact on the tropopause and TTL. Here we present initial analysis of the response of TTL temperatures and winds to the MJO passages based on the intense high-resolution sounding observations on Gan from October–December 2011. In particular we analyze the characteristics of the observed wave structures and their impact on TTL structure and relate these to the observed deep convective and cirrus clouds.