Qing Liang (NASA Goddard)

Qing Liang (NASA Goddard)
Monday, October 18, 2021 - 12:00pm to 1:00pm

Surface to the Upper Troposphere/Lower Stratosphere Transport: A perspective from chemical trace constituents

The upper troposphere and lower stratosphere (UT/LS) are important dynamically and chemically. Dynamically, the UT/LS is of major interest because it is the interface between two very different regimes, the troposphere and the stratosphere, where air from these regimes mix and circulate.  Chemically, surface to the UT/LS transport of trace gases can affect atmospheric abundance of ozone, the hydroxyl radical (OH), and aerosols, which are key chemical constituents that exert significant impact on stratospheric composition and climate. Besides the traditionally recognized Western Pacific warm pool being a primary convective lofting region for troposphere-to-stratosphere transport (TST), the Asian Summer Monsoon and N. American Monsoon regions also play important roles in delivering surface pollutants into the UT/LS.  Our recent finding during the NSF/NASA Asian Summer Monsoon Chemical and Climate Impact Project (ACCLIP) suggests that, albeit occur less frequently, deep convective lofting in strong tropical cyclones (typhoons and hurricanes) can impact the UT/LS chemical composition as well.

In this presentation, I will show my research results in combining the NASA Goddard GEOS Chemistry Model and airborne observations of trace gases from several NASA/NSF field campaigns (CONTRAST, ATTREX, TC4, SEAC4RS, ACCLIP) to examine surface to UT/LS transport in the deep convection regions, i.e., the Western Pacific, Asian Summer Monsoon, and North and Central America. I will demonstrate how an idealized tracer, i.e., age of air, and trace gases of different lifetimes and chemical processes, e.g., CO and volatile organic compounds (VOCs), can be combined to elucidate transport processes, transport timescale, and vertical lofting efficiency in these deep convection centers.  I will also discuss some interesting chemical findings learned during these analyses.

About this Series:

The PAOC Colloquium [PAOCC] is a weekly interdisciplinary seminar series that brings together the whole PAOC community. Seminar topics include all research concerning the physics, chemistry, and biology of the atmospheres, oceans and climate, but also talks about e.g. societal impacts of climatic processes. The seminars take place on Monday from 12-1pm. Besides the seminar, individual meetings with professors, post-docs, and students are arranged. Contact: paoc-colloquium-comm@mit.edu.