7.6    WRF-Chem Studies of Aerosols and Chemistry Over the Indian Subcontinent During the Ganges Valley Experiment (GVAX)

Feng, Yan, Argonne National Laboratory, and V. Rao Kotamarthi, Argonne National Laboratory

 

The Ganges Valley region in northern India has been observed to have high aerosol and ozone concentrations. During the pre-monsoon season and during the monsoon season, trace gases and aerosols can be elevated by strong convection to the mid- and upper troposphere. These pollutants could have a significant impact on regional climate. It has also been hypothesized that the build-up of aerosols in the dry winter may affect the onset and intensity of the summer monsoon.  The Ganges Valley Aerosol eXperiment (GVAX) conducted a 9-month observation at Nainital, India, from July 2011 to March 2012, using the Department of Energy (DOE) Atmospheric Radiation Monitoring (ARM) mobile facility.  Measurements of ozone, aerosol concentration, vertical profiles, cloud liquid water path and convection were made. 

The focus of the present study is to examine concentration and vertical distribution of aerosol and ozone during the monsoon to post-monsoon months (July to December). We will present the WRF-Chem simulations over the Indian subcontinent, and test two deep convection schemes implemented in the WRF-Chem (Grell vs Zhang-McFarlane) on the vertical transport of tracers. We will also present preliminary evaluation of aerosol vertical transport using the ground-based profiling of aerosol extinction, cloud liquid water, water vapor, and temperature at Nainital.