Applications of satellite retrievals in deriving pollutant emissions and trends

Ruixiong Zhang
Thursday, November 2, 2017 - 10:00am
ES&T Room L1114
Dr. Yuhang Wang (Advisor), Dr. Greg Huey, Dr. Nga Lee Ng, Dr. Rodney Weber, Dr. Jintai Lin (Peking University)

This dissertation employs various satellite retrievals and the 3-D Regional chEmical trAnsport Model (REAM) to (1) identify and quantify the emission sources, and (2) derive pollutant trends.

First, we use short-lived reactive aromatics as proxies to diagnose transport of pollutants through the Himalayas to Tibet. We find enhancements of reactive aromatics over Tibet by a factor of 6 on average due to rapid transport from India and nearby regions during the presence of a high-altitude cut-off low system.

Second, we derive anthropogenic NOx emissions with 4km spatial resolution using Ozone Monitoring Instrument (OMI) NO2 retrieval in Yangtze River region during June-July-August (JJA) of 2005-2009 and 2010-2015. The NO2 emission inversion using High-resolution Daily Retrieval-Inversion (HDRI) method proves powerful in quantifying the effects of urbanization.

Finally, we retrieve OMI tropospheric NO2 VCDs and obtain the NO2 relative trends over the United States. We improve the OMI retrievals for trend analysis by removing the ocean trend, using MODerate-resolution Imaging Spectroradiometer (MODIS) albedo data in air mass factors (AMFs) calculation, and applying lightning event filter to screen data. These improvements result in close agreement (within 0.8% yr-1) between EPA AQS in situ and OMI-based NO2 annual relative trends.