Ozone Photochemistry in China: Field Measurements and Modeling Analysis

Georgia Tech Research Corporation, Atlanta GA

Investigators

Abstract

This project is a continuation of an effort to better understand the ground level photochemistry that causes the formation of ozone, a pollutant with adverse effects on human health. Measurements of ozone precursors will be made as part of an international study named The Campaigns of Air Pollution Research in Megacity - Beijing and the North China Plain. This is a follow-on campaign to one that took place in August 2007 and will include scientists from France, Japan, Germany, Hong Kong, and the USA, as well as from China. Understanding ozone photochemistry over China is important to understanding global photochemistry. Both photochemical and transport modeling will be conducted to analyze the photochemistry and in-situ production of ozone at the site. Several issues related to the local photochemistry will be further analyzed. These include the investigation of key pathways for heterogeneous production of nitrous acid and for the loss of hydroperoxyl radicals onto aerosol surfaces. Data from the in situ and satellite measurements will be analyzed using the 3-D Regional chEmical trAnsport Model (REAM). Model simulations of photochemical reactions will be conducted, constrained by the concentrations of long-lived species and observations of intermediate species such as peroxyacetyl nitrate, peroxynitric acid, and glyoxal. The research results of this effort will be used to update some of the photochemical mechanisms used in the model.