Global Budgets of Atmospheric Trace Gases

该项目涉及三维化学输运模式模拟和大气观测分析，重点关注几种重要大气微量气体的全球预算。具体活动将侧重于：(1)汞的全球预算，包括来源、与地表水库的交换和化学转化，目的是提高我们对人为影响和来源-受体关系的理解；(2)甲醇、丙酮和乙醛的预算及其对大气化学的影响，利用最近和正在进行的飞机运动的测量结果（ICARTT、MILAGRO、INTEX-B）；(3)羰基硫化物（OCS）的全球收支，重点是量化源汇过程，并评估人为影响。该项目将在大气观测分析中结合正演和逆演模式。将基于源和汇的最佳先验估计的正演模式模拟与观测到的浓度统计数据进行比较，以检验对过程的基本理解。在分析汞和OCS预算时将使用逆模型，以便根据大气观测提供的限制条件优化个别预算项的幅度。本项目将为研究生提供获得大气化学建模方法训练的机会。这项研究的结果将通过提高对重要大气过程的基本理解而造福社会。考虑到与健康有关的问题，关于汞的研究结果将是有益的。

This project involves 3-dimensional chemical transport model simulations and analysis of atmospheric observations, focusing on the global budgets of several important atmospheric trace gases. Specific activities will focus on:(1) the global budget of mercury including sources, exchange with surface reservoirs, and chemical transformations, with the goal of improving our understanding of anthropogenic influences and source-receptor relationships;(2) the budgets of methanol, acetone, and acetaldehyde, and their implications for atmospheric chemistry, making use of measurements from recent and ongoing aircraft campaigns (ICARTT, MILAGRO, INTEX-B); and(3) the global budget of carbonyl sulfide (OCS) with focus on quantifying source and sink processes, and assessing the anthropogenic influence. The project will involve a combination of forward and inverse modeling in the analysis of atmospheric observations. Forward model simulations based on best a priori estimates of sources and sinks will be compared to observed concentration statistics to test the basic understanding of processes. Inverse modeling will be used in the analyses of mercury and OCS budgets to optimize the magnitudes of individual budget terms on the basis of the constraints offered by atmospheric observations.This project will provide opportunities for graduate students to obtain training in the methods of atmospheric chemistry modeling. The results of the study will benefit society by improving the fundamental understanding of important atmospheric processes. The results on mercury will be of benefit because of the health-related concerns.