Global Budgets of Atmospheric Trace Gases

该项目涉及对大气观测的三维化学输送模型模拟和分析，重点是几个重要的大气痕量气体的全球预算。具体活动将侧重于：(1)汞的全球预算，包括源、与地表水库的交换和化学转化，目的是增进我们对人为影响和源-受体关系的了解；(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活动(ICARTT、Milagro、INTEX-B)的测量；以及(3)羰基硫化物(OCS)的全球预算，重点是量化来源和汇过程，并评估人为影响。该项目将在大气观测分析中结合使用正演和逆演模拟。基于对源和汇的最佳先验估计的正演模式模拟将与观测浓度统计数据进行比较，以检验对过程的基本理解。在汞和OCS预算的分析中将使用反向建模，以根据大气观测提供的限制来优化各个预算项的大小。该项目将为研究生提供大气化学建模方法方面的培训。这项研究的结果将增进对重要大气过程的基本了解，从而使社会受益。由于与健康相关的担忧，有关汞的结果将是有益的。

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.