Interhemispheric Transport: Mechanistic Studies for Understanding and Improving 3-D Chemical Models

标题：半球间运输：理解和改进三维化学模型的机制研究提案研究的主要目标是获得对控制半球间空气包裹交换的机制的更好理解：该信息将用于改进目前不能充分模拟半球间交换的三维化学运输模型。对于某些模型，这将涉及明确地评估和改进模型动力学。然而，对于使用预先确定的风场的传输模式，所涉及的过程的参数化是必要的。为了实现这些目标，将结合对观测和一般环流模式输出的分析来研究跨赤道运输的主要位置、季节性和年际变率。还将进行研究，以诊断与半球之间质量交换有关的动力学过程。实现这些目标的具体步骤包括分析社区气候模式2 （CCM2）在气候海表温度（SSTs）强迫下完成的CFCl3输运模拟，以确定半球间输运的位置和季节性。该项目还将以CFCl3为示踪剂对CCM2进行运行，利用观测到的海温来研究厄尔尼诺/南方涛动（ENSO）对半球交换年际变化的影响。在对参数化进行测试后，它将可用于化学输运模型的一般用途。

Abstract ATM-9401216 Hartley, Dana Georgia Tech Title: Interhemispheric Transport: Mechanistic Studies for Understanding and Improving 3-D Chemical Models The primary goal of the proposal research is to obtain an improved understanding of what mechanisms control the exchange of air parcels between hemispheres: This information will be used to improve 3-D chemical transport models that presently do not adequately simulate interhemispheric exchange. For some models this will involve explicitly assessing and improving the model dynamics. However, for transport models that use predetermined wind fields a parameterization of the processes involved will be necessary. In order to achieve these goals, a combination of analyses of both observations and general circulation model outputs will be employed to study the dominant locations, seasonality, and interannual variability of cross-equatorial transport. Studies will also be performed to diagnose the dynamical processes related to the exchanged of mass between hemispheres. The specific steps to meet these goals include analyzing previously completed simulations of CFCl3 transport in the Community Climate Model 2 (CCM2) forced with climatological sea surface temperatures (SSTs) to determine the location and seasonality of the transport between hemispheres. The PI will also perform runs of the CCM2, with CFCl3 as the tracer, using observed SSTs to examine the influence of the El Nino/South Oscillation (ENSO) on interannual variability of interhemispheric exchange. After the parameterzation has been tested, it will be available for general use in chemical transport models.