Dynamical and Chemical Diagnosis of Stratosphere-Troposphere Analyses of Regional Transport 2008 (START08) Data

对流层空气的侵入可以对温带平流层下层辐射活性微量气体的浓度产生重大影响，从而对全球能量平衡产生重大影响。本项目将利用现场观测和模式模拟分析热带对流层上层空气向温带平流层下层的输送。它将使用国家大气研究中心(NCAR)/国家科学基金会（NSF）湾流V （GV）飞机在2008年平流层-对流层区域运输分析（START08）现场项目中收集的数据，研究对流层上层和平流层下层（UT/LS）的运输及其对大气成分的影响。该研究将描述START08期间对流层侵入的组成、频率、位置和强度。采用轨迹分析、痕量物质分析和多痕量物质间的关联等方法建立气团和混合特性。动力学系统方法将用于研究不可逆输运事件的详细结构并绘制其发生图。START08数据还将用于评估NCAR全大气群落气候模式（WACCM）模拟化学和输送的性能。这项研究将促进我们对UT/LS的动力学、化学和辐射过程的科学理解，并有可能改进人为气候变化的模式模拟。对START08数据的分析也将推进GV飞机作为一种高性能观测系统的发展。本计划亦有助发展科学人力资源，培养研究生从事研究工作，并为本科生日后的研究生学习或技术工作作准备。

Intrusions of tropospheric air can have a significant effect on the concentrations of radiatively active trace gases in the extratropical lower stratosphere and thus on the global energy balance. This project will analyze the transport of tropical upper tropospheric air into the extratropical lower stratosphere using in situ observations and model simulations. It will use data collected by the National Center for Atmospheric Research (NCAR)/National Science Foundation (NSF) Gulfstream V (GV) aircraft during the Stratosphere-Troposphere Analyses of Regional Transport 2008 (START08) field program to study transport in the upper troposphere and lower stratosphere (UT/LS) and its impact on atmospheric composition. The research will characterize the composition, frequency, location, and magnitude of tropospheric intrusions during the START08 period. The methods to be applied include trajectory analysis, trace species analysis, and correlations between multiple trace species to establish source air mass and mixing properties. Dynamical systems methods will be used to study the detailed structure of irreversible transport events and map their occurrence. The START08 data will also be used to evaluate the performance of NCAR Whole Atmosphere Community Climate Model (WACCM) simulations of chemistry and transport.This research will advance our scientific understanding of dynamical, chemical, and radiative processes in the UT/LS, which has the potential to improve model simulations of anthropogenic climate change. Analysis of the START08 data will also advance the development of the GV aircraft as a high-capability observing system. This project will also contribute to the development of human resources in science by training graduate students for research careers and preparing undergraduate students for future graduate study or technical careers.