Infrared Measurements of Atmospheric Composition over Antarctica

拟议的项目是在麦克默多和南极利用被动红外仪器制定一项大气化学观测方案。测量将在两年中全年进行，并将为光化学传输模型提供更多更好的数据和限制。由于这些模型用于预测未来的臭氧消耗和气候变化，因此必须尽可能准确。南极臭氧空洞已经显示了南极平流层对氯的敏感性，预计空洞的逐渐愈合将标志着政策的成功。然而，模型预测表明，由于全球变暖对催化臭氧破坏过程的影响，恢复可能会延迟。由于目前大多数卫星仪器在冬季不对极地地区进行采样，地面仪器可作出重要贡献，拟议仪器的数据也将为新的卫星传感器提供验证。这些仪器是在Arrival Heights（与新西兰国家水和空气研究所合作）和南极运行的四台傅里叶变换光谱仪。其中两个FTS（0.1-1.0厘米分辨率的大气排放）将被放置在南极和麦克默多，用于全年运行，一个0.003厘米-1分辨率的太阳能FTS将被部署在南极，在夏季运行。排放仪器将在极夜期间提供关于HNO 3和脱氮以及脱水的重要信息。传输FTS的将提供高分辨率的光谱，我们将从中获得的垂直配置文件，以及垂直柱量的臭氧破坏过程中重要的许多分子，以及大气示踪剂，如HF。来自排放仪器的光谱将提供HNO 3、CH 4、O3、H2O、N2 O、CFC、ClONO 2和NO2在转化为其他奇数氮之前的全年柱丰度测量。太阳能仪器还将提供有关这些分子以及HCl、ClONO 2、NO、NO2、HNO 3、HF和其他分子的高度分布信息。所获得的光谱数据集将用于确定氮氧化物分配的当前状态，测量脱氮的程度，测量进入平流层的水蒸气分布，测量脱水，确定当前CFC 11、12和22水平以及以HCl和ClONO 2形式存在的平流层Cl，并对两个南极站点进行比较，以更深入地了解涡旋相关的化学和动力学效应。此外，收集到的数据将使光化学迁移建模者能够将模型输出与实际测量结果进行比较，特别是在中间阶段。重要的是，在这个时候，当我们接近Cl-催化臭氧破坏的恢复开始，我们有一个数据集，全面涵盖催化臭氧破坏序列和全球变暖的主要成分，以便能够正确地看待这两种机制的相对影响。

The proposed project is to develop a program of observations of atmospheric chemistry using passive infrared instruments at McMurdo and the South Pole. The measurements will be made year round for two years, and will provide significantly more and better data and constraints for photochemical transport models. Since these models are used to predict future ozone depletion and climate change, it is important that they be as accurate as possible. The Antarctic ozone hole has shown the sensitivity of the southern polar stratosphere to chlorine, and it is expected that the gradual healing of the hole to mark the success of the policy. However, model predictions indicate the possibility of a delay in recovery due to the impact of global warming on the catalytic ozone destruction process. Since most current satellite instruments do not sample the polar regions in the winter, ground based instruments can make important contributions and data from the proposed instruments would also provide validation for new satellite sensors. These instruments are the four Fourier Transform Spectrometers (FTS) operated at Arrival Heights (in collaboration with the New Zealand National Institute for Water and Air Research) and at South Pole. Two of these FTS (0.1-1.0 cm resolution atmospheric emission) will be placed at South Pole and at McMurdo for year round operation, and a 0.003 cm-1 resolution solar FTS will be deployed at South Pole to be operated during the summer. The emission instruments will provide important information during the polar night regarding HNO3 and denitrification, as well as dehydration. The transmission FTS's will provide high resolution spectra from which we will derive vertical profiles as well as vertical column amounts of many molecules important in the ozone destruction process as well as atmospheric tracers such as HF. The spectra from the emission instruments will provide year round column abundance measurements of HNO3, CH4, O3, H2O, N2O, the CFC's, ClONO2, and NO2 prior to its conversion to other odd nitrogen. The solar instruments will additionally provide some altitude profile information about those molecules, as well as HCl, ClONO2, NO, NO2, HNO3, HF, and others. The obtained spectral data set will be used to determine the current state of NOx partitioning, to measure the extent of the denitrification, to measure water vapor profiles into the stratosphere, to measure dehydration, to determine the current CFC 11, 12, and 22 levels as well as stratospheric Cl in the form of HCl and ClONO2, and to perform comparisons between the two Antarctic sites in an effort to gain more insight into vortex related chemical and dynamical effects. In addition, the collected data will provide photochemical transport modelers the ability to compare model outputs to actual measurements, especially at intermediate stages. It is important at this time when we are approaching the beginning of the recovery from Cl-catalyzed ozone destruction, that we have a data set that comprehensively covers the major constituents of both the catalytic ozone destruction sequence and global warming, so as to be able to place in perspective the relative influence of the two mechanisms.