Infrared Measurements of Atmospheric Composition over Antarctica

拟议的项目是开发一个在麦克默多和南极使用被动红外仪器进行大气化学观测的方案。这些测量将在两年内全年进行，并将为光化学传输模型提供明显更多和更好的数据和约束。由于这些模型被用来预测未来的臭氧消耗和气候变化，因此它们尽可能准确是很重要的。南极臭氧层空洞已经显示出南极平流层对氯的敏感性，预计空洞的逐步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进程的影响，复苏可能会延迟。由于目前的大多数卫星仪器不在冬季对极地地区进行采样，地面仪器可以做出重要贡献，来自拟议仪器的数据也将为新的卫星传感器提供验证。这些仪器是在到达高地(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(FTS)。其中两个FTS(分辨率为0.11.0厘米的大气排放)将放置在南极和麦克默多进行全年运行，并将在南极部署一个0.003厘米-1分辨率的太阳FTS，以便在夏季运行。排放仪器将在极夜期间提供有关硝酸和反硝化以及脱水的重要信息。传输FTS将提供高分辨率光谱，我们将从中得出许多在臭氧破坏过程中非常重要的分子的垂直剖面和垂直柱数量，以及大气示踪剂，如HF。发射仪器的光谱将提供HNO_3、CH_4、O_3、H_2O、N_2O、氟氯化碳、ClONO2和NO2在转化为其他奇数氮之前的全年柱丰度测量。太阳仪器还将提供一些关于这些分子以及HCl、ClONO2、NO、NO2、HNO3、HF等的海拔分布信息。获得的光谱数据集将用于确定NOx分配的当前状态，测量反硝化程度，测量进入平流层的水蒸气轮廓，测量脱水，确定目前的CFC11、12和22水平以及平流层氯以HCl和ClONO2的形式，并在两个南极地点之间进行比较，以努力更深入地了解与涡旋有关的化学和动力学影响。此外，收集的数据将使光化学传输模型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，在我们即将开始从氯催化的臭氧破坏中恢复的时候，我们必须有一个全面涵盖催化臭氧破坏顺序和全球变暖的主要组成部分的数据集，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.