Satellite Observations of Halogen-Containing Molecules

高层大气中的臭氧消耗主要是由人为释放氯氟化碳（CFCs）等氯化分子造成的。这种对臭氧层的破坏增加了到达地面的有害紫外线辐射量。由于《蒙特利尔议定书》，寿命长的氟氯化碳正在被寿命较短的含氢物质（氢氯氟烃，HCFC）和不含氯的分子（氢氟碳化合物，HFC）所取代。预计《蒙特利尔议定书》的成功将在本世纪中期结束对臭氧的破坏。为了核查遵守情况和监测进展情况，需要测量这些物种的浓度随时间、地点和高度的变化。臭氧破坏发生在高层大气中，因此需要测量那里的氯和氟预算。我们建议使用大气化学实验傅里叶变换光谱仪（ACE-FTS）测量主要的氟和氯气体（包括有机源气体和无机产物气体）的全球分布。ACE卫星从2004年至今一直在提供高质量的数据，因此可以根据高度和纬度得出趋势。含氟和氯的有机物是强大的温室气体。事实上，在二氧化碳和甲烷之后，这组气体是气候变化的第三大驱动因素。《蒙特利尔议定书》的成功带来了无意中的气候惠益，尽管替代氢氟碳化合物的迅速增加令人担忧。我们建议确定这些物种中许多物种的寿命，我们的全球分布将导致全球变暖潜力和辐射强迫的估计，量化它们在引起气候变化方面的有效性。气候变化和高层大气臭氧消耗是大气科学中最重要的两个问题。我们的提案将为世界气象组织2014年臭氧消耗科学评估和目前正在编写的政府间气候变化专门委员会2013/2014年第五次评估报告做出重要贡献。

Ozone depletion in the upper atmosphere is caused mainly by the anthropogenic release of chlorinated molecules such as chlorofluorocarbons (CFCs). This damage to the ozone layer increases the amount of deleterious ultraviolet radiation that reaches the ground. As a result of the Montreal Protocol long-lived CFCs are being replaced by shorter-lived species that contain hydrogen (hydrochlorofluorocarbons, HCFCs) and molecules without chlorine (hydrofluorocarbons, HFCs). It is anticipated that the success of the Montreal Protocol will end ozone destruction by the middle of this century. In order to verify compliance and monitor progress, the concentrations of these species need to be measured as function of time, location and altitude. Ozone destruction takes place in the upper atmosphere so measurements of chlorine and fluorine budgets are needed there. We propose to measure the global distributions of the main fluorine- and chlorine-containing gases (both organic source gases and inorganic product gases) with the Atmospheric Chemistry Experiment Fourier Transform Spectrometer (ACE-FTS). The ACE satellite has been providing high quality data from 2004 to the present so trends can be derived as a function of altitude and latitude. Organic fluorine- and chlorine-containing species are powerful greenhouse gases. In fact, after carbon dioxide and methane, this group of gases are the third most important drivers of climate change. The success of the Montreal Protocol has lead to an inadvertent climate benefit, although the rapid increase in replacement HFCs is cause for concern. We propose to determine improved lifetimes for many of these species, and our global distributions will lead to improved estimates of global warming potentials and radiative forcings that quantify their effectiveness in causing climate change.Climate change and ozone depletion in the upper atmosphere are two of the most important problems in atmospheric science. Our proposal will make important contributions to the World Meteorological Organization's 2014 Scientific Assessment of Ozone Depletion and the Fifth Assessment Report of the Intergovernmental Panel on Climate Change that is now under way for 2013/2014.