Chemistry of tropospheric ozone over the tropical Pacific

对流层臭氧（O_3）是重要的温室气体之一。这一事实在大气辐射研究领域是一个常识，但最近在大气环境科学中重新得到关注。大气臭氧在控制许多反应方面也起着重要作用。例如，紫外线辐射对臭氧的光解作用导致OH的产生，OH清除了许多重要的微量气体，包括ch_4、HCFCs（氢氯氟烃）和CO.NASA进行了飞机任务PEM-Tropics，其目的是研究热带和南半球太平洋对流层化学。使用两种飞行器测量活性氮和其他前体物质。1996年9月和10月在南美洲西海岸和夏威夷和新西兰附近的太平洋中部进行了观测。飞机测量成功，数据正在处理中。最终的数据将被存档在NASA的数据库中。由于沃克环流，南美地区的空气在此期间下降。在对流层上层观测到的低水平的H_2O和高水平的O_3与这种输送相一致。在这个项目中，我们与密歇根大学的科学家进行了合作。在不久的将来，将利用现有的存档数据进行系统的分析。我们于1996年8月对印度尼西亚进行了实地访问，以便为计划于1997-1999年进行的飞机任务做准备。讨论了在飞机观测期间与LAPAN在地面测量方面的合作。我们还邀请了新西兰国家水与大气研究所（NIWA）的一位科学家来讨论气溶胶测量的技术细节。

Tropospheric ozone (O_3) is one of the important greenhouse gases. This fact was a common knowledge in the research field of atmospheric radiation, but it has been recently re-focused in the atmospheric environmental science. Atmospheric ozone also plays an important role in controlling a number of reactions. For example, photolysis of ozone by ultraviolet radiation leads to the production of OH,which scavenges many important trace gases including CH _4, HCFCs (hydrochlorofluorocarbons) and CO.NASA conducted the aircraft mission PEM-Tropics, which was aimed to study tropospheric chemistry over tropical and southern hemispheric Pacific Ocean. Two kinds of aircraft were operated to measure reactive nitrogen and other precursor species. Observations were made over the west coast of south America and over the central Pacific near Hawaii and New Zealand in September and October, 1996. Aircraft measurements were made successfully and the data is being processed. The finalized data will be archived in the NASA data base. Air descends over south American region during this period due to Walker circulation. Low levels of H_2O and high levels of O_3 observed in the upper troposphere is consistent with this transport. We made cooperated efforts with scientists of University of Michigan for this program. Systematic analyzes are to be made using the Archived data available in near future.We made site visit to Indonesia in August 1996 in order to prepare for the aircraft mission planned in 1997-1999. Cooperation with LAPAN on ground based measurements during aircraft observations was discussed. Also we invited a scientist from National Institute of Water and Atmosphere (NIWA) of New Zealand to discuss aerosol measurements inn technical detail.