Field Research on Changes in Polar Atmospheric Environment -Polar Ozone Depletion-

平流层臭氧损耗的主要原因是绿色温室效应气体导致平流层中CFCs含量增加和温度降低，极地平流层云在臭氧损耗中起重要作用。平流层的反硝化作用是控制CLOx催化臭氧消耗反应的重要过程。本研究于1990/1991年和1991/1992年在瑞典基律纳进行了NOx、臭氧和气溶胶的气球测量，并于1991年冬季在费尔班克斯的Alacka进行了平流层气溶胶的激光雷达测量。在平流层低层，NOx含量低，气溶胶含量增加。考虑到该地区的大气温度下降到硝酸三水合物的冰点温度，这表明，从1型PSC，NAT引起拉格大反硝化和相应的臭氧减少，通过激活ClOx的臭氧损失反应。然而，它们之间的数量关系尚不清楚。在1991/1992年冬季，NOx的消耗进行了测量，但没有发现有意义的臭氧消耗。皮纳图博在1991年12月中旬扩散到高降雨量。这种大规模的火山扰动可能会激活平流层的反硝化作用，从而引发臭氧损失。了解火山云的全球分布对于评估平流层臭氧变化是必要的。

Stratospheric ozone depletion is tought to be due to increase in CFCs content and decrease in stratospheric temperature caused by green house effect gases, and polar stratospheric clouds seem to play an important role in the ozone loss. Denitrification of the stratosphere through appearance of polar strotospheric clouds (PSCs) is suggested an essential process controlling CLOx catalytic ozone depletion reactions. However, detailed processes are still uncertain.In this research balloon measurement on NOx, ozone, and aerosols was made at Sweden, Kiruna in witer of 1990/1991 and 1991/1992, and Lidar measurements on stratospheric aerosols in winter of 1991 at Alacka, Fairbanks.From the balloon measurements, ozone depletion. Low content of NOx, and increase in aerosol content were identified in the lower stratosphere. Considering that the atmospheric temperature of this region decreased to the frost point temperature of nitric acid trihydrates, it is suggested that from of type-1 PSCs, NAT couses lage denitrification and consequentory ozone decreases through activation of ozone loss reaction of CLOx. However, quantitative relations between those are still unclear. In winter of 1991/1992, NOx depletion was measured but meaningful ozone depletion was not identified.The lidar measurements showed that volcanic disturbance of Mt. Pinatubo had diffused to high Latitudes by mid-December of 1991. Such large scale disturbance of volcanisum may activate denitrification of stratosphere which can trigar ozone loss. It is necessary to understand global dispresion of the volcanic cloud to assess stratospheric ozone change.