极地平流层云及其非均相化学

Polar Stratospheric Clouds and Its Heterogeneous Chemistry

南极臭氧洞的形成与南极平流层云及其非均相化学过程有很大关系。南极平流层云中存在着硫酸气溶胶粒子、与硫酸 硝酸 水有关的固体或液体粒子以及水的冰晶粒子等 ,在其表面上可以发生非均相化学反应 ,一方面使本来比较惰性的硝酸氯 (ClONO2 )具有相当大的活性 ,另一方面可以把NO2 或硝酸以硝酸固体粒子的形式从平流层中移走。由非均相化学产生的HOCl和Cl2 发生光离解 ,产生活性氯 ,加强了与ClO的二聚物或者与ClO BrO互反应有关的破坏臭氧的催化循环圈的进行 ,加快南极臭氧洞的形成。本文重点介绍极地平流层云及其非均相化学在极地平流层臭氧消耗过程中的作用 。

The formation of Antarctic ozone hole is mainly related to the polar stratospheric clouds and the processes of heterogeneous chemistry. In Antarctic polar stratospheric clouds, there are sulfuric acid aerosols, some solid and liquid particles related to HNO 3/H 2SO 4/H 2O, and ice crystals of water. The heterogeneous chemical reactions will occur on the surface of polar stratospheric clouds particles. On one hand, they make ClONO 2 to react with some molecules to release Cl 2 and HOCl, both of which in turn release Cl atoms that destroy ozone. On the other hand, they convert stratospheric nitrogen compounds (N 2O 5, NO and NO 2 ) to HNO 3, which will be removed out from stratosphere in the way of solid particles. The catalytic cycles of ClO dimmer, and co reaction of ClO BrO will be enhanced by the release of Cl atoms, and which will promote the formation of Antarctic ozone hole. The emphases of this paper will be placed on introducing effects of polar stratospheric clouds and its heterogeneous chemistry on the ozone depletion process in polar stratosphere, and make a clear understanding of heterogeneous chemistry occurred on surface of polar stratospheric clouds.