The following passage is adapted from a 2008 article.

Stratospheric ozone absorbs ultraviolet solar radiation and prevents it from reaching Earth's surface and boosting skin-cancer rates. In Antarctic springtime (September to early December), stratospheric ozone concentrations are low. Consequently, the stratosphere absorbs less ultraviolet radiation and is therefore much cooler. This, in turn, increases temperature differences between air over the mid-latitude Southern Hemisphere regions and air over Antarctica—differences that cause strong, steady winds called the circumpolar westerlies.

These winds have been strengthening in recent decades due to "the ozone hole"—the low polar-ozone concentrations arising from a decades-long decline. These strengthened winds have been preventing many storm systems that head south from temperate latitudes—as well as the large quantities of warm air they contain—from reaching central Antarctica. Recently, however, average Antarctic stratospheric ozone concentrations have been increasing. Research indicates that this recovery of the ozone layer, if sustained, would slow the circumpolar westerlies while strengthening other southern-hemisphere winds, a combination that would significantly shift weather patterns. Much of Australia would become drier, and portions of South America wetter. Moreover, if control of ozone-depleting substances brings about a full recovery of the Antarctic ozone layer, the average air temperature in Antarctica may be significantly higher.


The passage indicates that ozone in the stratosphere over Antarctica


absorbs ultraviolet radiation more readily than does any other chemical substance in Earth's atmosphere

is fairly evenly redistributed by the circumpolar westerlies

is more abundant at higher altitudes than at lower

chemically interacts with gases emitted by industrial activities

is not equally abundant in all seasons of the year

考题讲解
还没有题目讲解(毕出老师会陆续发布对官方考题的解读,请保持关注)。

登录注册 后可以参加讨论

快来第一个发言吧
BiChu21-RC