SSS 2008-08-25
时间：2018-12-24 作者：英语课 分类：Scientific American(八)月
This is Scientific American's 60-Second Science. I'm Steve Mirsky . Got a minute?
For accurate weather forecasting and climate analysis, researchers need the best models possible about how the air circulates above the earth. And a new study is challenging the conventional picture of the planet’s air movements. Previous theories pointed 1 to two large circular systems—air rises at the warm equator and then travels toward either pole, where it chills and falls. But the new study posits 2 that there are actually four distinct air masses, two north of the equator and two south. The work appears in the August 21st issue of the journal Science.
In this new view, air again rises at the equator, but falls in the subtropics, making the first cell. The second cell consists of air rising in the middle latitudes—about 30 to 60 degrees north and south—and then falling again near the poles. The study says that this second cell of rising air accounts for temperatures, winds and moisture levels in the mid-latitudes. Water vapor 3 is a major driver of weather events in the tropics. Turns out it may be just as important for weather—and climate—farther north and south.
Thanks for the minute for Scientific American's 60-Second Science. I'm Steve Mirsky.
- He gave me a very sharp pointed pencil.他给我一支削得非常尖的铅笔。
- She wished to show Mrs.John Dashwood by this pointed invitation to her brother.她想通过对达茨伍德夫人提出直截了当的邀请向她的哥哥表示出来。
- If a book is hard going, it ought to be good. If it posits a complex moral situation, it ought to be even better. 如果一本书很难读，那么它应该是一本好书；如果它提出了一个复杂的道德状况，那么它就更应该是本好书了。 来自《简明英汉词典》
- Ray posits that this miracle is an object lesson for the disciples. 雷把这个奇事当作教训信徒们的事件。 来自互联网