Earth and Sky:Global Warming and Ozone 全球变暖和臭氧
时间:2019-01-02 作者:英语课 分类:(科普英语)Earth and Sky
英语课
Global Warming and Ozone 1 全球变暖和臭氧
Could the coming century bring a new threat to the ozone layer? Discover one scientist's model of the effect of global warming and greenhouse gases on ozone -- on today's Earth and Sky.
DB: This is Earth and Sky.
JB: After 30 years of steady decline, Earth's ozone layer is thinner but seems to be stable. A ban on ozone-depleting CFCs is largely responsible. Computer modeling gives reason to hope for an almost full recovery of Earth's ozone layer within 60 years. But this sort of modeling is difficult -- and its predictions aren't iron-clad.
DB: And some models show the ozone layer could face a new threat -- from global warming. Drew Shindell, an atmospheric 2 scientist at NASA's Goddard Institute for Space Studies in New York City, talked with us about his computer models of climate.
Drew Shindell: So we get this combination of temperature change and methane 3 changes, water vapor 4 changes, we have changes in reactive nitrogen species -- which come from another greenhouse gas -- and all of these things put together end up leading to a net decrease in the amount of ozone in the lower stratosphere.
JB: So if the world gets warmer, stratospheric ozone might be depleted 5 again -- by 5 to 10 percent -- a return to today's low levels. What could be done then to protect the ozone layer?
Drew Shindell: Well, we would have to control greenhouse gas emissions 6 and certainly that is a much more complicated problem -- and a much bigger change in economic systems and such -- than it was to change the CFCs.
DB: Special thanks today to NASA's Earth Science Enterprise. We're Block and Byrd for Earth and Sky.
n.臭氧,新鲜空气
- The ozone layer is a protective layer around the planet Earth.臭氧层是地球的保护层。
- The capacity of ozone can adjust according of requirement.臭氧的产量可根据需要或调节。
adj.大气的,空气的;大气层的;大气所引起的
- Sea surface temperatures and atmospheric circulation are strongly coupled.海洋表面温度与大气环流是密切相关的。
- Clouds return radiant energy to the surface primarily via the atmospheric window.云主要通过大气窗区向地表辐射能量。
n.甲烷,沼气
- The blast was caused by pockets of methane gas that ignited.爆炸是由数袋甲烷气体着火引起的。
- Methane may have extraterrestrial significance.甲烷具有星际意义。
n.蒸汽,雾气
- The cold wind condenses vapor into rain.冷风使水蒸气凝结成雨。
- This new machine sometimes transpires a lot of hot vapor.这部机器有时排出大量的热气。