科学美国人60秒 SSS Biggest Rivers Are Overhead
时间：2019-01-20 作者：英语课 分类：2017年Scientific American(三)月
Back in January, one of California's oldest and most iconic residents keeled over: the Pioneer Cabin tree, a giant sequoia 2 in Calaveras Big Trees State Park…so big you used to be able to drive through it.
The giant was blown over by high winds—delivered by what’s called an atmospheric 3 river, a long stream of water vapor 4 in the atmosphere, 100 miles wide. These systems might be thought of as some of the biggest rivers on Earth.
"You could kind of pose it that way, yeah." Duane Waliser (WALL-i-ser), an atmospheric scientist at the Jet Propulsion Lab. "An atmospheric river will carry the same amount of water vapor as, say, 15 to 20 Mississippi Rivers."
Waliser and his JPL colleague Bin 1 Guan developed an algorithm to detect atmospheric rivers in historical data, so they could connect the sky flow to extreme events on land. And they found that, if you look at just the top 2 percent most extreme wind- and rain- and snow-storms in the world's midlatitude regions—atmospheric rivers are linked to up to half of them.
And of the 19 windstorms in Europe that cost insurance companies the most money—billions of dollars in damage—atmospheric rivers were behind three-quarters of those events. The study is in the journal Nature Geoscience. [Duane Waliser and Bin Guan, Extreme winds and precipitation during landfall of atmospheric rivers]
Looking ahead, as global temperatures rise, that warmer air holds more water vapor. "And so the tendency looks like, if the climate does warm, you would tend to have stronger or more frequent atmospheric rivers." And as this study shows: it won't just be that a hard rain's gonna fall. We'll be blowing in the wind, too.
—Christopher Intagliata
- He emptied several bags of rice into a bin.他把几袋米倒进大箱里。
- He threw the empty bottles in the bin.他把空瓶子扔进垃圾箱。
- The sequoia national forest is at the southern end of the sierra nevada range.红杉国家公园位于内华达山脉南端尽头处。
- The photo shows the enormous general Sherman tree in California's sequoia national park.照片显示的是加利福尼亚州红杉国家公园内巨大的谢尔曼将军树。
- 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。