SSS 2009-06-15
时间:2019-01-08 作者:英语课 分类:Scientific American(六)月
This is Scientific American's 60-second Science. I'm Steve Mirsky. Got a minute?
Could it be that our understanding of rain was all wet? A new study says that some drops of rain are falling faster than they should be. Which ultimately means that it may be raining less than we think.
It’s been assumed that large raindrops fall faster than smaller ones. A big drop’s size and heft give it a faster terminal velocity 1. Because it overcomes air resistance better than a small drop. But now researchers have found small raindrops falling faster than some bigger drops, and faster than what their terminal velocity should be. The finding appears in the journal Geophysical Research Letters.
Researchers used sophisticated optical equipment to study about 64,000 individual raindrops, and found the expeditious 2 outliers. Which came in clusters. These superfast droplets 3 probably come from the breakup of fast-moving large drops. Standard techniques to measure rain assume that fast drops are larger, and therefore overestimate 4 the total precipitation. The scientists note that a third of the economy is influenced by weather forecasting, so even a small improvement in our understanding of rain would be more than a drop in the bucket.
Thanks for the minute for Scientific American's 60-second Science. I'm Steve Mirsky.
- Einstein's theory links energy with mass and velocity of light.爱因斯坦的理论把能量同质量和光速联系起来。
- The velocity of light is about 300000 kilometres per second.光速约为每秒300000公里。
- They are almost as expeditious and effectual as Aladdin's lamp.他们几乎像如意神灯那么迅速有效。
- It is more convenien,expeditious and economical than telephone or telegram.它比电话或电报更方便、迅速和经济。
- Droplets of sweat were welling up on his forehead. 他额头上冒出了滴滴汗珠。 来自辞典例句
- In constrast, exhaled smoke contains relatively large water droplets and appears white. 相反,从人嘴里呼出的烟则包含相当大的水滴,所以呈白色。 来自辞典例句
- Don't overestimate seriousness of the problem.别把问题看重了。
- We overestimate our influence and our nuisance value.我们过高地估计了自己的影响力和破坏作用。