High thin clouds are very transparent to solar radiation, like clear air.

太阳辐射可以轻易地通过高空薄云层，就像通过空气一样。

youdao

It seemed to hold the moonlight in suspension, rendering it more pervasive than in clear air.

那层雾似乎使月光悬浮起来，让那层雾比在晴朗的天气里显得更具有弥漫性。

youdao

They need to be certain of several hours of clear air as it will take two hours for an initial reconnaissance team to reach the area where the missing men are.

搜救人员需要确定干净的空气能保持数小时，因为打头阵的侦察队确定被困矿工的位置就需要两个小时。

youdao

"Our study showed for the first time a clear difference between oxygen and air in the treatment of acute cluster headache.

VOA: standard.2009.12.17

He said a lot of misinformation is being spread by critics of reform, adding that it is necessary to clear the air.

VOA: standard.2009.08.11

"Twenty percent of attacks were improved on placebo,which is air, and 78 percent of attacks were improved on oxygen, a clear difference in favor of oxygen,"

VOA: standard.2009.12.17

On the count of three, he said, we would just roll out into the cold, clear air.

WSJ: Sky-Diving in New Zealand

Kaiser believes, however, that the terminology in the public debate on clear air standards will have to change to accomplish these goals.

FORBES: Billionaire George Kaiser Has A Big Green Energy Plan

They found that gravity waves "break" on the surfaces of planes, just like ocean waves breaking on the beach, causing much of the turbulence that occurs out of the blue in clear air.

MSN: Blame gravity waves for turbulence - Technology & science - Science - LiveScience | NBC News