His fall would slow at lower altitudes amid increasing wind resistance .

海拔较低时，他的速度会因为不断增强的风的阻力作用而减慢。

Grey indicates high clouds , and brown indicates clouds at intermediate altitudes

灰色表示高空云层，而褐色则表示中海拔云层。

There are currents of wind at different altitudes .

不同的高度都有气流。

Studying sediments from cliff sections along the river delta , he said the evidence spanned a large area at many altitudes .

通过研究麦肯色尔三角洲沿岸陡剖面的沉积物，他说发现的证据包括了一个跨越很多海拔高度的大面积区域。

Some light aircraft and gliders operating at low altitudes in clear weather are not required to have even radios , let alone transponders or radar .

一些在晴好天气在低海拔飞行的轻型飞机和滑翔机甚至都不需要配备无线电，更不用说转调器或者雷达了。