As the air space around them is lessened by compaction and melting, the grains become denser.

由于它们周围的空气被压缩、融化而逐渐减少，颗粒变得更加密集了。

youdao

Increases in global average air and sea temperature, ice melting and rising global sea levels all help us understand and prepare for the coming challenges.

全球空气和海洋平均温度上升、冰在融化、全球海平面上升，这一切使我们了解和准备应对即将到来的挑战。

youdao

The warmer ocean would heat the air above it, which would slow the refreezing of ice in winter, which would in turn become even more susceptible to melting in summer.

温暖的海洋将加热海洋上空的空气，这将减缓冬季冰重新冻结，这反过来使海冰更加容易在夏天融化。

youdao

When melting snow crystals or raindrops fall through very cold air, they freeze to form small particles of ice,called sleet.

VOA: special.2010.01.05

When melting snow-crystals or raindrops fall through very cold air, they freeze to form small particles of ice, called sleet.

VOA: special.2011.01.11

However, scientists do not fully understand the relationship between air and sea temperature, and the melting of ice.

BBC: Polar expedition to study Antarctica's climate history

The tsunami which followed knocked out the backup generators, leaving plant operators scrambling to keep the fuel units from overheating, melting down, and releasing radiation into the air and sea.

FORBES: Three Months Later, Japan Still in Meltdown