雪的形成與作用。

Hints：
two and one-half centimeters
Earth's atmosphere

翻譯：龍貓08
校對(duì)：OFELIA1030
組長(zhǎng)：jushua
答疑：凌云飛雪
When snow crystals stick together, they produce snowflakes. Snowflakes come in different sizes. As many as 100 crystals may join to form a snowflake larger than two and one-half centimeters. Under some conditions, snowflakes can form that are five centimeters across. Usually, this requires near-free…
雪晶粘在一起形成了雪花。雪花的大小各有不同。100個(gè)雪晶結(jié)成一個(gè)大于2.5厘米的雪花。在某些情況下，雪花可以達(dá)到5厘米大小。通常這種情況需要接近冰點(diǎn)的溫度，微風(fēng)和地球大氣活動(dòng)變化。 雪包含的水分遠(yuǎn)低于雨水。2.5厘米大小的雨水所含的水分大約和15厘米的濕雪一樣。76厘米的干雪所含水分相當(dāng)于2.5厘米的雨水所含的水分…