原文视听

As the Antarctic summer draws to an end,
南极的夏天接近尾声
visitors that rely on the brief
海冰重新出现
flush of food will soon
为这片海短暂的丰腴
be forced north by the return of the sea ice.
而来的拜访者 将被迫向北撤离
For the largest land predator,
对最大的陆地捕食者来说
the sea ice cannot return soon enough.
海冰的迅速出现并非好事
The end of the Arctic summer
北极的盛夏接近尾声
and the sun hasn't set for three months.
三个月以来 太阳未曾落下
It's hard to imagine the bitter cold will soon return.
难以想象的是 严寒将很快再次袭来
Some will welcome the chills of autumn,
某些动物会泰然接受秋季的萧索
but for most,
而对于大多数而言
time is running out before
被迫向南迁徙的日子
they will have to retreat to the south.
正在一步步逼近
The shorter days and colder nights trigger
越来越短的白昼和越来越冷的黑夜
a dramatic change in the willows and blueberry bushes.
让柳叶和蓝莓丛发生了奇妙的变化
They stop producing the green pigment
它们停止分泌
that harnesses the sun's energy,
吸收太阳能量的绿色素
and red and yellow pigments build up in their leaves.
红色素和黄色素染上了叶子

重点解释

time is running out before they will have to retreat to the south.被迫向南迁徙的日子正在一步步逼近

run out:用尽；耗尽；期满

The lease on our flat runs out in a few months.

我们公寓的租约还有几个月就到期了。

My passport has run out.

我的护照已失效。

retreat:撤退；改变；退避

The soldiers had to retreat when they were beaten in battle.

士兵们在战斗中受挫，不得不撤退。

You can't retreat from the responsibility in this affair.

你不能回避在这一事件中的责任。

常用短语:

retreat from (v.+prep.)
1.从…撤退move back from a position or danger

The defeated army had to retreat hastily from the field of battle.

败军被迫仓皇地从战场上撤退。

2.避开…move away from or try to get rid of sb/sth

You cannot retreat from your responsibility in this affair.

你不能回避在这一事件中的责任。

red and yellow pigments build up in their leaves.红色素和黄色素染上了叶子

build up:逐步增长；积累

The company has built up a large fund for ages.

多年来这个公司已积累了大量资金。