原文视听

The Arctic Ocean is of huge military importance,
北冰洋有重要的军事意义
as it's the shortest route between North America and Russia.
因为这里是北美和俄罗斯之间最短的通道
Since the late 1950s,
自上世纪五十年代末起
British, US and Russian submarines
英国 美国和俄罗斯的潜艇
have been patrolling the Arctic Ocean.
就在北冰洋巡逻
But as well as looking out for enemy activity,
他们在探查敌军的动向的同时
they've also been measuring the thickness of the ice,
也在测量冰面的厚度
critical when looking for a place to surface.
因为这关系到他们在何处浮出水面
When scientists got permission
当科学家获得准许
to look at the submarine crew's records,
查看潜艇船员的记录时
they discovered that the ice has been thinning fast.
他们发现冰面在急速变薄
In fact, it's nearly halved in thickness since 1980.
事实上 从1980年起已减少近一半
Across most of the Arctic Ocean,
北冰洋大部分的冰面
there are now just a couple of metres of ice.
现在只有几米厚了
It's so thin that it could
冰面实在太薄
melt away almost entirely in the summertime,
到了盛夏时节很可能会全部融化
and that includes the ice at the North Pole.
北极的冰也难以幸免
If current trends continue, then there will be
如果持续下去 在未来几十年里
open ocean here by summer's end,
到了夏末
some time within the next few decades.
这里就完全变成海洋
So, the days of the Arctic Ocean being covered
北冰洋被冰层覆盖的岁月
by a continuous sheet of ice seem to have passed.
似乎已一去不返
Whether or not that's a good or bad thing, of course,
当然 这究竟是好是坏
depends on your point of view.
每个人的观点不同

重点解释

But as well as looking out for enemy activity,他们在探查敌军的动向的同时

as well as:既 ... 又

He grows flowers as well as vegetables.

他既种菜也种花。

It's so thin that it could melt away almost entirely in the summertime,冰面实在太薄到了盛夏

时节很可能会全部融化

melt away:(使)融化, (使)消散

The crowd melted away when the storm broke.

暴风雨一来，人群就散了。

All his support melt away when he really needed it.

在他真正需要支持时，却得不到一丝半点。

Whether or not that's a good or bad thing, of course,depends on your point of view.当然这究竟是好是坏每个人的观点不同

depend on:取决于

It all depend on whether she like the boss or not.

一切都取决于她喜欢还是不喜欢这个老板。

A lot will depend on how she responds to the challenge.

在很大程度上将取决於她对这一难题的反应。