Because of the barrier of ice to the east, the Pacific Ocean to the west, and populated areas to the north, there may have been a greater impetus for people to move in a southerly direction.

因为东面有冰的屏障，西面是太平洋，而且北面是人口稠密的地区，所以促使人们向南迁移的动力会更大。

youdao

Added a new rank of Ice Barrier to mage trainers.

法师训练师增加一个新等级的寒冰护体。

youdao

The presence of sea ice and of permafrost helps protect Arctic barrier islands for much of the year.

海冰和冻土层的出现很多年来帮助保护了北极障壁岛。

youdao

Mr. O'CONNOR: Now the trick is--one of the many tricks is to make sure that the ice barrier that is created is at sufficient distance from the heated area so as not to counteract each other.

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Less ice results in more dangerous seas because ice acts as a barrier from ocean swells.

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So it's like the Corps of Engineers removed a coastal barrier that used to be made out of ice and the coast is no longer protected.

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