Mass migrations have happened throughout history.

历史上曾发生过大规模人口流动。

It's one of nature's most spectacular mass migrations.

黑脉金斑蝶的迁徙是自然界最壮观的大规模迁徙之一。

From climate change, mass migration, pandemics, job loss and now war.

气候变化，大规模移民，疫情，失业，现在又有了战争。

Traditionally the holiday marks the largest mass migration of humans each year.

往常来说，这个节日标志着每年最大规模的人口迁移。

The result was a mass migration of the herbivores that consumed them.

其结果就是以它们为食的植食动物大规模迁徙。

Mass migration brought new diseases that indigenous creatures had no resistance to.

大规模迁徙带来了当地生物无法抵抗的新疾病。

But Earth's biggest mass migration actually happens every single night and it's underwater.

但是地球上最大的大规模迁徙实际上每天晚上都在发生，而且是在水下。

Is that too much to ask to stabilize the world against famine, destabilization and mass migration?

为了世界稳定，防止饥荒、动荡和大规模移民，这样的要求过分吗？

Even the gloomiest estimate might prove too rosy if climate change triggers conflicts or mass migrations.

如果气候变化引发冲突或大规模移民，那即便最悲观的预测也可能变得过于乐观。

For if not, a mass migration could occur, unlike the likes we have ever before seen.

因为如果不这样做，就可能发生大规模的移民，其规模之大会是我们以前从未见过的场景。

Not long ago it seemed as if many wealthy countries had turned decisively against mass migration.

就在不久前，许多富裕国家似乎还坚决反对大规模移民。

Everyone must use less water if famine, pestilence and mass migration are not to sweep the globe.

如果我们不想让饥荒、瘟疫以及人类大规模迁徙横扫全球，就必须人人节约用水。

The mass migration is partly the result of people fleeing severe economic and political problems in Venezuela.

大规模移民的部分原因是人们逃离委内瑞拉严重的经济和政治问题。

Greenhouse gas emissions keep going up. We're losing the Arctic. We anticipate food crises, mass migration, internal migration.

温室气体持续上升，北极正在消失，我们或迎来粮食危机，大量移民和国内迁徙。

The Pew report said this is a turning point in one of the largest mass migrations in US history.

皮尤研究表明，美国历史上规模最大的移民潮正在发生转变。

Fauton says a weak global economy in the 1970s triggered in part the mass migration of Haitians to the US.

福顿说，20世纪70年代全球经济疲软在一定程度上引发了海地人向美国的大规模移民。

Mass migration happened as people tried to escape food shortages.

当人们试图摆脱食物短缺时， 大规模移民就发生了。

This started the largest forced mass migration in human history.

这开始了人类历史上最大规模的被迫大规模移民。

El Salvador and Guatemala to put an end to the mass migrations.

萨尔瓦多和危地马拉结束大规模移民。

With storms and droughts and mass migration still just stuck in conversation.

风暴和干旱以及大规模移民仍然停留在谈话中。