Even relatively small impacts can do a lot of damage .

即使是相对较小的冲击也能带来巨大的破坏。

Those impacts occur every 30000 years , on average .

这类撞击平均每3万年发生一次。

This idea might even explain why evolution appears to speed up after environmental catastrophes such as asteroid impacts .

这种想法甚至可以解释为什么在发生小行星碰撞这样的环境灾难之后，进化似乎在加快。

In particular , it must provide comprehensive support to those who bear the heaviest climate impacts .

特别是，它必须向那些遭受最严重气候冲击的国家提供支持。

Without co-ordinated international action on greenhouse gas emissions , the impacts on climate and civilisation could be severe .

如果不采取协调的国际行动减少温室气体排放，那么气候和文明都将经受严重冲击。