The gas would have the dual effect of choking air-breathing animals and preventing sunlight from reaching Earth's surface.

这些有毒气体不仅会使动物造成了窒息，而且对照射到地球表面的阳光产生了严重阻挡。

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One should also note that 2010 saw a spike in mortality over the summer months when most of central Russia was choking on peat smoke, so some of the mortality improvement in 2011 is because of the base effect.

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