Special Report

27 Effects of Climate Change That Can't Be Stopped

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17. Allergy season has lengthened

Pollen season in the United States started three days earlier on average between 2001 and 2010 compared to the 1990s.

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18. More heat waves

The total global land area that has 30 days of extreme heat per year has roughly doubled since 1998.

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19. Increasing drought

If the increase in global average surface temperature reaches the 1.5°C mark, which it is almost certain to do, 350 million additional people will be exposed to severe drought regularly.

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20. More global precipitation

More water vapor in the atmosphere as a result of global warming has led to an 8.5% increase in annual daily precipitation worldwide since 1900.

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21. More precipitation in the US

Annual precipitation in the United States has increased by approximately 4% between 1901 and 2015.