Rising temperatures are causing pollen seasons in North America to kick off around twenty days earlier than they used to, with pollen counts increasing by around 21 percent from 1990 to 2018.
How Much Is Climate to Blame?
Climate change, caused by humans, is thought to account for approximately 50 percent of the increase in pollen season length and 8 percent in pollen rates. With warmer weather and more carbon dioxide molecules, seasons can shift and pollen counts can be higher.
Why Is Ragweed Important?
Ragweed season has been extended at 10 out of 11 studied locations since 1995, extending by 25 days in Winnipeg, since later autumn frosts are taken into account. One ragweed plant produces up to a billion pollen grains.
How Can One Cope With It?
Longer pollen seasons increase risk of asthma and hay fever, which explains the necessity of forecasts and weather warnings. Urban parks help the population but do not negate specific effects of heat and pollution.
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