BOSTON -- August might be the end of summer, but for about 36 million Americans suffering from ragweed allergies, it's just the start of the allergy season.

This year it will be worse than the past years, according to a recent study.

The American Academy of Allergy Asthma and Immunology said global climate change is making ragweed season worse for allergy patients, Boston television station WCVB reported.

"Increasing temperature and increasing carbon dioxide, the result of global warming, increase the ragweed pollen production up to two to four times than its normal production the previous years," said Dr. Clifford W. Bassett of Allergy and Asthma Care of New York.

"Ragweed allergy will be more severe and last longer this year," said Bassett. "I'm seeing patients that never have allergy before even in their 60s, 70s (or) 80s, or young children, became sensitized directly to ragweed pollen."

Allergy experts suggest that ragweed allergy patients check daily pollen counts in order to protect themselves from ragweed pollens.

"If you are a patient and have allergy problems and suffering, if you check the pollen count and it's very high, then you need to plan ahead," said Bassett. "You should not be outside more than eight hours without taking your allergy medication."

Allergy shots and immunotherapy are successful treatments for treating ragweed allergy patients, he said.

AAAI also suggests that patients protect themselves from direct exposure to the ragweed pollen by keeping windows closed and staying indoors when pollen counts are highest.