Blooming flowers and new growth on trees make spring a beautiful time of the year. But for many people, all of this new growth only brings suffering in the form of allergies. Some people claim that each year their allergies seem to get worse and worse. Well, they are likely right. Environmental experts and public health researchers are all saying the same thing: Climate change can make allergies more severe and allergy seasons longer. A study published in the March 2019 journal Lancet Planetary Health found that pollen counts in the Earth’s northern hemisphere have been increasing, along with a rise in temperatures. The lead writer of that study is Dr. Lewis Ziska, a scientist at the United States Department of Agriculture. For the past 20 years, he has been studying the effects of climate change on allergens. He told VOA Learning English that his research takes scientific theory and helps people’s health.