Research has found that springtime levels of pollen are arriving sooner, lasting longer, and are at higher levels than in the past. Here are six tips on managing pollen allergies this spring.

Allergy season is coming sooner and lasting longer

A new report from Climate Central looked at the number of days between the last day of a freezing temperature in January through the first day of a freeze in December and found that, on average, allergy season has increased in the United States by more than two weeks.

The Western United States saw the largest increase in allergy seasons with an average increase of nearly a month, followed by the Southeast, Northeast, Southern, and Central U.S. regions.

Experts say the extended allergy season is another way climate change can affect a person's health.

"The plants can grow earlier and they can pollinate earlier," said Kari Nadeau, chair of environmental health and a professor of climate and population studies at Harvard School of Public Health. "Allergies are just getting worse and worse."

In addition, other studies have suggested that by 2040, average pollen counts will be double what they were in 2000.

"It's a nonstop onslaught of pollen in the air and the duration the levels of pollen that we're seeing are higher than ever before," said David Stukus, a pediatric allergist and immunologist at Nationwide Children's Hospital.

So far this year, springtime has arrived nearly four weeks earlier than normal in the mid-Atlantic and Northeast regions of the United States, USA Today reports.

According to the USA National Phenology Network at the University of Arizona, which tracks the progression of spring by looking at growth rates of leaf and flowers nationwide, Arkansas, Kentucky, Maryland, New Jersey, New York, Ohio, and Texas have seen the earliest signs of spring in 40 years.

6 tips on dealing with allergy season

In light of longer and earlier allergy seasons, USA Today offers several tips on how to manage your allergies this spring.

1. Check pollen counts

The American Academy of Allergy, Asthma, and Immunology (AAAAI) recommends limiting outdoor activities on days with high pollen counts, as well as keeping your windows closed. AAAAI's National Allergy Bureau provides up-to-date pollen counts.

2. Go outside on rainy days

Moisture helps clear pollen out of the air, while dry, windy days are more likely to have lots of pollen.

3. Use high-efficiency filters

Using filters can help keep the air inside cleaner, as filters trap pollen and other allergens that can come in through forced air-conditioning or heating systems.

4. Dry laundry indoors

Pollen can cling to clothes, sheets, and towels, so make sure you dry your laundry inside.

5. Treat your symptoms early

Most allergy medications work best if you take them before pollen hits the air, and some allergists recommend treatment around two weeks before symptoms typically surface. Talk to your doctor about when you should start treatment.

6. Shower after being outside

After you come inside, it's a good idea to change your clothes and rinse the pollen off your skin and hair. (Loehrke, USA Today, 3/8; Loo, ABC News, 3/8)