Allergies: Expert shares how long winter, climate change may affect symptoms this season

The warm weather has finally arrived for much of the country, but it's bringing an extra dose of pollen for allergy sufferers this year as a result of the long winter and climate change, according to CBS News medical contributor Dr. Holly Phillips.

The extremely cold winter, she explained on "CBS This Morning," is helping packing a particular allergy punch this year because plants' growth is not staggered.

"What usually happens is spring brings our tree pollen. Summer brings our grass pollen and then in the fall we see ragweed," she said. "Because our spring was so delayed this year, many things are blooming up all at once. What should have bloomed over a course of a month is now popping up altogether, so we're seeing really, really high pollen levels."

As for an increase in carbon dioxide levels, often associated with the effects of climate change, Phillips said they can "supercharge" some plants' growth, such as ragweed, a common irritant for allergy sufferers.

"More carbon dioxide makes them grow faster, more robustly and makes them release more pollen," she said. "So that's one of the ways we're seeing the climate change the type of allergens that are in the air. People who didn't have allergies in one area might now."

In order to combat allergies this season, Phillips recommends people attempt to keep allergens out of the home with tactics such as shower upon re-entering the home and immediately taking off outer garments. Additionally, she recommended allergy sufferers avoid early morning outdoor activity, use an air-conditioner, explore new medicinal options and avoid stress and anxiety.