Allergy season, as we all know, is nothing to sneeze at. That congested, wheezy feeling can make life miserable. And for those with respiratory problems, including millions of Americans with asthma, high pollen counts can be downright dangerous.

Not only is sniffle season is getting worse, it’s lasting longer.

A recent study in the Proceedings of the National Academy of Scientists found global warming is increasing the duration of pollen seasons and making them more severe. Warmer air, along with higher levels of carbon dioxide, have created the double whammy for North American allergy sufferers.

Scientists say the warming planet has moved up the start of pollen season by 20 days since 1990. And there is 21% more pollen in the air. Researchers say the trend is accelerating.

The effects, the study says, are most pronounced in Texas, the Midwest and the Southeast. Cooler, northern climes fare a little better, including New England and the Great Lakes states.

The study examined readings from 60 pollen monitoring stations across the United States. Using satellite imagery, investigators determined that land-use changes or anomalies in tree growth hadn’t skewed pollen counts.

Allergies have a huge impact on society. Previous studies have shown they can cause students to perform poorly. Associated medical expenses cost the nation billions of dollars.

Scientists believe allergy season might make us more susceptible to respiratory viruses, including colds and flu, COVID-19 and respiratory syncytial [sin-sish-uhl] virus, or RSV.

So, keep the tissues handy and consult your doctor about possible treatment.