Turns out that those who think every allergy season is the worst one ever may actually be right, as explained in CNN.com's Why your allergies are bugging you.

The reason for worsening allergy seasons is two-fold: There's more pollen and it's sticking around for longer. As Estelle Levetin, Ph.D., chairwoman of the aerobiology committee for the American Academy of Allergy, Asthma & Immunology puts it: "Pollen levels are increasing, pollen seasons are getting longer, and more people are developing allergies."

This year's fall allergies are estimated to last up to 27 days longer than average in some parts of the country.

Here is a summary of the reasons behind these more potent and longer-lasting allergy seasons, which occur both in the spring and the fall:

• "Spring allergies now start sooner and fall allergies end later, thanks to global warming," says Jeffrey G. Demain, M.D., director of the Allergy, Asthma & Immunology Center of Alaska.


• Carbon-based fuels trap heat over the earth's surface, causing temperatures to rise. This heat prompts an early spring, and delays the first frost – making both seasons longer.


• Increased temperature also heighten the allergenic property of each pollen grain. "There's more allergen now in each grain than there used to be," Demain says.


• Higher temperatures also contribute to more prolific mold, another fall allergy trigger.