Climate change could make pollen rise and allergies worse

Perhaps you’ve heard the argument that a rise in carbon dioxide levels is a good thing, because CO2 helps plants grow. Well, says Hah-vard’s Paul Epstein, “It is the opportunistic plants like poison ivy and ragweed that thrive.” That’s right, ye allergy-stricken: More CO2 means more pollen, according to a new study. Harvard researchers found that ragweed grown under conditions mimicking a warming globe produced about 55 percent more pollen than ragweed grown under current conditions. Climate change is already causing spring to arrive earlier in many places, but researchers wrote, “In future climates with elevated [CO2], we predict pollen production will be just as robust in years with late springs as in years with early springs.” Super. Early spring does seem to have a side effect for wildlife, though: Italian scientists said yesterday that a variety of animals are coming out of hibernation early, causing them to stress out and lose weight. Good ol’ global warming. Is there anything it can’t do?