Climate Facts

Plants love carbon dioxide (CO₂) and many thrive with higher concentrations of this heat-trapping gas in the atmosphere. Unfortunately, this fact is true for both desirable plants, like food crops, and undesirable ones, like ragweed and poison ivy.

Researchers have found that poison ivy plants, for example, grow faster and produce more toxic oil per plant in high-CO₂ environments. Poison ivy toxicity could double later this century if CO₂ emissions continue unabated. Ragweed has also been shown to grow faster, with increased pollen production and more allergenic pollen, when grown in warmer conditions with higher levels of CO₂. Tree and grass pollen, both common allergens, have similar responses. 

With more than 50 million Americans suffering from seasonal allergies, at a cost of $18 billion annually, a more severe and intense allergy season will reduce the health and well-being of many Hoosiers.
 

Additional information, including research references to the above statements, are available in the IN CCIA Report Hoosiers' Health in a Changing Climate.