Scientists studied fungal spores in the air across the United States from 2003 to 2022 and found that spore seasons are starting earlier due to climate change, particularly from warmer temperatures. These airborne fungal spores can trigger allergies and asthma symptoms in sensitive people. The research shows the amount of spores in the air is decreasing, but they arrive sooner in the year, which has important implications for managing allergies and public health.