Developed by the U.S. EPA Office of Air and Radiation, this content item depicts the total change in length of the growing season from 1895 to 2020 for each of the contiguous 48 states. For this indicator, the length of the growing season is defined as the period of time between the last frost of spring and the first frost of fall, when the air temperature drops below the freezing point of 32°F. Data were provided by Dr. Kenneth Kunkel of NOAA's Cooperative Institute for Climate and Satellites (Kunkel et al. 2004; 2016 Update). For more information, please visit the U.S. EPA climate change indicators webpage. These data and their corresponding metadata records can be downloaded from the EPA Environmental Dataset Gateway (EDG).