Shared Enterprise Geodata and Services (SEGS) provides an EPA-curated collection of recommended geodata assets that are nationally relevant and support the Agency’s mission to protect human health and the environment. By connecting EPA users with curated datasets and promoting service reuse, SEGS aims to enhance information access, reduce data-storage costs, and improve the consistency and quality of data at the US EPA.

Developed by the U.S. EPA Office of Air and Radiation, this content item depicts the total change in last spring frost date 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 first 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).