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 shows trends in unusually cold temperatures at individual weather stations that have operated consistently since 1948 based on NOAA 2021. In this case, the term “unusually cold” refers to a daily minimum temperature that is colder than the 5th percentile temperature during the 1948–2020 period. Thus, the minimum temperature on a particular day at a particular station would be considered “unusually cold” if it falls within the coldest 5 percent of measurements at that station during the 1948–2020 period. The map shows changes in the total number of days per year that were colder than the 5th percentile. Blue upward-pointing symbols show where these unusually cold days are becoming more common. Orange downward-pointing symbols show where unusually cold days are becoming less common. 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).