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 how the length of ragweed pollen season changed at 11 locations in the central United States and Canada between 1995 and 2015 based on Ziska et al. 2016. Orange-brown circles represent a longer pollen season; the green circle represents a shorter season. 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).