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MARPLOT® is a mapping program developed jointly by NOAA and the Environmental Protection Agency (EPA), and it runs on both Windows and Mac computers. Download MARPLOT from the EPA CAMEO® site.

With MARPLOT's easy-to-use GIS interface you can add your own objects (symbols, rectangles, circles, polylines, and polygons) to maps, as well as view and edit data associated with those objects. You can choose between several basemaps for the background image, and you can customize your map further with annotations and online Web Mapping Service (WMS) layers. You can also interact with the map in other ways, such as getting population estimates within an area.

As part of the CAMEO software suite, MARPLOT can be used with other programs in the suite: you can link map objects to the CAMEO Data Manager program and easily display ALOHA® threat zones. However, MARPLOT can also be run by itself as a general mapping program.

A derailed tank car location is marked with a symbol object on this sample map, and an ALOHA threat zone estimate shows where the chemical might travel downwind if the tank ruptures. The toolbar and panel surround the map, giving easy access to tools and menus.
Sample MARPLOT screenshot showing a fictional train derailment with ALOHA threat zone estimates for the chemical release.
More Information about MARPLOT
  • MARPLOT Fact Sheet [PDF, 676 KB]: Learn more about the key features in the MARPLOT program.
  • CAMEO News Service: This mailing list provides a way for the CAMEO team (at EPA and NOAA) to communicate important information to the CAMEO community. It is used primarily to send updates when new releases are available for ALOHA, CAMEO Chemicals, CAMEO Data Manager, MARPLOT, and/or Tier2 Submit. The service is hosted by NOAA. Follow this link to subscribe.

Questions: Contact us with questions, comments, or suggestions about MARPLOT.

Last updated Tuesday, December 22, 2020 10:08pm PST