What is a geographic information system?

GIS is a computer system that captures, stores, checks, and displays information related to positions on Earth’s surface.

The ability to link maps digitally to information enables us to visualize and understand patterns and relationships around us. Geographic information systems, or GIS, provides this link. For example, this sea level rise planning map uses GIS to show what the future 100-year floodplain boundaries could look like in the New York area when accounting for sea level rise. Move your mouse (or finger) back and forth over each image to view the "before and after" comparison.

GIS is a computer system that captures, stores, checks, and displays information related to positions on Earth’s surface. It helps analysts and scientists study climate change, land use planning, business, and even our nation’s defense. You might use it to find the closest restaurant or book store using your phone’s GPS. At NOAA, GIS is used to map oil spill trajectories and historic hurricane tracks, view and analyze nautical charts, and understand trends in areas such as sea level change and coastal socioeconomics.

Explore some of the GIS-related products and services NOAA provides to:

  • Build strong, more resilient coastal communities:

    Sea Level Rise and Coastal Flooding Impacts Viewer

    Using the best available science and data, federal agencies developed a sea level rise planning tool to help state and local officials, community planners, and infrastructure managers understand possible future flood risks from sea level rise for use in planning decisions. This, and many other coastal GIS tools are available from NOAA's Digital Coast.
  • Prepare for and recover from environmental and natural disasters:

    Environmental Response Management Application (ERMA®)

    ERMA is an online mapping tool that integrates both static and real-time data, such as ship locations, weather, and ocean currents, in a centralized, interactive map for environmental disaster response. Having the latest information in an easy-to-use format provides managers with the data they need to make informed decisions.
  • Protect habitat for fisheries and marine life:

    NOAA's Habitat Blueprint

    In support of NOAA's Habitat Blueprint Project, a web-based GIS tool for online collaboration was developed. The tool provides stakeholders Web map access to areas in California that could be used to demonstrate the "habitat blueprint"—a framework to improve habitat for fisheries, marine life, and coastal communities.
  • Make navigational charts available as a planning tool to GIS users and coastal planners:

    Seamless Raster Navigational Charts & Web Mapping Services

    NOAA's Raster Navigational Charts are designed for marine navigation, but can also be used as a marine base map by GIS users, coastal and ocean planning staff, and the public. This service contains 2,100+ charts displayed as a seamless mosiac with updates provided monthly.
  • Improve data and location precision:

    Continuously Operating Reference Stations (CORS)

    Surveyors, GIS users, engineers, scientists, and the public that collect GPS data can use CORS data to improve the precision of their positions. The network of 1,800 CORS stations improves coordinates relative to the National Spatial Reference System, both horizontally and vertically.