Limited access to supermarkets, grocery stores, or other sources of healthy and affordable food can make it harder for some Americans to eat a healthy diet, and food access may be impacted by rising temperatures, changing weather patterns, and increases in the frequency of extreme events. The Food Access Research Atlas from the U.S. Department of Agriculture's Economic Research Service lets users view maps that show food access indicators by census tract (census tracts are subdivisions of counties for which the U.S. Census Bureau collects statistical data). The Atlas also provides this data in downloadable formats. These maps and data can help planners identify populations vulnerable to food access issues.

Indicators available for mapping include distance to the nearest supermarket, whether or not a census tract is considered low-income, vehicle availability, and frequency of people living in "group quarters" (to help distinguish institutional settings, such as military facilities or college campuses, that technically meet the low-access and low-income conditions, but are likely to provide regular dining services). Users can also view indicators of food access for selected subpopulations and can download census tract-level data on food access measures.