Geography

U.S. Census Cartographic Boundary Files are simplified versions of the Census TIGER/Line boundary files, designed specifically for making maps. Whereas TIGER/Line files are highly detailed and precise for very complex, large files that can be slow to render and visually “busy” on a map, Cartographic Boundary Files are smoothed and generalized with small details removed, jagged edges smoothed out, and coastal boundaries clipped to the shoreline. This makes them smaller in file size, faster to render, cleaner, and more visually appealing on a map.

TIGER (Topologically Integrated Geographic Encoding and Referencing )/Line files are the Census Bureau’s comprehensive database of geographic features across the entire United States, stored as vector GIS files. They contain two broad categories of features:

1. Administrative and statistical boundaries — states, counties, census tracts, voting districts, school districts, ZIP codes, and dozens of other boundary types.
2. Physical and cultural features — roads, highways, railroads, rivers, streams, lakes, coastlines, and landmarks.

The U.S. Census Geography Program is the geographic framework and production program behind geographic datasets published by the U.S. Census Bureau. Its primary data source is the TIGER (Topologically Integrated Geographic Encoding and Referencing) database, from which numerous products are derived. It provides access to  boundaries, linear features, points, geographic codes, and crosswalk files.

The National Map is USGS’s main portal for topographic, elevation, hydrography, and land cover data. It provides access to base geospatial information representing the topography, natural landscape, and built environment of the United States and its territories. The National Map supports digital and print versions of topographic maps, data downloads, web map services, and online viewing of maps and data.

EnviroAtlas is a web-based environmental mapping and data platform developed by the United States Environmental Protection Agency that provides geospatial data, interactive tools, and resources that allow users to explore how ecosystems support human health and well-being. It provides access to more than 500 maps and analytical tools centered on ecosystem services, biodiversity, and human health.

NOAA GeoPlatform is a cloud-based GIS portal that provides geospatial data, maps, and analytics in support of the National Oceanic and Atmospheric Administration’s mission. It brings together information from across NOAA and makes it available through interactive maps, downloadable layers, and analytical tools to support research, resource management, and decision-making.

The NOAA Office for Coastal Management (OCM) helps communities protect and manage the United States coastal and Great Lakes regions. It provides a wide range of geographic and geospatial data focused on the coastal United States and Great Lakes regions. Most of these datasets are available through Digital Coast and the Data Access Viewer.

NOAA Data includes environmental observations of the Earth’s oceans, atmosphere, space weather, and ecosystems. The page serves as the central gateway to all of NOAA’s data holdings, organized into the following major data categories:

EarthExplorer (EE) is an online search, discovery, and ordering tool developed by the USGS. It supports the searching of satellite, aircraft, and other remote sensing inventories. It is operated by the USGS Earth Resources Observation and Science (EROS) Center, which maintains one of the largest civilian collections of images of the Earth’s land surface.

Earthdata is a data system managed by the National Aeronautics and Space Administration (NASA) that provides access to a massive collection of Earth science data collected by NASA satellites, aircraft, and field missions. Provide a concise, but easy-to-understand description of Earthdata.It provides the largest collection of freely available Earth science data in the world, with over 12,400 datasets spanning land, ocean, atmosphere, and cryosphere, collected by dozens of satellite missions, airborne campaigns, and ground stations.

The U.S. Geological Survey’s 3D Elevation Program (3DEP) is a national initiative to provide high-quality, three-dimensional elevation data for the  United States,  including Hawaii, and U.S. territories, and interferometric synthetic aperture radar (IfSAR) elevation data for Alaska. Using technologies such as lidar and ifsar, 3DEP produces detailed information about the shape and height of the land surface.

The Landsat Collection Archive is the long-term archive of Earth observation satellite imagery maintained by the U.S. Geological Survey (USGS) in partnership with NASA. It contains decades of multispectral imagery captured by the Landsat satellite series (Landsat 1 through 9), dating back to 1972. This makes it the longest continuous record of Earth’s land surface from space.

IPUMS International is a project run by the University of Minnesota that collects and standardizes census data from countries around the world. It is a library of downloadable map files (shapefiles) that offers a world map showing country borders, harmonized regional maps, year-specific maps, and European NUTS maps.

GADM (Database of Global Administrative Areas) is a free, detailed digital map database created and maintained by UC Davis researchers. It covers every country in the world and its internal divisions — states, provinces, counties, and smaller units. The data can be downloaded and used in mapping and GIS software to create maps or analyze information by geographic region.

The Copernicus Data Space Ecosystem (CDSE) is the European Union’s official, centralized platform for accessing and processing Earth observation data from the Copernicus Program’s Sentinel satellites. It provides free access to imagery and derived products from the Sentinel satellite missions, as well as complementary environmental and geospatial datasets.

EarthWorks, developed by Stanford University Libraries’ Geospatial Center, is an online geospatial data discovery portal. Users can search, preview, and download thousands of GIS collections and other geographic datasets and maps from Stanford and partner institutions. Earthworks provides:

• Raster datasets
• Digital elevation models
• Historical and contemporary maps
• Satellite and aerial imagery
• Shapefiles and geodatabases

The European Data Portal is the EU’s central open data hub, providing open data published by EU institutions, national portals of EU member states and non-member states, as well as international organizations of predominantly European scope. Users can download statistical and socioeconomic data, find GIS and environmental datasets, find transportation and infrastructure information, and develop maps, applications, and data visualizations.

GeoNetwork is a free, open-source metadata catalog and geospatial data management system used to organize, describe, discover, and share geographic datasets, maps, imagery, and web services. It is widely used by governments, international organizations, and spatial data infrastructures (SDIs) around the world.  Note that GeoNetwork does not perform spatial analysis. Instead, it acts as a catalog system that helps users find and manage geospatial resources and the metadata that describes them.

GeoNode is a free, open-source geospatial data management and web mapping platform that enables organizations to publish, share, visualize, and collaboratively manage geographic data such as vector and raster datasets, maps, and web services, through a web browser. It is widely used to build spatial data infrastructures (SDIs), open data portals, and collaborative mapping websites.

GADM (Database of Global Administrative Areas) is a free, detailed digital map database created and maintained by UC Davis researchers. It covers every country in the world and its internal divisions — states, provinces, counties, and smaller units. The data can be downloaded and used in mapping and GIS software to create maps or analyze information by geographic region.

The Google Earth Engine (GEE) Data Catalog is one of the largest free online collections of satellite imagery, environmental data, and other geographic datasets covering the entire Earth. It currently includes more than 1,000 curated datasets, including near-real-time satellite imagery. Note that most analyses using the Google Earth Engine platform require basic programming skills in JavaScript or Python.

The Humanitarian Data Exchange (HDX)  is the UN’s central open data platform for humanitarian crises. Managed by the United Nations Office for the Coordination of Humanitarian Affairs (OCHA), HDX provides access to datasets used in humanitarian response, disaster relief, and sustainable development. It serves as a central repository where governments, NGOs, international organizations, and researchers can share and discover data related to crises and vulnerable populations.

Natural Earth is a free, public domain map dataset available at three levels of detail, designed for making clean, visually appealing maps with standard mapping or GIS software. It includes country boundaries, states and provinces, cities, rivers, lakes, coastlines, and physical features of the Earth. 

OpenStreetMap (OSM) is a digital map database of the world built through crowdsourced volunteered geographic information. It is supported by the nonprofit OpenStreetMap Foundation, and its data is freely available for visualization, query, download, and modification under open licenses. It provides detailed geographic information on roads, buildings, parks, waterways, public transportation, and millions of places such as schools, hospitals, restaurants, and landmarks.

SEDAC (Socioeconomic Data and Applications Center) is one of NASA’s Distributed Active Archive Centers (DAACs) and serves as NASA’s archive for socioeconomic and environmental data. SEDAC integrates social, economic, and demographic information with Earth science data to support research on human-environment interactions.

The UN Geospatial Hub provides geographic and map data, including country boundary outlines, administrative units, coastlines, rivers, roads, railways, airports, populated places, and urban areas at various scales, thematic maps, satellite imagery, and real-time monitoring tools. It also provides United Nations maps and data focused on the UN’s Sustainable Development Goals (SDGs), peacekeeping operations, and humanitarian responses.

LandScan Global is a high-resolution population dataset that provides a global population distribution with about a 1-kilometer resolution. Developed by Oak Ridge National Laboratory, it provides detailed gridded population data that represent the average population distribution over a 24-hour period. It works with standard GIS software like QGIS, and is particularly valuable for any project involving population geography, urban growth, public health, or environmental hazards.