Thematic Maps on the Web

United States

Atlases

• American Panorama - an atlas of U.S. history
• Atlas of the Historical Geography of the U.S.

Climate

• Air Quality Map (U.S. Environmental Protection Agency)
• Climate Map (NOAA)
• Drought Map (U.S. Drought Monitor)
• Flood Maps (FEMA)
• Hurricane Landfalls 1950-2004 (NOAA)
• Active Fire Mapping Program (USDA National Interagency Fire Center)

Communication

• Area Code Maps (NANPA)

Energy

• Biomass Maps (NREL)
• Gasoline Price Map (Gasbuddy.com)
• Geothermal Potential Map (Southern Methodist University)
• Renewable Energy Atlas of the West 
• Solar Energy Maps (National Renewable Energy Laboratory [NREL])
• Water Use Maps (U.S. Geological Survey)
• Wind Maps (NREL)

Public Health

• Covid Data Tracker (CDC)
• EJSCREEN -Environmental Justice Screening and Mapping Tool (EPA)
• HIV/AIDS Maps (Frontline/PBS)
• Influenza Map, Weekly (U.S. Centers for Disease Control)
• Adult Obesity Prevalence Map (CDC)
• Pesticide Maps (USGS)

Land Use / Geography

• Ground Water Atlas (USGS)
• Gulf of Mexico Region Low-Lying Areas U.S. Geological Survey, 2008
• Historic Trails System Map U.S. Forest Service, 2007
• National Parks Clickable Map (National Park Service)
• National Wetlands Inventory - U.S. Fish and Wildlife Service
• Relief Maps (3-D shaded relief) (Andrew Birrell)

Population & Demographics 

• US Census Burea Maps & Data
• Ancestry, Top Cities by Ethnic Group (ePodunk)
• Immigration Explorer – Interactive Map (NYT)
• Social Explorer

World

• Perry-Castaneda Library Map Collection (University of Texas)
• ReliefWeb – earthquakes, floods and other natural disasters