Region
- United States 31 results
- Africa 5 results
- India 5 results
- California 4 results
- Great Britain 4 results
- OECD countries 3 results
- Carlsbad Region 2 results
- New Mexico 2 results
- Africa, Sub-Saharan 1 results
- Atlanta 1 results
- Atlanta (Ga.) 1 results
- Caribbean Area 1 results
- Delta Region 1 results
- Delta Region (Calif.) 1 results
- Egypt 1 results
- England 1 results
- Europe 1 results
- Everglades National Park (Fla.) 1 results
- Florida 1 results
- Georgia 1 results
- Great Lakes (North America) 1 results
- Greece 1 results
- Greenland 1 results
- Gulf States 1 results
- Idaho 1 results
- Idaho National Engineering and Environmental Laboratory Region 1 results
- Japan 1 results
- Kurdistan 1 results
- London 1 results
- Mexico, Gulf of 1 results
- Nile River Watershed 1 results
- Scandinavia 1 results
- Soutthern States 1 results