Region
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Marshall Islands
3
Michigan
3
Nevada
3
North Atlantic Ocean
3
Oregon
3
Outer space
3
Pacific Coast
3
Scotland
3
Spain
3
Tennessee
3
Turkey
3
Tuvalu
3
Wisconsin
3
Acadia National Park
2
Acadia National Park (Me.)
2
Africa, East
2
America
2
Appalachian Mountains
2
Arizona
2
Asia, Central
2
Athabasca Tar Sands
2
Athabasca Tar Sands (Alta.)
2
Atlantic Coast (North America)
2
Bahamas
2
Baltic Sea
2
Bering Sea
2
Bhutan
2
California, Southern
2
Cameroon
2
Chesapeake Bay (Md. and Va.)
2
Chile
2
Colorado River (Colo.-Mexico)
2
Cook Inlet Region
2
Developing island countries
2
Devils Postpile National Monument
2
Devils Postpile National Monument (Calif.)
2
Easter Island
2
El Ni䮯 Current
2
El Salvador
2
Europe, Northern
2
Fiji
2
Glen Canyon (Utah and Ariz.)
2
Government policy
2
Grand Teton National Park
2
Grand Teton National Park (Wyo.)
2
Great Lakes Region (North America)
2
Guyana
2
Hesse
2
Iberian Peninsula
2
Indiana
2
more ...