r: 470,131 sq km

note: includes only the 50 states and District of Columbia

Area - comparative: about one-half the size of Russia; about
three-tenths the size of Africa; about one-half the size of South
America (or slightly larger than Brazil); slightly larger than
China; about two and one-half times the size of Western Europe

Land boundaries: total: 12,248 km

border countries: Canada 8,893 km (including 2,477 km with Alaska),
Cuba 29 km (US Naval Base at Guantanamo Bay), Mexico 3,326 km

note: Guantanamo Naval Base is leased by the US and thus remains
part of Cuba

Coastline: 19,924 km

Maritime claims: contiguous zone: 24 NM

continental shelf: not specified

exclusive economic zone: 200 NM

territorial sea: 12 NM

Climate: mostly temperate, but tropical in Hawaii and Florida,
arctic in Alaska, semiarid in the great plains west of the
Mississippi River, and arid in the Great Basin of the southwest; low
winter temperatures in the northwest are ameliorated occasionally in
January and February by warm chinook winds from the eastern slopes
of the Rocky Mountains

Terrain: vast central plain, mountains in west, hills and low
mountains in east; rugged mountains and broad river valleys in
Alaska; rugged, volcanic topography in Hawaii

Elevation extremes: lowest point: Death Valley -86 m

highest point: Mount McKinley 6,194 m

Natural resources: coal, copper, lead, molybdenum, phosphates,
uranium, bauxite, gold, iron, mercury, nickel, potash, silver,
tungsten, zinc, petroleum, natural gas, timber

Land use: arable land: 19%

permanent crops: 0%

permanent pastures: 25%

forests and woodland: 30%

other: 26% (1993 est.)

Irrigated land: 207,000 sq km (1993 est.)

Natural hazards: tsunamis, volcanoes, and earthquake activity around
Pacific Basin; hurricanes along the Atlantic and Gulf of Mexico
coasts; tornadoes in the midwest and southeast; mud slides in
California; forest fires in the west; flooding; permafrost in
northern Alaska, a major impediment to development

Environment - current issues: air pollution resulting in acid rain
in both the US and Canada; the US is the largest single emitter of
carbon dioxide from the burning of fossil fuels; water pollution
from runoff of pesticides and fertilizers; very limited natural
fresh water resources in much of the western part of the country
require careful management; desertification

Environment - international agreements: pa