This article describes the geography of the United States territory of Guam.
Location
Oceania, island in the North Pacific Ocean, about a quarter of the way from the Philippines to Hawaii, United States
Geographic coordinates
13°26′31″N 144°46′35″E
Map references
Oceania
Area
Total: 544 km²
Land: 544 km²
Water: 0 km²
Area (comparative)
Three times the size of Washington, D.C.
Land boundaries
Approximately 30 miles (51 km) long and 9 miles (15 km) wide, narrowing to 4 miles (7 km) at the center.
Coastline
125.5 km (78.0 mi)
Maritime claims
Territorial sea: 12 nm (22.224 km)
Exclusive economic zone: 200 nm (370.4 km)
The southern maritime boundary of Guam forms a border with the Federated States of Micronesia, and the northern maritime boundary forms a border with the Commonwealth of the Northern Marianas Islands.
Climate
Tropical marine; generally warm and humid, moderated by northeast trade winds; dry season from January to June, wet season from July to December; little seasonal temperature variation.
Terrain
Volcanic origin, surrounded by coral reefs; relatively flat coralline limestone plateau (source of most freshwater), with steep coastal cliffs and narrow coastal plains in north, low-rising hills in center, mountains in south
Elevation extremes
Lowest point: Pacific Ocean, 0 metres (0 ft)
Highest points:
- Mount Lamlam, 406 meters (1,332 ft)
- Mount Jumullong Manglo, 391 meters (1,283 ft)
- Mount Bolanos, 368 meters (1,207 ft)
Natural resources
Commercial fishing (mostly servicing and unloading of longline fleets and commercial vessels), recreational fishing of Indo-Pacific Blue Marlin (
Makaira mazara), Wahoo (
Acanthocybium solandri), Mahi-mahi (
Coryphaena hippurus), Yellowfin tuna (
Thunnus albacares), and deepwater reef fish, tourism (especially from Japan but increasingly from China and South Korea).
Land use
Arable land: 1.85%
Permanent crops: 16.67%
Other: 81.48% (2012 est.)
Irrigated land
2
km2
Natural hazards
Frequent squalls during wet season; relatively rare, but potentially very destructive typhoons (typhoons are possible in any season but most common from August through December)
Environment - current issues
Extirpation of native bird population by the rapid proliferation of the Brown tree snake (
Boiga irregularis), an exotic species. Island also supports feral populations of introduced deer, Pigs (
Sus scrofa) and Carabao (
Bubalus bubalis carabanesis).
Geography - note
Largest and southernmost island in the Mariana Islands archipelago; strategic location in western North Pacific Ocean.
