(See detailed map)

This article describes the geography of Guam.

Location

Oceania, island in the North Pacific Ocean, about three-quarters of the way from Hawaii to the Philippines

Geographic coordinates

13° 28′ N, 144° 47′ E

Map references

Oceania

Area

• Total: 541.3 km²
• Land: 541.3 km²
• Water: 0 km²

Area--comparative

Three times the size of Washington, DC

Land boundaries

Approximately 30 miles/51 km long and 9 miles/15.3 km wide, narrowing to four miles/6.8 km wide at the center.

Coastline

125.5 km

Maritime claims

• Exclusive economic zone: 200 nm
• Territorial sea: 12 nm

Climate

Tropical marine; generally warm and humid, moderated by northeast trade winds; dry season from January to June, rainy season from July to December; little seasonal temperature variation

Terrain

Volcanic origin, surrounded by coral reefs; relatively flat coralline limestone plateau (source of most fresh water), 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 m
• Highest point: Mount Lamlam 406 m

Natural resources

Commerical fishing (mostly servicing and unloading of long line fleets and commerical vessels), sport fishing of blue marlin, wahoo, mahi mahi, yellow fin tuna, and deep water reef fish, tourism (especially from Japan but increasingly from China and Korea)

Land use

• Arable land: 11%
• Permanent crops: 11%
• Permanent pastures: 15%
• Forests and woodland: 18%
• Other: 45% (1993 est.)

Irrigated land

NA km²

Natural hazards

Frequent squalls during rainy 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, an exotic species. Island also supports feral populations of introduced deer, pigs and water buffalo.

Geography--note

Largest and southernmost island in the Mariana Islands archipelago; strategic location in western North Pacific Ocean

See also: Guam