Images

The western region of Australia's Great Sandy Desert is an area almost devoid of sand, but characterized by complex geology.

The so-called Richat Structure is a geological formation in the Maur Adrar Desert in the African country of Mauritania. Although it resembles an impact crater, the Richat Structure formed when a volcanic dome hardened and gradually eroded, exposing the onion-like layers of rock.

In an area north of the city of Al-Basrah, Iraq, which borders Iran, a former wetland has been drained and walled off. Now littered with minefields and gun emplacements, it is a staging area for military exercises.

Akpatok Island lies in Ungava Bay in northern Quebec, Canada. Accessible only by air, Akpatok Island rises out of the water as sheer cliffs that soar 500 to 800 feet (150 to 243m) above the sea surface. The island is an important sanctuary for cliff-nesting seabirds.

Utah’s Green River flows south across the Tavaputs Plateau (top) before entering Desolation Canyon (center). The Canyon slices through the Roan and Book Cliff--two long, staircase-like escarpments. Nearly as deep as the Grand Canyon, Desolation Canyon is one of the largest unprotected wilderness areas in the American West.

Landsat 7 captured this image of center-pivot irrigation (green circles) in the Saudi Arabian desert in 2000. Images taken of the same location over several decades show the explosive increase of irrigated land over time, as hidden reserves of water have been tapped beneath desert sands to grow grains, fruits, and vegetables.

This Landsat image displays the Eyjabakkajökull Glacier, an outlet glacier of the Vatnajökull ice cap in Iceland. (N64.6756, W15.5843)

Landsat 7 Path 216 Row 15
Acquired September 16, 2000

Lines and shapes etched into the surface of Antarctica's Robinson Glacier hint at the slow but inevitable movements of this giant river of ice. Patterns of lines may be icefalls, where a glacier cascades over rock, or a series of crevasses, massive cracks that form as different parts of a glacier move at slightly different speeds.

The Lambert Glacier in Antarctica is the world's largest glacier. The focal point of this image is an icefall that feeds into the glacier from the vast ice sheet covering the polar plateau. Ice flows like water, albeit much more slowly.

Guinea-Bissau is a small country in West Africa. Complex patterns can be seen in the shallow waters along its coastline, where silt carried by the Geba and other rivers washes out into the Atlantic Ocean.

This scar on an arid landscape is the dry riverbed of the Ghadamis River in the Tinrhert Hamada Mountains near Ghadamis, Libya.

The Dasht-e Kevir, or Great Salt Desert, is the largest desert in Iran. It is a primarily uninhabited wasteland, composed of mud and salt marshes covered with crusts of salt that protect the meager moisture from completely evaporating.

The Mayn River, seen here with what is thought to be a portion of the Anadyr River, flows through the far northeastern corner of Siberia.

Known for its beaches and resort hotels, Cancun lies at the tip of Mexico's Yucatan Peninsula. Inland from this tourist mecca, however, lies a sparsely populated tropical scrub forest that shelters the ruins of ancient Mayan cities.

Along Greenland’s western coast, a small field of glaciers surrounds Baffin Bay.

Fed by multiple waterways, Brazil's Negro River is the Amazon River's largest tributary. The mosaic of partially-submerged islands visible in the channel disappears when rainy season downpours raise the water level.

The tongue of the Malaspina Glacier, the largest glacier in Alaska, fills most of this image. The Malaspina lies west of Yakutat Bay and covers 1,500 sq mi (3,880 sq km).

In a small corner of the vast Great Sandy Desert in Western Australia, large sand dunes—the only sand in this desert of scrub and rock—appear as lines stretching from left to right. The light-colored fan shapes are scars from wildfires.

Once a vast carpet of healthy vegetation, the Amazon rain forest is changing rapidly. This image of Bolivia shows dramatic deforestation in the Amazon Basin. Loggers have cut long paths into the forest, while ranchers have cleared large blocks for their herds. Fanning out from these clear-cut areas are settlements built in radial arrangements of fields and farms.

Namaqualand in South Africa is known as the "gem of the Northern Cape." Portions of this area were turned into a national park in 1999, to preserve the abundant wildlife and brilliant wildflowers native to the area.

Namib-Naukluft National Park is an ecological preserve in Namibia's vast Namib Desert. Coastal winds create the tallest sand dunes in the world here, with some dunes reaching 980 feet (300 meters) in height.