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. Numerous ice floes around the island attract walrus and whales, making Akpatok a traditional hunting ground for native Inuit people.
This abstract in browns and grays from central Algeria shows that some parts of Africa's Sahara Desert contain much more than dunes of wind-blown sand. Barren ridges and fragmented mountains (lower right) border a vast expanse of arid plains etched with a complex system of dry streambeds. The streambeds contain water for brief periods following rare, intense rains that often cause flash floods.
The prominent crimson streak in the center of this image represents the remains of an extensive lava and mud flow. Its source is the currently dormant Anyuyskiy Volcano orange circular shape at the right end of the streak) in northeastern Russia. Remote and largely inaccessible, the region is a rugged collection of towering volcanic peaks, steep valleys, and wild, snow-fed rivers and streams.
Like sweeping brushstrokes of pink and green, the Belcher Islands meander across the deep blue of Canada's Hudson Bay. The islands' only inhabitants live in the small town of Sanikiluaq, near the upper end of the middle island. Despite the green hues in this image, these rocky islands are too cold to sustain more than a smattering of low-growing vegetation.
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. Healthy vegetation appears bright red in this image.
Truly a river of ice, Antarctica's relatively fast-moving Byrd Glacier courses through the Transantarctic Mountains at a rate of 0.8 kilometers (0.5 miles) per year. More than 180 kilometers (112 miles) long, the glacier flows down from the polar plateau (left) to the Ross Ice Shelf (right). Long, sweeping flow lines are crossed in places by much shorter lines, which are deep cracks in the ice called crevasses. The conspicuous red patches indicate areas of exposed rock.
Snow-capped Colima Volcano, the most active volcano in Mexico, rises abruptly from the surrounding landscape in the state of Jalisco. Colima is actually a melding of two volcanoes, the older Nevado de Colima to the north and the younger, historically active Volcan de Colima to the south. Legend has it that gods sit atop the volcano on thrones of fire and ice.
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.
In the American Southwest, transitions from one ecosystem to another can be dramatic and abrupt. This certainly is true in northern Arizona, USA, where the parched Painted Desert, shown here in a palette of purples, adjoins Sitgreaves National Forest (shades of green), a realm of pine woodlands with abundant wildlife. Within the Painted Desert lie the Hopi Buttes, a field of ancient volcanic cones, seen here as a scattering of dark, circular shapes near the top of the image.
Center pivot irrigation systems created these circular patterns in crop land near Garden City, Kansas. The red circles indicate irrigated crops of healthy vegetation. The light-colored circles represent harvested crops.
Ethereal swirls of grease ice appear turquoise against the midnight blue of the northern Baltic Sea near the Aland Islands (red) between Finland and Sweden. An early stage of sea ice formation, grease ice consists of a viscous mix of tiny ice crystals and resembles an oil slick on the ocean's surface. Wind and currents constantly shape and reshape grease ice into surreal, ghostly patterns.
Soaring, snow-capped peaks and ridges of the eastern Himalaya Mountains create an irregular white-on-red patchwork between major rivers in southwestern China. The Himalayas are made up of three parallel mountain ranges that together extend more than 2,900 kilometers.
Along the southeastern coast of Greenland, an intricate network of fjords funnels glacial ice to the Atlantic Ocean. During the summer melting season, newly calved icebergs join slabs of sea ice and older, weathered bergs in an offshore slurry that the southward-flowing East Greenland Current sometimes swirls into stunning shapes. Exposed rock of mountain peaks, tinted red in this image, hints at a hidden landscape.
This stretch of Iceland's northern coast resembles a tiger's head complete with stripes of orange, black, and white. The tiger's mouth is the great Eyjafjorour, a deep fjord that juts into the mainland between steep mountains. The name means "island fjord," derived from the tiny, tear-shaped Hrisey Island near its mouth. The ice-free port city of Akureyri lies near the fjord's narrow tip, and is Iceland's second largest population center after the capital, Reykjavik.
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.
During the last ice age, Akimiski Island in Canada's James Bay lay beneath vast glaciers that pressed down with immense force. As the climate changed and the ice retreated, Akimiski began a gradual rebound. The island's slow but steady increase in elevation is recorded along its naturally terraced edges where the coastline seems etched with bathtub rings, the result of the rising landmass and wave action at previous sea levels.
The eastern side of Russia's Kamchatka Peninsula juts into the Pacific Ocean west of Alaska. In this winter image, a volcanic terrain is hidden under snow-covered peaks and valley glaciers feed blue ice into coastal waters.
The Lena River, some 2,800 miles(4,500km) long, is one of the largest rivers in the world. The Lena Delta Reserve is the most extensive protected wilderness area in Russia. It is an important refuge and breeding grounds for many species of Siberian wildlife.
Small, blocky shapes of towns, fields, and pastures surround the graceful swirls and whorls of the Mississippi River. Countless oxbow lakes and cutoffs accompany the meandering river south of Memphis, Tennessee, on the border between Arkansas and Mississippi, USA. The "mighty Mississippi" is the largest river system in North America.
Turbid waters spill out into the Gulf of Mexico where their suspended sediment is deposited to form the Mississippi River Delta. Like the webbing on a duck's foot, marshes and mudflats prevail between the shipping channels that have been cut into the delta.
Clouds encircle the lofty rim of Africa's Mount Elgon, a huge, long-extinct volcano on the border between Uganda and Kenya. The solitary volcano has one of the world's largest intact calderas, a cauldron-like central depression. The caldera is about 6.5 kilometers (4 miles) across and formed following an eruption, when the emptied magma chamber collapsed under the weight of volcanic rock above it.
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.
Mimicking a cubist collage, linear windbreaks of densely planted trees surround farmsteads in this winter landscape near the city of Komsomolets in Northern Kazakhstan.
Like a watercolor in which a brushstroke of dark green has bled into a damp spot on the paper, southern Africa's Okavango River spreads across the pale, parched landscape of northern Botswana to become the lush Okavango Delta. The delta forms where the river empties into a basin in the Kalahari Desert, creating a maze of lagoons, channels, and islands where vegetation flourishes, even in the dry season, and wildlife abounds.
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.
What appears to be a stroke of thick red paint is actually a remarkable interplay of light and cloud in the Canadian Rockies. Angling through them is part of the Rocky Mountain Trench, a valley that extends from Montana, USA, to just south of the Yukon Territory. Low clouds filled a part of the Trench near the border between the Canadian provinces of Alberta and British Columbia. The light-reflecting nature of the clouds coupled with low sun elevation resulted in this startling effect.
Vivid colors and bizarre shapes come together in an image that could be an imaginative illustration for a fantasy story. This labyrinth of exotic features is present along the edge of Russia's Chaunskaya Bay (vivid blue half circle) in northeastern Siberia. Two major rivers, the Chaun and Palyavaam, flow into the bay, which in turn opens into the Arctic Ocean. Ribbon lakes and bogs are present throughout the area, created by depressions left by receding glaciers.
In the style of Van Gogh's painting "Starry Night," massive congregations of greenish phytoplankton swirl in the dark water around Gotland, a Swedish island in the Baltic Sea. Phytoplankton are microscopic marine plants that form the first link in nearly all ocean food chains. Population explosions, or blooms, of phytoplankton, like the one shown here, occur when deep currents bring nutrients up to sunlit surface waters, fueling the growth and reproduction of these tiny plants.
After beginning in northern British Columbia and flowing through Yukon in Canada, the Yukon River crosses Alaska, USA, before emptying into the Bering Sea. Countless lakes, sloughs, and ponds are scattered throughout this scene of the Yukon Delta. The river's sinuous, branching waterways seem like blood vessels branching out to enclose an organ. It is one of the largest river deltas in the world, and currently (2010) protected as part of the Yukon Delta National Wildlife Refuge.