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State of Flux - Images of Change

Each week the State of Flux features images of different locations on planet Earth, showing change over time periods ranging from centuries to days. Some of these effects are related to climate change, some are not. Some document the effects of urbanization, or the ravage of natural hazards such as fires and floods. All show our planet in a state of flux.

Left: October 23, 2009. Right: April 1, 2010. The Sudd is a vast swamp in southern Sudan, where the Nile River wanders for about 640 kilometers (400 miles). During the wet season from April to October, the Sudd grows to about 10 times its area during the dry season, covering some 80,000 square kilometers (about 31,000 square miles). This yearly flooding pattern is crucial to the local flora and fauna and to the local Nilotic people's way of life. <br><br> The Jonglei Canal project was designed to reroute the Nile around the wetland, reducing evaporative loss, increasing the water available downstream for irrigation and cutting the travel distance from Khartoum to Juba, the main city in the south, by 300 kilometers (almost 190 miles). Opponents to the project say that it would negatively impact local agriculture, cattle raising, fishing and access to drinking water, among other concerns. The canal was conceived over half a century ago, but military conflict stopped construction in 1983.

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LATEST IMAGE: Sudd Swamp
Left: October 23, 2009. Right: April 1, 2010. The Sudd is a vast swamp in southern Sudan, where the Nile River wanders for about 640 kilometers (400 miles). During the wet season from April to October, the Sudd grows to about 10 times its area during the dry season, covering some 80,000 square kilometers (about 31,000 square miles). This yearly flooding pattern is crucial to the local flora and fauna and to the local Nilotic people's way of life.

The Jonglei Canal project was designed to reroute the Nile around the wetland, reducing evaporative loss, increasing the water available downstream for irrigation and cutting the travel distance from Khartoum to Juba, the main city in the south, by 300 kilometers (almost 190 miles). Opponents to the project say that it would negatively impact local agriculture, cattle raising, fishing and access to drinking water, among other concerns. The canal was conceived over half a century ago, but military conflict stopped construction in 1983. Click here to download image.
Credit: Source: United Nations Environment Programme (UNEP). From Africa Water Atlas (2010); Division of Early Warning and Assessment (DEWA), UNEP, Nairobi, Kenya.


MORE IMAGES OF CHANGE
Left: June 9, 2007. Right: June 12, 2008. Thunderstorms on June 6 and 7, 2008, produced up to 10 inches of rain in some areas of central and western Indiana. On June 9, President Bush declared 29 Indiana counties a major disaster area. A record flood stage of 34 feet (10 meters) was expected at the city of Mt. Carmel, Illinois, located at the confluence of the Wabash and White Rivers. On June 12 (right image), the Wabash River, which separates Illinois to the east and Indiana to the west, was beginning to reach its crest of 22 to 25 feet (6.7 to 7.6 meters) at the city of Vincennes, Indiana. At several locations, the Wabash River swelled to over 4 miles (6.4 kilometers) wide.

Thunderstorms produce flood		 Left: August 21, 1985. Right: August 29, 2011. The Caspian Sea is the world’s largest landlocked body of water, and it’s getting bigger. In the past couple of decades, heavy rains in the greater Volga Basin have greatly increased the incoming flow from the Volga River, the Caspian’s primary source of water. These images show a small portion of the shoreline. In the 2011 image, coastal settlements have been flooded, displacing inhabitants and shutting down industrial facilities. The groundwater level has also risen, leading to swamping and increasing the salinity of lowland territories. Tyuleniy Island (the prominent island) has visibly lost land mass, with the rising water contributing to the decline of the island and the marshes around it that support fowl and other animals.

Rising waters		 Left: September 21, 1985. Right: September 10, 2010. Owens Lake lies in the Owens Valley between the Sierra Nevada and Inyo Mountains, about 130 miles north of Los Angeles, California. For thousands of years, it was one of the most important stopover sites in the western U.S. for migrating waterfowl and shore birds. However, in the early 20th century, the lower Owens River, which fed the lake, was largely diverted to the Los Angeles aqueduct. Water from springs and artesian wells kept some of the lake alive, but toxic chemicals and dust impinged on the regional environment and disturbed the bird habitat. Beginning in 1999, a plan was put in place to restore the lake region and alleviate the dust build-up, using ponds, native grasses, gravel deposits and limited shallow flooding.

Owens Lake bounces back		 Left: March 21, 2005. Center: July 27, 2005. Right: February 10, 2011. In 2005, large fires caused extensive damage to the forests of the Cordillera Central, which are mountains in the Dominican Republic. The fires started on the lower reaches of Pico Duarte, the country’s highest mountain. Flames raced up the mountain, consuming the pine, palm and broadleaf rainforests that grow at higher elevations. The left-hand image shows the region during the fires (red). The center image shows the extent of the fire scars (brown) and the grasses (light green) that grow more quickly than tree stands. On the right, the image shows forest regrowth (dark green) covering the fire scars. The rate of regrowth is being monitored because newly exposed, steep-sloped soils are more vulnerable to erosion, thereby affecting water quality in the downslope rivers, which are the region’s principal source of drinking water.

Burned forest recovers		 DEAD SEA SHRINKS<br><br> Left: November 9, 1984. Right: November 28, 2011. The Dead Sea lies in the Jordan Rift Valley, bordering Jordan, Israel and the West Bank. It is one of the world's saltiest bodies of water, too salty to harbor any life other than bacteria. Minerals from the sea, however, are extracted for various industrial purposes. Mineral evaporation ponds have replaced open water in the southern part of the sea, as can be seen in the 2011 image. In recent decades, the Dead Sea has shrunk as water has been diverted from the Jordan River, the sea's main tributary. A plan has been announced to replenish the Dead Sea by building a canal from the Red Sea, providing fresh (desalinated) water to Jordan en route.

Dead Sea shrinks
Left: August 17, 1992. Right: August 3, 2010. These images illustrate major changes in agricultural practices in the Mexican state of Chihuahua. Increased diversion of water from the Luis L. Leon Reservoir for agricultural irrigation has affected vegetation patterns in the northeastern part of Chihuahua and significantly reduced the amount of water reaching the Rio Grande River. Farmers use center pivot irrigation systems (marked by red circles) to grow alfalfa and sorghum for dairy farms and cattle feedlots. The drop in water supplying the Rio Grande seriously threatens wildlife habitat and natural vegetation.

Irrigation expansion		 Left: November 1984. Right: November 2009. The Inner Niger Delta is the largest wetland in Western Africa. It spreads out along a flat 200-kilometer (124-mile) stretch of the Niger River as it passes through the Sahel on its way to the southern edges of the Sahara Desert. The delta supports about one million people and a variety of ecosystem goods and services, including a productive fishery, pasture for sheep and cattle, land and water for agriculture and habitat for natural flora and fauna. The flooding that replenishes the wetland depends mainly on rainfall over the upper Niger River in the Guinean Highlands, and to a lesser extent in the Bani watershed in northern Côte d'Ivoire. Rainfall over the delta itself contributes only 5 to 10 percent of the delta’s water. The 1984 image was taken during a prolonged drought, while the 2009 image follows a year of more normal precipitation.

Wetland ebb and flow		 Left: August 12, 1986. Right: August 1, 2011. Arcadia Lake is a reservoir located near Edmond, Oklahoma, a suburb of Oklahoma City. It was built in the 1980s to control floods in the Deep Fork River Basin, to supply water to the city of Edmond and to provide recreational resources to the surrounding communities. Construction was a cooperative effort between the city of Edmond and the U.S. Army Corps of Engineers, but the two parties are now engaged in a lawsuit over water allocation and maintenance costs. These images show the area shortly before the earthen dam blocked the Deep Fork River (left) and with the reservoir near capacity (right).

Arcadia Lake		 Left: October 24, 2007. Right: December 23, 2011. A volcano erupted in the Red Sea in December 2011, apparently creating a new island. According to news reports, fishermen witnessed lava fountains reaching up to 30 meters (nearly 100 feet) high on December 19. By December 23, what looked like a new island had appeared. A thick plume can be seen in the 2011 image, dark near the bottom and light near the top, perhaps a mixture of volcanic ash and water vapor. The activity occurred along the Zubair Group, a collection of small islands off the west coast of Yemen. Running in a roughly northwest-southeast line, the islands poke above the sea surface, rising from a shield volcano. This region is part of the Red Sea Rift, where the African and Arabian tectonic plates pull apart and new ocean crust regularly forms.

New island appears		 The Aral Sea, located in Kazakhstan and Uzbekistan in central Asia. Left: June 4, 1977. Center left: September 17, 1989. Center right: May 27, 2006. Right: June 3, 2009. Once one of the largest inland bodies of salty water in the world and the second largest sea in Asia — 70,000 square kilometers or 27,000 square miles in area — the Aral Sea has shrunk dramatically over the last 30 years. One of the main reasons is crop irrigation: water has been drawn off from the rivers that kept the Aral Sea filled. As the sea has shrunk, the local climate has become harsher, there have been contaminated dust storms, and drinking water and the local fishing industry have been lost. By the late 2000s, the Aral Sea had lost four fifths of its water volume. For additional images of the changing Aral Sea, see “Aral Gone Awry.”

The vanishing Aral Sea
Left: April 16, 2011. Right: May 18, 2011. In 2011, an extremely snowy winter and several intense rainstorms upstream caused the lower Mississippi River to rise to extremely high levels. To relieve pressure on downstream levees that protect Baton Rouge and New Orleans, gates at the Morganza Spillway were opened. The April image shows the area before the gates were opened; the May image shows the scene afterwards. The released water inundated the Atchafalaya River Basin, displacing more than 25,000 residents. Also see “Flooding Devastates U.S. Midwest” for another view of the floods caused by the Mississippi River.

Mississippi River Flooding		 Patagonia, Chile. Left: September 18, 1986. Right: August 5, 2002. The 1986 image shows the region prior to a major retreat of the glaciers. The 2002 image shows a retreat of nearly 10 kilometers (6.2 miles) of the glacier on the left side. The smaller glacier on the right has receded more than 2 kilometers (1.2 miles.) In front of the smaller glacier, two ribbon lakes have formed behind the debris left by the glacier's advance. Scientists and government managers are using satellite imagery like this to monitor the retreat of the glaciers and the impact on water bodies caused by the changes in the glaciers’ size and direction.

Retreating glaciers		 Left: January 29, 1974. Right: February 16, 2008. An influx of people from rural areas has increased the city of Kampala’s population by an average of 5.6 percent per year since the 1960s. The urban area is now made up of a sprawling 197 square kilometers (76 square miles). Though it is Uganda’s capital city, Kampala’s infrastructure is inadequate for many of the more than 1.2 million people who live there today. Forests in and around the city have been cut down to produce charcoal, and many of the area’s wetlands have been lost to industrial and residential development. As a result, water quality within Kampalahas worsened, and Murchison Bay (top part of the body of water seen in these images)has suffered periodic infestations of water hyacinth and massive algal blooms that turn the water green.

City expansion		 Left: May 25, 1985. Right: June 7, 2010. The Paraguay-Parana River system is the second largest river system in South America — second only to the Amazon. More than 100 million people and some of the rarest species on Earth depend on its waters for survival. The 1985 image shows a section of the river system shortly after construction began on the Yacyretá Dam, a joint hydroelectric project between Paraguay and Argentina. River levels rose dramatically upon completion of the dam, initially displacing 15,000 residents and endangering the homes of 800,000 more. Flooded lands included the habitats of jaguars, giant river otters, maned wolves, giant anteaters, 650 species of birds and more than 10,000 species of plants.

Dam impacts		 Left: October 1, 2010. Right: October 4, 2011. Dry conditions since mid-2010 have caused a large portion of Texas to be in an “exceptional” state of drought, the worst condition on the Federal government’s drought monitor scale. The 12-month period between October 2010 and September 2011 was the driest in Texas since 1895, when the state began keeping rainfall records. Not only have crops and farmland been affected, but the levels of many lakes in the state have also fallen. Seen here is the area surrounding Proctor Lake, southwest of Dallas. Much of 2010’s green vegetation has given way to barren ground (lighter shades) in 2011. Reduced water levels from the two major feeder rivers, the Sabanna and Leon Rivers, are responsible for the lake’s receding shoreline. Proctor Lake reservoir was created by the U.S. Army Corps of Engineers in 1963 as a flood-control measure, and provides drinking water and recreation facilities to neighboring communities.

Drought shrinks Proctor Lake
Left: September 7, 2009. Center: July 16, 2010. Right: August 1, 2010. Extreme drought on the Kamchatka Peninsula in eastern Siberia led to a series of major fires in 2010. The 2009 image shows the area before the fires began. At lower left is the Penzhinskaya Guba (bay). Green colors show vegetation and white/gray shades represent clouds. In the center picture, a major burn is visible in the low lands. The dark color shows burned area; light blue shows smoke. In the picture on the right, the burned area has expanded and additional fires have broken out in the lower right. By early August, an area more than 30 miles (48 kilometers) wide had burned. Regional resource managers and fire-fighting officials used data from the Landsat satellite to monitor the fires and their impact on vegetation.

Wildfires		 The expansion of surface mining in West Virginia. Left: June 6, 1987. Right: June 8, 2011. More than half of the U.S.’ electrical power comes from coal burning and a large percentage of that coal comes from West Virginia. Of the nearly 150 million tons of coal extracted each year from the state’s mines, an increasing amount (60 million tons in 2009) comes from surface mining and mountaintop removal. Mountaintop removal can have serious impacts on the health of local people — through the pollution of groundwater by mine runoff and exposure to airborne toxins and dust — and on the environment — through permanent loss of critical ecosystems, destruction of forests and loss of streams. Scientific evidence suggests that these impacts are pervasive and irreversible and that efforts to reclaim the disturbed land can’t make up for the impacts felt by the mining process.

Surface coal mining		 Left: July 4, 2000. Right: May 30, 2004. Ten days of heavy rains caused flooding and landslides in the Dominican Republic and Haiti. More than 1,000 people were reported to have died, with another 1,600 missing and 25,000 in need of emergency food and other assistance. The flooding was driven by a week of intense rainfall—some 50 centimeters (nearly 20 inches) across the border areas of the two countries. The destruction was especially severe thanks to deforestation in the drainage basins and the construction of settlements on the floodplains and other low areas. These images cover an area of about 15 x 17 kilometers (9 x 10 miles) centered on the town of Jimani, in the Dominican Republic.

Flooding in Dominican Republic & Haiti		 Lake Basaka, Central Rift Valley of Ethiopia. Left: January 18, 1985. Right: January 10, 2011. Lake Basaka has expanded greatly during the past 35 years, raising the groundwater table and increasing the salinity of water reserves. That salinity has impacted regional sugarcane production, a major source of income for the region, and many agricultural fields have been abandoned. While the cause of the lake’s expansion is still being studied, a likely cause is the discharge of excess irrigation water directly into the lake.

Expansion of Lake Basaka		 Left: October 25, 1993. Right: October 27, 2011. Noted as one of the fastest growing cities in Mexico, Aguascalientes is home to many manufacturers. Over the past 10 years, the urban area of Aguascalientes has spread into neighboring municipalities, some of which have been annexed into Aguascalientes as suburbs.

Urban growth
Left: August 6, 1987. Right: July 23, 2011. The landscape of Kazakhstan’s Mangystau Province, near the Caspian Sea, has changed since oil and gas deposits in the region began to be exploited in the early 1990s. The 2011 image shows production facilities in the desert with settlements built around them. Increased fossil fuel production in this area has raised concerns about the quality and availability of freshwater needed for rural development and public health.

Oil production expands		 Left: Jan. 3, 1974 to Dec. 26, 1978. Center: Oct. 16, 2001. Right: Jan. 18, 2010. When Lake Faguibine, in northern Mali, is full, as it was in the 1970s (left), it is among the largest lakes in West Africa, covering approximately 590 square kilometers (228 square miles). During the great droughts of the 1970s and 1980s, Faguibine began shrinking and in the 1990s it dried up completely. With the lake all but gone, many local livelihoods also dried up, including agriculture, fishing and dry-season grazing. Despite some better rainfall years since the 1990s, Lake Faguibine has not significantly refilled, only forming a small pond for a few years during the wet seasons. The 2010 wet-season satellite image shows a pool about 35 square kilometers (14 square miles) in area (six percent of the 1974 area).

Drought: West Africa		 Left: September 24, 2010. Right: August 2, 2011. In the spring of 2011, heavy rains and snowpack resulted in record releases from dams in Montana and the Dakotas, and near-record flooding along parts of the Missouri River. One especially hard-hit community was Hamburg, Iowa, where levee failure in early June caused extensive flooding and the evacuation of many homes. By late June, the U.S. Army Corps of Engineers had rebuilt the levees and Hamburg was protected from additional flooding.

Missouri River flooding		 Left: August 7, 1993. Right: July 8, 2011. These images show changes to the western coastline of Sonora, Mexico due to the construction of shrimp farms over the past two decades. While the shrimp industry has generated profits and jobs, there have been concerns about its effect on the ecosystems of the region, and disputes have arisen about property rights to the communal coastal lands.

Changing shoreline		 Left: June 27, 2010. Right: July 5, 2010. Fires broke out along the Volga River near Nizhniy Novgorod, the third largest city in Russia. The July image shows some 3000 acres of burned area in shades of red, as well as smoke from active fires. The June image shows conditions before the fires. The landscape includes natural vegetation, marshy land and crops.

Fires along Volga River
Left: July 2, 1985. Right: June 24, 2011. The Moroccan cities of Agadir, Inezgane and Tikiouine are close to the Atlantic coastline (seen in blue in the images), and stretch into the foothills of the Atlas Mountains. Agadir was nearly destroyed by an earthquake in 1960. Reconstruction has focused on tourism, turning this area into a winter destination. The 1985 image shows the area 25 years into the rebuilding. By 2011, the urban areas reach into the Sahara Desert. Growth has been influenced by the expanding fishing industry and modern commercial ports.

Urban growth		 Dramatic change in the area of the Great Salt Lake over the past 25 years. Left: August 1985. Right: September 2010. The lake was filled to near capacity in 1985 because feeder streams were charged with snowmelt and heavy rainfall. In contrast, the 2010 image shows the lake shriveled by drought. The Promontory Peninsula (protruding into the lake from the top) is surrounded by water on three sides in the first image, but is landlocked on its eastern side in the second. Similarly, Antelope Island was encircled by water in 1985, but was connected to marshy areas in 2010. Mosaics of four satellite images were used to illustrate the changes over the full lake area.

Shrinking of Great Salt Lake		 Left: June 24, 1984. Right: August 6, 2011. The Samuel Dam is located along the Jamari River in Rondônia, Brazil. These images show the area in 1984, shortly after construction of the hydroelectric dam began, and in 2011. The reservoir created by the dam flooded the upstream forest and displaced many people. Also evident in the images is the deforestation that has affected much of the region.

Dam floods forest		 Left: January 31 and February 1, 1973. Right: December 21, 2009. The Mau Forest Complex, which covers more than 400,000 hectares, is Kenya’s largest closed-canopy forest ecosystem and the most important water catchment in the Rift Valley and western Kenya. As part of the catchment for Lake Victoria and the White Nile, the Mau Forest is also of international importance, especially with respect to water quality. But about a quarter of the forest (yellow arrows) has been destroyed since 2000, and the images from 1973 and 2009 capture 36 years of forest loss. The Kenyan government convened a forum in 2009 at which a plan to rehabilitate the forest was proposed, with a budget of US$81 million. By early 2010, a commitment of about US$10 million had been received from international donor governments.

Deforestation in Mau Forest Complex		 Left: April 30, 2011. Right: July 3, 2011. Lightning sparked wildfires near the Okefenokee National Wildlife refuge in the Honey Prairie region of Georgia on April 30, 2011, after the left-hand image was taken. Dry conditions helped fuel the fires and continued lightning strikes started new ones. By July 7, over 290,000 acres had burned. The red tones of the July 3 image represent recovering vegetation in previously burned areas. Light tones are the smoke of active fires.

Wildfires on the Honey Prairie
Left: May 15, 2010. Right: May 18, 2011. The Portage Diversion system was built in 1970 to divert water from the Assiniboine River to an 18-mile channel which empties into Lake Manitoba. The channel was kept open during the latter half of May 2011 to prevent flooding in the urban Winnipeg area. That action eased pressure on downstream dikes, but raised the level of Lake Manitoba. Response agencies are using Landsat satellite data and field measurements to monitor water levels and the extent of water spreading downstream to help them decide how to control stream levels.

Flood control		 Left: June 18, 1990. Right: June 12, 2011. Lake Meredith is a reservoir formed by the Sanford Dam on the Canadian River in the Texas panhandle. Continuous drought has diminished water levels significantly in the past few years, leading to a record low in 2011. In each image, the lake is the black feature near the center. Light tones at the lower end of the lake indicate dry land and former shores. Bright green indicates healthy vegetation along the river beds and irrigated fields in the upper center of each image. The nearby industrial area (a petroleum plant and a carbon-processing plant) appears as a dark spot. The light blue tone further east is Borger, Texas.

Shrinking Lake Meredith		 Left: May 28, 2011. Right: August 20, 2011. The Brahmaputra River flows through braided channels in eastern India and Bangladesh. The rainy season in this part of the world typically begins in June, and the image from late August shows a transformed landscape. According to <i>The Times of India</i>, sudden swelling of the river’s tributaries inundated villages and left thousands homeless in the Indian state of Assam. Both images use a combination of visible and infrared light to increase contrast between water and land. Vegetation is green and clouds are pale blue-green. Water appears in varying shades of blue, and is silvery blue where sunlight reflects off the surface.

Flooding along the Brahmaputra River		 Left: September 7, 2011. Right: September 23, 2011. Extremely dry conditions have led to major fires in north-central Australia during the past year. In February, fires along the coast caused extensive damage and loss of life. More recently, dry conditions fed many fires in Australia’s least populated area, the Tanami Desert region, which is about the size of Texas and Iowa combined. Vegetation on its sand ridges and plains is limited largely to short grasses and shrubs. The September 7 satellite image shows scars (dark area) from previous fires. The September 23 image shows further scarring from active fires.

Fires scorch northern Australia		 Left: August 20, 1991. Right: August 27, 2011. Elephant Butte Reservoir is one of many bodies of water in the southwestern U.S. that have been diminished by prolonged drought. Created by a dam on the Rio Grande built in 1916, it is still the largest lake in New Mexico, but its water levels have declined over the past 20 years. In 2009, the Bureau of Reclamation established a plan to restore those levels through conservation measures. Although fossils of the stegomastodon (an ancestor of today’s elephant) were discovered nearby, the reservoir’s name actually stems from an island it contains — the eroded core of an ancient volcano — which is shaped like an elephant.

Elephant Butte Reservoir
Left: June 29, 1909. Right: September 4, 2000.

Toboggan Glacier, Alaska		 San Antonio, Texas. Left: June 16, 1991. Right: June 4, 2010. San Antonio has grown faster during the last two decades than all but three other cities in the U.S., nearly doubling from 790,000 people in 1991 to 1.4 million in 2010. Under state law, which allows the city to direct growth and zoning in much of the surrounding unincorporated land, San Antonio has opposed the creation of other nearby municipalities and has preserved agricultural production areas. A series of military bases and airfields, which ring the larger community, have also contributed to the city’s growth.

Growth of San Antonio, Texas		 Goksu River basin, southeastern Turkey. Left: July 11, 1987. Right: July 13, 2011. In 1990, a series of seven dams was started in the Goksu River basin to provide long-term hydroelectric power to the region. Government officials and others are using Landsat satellite data to monitor the growth and impact of these dams, since the Goksu is one of the few remaining free-flowing rivers in Turkey. The Gezende dam, completed in the early 1990s, reduced flow downstream and significantly affected aquatic species, while construction of the Ermenek dam in the early 2000s created a large reservoir that flooded fragile wildlife habitat.

Dams in the Goksu River basin, Turkey		 South-central Texas, U.S. Left: August 26, 2011. Right: September 11, 2011. The most destructive wildfires in Texas history raged near Bastrop State Park, 30 miles (48 kilometers) southeast of Austin. More than 1500 homes were destroyed and thousands of scorched acres are visible in the September image. Called the “Great Drought of 2011” by some, this year has seen the lowest single-year rainfall since the late 1800s and, as a result, many wildfires throughout the state.

Wildfire destruction		 Farmland in the Black Dirt region, New York. Left: July 30, 2011. Right: August 31, 2011. Flooding from Hurricane Irene, shown on the right, brought an early end to the region’s vegetable harvest. Located about an hour’s drive from New York City, farms in the area have provided onions and other vegetables for over a century. The area used to be the bottom of a shallow lake, resulting in rich organic soil, which can be seen as deep browns and reds in the images.

Flooding from Hurricane Irene
The Haiti-Dominican Republic border. Left: December 28, 1973. Right: January 22, 2010. From 1973 to 2010, Haiti lost a substantial amount of vegetation near its border with the Dominican Republic, while the Dominican side did not. Both countries depend on low-return agriculture on poor, badly irrigated soils. But Haiti is submerged in political, economic, and environmental crises without parallel in the hemisphere, setting it apart from its neighbor. The 2010 Haiti earthquake left over 300,000 people dead and over 1.5 million homeless, and a 2004 coup removed President Aristide, who was forced into exile by rebels with the help of U.S. and U.N. forces.

Haiti bares its border		 Victoria, Australia. Left: February 16, 2009. Right: January 5, 2011. A series of bushfires in early February 2009, during a record-breaking heat wave and extremely dry conditions, resulted in the largest loss of life from bushfires Australia has ever recorded. Some 400 individual fires were raging on February 7 alone, a day widely referred to as Black Sunday. The 2009 image shows fire scars and smoke; by 2011 regrowth can be seen. The city of Melbourne is visible in the lower left of each image.

Bouncing back from Black Sunday		 Gulf Coast, USA. Left: August 29, 2011. Right: September 6, 2011. Tropical Depression Lee made landfall here during Labor Day weekend, dumping up to 10 inches (25 centimeters) of rain in the bayou communities of Louisiana. The September 6 image shows the low-lying areas filled with water (shown in blue). The August 29 picture shows the area before the storm arrived. Subsequent imagery will be used to monitor recovery of the region.

No Labor Day picnic		 McCarty Glacier, Alaska. Left: July 30, 1909. Right: August 11, 2004.

Baked Alaska		 The Omo Delta, at the north end of Lake Turkana, a lake now located mainly in Kenya. Left: February 1, 1973. Right: January 24, 2005 to February 12, 2006. In 1973, the delta was contained entirely within the boundaries of Ethiopia. By 2005-2006, the southernmost point of the delta had moved roughly 12 kilometers (7 miles) to the south, and had crossed the Ethiopia-Kenya border. Reduced lake levels — from less rain, more diverted upstream water, and increased evaporation due to higher temperatures — are believed to be the primary cause, with an increase in sediment from agricultural activities also contributing. The expanded delta has provided new land for 20,000 Dassanech people, the area’s traditional inhabitants. But severe flooding in 2006 killed 100 of them and destroyed houses, crops and infrastructure.

Delta force
Holly Shelter Game Land, North Carolina. Left: June 19, 2011. Right: July 21, 2011. Lightning sparked a fire here on June 19 and hot, dry conditions helped fuel the fast ignition of over 21,000 acres of thick evergreen shrubs and flammable coal-like soil. The fire continued to burn as of August 30, according to the North Carolina Forest Service, and lingering drought hampered efforts to put out the blaze. The image on the right shows fire scars in brown, active fires in red, and smoke in light blue.

The peat goes on		 The Atacama Desert, Chile. Left: November 23, 1987. Right: June 25, 2009. Population has doubled here over the past two decades due to explosive tourist development in the 1990s and a mining boom in the 1980s, when companies began to extract lithium and other minerals from the Atacama Salt Flats. Today the mining, tourism, domestic and agricultural sectors compete for the region’s resources, and the main source of conflict is access to water. These images show the growth of mining operations from their beginning (white rectangle at lower right of the 1987 image) to a more recent level (purple and while rectangles in the 2009 image).

Mining their own business		 Left: August 1985. Right: August 2010. Iran’s Lake Oroumeih (also spelled Urmia) is the largest lake in the Middle East and the third largest saltwater lake on Earth. But dams on feeder streams, expanded use of ground water, and a decades-long drought have reduced it to 60 percent of the size it was in the 1980s. Light blue tones in the 2010 image represent shallow water and salt deposits. Increased salinity has led to an absence of fish and habitat for migratory waterfowl. At the current rate, the lake will be completely dry by the end of 2013.

Drying out		 Left: April 1, 1999. Right: February 13, 2011. Mundra Port is on the Gulf of Kutch on the west coast of India. These images illustrate its growth from inception to its status as India's largest private port. Over 60,000 workers maintain the facilities, which include the world's largest accommodations for coal handling. The port's location makes it a convenient international trade gateway to Europe, Africa, North America and the Middle East.

A passage to India		 Las Conchas, New Mexico. Left: June 24, 2011. Right: July 2, 2011. A major fire ripped through New Mexico, destroying sites considered sacred by American Indian tribes and threatening the Los Alamos National Nuclear Laboratory. The blaze, thought to have been started by a downed power line, burned more than 125,000 acres of the Santa Fe National Forest. In the July 2 image, burned areas are reddish brown and bright tones at the edge of the forest indicate active fires.

New Mexico ablaze
The Bay of Fundy, Nova Scotia, Canada. Left: High tide, April 20, 2001. Right: Low tide, September 30, 2002. The highest tides on Earth occur at the eastern extreme of the Bay of Fundy in Canada. Like a parent pushing a child on a swing, the Atlantic tidal pulse pushes the water at nearly the optimal frequency — given the configuration of the Bay of Fundy-Gulf of Maine basin — to cause large sloshing. When all factors are in phase, the difference between high and low tides can reach 16 meters (52 feet).

Time and tide		 Sabriyah Oil Field, Kuwait. Left: February 2, 1991. Right: July 15, 2011. Iraqi forces set hundreds of oil wells ablaze during the U.S.-led Gulf War following Iraq’s invasion of Kuwait in 1991. Some six million barrels of oil per day went up in smoke. Residue darkened the normally light-colored soil, as seen in the 1991 image. By 2011, the environment has largely recovered. Smoke plumes in the latter image are from fires normally set to burn off gases from the wells.

Oil well that ends well		 The Rio Grande river, U.S. Left: June 27, 2010. Right: July 13, 2010. Hurricane Alex was the first tropical cyclone to form in the 2010 Atlantic hurricane season. It weakened to a tropical storm when it made landfall in Mexico, but still dumped 25 to 50 centimeters (10 to 20 inches) of rain on the already saturated ground of the Rio Grande basin in southern Texas and northeastern Mexico in the first few days of July. People in low-lying areas on both sides of the border were evacuated as the river rose to more than 9 meters (30 feet) above flood level at Laredo.

Rio muy grande		 Dakhla Oasis, Egypt. Left: January 4, 1986. Right: January 14, 2010. Dakhla Oasis lies 300 kilometers (190 miles) west of the Nile. It is surrounded by the driest of desert landscapes, but beneath it lies the southern edge of the Post Nubian Aquifer. Use of water drawn from deep wells in the aquifer has increased tenfold since 1960, with a corresponding growth in agriculture. But some studies suggest that the planned rate of extraction is unsustainable and will lead to local depressions in the water table, making the precious liquid more and more expensive to access.

Oasis basis		 New Orleans. Left: September 7, 2005. Center: October 9, 2005. Right: September 2, 2009.In the September 2005 image, dark tones represent areas of New Orleans flooded by Hurricane Katrina, the costliest storm in U.S. history. Significant areas are seen to be drying in the October image, but light brown tones represent areas where vegetation (trees, lawns, parks) has been destroyed. By September 2009, brown tones are replaced by green, indicating new vegetation growth as neighborhoods rebuild. A portion of Lake Pontchartrain is visible at the top of the image.

Bringing back the Big Easy
Left: March 3, 1975. Right: January 15, 2010. Costa Rica’s Greater Metropolitan Area, which includes the San José Province and surrounding urban areas, is an area of concentration. It contains more than 50 percent of the country’s population, 70 percent of vehicles and 85 percent of the country’s industry in just 4 percent of the national territory. In the 1975 image, wooded areas separate urban centers. By 2010, the distinct cities have merged into a single unbroken urban expanse from which green areas have disappeared.

Urban sprawl in Costa Rica		 Warming Island, Greenland. Left: August 11, 1985. Center: September 5, 2002. Right: September 4, 2005. On January 16, 2007, the New York Times reported that a new island had been found in Greenland. Warming Island was thought to be an ice-covered peninsula, but it was exposed as an island in 2005, when an ice bridge melted to reveal an open-water strait. More islands like this may be discovered if the Greenland ice sheet continues to disappear.

Island of instability		 Lac (Lake) Péligre, Haiti's most important reservoir. Left: December 28, 1973. Right: January 22, 2010. Inadequate soil-conservation practices by small farmers along the upper part of the country's largest river, the Artibonité, are one of the main causes of watershed erosion and resultant buildup of sediment in the lake. Comparing the images from 1973 and 2010 reveals a drop in vegetative cover, narrowing of the Aritbonité's course in the Savane Perdue delta area, and an increase in sediment in the river’s water.

Sedimental journey		 Devils Lake, North Dakota. Left: August 31, 1991. Right: September 4, 2010. With no natural river or stream to carry away excess water, Devils Lake expands and contracts dramatically with the area’s variations in rain and snow melt. Along with smaller regional lakes, it has inundated farmland, roads, and buildings after heavy precipitation. Devils Lake, alone, has flooded more than 150,000 acres.

Dealing with the Devils		 Sudan. Left: April 17, 2005. Right: February 26, 2010. Merowe dam, on the Nile in north-central Sudan, is among Africa’s largest hydroelectric projects. It is expected to generate nearly 6000 GWh of much-needed electricity every year, and will have the potential to irrigate some 400,000 hectares of crops. However, the dam’s development has submerged substantial agricultural land and, according to reports, forced tens of thousands of people to relocate their homes and livelihoods, prompting complaints from the United Nations and non-governmental organizations.

Damming the Nile
Belize City, Belize. Left: December 27, 1989. Right: March 25, 2010. In the two decades separating these images, Belize City's population increased from 43,000 to more than 71,000, expanding westward largely at the expense of wetlands and mangrove swamps, and seaward with the use of landfill. The city's area in 2010 encompassed 14.1 square kilometers (5.4 square miles) — double its area in 1980.

Burgeoning Belize		 Rocky Mountain National Park, Colorado. Left: September 22, 2003. Right: September 25, 2010. Mountain Pine Beetles killed about 60 percent of the medium-to-large lodgepole pines on the western slopes of the park between the years depicted here. In the 2003 image, dense vegetation (dark green) is seen near the center. In the 2010 image, the dark green has been replaced by shades of brown over large areas, indicating tree loss.

Beetle-mania		 Minot, North Dakota. Left: May 16, 2011. Right: June 25, 2011. Heavy rain in Canada pushed the Souris River to overflow its banks here, flooding more than 4,000 homes and hundreds of businesses. About one-quarter of Minot’s 40,000 residents evacuated the city. The water level at Minot’s Broadway Bridge exceeded the previous record high set in 1881 by nearly 1.2 meters (4 feet).

Record flood in North Dakota		 The Kara-Bogaz-Gol basin on the eastern edge of the Caspian Sea. Left: December 4, 1972. Middle: September 25, 1987. Right: October 10, 2010. The basin’s water level has periodically undergone dramatic changes, and damming of its feeder inlets increased the magnitude of those changes. In 1980, a severe drop left a “salt bowl,” with windborne salt reportedly poisoning soil and causing health problems hundreds of kilometers to the east. In 1984, the basin dried up completely. In 1992, after the barrier was breached, sea level rose, remaining fairly stable from 2000 to 2010.

Sea-saw		 Libya. Left: January 13 to April 28, 1987. Right: March 25 to April 3, 2010. With among the least renewable water of the North African countries, Libya relies on groundwater to meet 95 per cent of its water needs. In the 1960s, the discovery of water in deep aquifers under Libya’s southern desert inspired an enormous water transfer scheme - the Great Man-Made River Project, one of the largest civil engineering enterprises in the world. These images show the increase in irrigation in the Murzuq Basin in southeastern Libya made possible by water drawn from the east and northeast Jabal Hasaouna well fields.

Water beneath the sands
Left: March 8, 2011. Right: April 25, 2011. On March 16, 2011, lightning in the drought-stricken Mexican state of Coahuila sparked two fires, which were so close to Texas that the U.S. provided assistance in suppressing them. The northwestern portion of the scene is in Texas, and the rest is Coahuila. Burned vegetation appears dark red in the April image.

Fires in Northern Mexico		 Lake Okeechobee, Florida. Left: June 19, 2000. Middle: January 19, 2003. Right: June 23, 2007. The second-largest freshwater lake wholly within the continental U.S. has been shrinking due to drought, agriculture and residential use. The water level in the 2007 image is about 2.7 meters (8.9 feet) high, which is about 1 meter (3 feet) below its historical average for that time of year. Reduction of the lake’s area is particularly evident in the west and southeast of the image.

Okey dokey Okeechobee?		 Bear Glacier, Alaska. Left: May 16, 1989. Right: May 26, 2010. In 1809, Bear Glacier was 26 kilometers (16 miles) long and ended about 300 meters (980 feet) from the shore of Resurrection Bay. Since then, the terminus has gradually melted and calved away icebergs. It took about 140 years for the glacier to retreat by 400 meters (1300 feet), but more recently the retreat has sped up substantially. It only took about 45 years (from 1950 to the mid-1990s) for the glacier to retreat by another 1.5 kilometers (0.9 miles). By 2010, some 15 years later, another 3 kilometers (1.9 miles) were gone.

Receding Bear-line		 Portland Bight Protected Area, Jamaica. Left: January 29, 1985. Right: January 18, 2010. Established in 1999, this is Jamaica's largest protected area, covering some 520 square kilometers (201 square miles) of land and 1400 square kilometers (540 square miles) of ocean. Land that had been in intensive use has regenerated since the 1980s, but some northern sections are giving way to the suburbs of Kingston Portmore.

Regenerating Jamaica		 Wax Lake Delta, Louisiana. Left: January 13, 1983. Right: January 2, 2011. The delta, where the Atchafalaya River flows into the Gulf of Mexico, was formed by sediment following the construction of a canal through Wax Lake in 1941. Since Hurricane Katrina in 2005, the delta has served as a model for restoring wildlife habitat and protection against storm surge in the Mississippi River delta region.

Delta defense
Senegal River Delta. Left: July 5, 2010. Right: September 15, 2010. The July image shows the region during a dry period; by September we can see flooding following late summer rains. Regional governments have taken measures to regulate the river flow, including installing upstream dams, which have lessened the impact of the rainy season on delta flooding and also provided hydroelectric power to the area. But the dams have affected a vital goods route to the ocean, and have greatly changed water quality (increased salinity and waterborne diseases) and the environment.

Dammed if you do, dammed if you don’t		 Xinjiang Uyghur Autonomous Region of Northwest China. Left: Sept. 3, 1989. Right: Sept. 21, 2010. "Green" cropland has spread in this area, north of the Borohoro Mountains / Tian Shan Range. Fertile land, low population density, few industrial and mining enterprises, and comparatively little pollution support environmentally friendly farming. The region's relative isolation allows crops to avoid disease and insects with minimal application of chemicals. Ürümqi, at lower right, is the largest city in China's western interior and the world’s most remote major city from any sea.

Green China		 Darién, Panama. Left: February 23, 1974. Right: March 28, 2000. Though considered one of the world’s most important conservation sites, the area has suffered massive deforestation, as seen in the 2000 image. Of the many threats facing the area, completion of the Pan-American Highway is the gravest, according to the United Nations Environment Programme. The highway runs from Alaska to Argentina, interrupted only in the “Darién Gap,” where it ends 50 kilometers (31 miles) from the Colombian border.

Closing the gap?		 Western Texas. Left: February 27, 2011. Right: April 16, 2011. Extreme drought and high winds fueled more than a dozen wildfires April 14 to 16, blazing across at least 400 square miles. The largest red area in the April 16 image is scarring from the Rock House fire, which scorched more than 120,000 acres and ravaged dozens of structures in and around the town of Fort Davis. Smoke from an active fire appears at the top of the scar.

Wildfires out west		 Petermann Glacier, Greenland. Left: June 26, 2010. Right: August 13, 2010. An iceberg more than four times the size of Manhattan broke off the Petermann Glacier (the curved, nearly vertical stripe stretching up from the bottom right of the images) along the northwestern coast of Greenland. Warmer water below the floating ice and at the sea’s surface were probably responsible for the break.

Cold snap
Chernobyl Nuclear Power Plant, 25 years after the meltdown. Left: April 29, 1986. Right: April 27, 2011. The 1986 image shows cultivated fields prepared for planting (bright, light tones), dense forest cover (dark green), and small communities (blue, purple). In the 2011 image, limited resettlement has begun. Most of the fields are now grasslands (light green), the dense forests have been destroyed and replanted (lighter, more uniform green), and the communities have been abandoned.

Chernobyl 2011		 Yellowstone National Park. Left: October 1988. Center: September 1993. Right: August 2007. Lightning strikes in June 1988 sparked wildfires that continued until November, burning 36 percent of the park. The October 1988 image shows deep red scars, but recovery, aided by nutrients from the ash, started as soon as spring returned. Wildflowers were abundant by mid-year. Vegetation including grasses and shrubs are displayed as a rich green in the 1993 and 2007 images.

Flourishing after the flames		 Mississippi River. Left: January 28, 2011. Right: May 8, 2011. These images show Tennessee and the state of Mississippi to the east of the river and Arkansas to the west. After one of the snowiest winters on record and several violent early-spring rainstorms, the Mississippi River and its tributaries overflowed their banks, inundating hundreds of thousands of acres of homes, cropland, and woodland with muddy water. The images use a combination of infrared and visible light; vegetation appears bright green, soil is brown, clouds are off-white to pale blue-green, and water varies from electric blue to navy.

Flooding devastates U.S. Midwest		 McCall Glacier, Alaska. Left: July 1958. Right: August 14, 2003.

Melting McCall		 Toshka, Egypt. Left: Sept. 13, 1984 to Sept. 29, 1987. Center: Aug. 23 to Sept. 1, 2000. Right: Mar. 21 to 28, 2010. In the mid-1990s, excess water was channeled from the Lake Nasser reservoir on the Nile River to the Toshka Depression in the Western Desert, creating a series of lakes. This "New Valley Project" was to relieve overcrowding within the Nile Valley and boost the economy. Despite soil poorly suited to irrigation, the area produced grapes, cantaloupes, tomatoes, cucumbers, citrus fruits and wheat. But Lake Nasser water levels fell after 1998 and flow to Toshka ceased in 2001. At the current rate of decline, the new lakes will be lost to evaporation within the next few years.

Egyptian lakes come and go
Santa Cruz, Bolivia. Left: June 17, 1975. Right: May 6, 2003. In 1975, the forest stretched from Rio San Pedro to the Rio Grande (Guapay) River. By 1986, roads linked the region to population centers, enabling a large influx of people. Forests were clear-cut and converted to pastures and cropland as part of the Tierras Baja project. By 2003, almost the entire region had been converted to agriculture, including the area east of La Esperanza across the Rio Grande.

A forest falls		 Queensland, Australia. Left: December 14, 2010. Right: January 4, 2011. Following a multi-year drought, unusually heavy La Niña rains caused massive flooding after the 2010 image was captured. The straight, well-defined channel through the city of Rockhampton indicates some measure of flood control, but north of the city, the Fitzroy River burst its banks and surrounded Rockhampton on the northwest. Similar flooding appears to be happening south of the city, but clouds (turquoise and white) obscure the view. Floods throughout Queensland, partially shown in the 2011 image, affected more than 200,000 people according to the Australian Broadcasting Corporation.

Flooding in Queensland, Australia		 Loita Plains, Kenya. Left: July 29, 1975. Right: December 16, 2007. The annual migration of the gnus, also known as wildebeests, is the primary tourist attraction of the Masai Mara National Reserve. The Loita Plains to the northeast have been the animals’ core breeding and calving grounds, as well as grazing land during the wet season. However, large mechanized wheat farms in the area surrounding Masai Mara expanded roughly tenfold between 1975 and 1995, mostly on the Loita Plains, reducing the natural grasslands on which the gnus depend.

Bad news for gnus		 Wadi As-Sirhan, Saudi Arabia. Left: February 2, 1986. Right: February 12, 2004. Once so barren it could barely support the towns of Al'Isawiyah and Tubarjal (upper left of each image), a vast desert region gradually blossomed into crop-producing fields (green dots) by use of center-pivot irrigation. The system used here draws from an ancient aquifer containing water as much as 20,000 years old. Judicious use of water resources and climate-appropriate technology has improved food production without harming the environment.

Desert bloom		 Holgate Glacier, Alaska. Left: July 24, 1909. Right: August 13, 2004.

The melting of Holgate Glacier
Guatemala-Mexico border. Left: February 14-15, 1974. Right: March 27-April 3, 2000. Most of the Guatemalan side remains closed canopy forest thanks in part to the protected status of the Sierra de Lacondon and Laguna del Tigre National Parks. On the Mexican side, much of the forest was converted to cropland or pasture between 1974 and 2000 in response to a larger and increasing population, creating a stark difference at the borderline.

Stark contrast		 Diawling National Park, Mauritania, Senegal. Left: September 30, 1979. Right: October 6, 2006. Wetland regions of Mauritania and Senegal were already suffering from drought before the Diama and Manantali dams were built in the 1980s to regulate the flow of the Senegal River and generate hydroelectric power. After construction, fish stocks decreased and wetland vegetation was decimated. Controlled flooding in the early 1990s revived the wetlands and restored much of the lost flora and fauna, as seen in the 2006 picture.

Reviving African wetlands		 Left: Detail from mosaic of images taken May 24, July 2 and July 4, 2010. Right: Detail of mosaic of images taken August 12, 19 and 21, 2010. The image at left shows the Indus River in Pakistan before what United Nations relief teams called "one of the worst humanitarian disasters in history." The right-hand image shows the river overflowing its banks as a result of historic monsoon rains. More than a million acres were flooded, destroying crops and devastating cities including Sukkar, Mehar, and Dadu. The number of people directly affected exceeded 21 million, including 1,800 killed and 10 million left without shelter.

Indus River Valley inundated		 Lake Chad, Africa. Left: December. 8, 1972. Middle: December 14, 1987. Right: December. 18, 2002. Persistent drought has shrunk Lake Chad, once the world’s sixth largest lake, to about one-twentieth of the size it was in the 1960s. Only 16 to 26 feet (5 to 8 meters) deep in

Shrinking Lake Chad		 Left: August 1906. Right: June 21, 2004.

Retreat of Carroll Glacier, Alaska
Near Santa Cruz de la Sierra, Bolivia. Left: August 4, 1986. Right: August 11, 2001. Most of the tropical dry forest visible in the 1986 image (dark red) has been replaced in the 2001 image by resettlement of people from the Altiplano (the Andean high plains) and by soybean production. The radial patterns are part of the San Javier resettlement plan. At the center of each unit is a small community that includes a church, bar/cafe, school and soccer field. The rectangular, light-colored areas are fields of soybeans cultivated for export. The dark strips running through the fields are windbreaks to protect the soil, which is prone to wind erosion.

Felling a forest for settlers and soybeans		 Left: August 2008. Right: March 14, 2011. Close inspection of the post-tsunami image on the right reveals that vegetation (shown in red) is no longer present in many coastal areas, particularly around Kesennuma, a city of about 73,000. Kesennuma and Ofunato are about 90 kilometers (55 miles) northeast of Sendai. The magnitude 9.0 earthquake on March 11, 2011, which triggered the tsunami, was centered offshore about 130 kilometers (80 miles) east of Sendai.

Tsunami aftermath near Ofunato and Kesennuma, Japan		 Flooding in and near Ishinomake, Japan, three days after a massive tsunami was triggered by a magnitude 9.0 earthquake. Left: August 8, 2008. Right: March 14, 2011. In these false-color images, water is dark blue, plant-covered land is red, exposed earth is tan, and the dry city is silver. The image on the left shows the area almost three years before the tsunami. In the image at right, standing water is most evident in the former fields. The most extensive flooding is around the Matsushima Air Base in the lower left, but dark blue within the city indicates that these areas are probably flooded as well.

Tsunami damage near Ishinomake, Japan		 Japanese coastline near the city of Sendai. Left: February 26, 2011. Right: March 13, 2011. The image on the right reveals extensive flooding two days after a powerful tsunami swept ashore, caused by the magnitude 9.0 earthquake that devastated northeastern Japan on March 11, 2011. Water still covers the ground more than 4 kilometers (2.5 miles) from the coast. The image on the left shows the coastline weeks before the tsunami struck.

Tsunami flooding near Sendai, Japan		 Coastal flooding near the city of Sendai, Japan, a day after a deadly earthquake and tsunami hit the country. Left: March 16, 2001. Right: March 12, 2011 at 10:30 a.m. local time. Water extends more than 4 kilometers (2.5 miles) inland from the eastern shoreline in the image on the right, the result of a massive tsunami that was triggered by a magnitude 9.0 earthquake centered off Japan’s northeastern coast, some 130 km (82 miles) east of Sendai. White sand beaches visible in the image on the left — taken about 10 years ago under nearly identical lighting conditions — are covered by water in the post-tsunami image.

The morning after Japan's tsunami
Imja Glacier in the Himalayas, as seen from a point above Amphu Lake and from the upper slopes of Island Peak. Left: Autumn, circa 1956. Right: October 18, 2007. The latter image shows pronounced retreat and collapse of the lower tongue of the glacier and the formation of new melt ponds.

Imja Glacier, Himalayas		 The Yellow River Delta in China. Left: 2001. Right: 2009. The Yellow River is the second-longest river in China, and the sixth-longest in the world. It has been the cradle of Chinese civilization; but frequent devastating floods have also earned it the name of "China's Sorrow." Historical maps tell us that the river has undergone many dramatic changes in its course. Currently, the Yellow River ends in the Bohai Sea, yet its eastern terminus continues to oscillate from points north and south of the Shandong Peninsula. These images show the changes.

The Yellow River Delta, China

Bear Glacier, Alaska, then and now

Greener pastures, Australia

Okpilak Glacier, Alaska


Retreat of Greenland’s Helheim Glacier

A century of warming

Dirty skies, Mexico City

Landslide lake, Tibet

The expansion of Riyadh


New Orleans after Katrina

Slippery slope, Colorado

Mount Kilimanjaro, Africa

Less is Muir

Flooding in Gonaïves, Haiti


Wetland woes

Drought in the Black Hills, South Dakota		 Images taken by the NASA/USGS Landsat satellite. Courtesy Jim Williams, NASA GSFC Scientific Visualization Studio, and the Landsat 7 Science Team.

Giddy heights, Africa

Addis Ababa, Ethiopia

And the waters came: Pakistan


Washed away

The need for Mead

Hot rock

Mixing waters and moving ships

Crikey! It's Hurricane Ike


Then and now

Time travel

Blast from Boston's past

In it for the long run

Awesome Doldenhorn


Dunes of Iran

Dongting Lake, China

Avian rest stop

The life and times of Jakarta

Imja image


'Tis the season

Icelandic rumblings		 The Mato Grosso state in southwest Brazil. Left: 1992. Right: 2006. In the Brazilian Amazon, deforestation has been proceeding at a rate of about 20,000 square kilometers per year, and Mato Grosso state is no exception. The left image is a 1992 Landsat Thematic Mapper image. About 25 percent of the area has been clear-cut for pastures and farms. In 2006, the ASTER image shows over 80 percent of the rainforest gone, cleared for pastureland by commercial and speculative interests, and poorly planned government policies.

Mato Grosso, Brazil

Mother's necklace, Himalayas		 Images taken by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Terra satellite. Credit: <A href='http://earthobservatory.nasa.gov/IOTD/view.php?id=8723' target='_blank'>NASA's Earth Observatory</A>.

Burma bombarded


The march of deforestation

Pedersen past and present

Tsunami strikes		 Credit: Images taken by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Terra satellite. Courtesy of NASA's Earth Observatory.

Aral gone awry

Mighty Matterhorn


Turbulent times

Dusty day

Peru view

Oil expedition

Carbon counter


Las Vegas boom

The shrinking Puncak Jaya
 
 
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