Images show annual variations in Arctic ice, drought conditions in Australia and the decline of the Aral Sea, among others.
As part of its 10-year anniversary, NASA’s Earth Observatory has compiled a gallery of images showing annual changes in the Earth’s land, water and atmosphere in places such as Central Asia, Australia, Iraq and the Amazon.
Photos of the Aral Sea reveal the near-complete evaporation of what was once the world’s fourth-largest inland water body. The southern section of the sea is now a slim finger of water at the western margin of its former boundary.
A dike built in 2005 cut off the flow of water between the two sections, saving the northern part, but dooming the southern. The Amu Darya River used to flow into the southern section, but its entire flow is diverted before it can reach the sea.
A different kind of dry appears in the satellite images of Australia. The photo series shows how the decade-long drought has affected vegetation in the southeastern states of Victoria and New South Wales. Above-average growing conditions in the early 2000s have given way to large areas of brown in agricultural areas along the River Murray.
NASA satellites also captured land use changes in Iraq and the Amazon.
The marshes of southern Iraq where the Tigris and Euphrates meet were once a lush area of biodiversity. Engineering projects built upstream in the latter half of the twentieth-century caused the marshes to shrink. In the 1990s Saddam Hussein drained the marshes to punish the people living there for taking part in a rebellion.
Images show dramatic improvement in the region, however, after the U.S. invasion in 2003. The marshes were flooded to restore the ecosystem. Even though 2009 was a dry year, images from the middle years of the decade show the wetlands returning to health. A United Nations Environmental Program study in 2006 concluded that 58 percent of the marshes had been restored.
But restoration is not the case in the Amazon. Satellite photos show the patterns of deforestation in the Brazilian state of Rondonia. Illegal roads provide an artery into the forest. Farmers clear lands on either side of the road, creating a “fishbone” pattern. When the land becomes too degraded for farming, the crops are cleared for cattle grazing.
Source: NASA Earth Observatory