NASA's Earth Observatory has collected a vast array of images and videos which demonstrate the effects of large scale human activity on the Earth as compiled in Wired Science.
The first example shows the building of a number of artificial islands in the shape of a palm tree off the coast of Dubai of the United Arab Emirates. The massive amounts of sand used for the project were dredged sand from the sea floor.
The Aral Sea in Central Asia, at one time the world's fourth largest lake has shrunken to 1/10th of its original size in the half century period from the 1960s to the present.The result is now three separate, highly salinic, lakes.
For more than thirty years, the state of Rondônia in western Brazil cleared almost 35 percent of its rainforest.The NASA time lapsed video shows roads first being built with land cleared for small farms. Erosion becomes a problem that soon results in "low crop yields" and consequently pushes farmers to introduce cattle as the clearing, farming, land depletion, cattle raising process continues as larger swaths of land are deforested.
Marshlands in Iraq that had been drained in the 1990s have recently been re-flooded and consequently has initiated a rerowth of vegetation.The difficulty associated with the re-introduction of water and subsequent egrowth of marshlands has been the issue of whether the marshes will survive for long since population expansion and their attendent water needs may cause the marshes to soon wither away.
The once robust Lake Powell in Sothern Utah was once a very popular recreational resource that has suffered a devastating drought "from 2000 to 2005" when "its water level dropped from 20 million to 8 million acre-feet."Climatologists have witnessed a slight uptick in water levels but are concerned that a future drought could have a devastating impact that completely dries up Lake Powell.
Sources:
NASA Earth Observatory
Wired Science at Wired .com
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