From the ice sheets of Greenland to the deserts of Arizona, many of the world’s landscapes have been dramatically transformed as their climate grows warmer and drier. At the same time, water use and other human activities have altered many landscapes. NASA has accumulated striking photos that show just how much our surroundings have changed. Slide across each image to see before and after pictures.
A Shrinking Sea
The Aral Sea was once the fourth largest lake in the world. Progressively arid conditions and increased irrigation have decimated the lake and the surrounding communities that depend on it. Last year, the eastern basin dried completely.
August 25, 2000 August 19, 2014
SOURCE: NASA EARTH OBSERVATORY
Diminished Snowfall
Snowpack in California’s Sierra Nevada reached the lowest level in recorded history. In response to several years of drought, the state mandated water restrictions for the first time. California reservoirs depend heavily on annual snowmelt to meet its water demands.
March 2010 March 2015
SOURCE: JESSE ALLEN, NASA EARTH OBSERVATORY
Reservoir at Risk
Lake Mead, which depends on snowmelt from the Rockies, has seen its water levels plummet due to drought and increased demand. The lake’s elevation has dropped by 120 feet, putting the Las Vegas Valley at risk because it depends on the reservoir for 90 percent of its water.
July 6, 2000 July 24, 2015
SOURCE: JOSHUA STEVENS, NASA EARTH OBSERVATORY
Glacier’s Retreat
Yosemite National Park’s Lyell Glacier has receded tremendously over the last century, exposing swaths of bedrock underneath. Because of their sensitivity to the environment, glaciers are vital barometers of climate change.
SOURCE: ISRAEL RUSSELL, USGS; KEENAN TAKAHASHI, NPS
Choked by Drought
Decreased snowmelt from the Rockies severely reduced water levels in Arizona’s Lake Powell, affecting those who depend on it for water. Periodic droughts have become steadily more common. This year, the reservoirs were only at 45 percent capacity.
March 1999 April 2015. SOURCE: NASA EARTH OBSERVATORY
Breaking the Ice
The retreat of the Zachariæ Isstrøm glacier in Greenland has accelerated since 2012, dumping tons more ice into the Northern Atlantic every year. Experts fear the swift rate of the melting will have a tremendous impact on rising sea levels.
August 1999 August 2015
SOURCE: JESSE ALLEN, NASA EARTH OBSERVATORY
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Watch the full documentary 'Before The Flood' from 30th October 7.30pm AEDT here online: http://www.nationalgeographic.com.au/tv/before-the-flood/
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