Images of Change
Our planet is constantly changing, and we use the vantage point of space to increase our understanding of Earth, improve lives and safeguard our future.
These images show change over time, with periods ranging from centuries to years. 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. Take a look…
Urban Expansion in New Delhi, India
Between the times these two images were taken, the population of India’s capital and its suburbs (known collectively as “Delhi”) ballooned from 9.4 million to 25 million. It is now second in population only to Tokyo, which has 38 million people.
Great Salt Lake Shrinkage, Utah
Dramatic change in the area of the Great Salt Lake over the past 25 years. 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.
Exceptional Early Ice Melt, Greenland
Meltwater streams, rivers and lakes form in the surface of the Greenland Ice Sheet every spring or early summer, but melting began exceptionally early in 2016. Melting encourages further melting when pods of meltwater develop, since they darken the surface and absorb more sunlight than ice does. Surface melt contributes to sea-level rise when the water runs off into the ocean.
Iran’s Lake Urmia Changes Color
Some combination of algae and bacteria is periodically turning Iran’s Lake Urmia from green to red. The change typically occurs when summer heat and dryness evaporate water, increasing the lake’s saltiness. Data from satellites indicate that the lake has lost about 70% of its surface area over the last 14 years.
Owens Lake Degradation, California
Owens Lake lies in the Owens Valley between the Sierra Nevada and the 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.
Baban Rafi Deforestation, Niger
Baban Rafi Forest is the most significant area of woodland in the Maradi Department of Niger, a west African country on the southern edge of the Sahara Desert. These pictures show the loss of a significant fraction of the natural landscape (darker green areas) of the forest to agriculture. Population in this region quadrupled during the 40 years leading up to the 2007 image.
Colorado River Evolution, Mexico
These two pictures illustrate the extremes of water flow in the Colorado River since measurements began in the late 1800s. The 1985 image was taken in the midst of record high flow, while the 2007 image shows the driest period. Excessive rains or severe droughts directly change the amount of water available in the Colorado River Basin, and so does the increasing pressure of human needs throughout the western states.
Helheim Glacier Melt, Greenland
Along the margin of the Greenland Ice Sheet, outlet glaciers flow as icy rivers through fjords and out to sea. These pictures show a fjord in which Helheim Glacier (on the left) is crumbling into large and small icebergs (light blue, on the right). The glacier outlet held steady from the 1970s until about 2001, then began to retreat toward its source about 4/7 miles between 2001 and 2005. The glacier’s flow to the sea has also sped up.
Drying Lake Poopó, Bolivia
Lake Poopó, Bolivia’s second-largest lake and an important fishing resource for local communities, has dried up once again because of a drought and diversion of water sources for mining and agriculture. The last time it dried was in 1994, after which it took several years for water to return and even longer for ecosystems to recover.
Flooding on the Ganges River, India
Heavy monsoon rains have caused catastrophic flooding along the Ganges and other rivers in eastern and central India. At least 300 people died and more than six million were affected by the flooding, according to news reports. These images show a stretch of the Ganges near Patna.
All of this knowledge about our home planet enables policy makers, government agencies and other stakeholders to make informed decisions on critical issues that occur all around the world. From rising sea levels to the changing availability of freshwater, we enable studies that unravel the complexities of our planet from the highest reaches of Earth’s atmosphere to its core.
To see the full ‘Images of Change’ gallery, visit: http://climate.nasa.gov/images-of-change
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