Rainforests get swallowed by farms in Brazil

(<a href="http://climate.nasa.gov/state_of_flux#Deforestation_Brazil1.jpg">NASA, Images of Change</a>)

Satellite images of Rondônia in Western Brazil, taken in 1975 (left) and 2009 (right). (NASA, Images of Change)

Humans have been clearing forests to make way for farms and pastures for at least 7,000 years. And as the world’s population soars past 7 billion, the pressure for cropland is only growing.

 

 Cancún expands at a stunning rate

(NASA, Images of Change)

Cancún, Mexico, seen in 1979 and 2009. (NASA, Images of Change)

Cities and towns have been around for thousands of years, but the growth of urbanization has been astonishing over the past century. More than 3.9 billion peopleand counting now live in urban areas.

The images above show the rapid growth of Cancún, Mexico. In the 1970s, this area was lightly inhabited, home to artisanal fishermen and empty beaches

Dubai builds a chain of artificial islands

(U.S. Department of the Interior / USGS and NASA)

Dubai, United Arab Emirates, seen in 2001 and 2011. (USGS and NASA)

Some cities have gotten creative about urban growth, reclaiming land from the sea. These images show the rapid growth of Dubai, in the United Arab Emirates, between 2000 and 2011.

 

Efforts to tame the Colorado River hit a snag

(<a href="http://climate.nasa.gov/state_of_flux#Lakepowell_930x544.jpg">NASA, Images of Change</a>)

Lake Powell, seen on March 25, 1999, and May 13, 2014. (NASA, Images of Change)

The Colorado River begins in the Rocky Mountains and courses through the American Southwest. During the 20th century, Americans built a complex system of dams and reservoirs to tame the river, providing a steady source of freshwater for farms and cities like Phoenix and Las Vegas. Water from the river is divvied up among states under an elaborate set of rules.

 

The Aral Sea, once massive, nearly vanishes

The Aral Sea, seen in 2000 and 2014. (NASA, Images of Change)

The Aral Sea, tucked between Kazakhstan and Uzbekistan, was once the fourth-largest lake in the world. Today, after decades of being drained for irrigation, it’s nearly gone.

 

Alaska’s Columbia Glacier recedes rapidly

(<a href="http://climate.nasa.gov/state_of_flux#Columbia_Glacier_930x312.jpg">NASA, Images of Change</a>)

Alaska’s Columbia Glacier, seen on July 28, 1986 and July 2, 2014. (NASA, Images of Change)

One of the most dramatic ways we’re transforming the planet is through global warming. And a great place to see its effects is through the melting of glaciers and ice sheetsaround the world.

 

Antarctica’s Larsen B ice shelf disintegrates

Larsen-B ice shelf in Antarctica, seen on January 31, 2002 and February 17, 2002. (NASA, World of Change)

Receding glaciers are one thing. But the massive ice sheets atop Greenland and Antarctica are an even bigger deal. As the world keeps warming, these ice sheets are starting to melt into the ocean, a change that is expected to raise global sea levels significantly.

 

The US cleans up its air pollution

Images show concentrations of nitrogen dioxide in 2005 and 2011, from low (blue) to high (red) (NASA, Images of Change)

Not all of the ways we’re transforming the planet are negative. Here’s some good news: Satellite data from NASA, shown above, revealed a huge reduction in nitrogen dioxide pollution from cars, trucks, power plants, in the United States between 2005 and 2011.

 

Iraq’s marshes recover after Saddam Hussein

The wetlands of Mesopotamia in 2000 and 2006. The map shows standing irrigated crops (light green), standing water (dark blue), vegetation (dark green), and bare ground (brown). (NASA, World of Change)

Here’s a change that actually restored nature — at least temporarily. During the 20th century, Iraq’s lush wetlands between the Tigris and Euphrates rivers had mostly dried up because of a series of dams that had been constructed for electricity, as well as a deliberate strategy by Saddam Hussein to drain the wetlands and punish the region’s Marsh Arabs for rebelling.

 

The ozone layer thins — but then starts healing

(NASA Earth Observatory)

(NASA Earth Observatory)

Sometimes it’s possible to stop an environmental catastrophe before it’s too late. Back in the 1970s, scientists first realized that we were rapidly depleting Earth’s stratospheric ozone layer, which protects us from the sun’s harmful ultraviolet rays. The culprit? Chlorofluorocarbons (CFCs) — chemicals that were widely used in refrigerators and air conditioners.