Satellites can offer some of the most compelling – and useful – imagery after a natural disaster hits.
Satellite imagery company DigitalGlobe shared these images, starting with that of the Dharahara Tower in Kathmandu, Nepal. This image was taken in October 2014, before an earthquake destroyed much of the region the following April. The tower is visible in the center.
After the Nepal earthquake toppled the 183-year-old tower, a DigitalGlobe satellite captured this image.
"A particularly poignant part of this imagery is that you can see so many people outdoors now," says DigitalGlobe's Kevin Bullock. "It's an indication of people being so scared to be in their homes that they would rather be in the streets."
After the quake, a refugee tent city popped up. Satellite imagery companies such as DigitalGlobe use these images to estimate how many displaced people may be in a given area, allowing disaster volunteers to better plan their relief efforts.
DigitalGlobe's image collection documents the changing landscape of billions of square kilometers. Example: the devastation that hit Seaside Heights, N.J., in 2012. This image was taken in 2011, before Hurricane Sandy hit.
The Outer Banks area of far eastern North Carolina sits between the Atlantic Ocean and a sound. The strip of land between the bodies of water is vulnerable to hurricanes and other severe weather. This is a section of the Outer Banks before a 2011 storm struck.
Satellites can capture various wavelengths of light, including those not visible to humans. The satellite that captured this pre-eruption Mt. Sinabung volcano, in Indonesia, collects images in several spectral bands, including infrared.
The red portions of this image are, in reality, green forest.
This DigitalGlobe image shows just how devastating, but compact, a tornado can be. The scar of the tornado is clearly visible, running from southwest to northeast across the image. The tornado, at its largest, was 1.5 miles wide.
The storm wiped out many of the city's waterside structures, including homes. By estimating an average of 3-4 people per hut, satellite imaging companies can help calculate the size and scope of a disaster more quickly than via headcount.
Note that the fishing boats–a main source of income for residents here–are gone.