Exit Glacier, photographed on May 23, 2014. Image: Nelson, Scot, From the Glacier Photograph Collection. Boulder, Colorado USA: National Snow and Ice Data Center.

A Glacier Recedes

In Alaska’s Kenai Fjords National Park, just outside of the town of Seward, the Exit Glacier is shrinking.

In the spring and summer months, glacial melt drains from the inland glacier’s ablation zone, flooding access roads and hiking trails. Here’s what the glacier looks like from above:

Exit Glacier imaged by a RapidEye satellite on September 10, 2010.

From the ground we can see evidence of the retreat over just one year. Emily Baker of the National Park Service documented the glacier in the calving process. Take a look at these images captured in August 2016, just fifteen days apart:

Left: image captured August 16, 2016. Right: Image captured August 31, 2016. Images: Emily Baker/National Park Service

From the ground we see chunks of ice that have calved, and an increase in glacial runoff and melt. The changes are even more striking if we lengthen our time axis, and observe the glacier from above.

Planet’s RapidEye satellites have been observing Exit Glacier for years.

Exit Glacier retreats over 6 years. Images captured by RapidEyes satellites on Sep 10, 2010; Sep 12, 2012; Aug 25, 2013; Aug 2, 2014; Aug 4 2015; and Sep 2, 2016.

From orbit, we can observe that the glacier has not only receded, but thinned along the edges as well.

Planet’s satellites collect imagery in a consistent, sun-synchronous orbit, creating a calibrated dataset from which the human eye or computer algorithms can spot the isolated incidents of day-to-day change, or track subtle, long-term trends.

As more of our satellites enter orbit, Planet is closer to being able to image the Earth’s entire land surface, every day. This will help to extend the long-term records of glaciers developed from existing satellites, and enable new types of near-real time monitoring and research into the dynamics of moving ice.

If you’re a researcher and would like access to Planet’s growing imagery dataset, visit planet.com/impact.