Singing the Icy Blues
Many of our favorite winter sports depend on snow. But did you know that Landsat monitors the snow that helps fill lakes & form ice sheets?
Over Troubled Water
We can also see the dramatic change in water levels over four decades. The lake is valuable to the local economy from brine shrimp, salt harvesting operations, magnesium mining, and recreation. The lake’s shallow waters also sustain millions of migratory birds.
The lake is fed by rain and freshwater rivers, but it also relies heavily on snow. Snow melts slowly into the ground and fills aquifers that fed into the lake. The image on the left shows the highest recorded level in 1985.
Over the past 4 decades, there has been less and less precipitation falling as snow. A sign of a changing climate. Demand for water also increased. More water was diverted to agriculture and housing to support the growing population in the Salt Lake City area. The Landsat image on the right shows the lake near record low levels.
Meltdown
Melt ponds are areas where snow has melted and pooled in low spots on glaciers and sea ice. The Landsat series of satellites has been tracking changes in glaciers and frozen lakes over time due to climate change and gives us a up-close look at these beautiful blue features.
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Widespread Melt on the George VI Ice Shelf
Warming temperatures in Antarctica have caused jewel-toned ponds of meltwater on top the George VI ice shelf. This melt event in January 2020 spans the length of the shelf, about 90 miles.
Darker blue color means deeper water. If lakes grow large enough, they can force open crevasses in the ice. The water then drains from the pond to the bottom of the ice sheet via chutes through the ice called moulins.
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Shades of Blue on the Greenland Ice Sheet
Melt ponds can store a lot of water and that water can also drain very fast. In April 2008, a team of scientists reported that most of the meltwater in a lake more than two miles long and 40 feet deep drained in less than 90 minutes in a cascade larger than the Niagara Falls! The drained water can also help the glacier slide toward the sea.
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Antarctica Melts Under Its Hottest Days on Record
During the warming event in 2020, the snowpack on Eagle Island on the Antarctic Peninsula melted 4 inches (106 millimeters) from February 4- February 13. The exposed bare ground and formation of light blue melt ponds reveal about 20 percent of seasonal snowfall melted in a week.
Slip Sliding Away
These images combine shortwave-infrared, near-infrared, and green light. This combination of Landsat bands show the snow and ice as bright cyan, vegetation is green, clouds are white or light orange, and open water is dark blue.
From 1986 to 2019, the nose (or terminus) of the glacier has retreated more than 20 kilometers. The increasing amount of brown bedrock indicates the glacier is also thinning.
Landsat’s half century of data provides a record of how glaciers are changing all over the world.
With a Little Help From Landsat
Ice from glaciers constantly flows into the ocean, but the speed the ice moves at changes. Scientists with the Global Landsat Ice Velocity Extraction (GoLIVE) project use Landsat to provide near-real-time mapping of ice speed around the globe. Information about how fast ice is melting into the seas helps scientists study changes impacting our planet such as sea level rise.
Landsat's Global View of Ice Velocity
These two images show the speed at which Greenland’s Heimdal Glacier is moving. In June 2016, the glacier was moving fast. Then in June, the beginning of Antarctica’s winter, the glacier slowed down until reaching its slowest point in early October.
Postcards from Camp Landsat
This week we visit Norway’s ice-covered archipelago halfway between Norway’s mainland and the North Pole. Exceptionally warm air temperatures in summer 2022 have caused record melting across Svalbard. The abundant meltwater, much of which flowed to the ocean, is the latest expression of a rapidly warming climate.
Collect all five postcards from Camp Landsat ending with Week 5: Ice & Climate !
The adventure continues at Camp Landsat with lots of fun and fascinating Landsat facts and activities.
