NASA’s High-Flying Laser Altimeter Measures Summer Sea Ice
- Wednesday, 16 July 2014
When NASA launches the Ice, Cloud and land Elevation Satellite-2, or ICESat-2, in 2017, it will measure Earth’s elevation by sending out pulses of green laser light and timing how long it takes individual photons to bounce off Earth’s surface and return. The number and patterns of photons that come back depend on the type of ice they bounce off – whether it’s smooth or rough, watery or snow-covered.
To get a preview of what summertime will look like to ICESat-2, NASA scientists, engineers, and pilots have traveled to Fairbanks, Alaska, to fly an airborne test bed instrument called the Multiple Altimeter Beam Experimental Lidar, or MABEL. MABEL collects data in the same way that ICESat-2’s instrument will – with lasers and photon-detectors. The data from the Alaskan campaign will allow researchers to develop computer programs, or algorithms, to analyze the information from ICESat-2.
“We need to give scientists data to enable them to develop algorithms that work during summer,” said Thorsten Markus, ICESat-2’s project scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “All the algorithms need to be tested and in place by the time of launch. And one thing that was missing was ICESat-2-like data on the summer conditions.”
Between July 12 and August 1, MABEL will fly aboard NASA’s high-altitude ER-2 aircraft as the Arctic sea ice and glaciers are melting. In its half-dozen flights, the instrument will take measurements of the sea ice and Alaska’s southern glaciers, as well as forests, lakes, open ocean, the atmosphere and more, sending data back to researchers on the ground.
Also: Learn about the Debris & ICE Mapping Analysis Tool (DIMAT).