WASHINGTON: Next month, NASA will launch the most advanced laser instrument of its kind in space to measure the changes in the heights of the Earth's polar ice in unprecedented detail.
The Ice, Cloud and Land Elevation Satellite-2 (ICESat-2) will measure the average annual elevation change of land ice covering Greenland and Antarctica to the width of a pencil and capture 60,000 measurements per second.
"ICESat-2's new observation technologies – a top scientific community recommendation in the first Nasa geography test – will advance our understanding of how the ice sheets of Greenland and the Antarctic contribute to sea-level rise," said Michael Freilich NASA's Science Mission Directorate in the US.
2, represents a significant technological leap forward in our ability to measure ice height changes.
The Altitude Advanced Altitude System (ATLAS) measures altitude by determining how long individual photons of light will take to travel from spacecraft to Earth and back.
"ATLAS required us to develop new technologies to obtain the measurements scientists need to drive research," said Doug McLennan, ICESat-2 project manager at NASA's Goddard Space Flight Center.
"That meant we needed to develop a satellite instrument that not only collected incredibly accurate data, but also collected more than 250 times more height measurements than its predecessor," said McLennan.
ATLAS will fire 10,000 times a second and send hundreds of trillions of photons in six green rays to the ground.
The circulation of individual laser photons from ICESat-2 to the Earth's surface and back is precisely tuned to a billionth of a second to accurately measure heights.
As ICESat-2 orbits the earth from pole to pole, it will measure ice altitudes four times a year along the same path in the polar regions, enabling seasonal and annual monitoring of ice height changes.
Beyond the poles, ICESat-2 measures the height of the sea and land surfaces, including the forests.
ATLAS was developed to measure both the tops of the trees and the underlying soil, which, along with the existing records on forest extension, will help researchers estimate the amount of carbon stored in the world's forests.
Researchers will also study elevation data collected on ocean waves, reservoir levels, and urban areas.
"Because ICESat-2 will deliver measurements of unprecedented precision with global coverage, it will not only give new insights into the polar regions, but also unexpected results around the world," said Thorsten Markus, an ICESat-2 project scientist Goddard.