Earth

New Calculations of Worldwide Glacial Flows and Volumes From Over 800,000 Pairs of Satellite Images

Ice Flow Velocities for Andean Glaciers

Ice flow velocities for Andean glaciers. Credit: © Romain Millan, Jean-Baptiste Barré / CNRS / IGE – Map data : Mapbox / OpenStreetMap / Maxar

Many mountain populations—in the Andes or Himalayas, for example—rely on glaciers for their water. Yet changes in glacial water reserves, like predictions of sea level rise, greatly depend on glacier volume and thickness, both of which have been poorly evaluated—until now.

By analyzing over 800,000 pairs of satellite images, researchers from the CNRS, Université Grenoble Alpes (France), and Dartmouth College (USA) have established the first global map of flow velocities for 98% (>200,000) of the world’s glaciers. As glacial flow is a function of glacial mass, knowing the former allows one to estimate ice thickness and spatial distribution, which in turn determine the total volume of water that glaciers hold and their future contribution to sea level rise.

Ice flow velocities for Alaskan glaciers. Credit: © Romain Millan, Jean-Baptiste Barré / CNRS / IGE – Map data : Mapbox / OpenStreetMap / Maxar

The researchers’ findings suggest glacial water reserves in the Himalayan watersheds of the Indus and Chenab are a third greater than estimated by previous studies, before the new satellite data were available. In contrast, the volume of water held in tropical Andean glaciers, which sustains over 4 million people, may be up to 23% smaller than once thought.

The present study, published in Nature Geoscience on February 7th, 2022, is based on Sentinel (ESA) and Landsat (NASA) satellite imagery that was analyzed on Université Grenoble Alpes servers (>106 h of computer processing time). It had support from the French space agency (CNES).

For more on this research, see New Atlas of Globe’s Glaciers Finds They Have Less Ice Than Previously Thought.

Reference: “Ice velocity and thickness of the world’s glaciers” by Romain Millan, Jérémie Mouginot, Antoine Rabatel and Mathieu Morlighem, 7 February 2022, Nature Geoscience.
DOI: 10.1038/s41561-021-00885-z

Share
By
CNRS

Recent Posts

Caltech’s Breakthrough New Nanophotonic Chip “Squeezes” More Out of Light

Electronic computing and communications have advanced significantly since the days of radio telegraphy and vacuum…

October 4, 2022

Parallels to HIV: Another Fatal Monkey Virus Could Be Poised for Spillover to Humans

Evoking parallels to HIV, authors are calling on global health community to be vigilant. According…

October 4, 2022

Scientists Show Transmission of Epigenetic Memory Across Multiple Generations

Changing the epigenetic marks on chromosomes results in altered gene expression in offspring and in…

October 4, 2022

Spectacular Planetary-Scale “Heat Wave” Discovered in Jupiter’s Atmosphere

An unexpected ‘heat wave’ has been discovered in Jupiter’s atmosphere. It reaches a scorching temperature…

October 4, 2022

“Really Impressive” – Astronomers Capture the First Wide-Field Snapshots of X-Ray Universe

EP-WXT Pathfinder has released its first results. EP-WXT Pathfinder, an experimental prototype of a module…

October 4, 2022

“Electric Pill” Shown To Help Patients With Severe COVID-19

Activating the auricular vagus nerve provides anti-inflammatory effects in severe Covid-19 cases. A system out…

October 4, 2022