Skip to Content
Uncategorized

A Clearer Picture of Global Warming

Continuous GPS stations in Greenland could improve our understanding of melting ice sheets.
August 9, 2007

One of the wildcards of global warming is how fast the world’s massive ice sheets are melting. Efforts to measure the rate of melting on Greenland and Antarctica–and thereby predict how fast sea levels will rise–are complicated by something called “post-glacial rebound” of the earth’s crust. When the crust is relieved of its millennia-long burden of ice, it shifts around a bit, and springs back.

Earth signs: A one-meter tall station (above) was installed last Thursday near Ilulissat to measure how much the earth’s crust rebounds as the ice sheet melts. Such measurements could help scientists better predict how fast sea levels will rise.

In the first comprehensive effort to correct for this phenomenon, scientists from an international team are scurrying around Greenland this summer to install 24 continuous GPS stations into bedrock around the coast. They’re also rigging them up with solar panels and large battery packs to keep them powered up through bitterly cold winters.

A one-meter-tall station was installed last Thursday near Ilulissat, on the west coast of Greenland, by members of the team from Denmark, Luxembourg, and the United States. Today, a team that includes Mike Willis, a PhD candidate at Ohio State, and Thomas Nylen, an engineer from the contractor UNAVCO of Boulder, CO, is flying out to the east coast to install one near Kulusuk.

The stations can detect lateral and vertical changes of the Earth’s crust down to the millimeter scale. Equally important, they’ll continuously beam out their readings. This data should allow other sensors–which monitor elevation changes, glacial outflow rates, and overall mass of the great ice sheets–to become far more accurate in measuring the rate of ice loss. The international team plans on installing 16 stations in Antarctica later this year as part of the project.

The units should be of particular help in complementing a NASA satellite system called GRACE–Gravity Recovery and Climate Experiment. GRACE takes readings on ice-sheet mass, as inferred by changes in gravitational pull, every 30 days. While GRACE has transformed scientists’ understanding of ice sheet changes, it cannot tell with precision which areas of an ice sheet are losing mass. Nor can it directly correct for post-glacial rebound.

Greenland’s and Antarctica’s ice sheets contain enough ice to raise sea levels 70 meters, if it all melted. And in recent years, evidence has been mounting for accelerating ice loss. The additional information provided by the continuous GPS stations could help researchers improve the accuracy of their measurements.

David Talbot is reporting from Kangerlussuaq, Greenland.

Keep Reading

Most Popular

Workers disinfect the street outside Shijiazhuang Railway Station
Workers disinfect the street outside Shijiazhuang Railway Station

Why China is still obsessed with disinfecting everything

Most public health bodies dealing with covid have long since moved on from the idea of surface transmission. China’s didn’t—and that helps it control the narrative about the disease’s origins and danger.

individual aging affects covid outcomes concept
individual aging affects covid outcomes concept

Anti-aging drugs are being tested as a way to treat covid

Drugs that rejuvenate our immune systems and make us biologically younger could help protect us from the disease’s worst effects.

Europe's AI Act concept
Europe's AI Act concept

A quick guide to the most important AI law you’ve never heard of

The European Union is planning new legislation aimed at curbing the worst harms associated with artificial intelligence.

Stay connected

Illustration by Rose WongIllustration by Rose Wong

Get the latest updates from
MIT Technology Review

Discover special offers, top stories, upcoming events, and more.

Thank you for submitting your email!

Explore more newsletters

It looks like something went wrong.

We’re having trouble saving your preferences. Try refreshing this page and updating them one more time. If you continue to get this message, reach out to us at customer-service@technologyreview.com with a list of newsletters you’d like to receive.