Hot Mantle Plume Is Melting Antarctica From Beneath, NASA Study Finds

Share

Although the heat source isn't a new or increasing threat to the West Antarctic ice sheet, it could help explain why the ice sheet collapsed rapidly some 11,000 years ago and why it's so unstable today, Seroussi said.

Mantle plumes are believed to be narrow streams of hot, molten rock which erupts through Earth's mantle and forms a mushroom cap-like structure under the crust.

Illustration of flowing water under the Antarctic ice sheet.

The stability of ice sheets is closely related to the quantity of water beneath the sheets. The team developed a mantle plume model to look at how much geothermal heat would be needed to explain what is seen at Marie Byrd Land.

Warriors survive without Durant, roll past Wolves
Through 11 games this season, Durant is averaging 24.8 points, 7.7 rebounds, 5.0 assists and 2.5 blocks. The ball movement proved too much for Minnesota, as Golden State assisted on 37 of its 48 field goals.

The research could help scientists better estimate future ice loss in the area. Blue dots indicate lakes and lines show rivers.

However, recent seismic imaging seems to confirm the hypothesis.

Study author Hélène Seroussi, from JPL, said when she first heard that a mantle plume might be heating Marie Byrd Land she thought the idea was "crazy". The rapid filling and draining of lakes and rivers in the Antarctica result in rising or falling of ice sheaths to almost 20 feet (6 meters). The Numerical modeling helped to gain an idea of the functioning of the mantle plume concept.

They scientists also used observations of changes in the altitude of the ice sheet surface, captured by NASA's IceSat satellite and airborne Operation IceBridge campaign.

Clemson's Dabo Swinney shows utmost respect for FSU despite 3-5 record
Florida State ranks last in the ACC in turnover margin, last in tackles for loss allowed and 12 in penalty yards per game. College football coaches across the ACC have been cordial and complementary of FSU throughout the team's 3-5 season.

"These place a powerful constraint on allowable melt rates - the very thing we wanted to predict", Ivins said. The researchers used multiple parameters including dozens of different simulations as the location and size of the mantle plume is still unknown.

In the past, researchers had observed volcanic activity and a topographic dome feature in this region. "In contrast, the active lake system of the lower part of Whillans Ice Stream suggests a widespread anomalous mantle heat flux, linked to a rift source", the researchers wrote in the abstract of their study.

The study found that the energy flux from the mantle plume must not exceed 150 milliwatts per square meter - compared, for example, to a heat flux of 490 to 60 milliwatts in regions with no volcanic activity, and an average 200 milliwatts per square meter beneath Yellowstone.

Concluding, the team say the Marie Byrd Land mantle plume formed 50-110 million years ago-long before the land above was hidden by ice.

US, South Korea, Australia Hold East China Sea Navy Drills
There's really only one thing the west wants from Kim and that's for him to abandon his nuclear weapons program. US President Donald Trump delivers a speech at the National Assembly in Seoul on November 8, 2017.

When Antarctica lost an enormous iceberg from the Larsen C ice shelf in July, it set off alarm bells about the future of the shelf itself, as well as about the region in general, which like other ice repositories on Earth, is faring badly under the onslaught of global warming.

Share