Supervolcanos have been a topic of many news articles lately. Between the possible eruptions at Yellowstone to the mysteries tied to the earthquakes in Iceland, it seems they are everywhere. They have been documented in Italy and North Korea. A recent discovery in Antarctica only confirms this. A massive supervolcano appears to be bubbling under the ice and may, in fact, challenge some of the current events explained by global warming.
As crazy as it sounds, the folks at NASA played a role in unearthing the Antarctica volcano. Scientists working at the NASA Jet Propulsion Laboratory (JPL) have found evidence that supports an alternative theory to explain the melting that has been seen at the polar ice caps. Instead of it being tied to the human-made changes in the environment called “global warming,” it seems there may be a more natural cause. They have found evidence of a geothermal heat source that is under the thick ice. The unlikely pairing of geothermal heat and ice left some at NASA describing the situation as “…this is crazy.”
The heat comes from what scientists call a mantle plume. According to a report about the recent discovery from NASA:
“A mantle plume is an upwelling of abnormally hot rock within the Earth’s mantle, first proposed by J. Tuzo Wilson in 1963. As the heads of mantle plumes can partly melt when they reach shallow depths, they are often invoked as the cause of volcanic hotspots, such as Hawaii or Iceland, and flood basalts such as the Deccan and Siberian traps. Some such volcanic regions lie far from tectonic plate boundaries, while others represent unusually large-volume volcanism near plate boundaries or in large igneous provinces.”
The hot rocks that make up the mantle plume often come in liquid form and are called magma. NASA described this as being “subterranean molten rock.” This means that the magma is hidden far underground. While it is not visible, it still produces heat that pushes towards the surface of the earth.
This heat has started to melt a great deal of the ice around Antarctica. It may be hard to understand how there can be that much heat under the ice yet not all of the ice melts. This same disbelief was felt by some of the team at NASA who attempted to dismiss the idea altogether.
It seems that the idea of the mantle plume may in fact not being entirely new. There were questions about the theory dating back 30 years, but there was no real way to explore this idea. This is where NASA helped the situation along.
Hélène Seroussi and Erik Ivins from NASA used the Ice Sheet System Model (ISSM) to test the idea out. The ISSM was created via a partnership between the JPL and the University of California, Irvine. The ISSM is “…a mathematical depiction of the physics of ice sheets.”
The original ISSM was altered slightly by Seroussi for the mantle plume project. This means reworking it so that it could also “…hunt for natural heat sources as well as meltwater deposits.”
Using the newest version of the ISSM, they may be able to study the current melt rates and even predict future ice loss. The warming under the surface also explains why some glaciers are forced off larger ice masses. According to a report about the subterranean warming:
“This warm water lubricates the ice sheet from below, allowing glaciers to slide off into the sea. Studying meltwater in western Antarctica may allow scientists to estimate how much ice will be lost in future.”
The part of Antarctica that is the focus of the current NASA work in most commonly referred to as the Marie Byrd Land. The spot between the Ross Sea and the Ross Ice Shelf dates back 50 to 100 million years. This is said to be older than the more significant ice sheets including the Western Antarctic ice sheet.
Because the Marie Byrd Land is older than the ice sheet, it is possible that the mantle is also much older than most things in the area. Like many of the other supervolcanos worldwide, the system under the ice caps could merely be coming out of an extended period of being dormant. The melting ice may not be tied to global warming at all but only a sign that another major eruption is coming.