Study: West Antarctic Glacier Melt Due To Volcanoes, Not Global Warming

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A new study by researchers at the University of Texas, Austin found that the West Antarctic Ice Sheet is collapsing due to geothermal heat, not man-made global warming.

Researchers from the UTA’s Institute for Geophysics found that the Thwaites Glacier in western Antarctica is being eroded by the ocean as well as geothermal heat from magma and subaerial volcanoes. Thwaites is considered a key glacier for understanding future sea level rise.

UTA researchers used radar techniques to map water flows under ice sheets and estimate the rate of ice melt in the glacier. As it turns out, geothermal heat from magma and volcanoes under the glacier is much hotter and covers a much wider area than was previously thought.

“Geothermal flux is one of the most dynamically critical ice sheet boundary conditions but is extremely difficult to constrain at the scale required to understand and predict the behavior of rapidly changing glaciers,” UTA researchers wrote in their study, which was published in the Proceedings of the National Academy of Sciences.

The geothermal heat under the glaciers is likely a key factor in why the ice sheet is currently collapsing. Before this study, it was assumed that heat flow under the glacier was evenly distributed throughout, but UTA’s study shows this is not the case. Heat levels under the glacier are uneven, with some areas being much hotter than others.

“The combination of variable subglacial geothermal heat flow and the interacting subglacial water system could threaten the stability of Thwaites Glacier in ways that we never before imagined,” lead researcher David Schroeder said in a press release.

“It’s the most complex thermal environment you might imagine,” echoed co-author Don Blankenship “And then you plop the most critical dynamically unstable ice sheet on planet Earth in the middle of this thing, and then you try to model it. It’s virtually impossible.”

Scientists and environmentalists have been pointing to Antarctica’s collapsing western ice sheet as further evidence the planet is warming. NASA glaciologist Eric Rignot recently found that the western ice sheet collapse is “unstoppable” and could dramatically raise sea levels.

“The highest storm surge from Hurricane Sandy, or Superstorm Sandy, was just under 13 feet, and a whole lot of places it was 10 feet or less,” Penn State University glaciologist Richard Alley told Mother Jones’ Chris Mooney in a podcast.

“And we’re looking at 11 feet, or something like that, from West Antarctica,” Alley said. “Plus a little thermal expansion [water expanding as it gets warmer] and some mountain glacier melting that are already on the table. And so you can sort of think of the storm surge of Hurricane Sandy, something vaguely in that neighborhood for most of the coastline of the world.”

But reports of the western ice sheet’s collapse comes as Antarctic ice sheets continue to break records. At the end of May, Antarctic sea ice extent reached the highest level since measurements began in 1979.

Sea ice extent reached nearly 13 million square kilometers — 10.3 percent above the 1981-2010 climatological average of 11.7 million square kilometers. The previous record was 12.7 million square kilometers set in 2010

Antarctic Glacier Melt Due To Volcanoes, Not Global Warming | The Daily Caller

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All that man-made climate change rhetoric, and little proof to back it up

The cold waters of Earth’s deep ocean have not warmed measurably since 2005, according to a new NASA study, leaving unsolved the mystery of why global warming appears to have slowed in recent years.

Scientists at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California, analyzed satellite and direct ocean temperature data from 2005 to 2013 and found the ocean abyss below 1.24 miles (1,995 meters) has not warmed measurably. Study coauthor Josh Willis of JPL said these findings do not throw suspicion on climate change itself.

"The sea level is still rising," Willis noted. "We're just trying to understand the nitty-gritty details."

In the 21st century, greenhouse gases have continued to accumulate in the atmosphere, just as they did in the 20th century, but global average surface air temperatures have stopped rising in tandem with the gases. The temperature of the top half of the world's oceans -- above the 1.24-mile mark -- is still climbing, but not fast enough to account for the stalled air temperatures.

Many processes on land, air and sea have been invoked to explain what is happening to the "missing" heat. One of the most prominent ideas is that the bottom half of the ocean is taking up the slack, but supporting evidence is slim. This latest study is the first to test the idea using satellite observations, as well as direct temperature measurements of the upper ocean. Scientists have been taking the temperature of the top half of the ocean directly since 2005, using a network of 3,000 floating temperature probes called the Argo array.

"The deep parts of the ocean are harder to measure," said JPL's William Llovel, lead author of the study published Sunday in the journal Nature Climate Change. "The combination of satellite and direct temperature data gives us a glimpse of how much sea level rise is due to deep warming. The answer is -- not much."

The study took advantage of the fact that water expands as it gets warmer. The sea level is rising because of this expansion and the water added by glacier and ice sheet melt.

To arrive at their conclusion, the JPL scientists did a straightforward subtraction calculation, using data for 2005-2013 from the Argo buoys, NASA's Jason-1 and Jason-2 satellites, and the agency’s Gravity Recovery and Climate Experiment (GRACE) satellites. From the total amount of sea level rise, they subtracted the amount of rise from the expansion in the upper ocean, and the amount of rise that came from added meltwater. The remainder represented the amount of sea level rise caused by warming in the deep ocean.

The remainder was essentially zero. Deep ocean warming contributed virtually nothing to sea level rise during this period.

Coauthor Felix Landerer of JPL noted that during the same period warming in the top half of the ocean continued unabated, an unequivocal sign that our planet is heating up. Some recent studies reporting deep-ocean warming were, in fact, referring to the warming in the upper half of the ocean but below the topmost layer, which ends about 0.4 mile (700 meters) down.

Landerer also is a coauthor of another paper in the same journal issue on 1970-2005 ocean warming in the Southern Hemisphere. Before Argo floats were deployed, temperature measurements in the Southern Ocean were spotty, at best. Using satellite measurements and climate simulations of sea level changes around the world, the new study found the global ocean absorbed far more heat in those 35 years than previously thought -- a whopping 24 to 58 percent more than early estimates.

Both papers result from the work of the newly formed NASA Sea Level Change Team, an interdisciplinary group tasked with using NASA satellite data to improve the accuracy and scale of current and future estimates of sea level change. The Southern Hemisphere paper was led by three scientists at Lawrence Livermore National Laboratory in Livermore, California.

NASA monitors Earth's vital signs from land, air and space with a fleet of satellites and ambitious airborne and ground-based observation campaigns. NASA develops new ways to observe and study Earth's interconnected natural systems with long-term data records and computer analysis tools to better see how our planet is changing. The agency shares this unique knowledge with the global community and works with institutions in the United States and around the world that contribute to understanding and protecting our home planet.

NASA Study Finds Earth?s Ocean Abyss Has Not Warmed | NASA