One of Antarctica’s major glaciers, Nansen, is rapidly melting supposedly due to man-made global warming, at least according to a just-released article by Tech Times, but geologic forces are the likely culprit.
Scientific support for the article was taken from a research study by the European Space Agency (ESA), an organization that has for many years been monitoring changes in the Nansen Glacier utilizing satellite images.
Figure 1. Summit of Antarctica’s 12,488 foot Mount Erebus.
These satellite images clearly document the fracturing and eventual breakup of a large terminal segment of the Nansen Glacier.
Tech Times contends that the ESA study and associated satellite images are “smoking gun” evidence that man-made global warming is destroying our planet, specifically in this case melting Antarctic glaciers.
Taken at face value this appears very plausible because the article is based on research by a trusted space agency that almost certainly followed sound research procedures and protocols while interpreting reliable satellite data.
Well, hold on, because it turns out that Tech Times and the ESA did not tell the whole story!
By incorporating the geology of Antarctica into this research study and resulting article it becomes apparent that sub-glacial geothermal heat flow from volcanoes, hot springs, and major faults is the likely cause of geographically limited melting of the Nansen Glacier. The details of this geological story are as follows.
Let’s begin by redirecting our attention away from the supposed smoking-gun satellite photos and onto the definite smoking-gun geological heat flow photo above (Figure 1).
This is a present-day photo of Antarctica’s Mount Erebus, which lies along a string of volcanoes and hot springs that are associated with a 3,300 mile long actively heat emitting fault zone that crosses directly underneath the Nansen Glacier.
This giant fault zone, the West Antarctic Rift (see here), is literally ripping the Antarctic Continent apart (Figure 2).
Figure 2. Bedrock (ice removed) view of the Antarctic Continent showing high mountains (red), deep valleys (blue), and the bedrock trace of the branching West Antarctic Rift/Fault Zone. (for scale; Antarctica covers more area than the lower 48 US States)
The process of fault movement along the West Antarctic Rift creates fractures that extend vertically downward deep into the earth, tapping large chambers of hot magma (hot lava). Extensive research has proven that this fault movement driven process generates a very efficient and extensive circulation system that acts to capture, super-heat, chemically charge and then expulse now altered water vertically upward along the fault zone onto the shallower bedrock surface.
In some cases, this bedrock expulsion point is at the crest of active volcanoes like Mount Erebus. In many other cases, the bedrock expulsion point is at the base of ice sheets or glaciers. Here the expulsed heat acts to basal melt, thin and then weaken the overlying ice sheet. This is exactly what happened to the terminal end of the Nansen Glacier, which once weakened fractured and broke loose out into the adjacent Ross Sea.
Information cited above represents a very small sample of the vast amount of research which proves that geologically induced heat flow plays a major role in effecting Antarctica’s ice sheets and ocean. Other significant ways geological forces have affected Antarctica are as summarized follows:
Geologically induced super-heated fluid flow from the West Antarctic Rift/fault has melted the base of the overlying 5,000-6,000 foot thick ice sheet thereby creating a huge interconnected sub-ice sheet fresh water system.
This system extends for thousands of miles beneath Antarctica’s ice sheet, primarily in locations directly above the fault zone. This huge sub-ice sheet freshwater system has been verified by drilling down into basal freshwater lakes, streams, and numerous hot springs.
Overall Antarctica has gained ice mass for 35 consecutive years. Ice mass above the fault has diminished, but not enough to alter the overall gain for the entire continent.
New research has confirmed that where the West Antarctic Rift continues into the surrounding oceans there are currently active deep ocean volcanoes associated with the fault.
Other new research has confirmed that ocean floor volcanic activity has significantly warmed the shallow ocean waters surrounding a volcanic platform off the coast of Antarctica (1,250-mile-long Kerguelen Plateau).
Antarctic Ice core data proves that sub-ice sheet volcanic eruptions located along the West Antarctic Rift faults have occurred several times in the recent past, 23,000 and 45,000 years ago. These eruptions acted to melt significant portions of the ice sheet above the fault.
Mount Erebus is currently in a mild eruptive phase and is very close to the Nansen Glacier (Figure 3).
Figure 3. Google earth image Mount Erebus volcano, Mount Terror volcano, Mount Bird volcano, West Antarctic Rift, and Nansen Glacier as it enters the Ross Sea (for scale: 150 miles from Mount Erebus to Nansen Glacier
In summary overwhelming amounts of reliable data and research prove that geological forces, primarily in the form of heat flow from active volcanoes and faults, have in past and continue to dramatically affect Antarctica’s ice sheets and oceans. Discussions concerning the melting of Antarctic glaciers, such as the Nansen, should give this notion consideration.
James Edward Kamis is a Geologist and AAPG member of 42 years with a B.S. and M.S. in geology who has always been fascinated by the connection between Geology and Climate. More than 10 years of research/observation have convinced him that the Earth’s Heat Flow Engine, which drives the outer crustal plates, is also an important driver of the Earth’s climate. The Plate Climatology Theory was recently presented at the annual 2016 American Meteorological Society Conference in New Orleans, LA.
REFERENCES
http://usatoday30.usatoday.com/weather/antarc/avolcano.htm
http://volcano.si.edu/volcanoes/region19/antarct/erebus/3609ere2.jpg
http://jonova.s3.amazonaws.com/photos/antarctica/antarctic-volcano-350.gif
http://www.livescience.com/49167-antarctica-volcanoes-erupted-through-ice.html
