Hot magma is melting Greenland ice – can windfarms save it?

Here on the ball of magma called Earth, there’s a hot plume of rocks under Iceland that stretches right across under Greenland. Those hot rocks are melting the ice from below in a band 1,200 km long and 400 km wide.[1]

I don’t think solar panels are going to stop Greenland melting.

The main part of the plume has been progressing eastward over the last 120 million years, right under Greenland and now lies under Iceland.

Will the media take a million years to catch on?

Presumably, being world class journalists, from now on all ABC/BBC/CBC stories will not mention melting Greenland ice-sheets without also noting that geothermal heat may be causing it instead of your long hot showers.

But a similar study published in Nature Geoscience 3 years ago was the forerunner to this one with similar conclusions and the mainstream media don’t seem to have noticed yet.[2] No mention of magma, tectonics and hot rocks here: ABC — Antarctica’s melting ice alone could lift sea levels one metre by 2100, March 31st, 2016. Or here: ABC — Global warming melts last stable edge of Greenland’s Zachariae ice stream, March 17th, 2014. Or on the BBC – Ice sheet losses double, 2014. Or here — ABC: Antarctic ice shelf collapse “very likely”. October 2015.

There’s a hot blob under West Antarctica too

Likewise, soon the public broadcasters will let listeners know that West Antarctica lies over the southern edge of the Pacific Rim, and “might” have some geothermal heat from below too because there is giant blob of superheated rock there too. [3]

Abstract

Ice-penetrating radar and ice core drilling have shown that large parts of the north-central Greenland ice sheet are melting from below. It has been argued that basal ice melt is due to the anomalously high geothermal flux that has also influenced the development of the longest ice stream in Greenland. Here we estimate the geothermal flux beneath the Greenland ice sheet and identify a 1,200-km-long and 400-km-wide geothermal anomaly beneath the thick ice cover. We suggest that this anomaly explains the observed melting of the ice sheet’s base, which drives the vigorous subglacial hydrology3 and controls the position of the head of the enigmatic 750-km-long northeastern Greenland ice stream. Our combined analysis of independent seismic, gravity and tectonic data implies that the geothermal anomaly, which crosses Greenland from west to east, was formed by Greenland’s passage over the Iceland mantle plume between roughly 80 and 35 million years ago. We conclude that the complexity of the present-day subglacial hydrology and dynamic features of the north-central Greenland ice sheet originated in tectonic events that pre-date the onset of glaciation in Greenland by many tens of millions of years.

REFERENCES

[1^] A. G. Petrunin, I. Rogozhina, A. P. M. Vaughan, I. T. Kukkonen, M. K. Kaban, I. Koulakov & M. Thomas (2013) Heat flux variations beneath central Greenland’s ice due to anomalously thin lithosphere. Nature Geoscience 6, 746–750 (2013) doi:10.1038/ngeo1898

[2^] Irina Rogozhina, Alexey G. Petrunin, Alan P. M. Vaughan, Bernhard Steinberger, Jesse V. Johnson, Mikhail K. Kaban, Reinhard Calov, Florian Rickers, Maik Thomas & Ivan Koulakov Melting at the base of the Greenland ice sheet explained by Iceland hotspot history(2016) Nature Geoscience, Letter, doi:10.1038/ngeo2689

[3^] Lloyd et al (2015) A seismic transect across West Antarctica: Evidence for mantle thermal anomalies beneath the Bentley Subglacial Trench and the Marie Byrd Land Dome. Journal of Geophysical Research: Solid Earth, 2015; DOI: 10.1002/2015JB012455

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