‘Shockwaves from melting icecaps are triggering earthquakes, say scientists’
This relates the chilling news that the melting of Greenland's ice sheet has accelerated so dramatically that it is triggering earthquakes for the first time which register up to 3 on the Richter scale.
Key points to note are:
1 These glacial ice quakes were unknown in that region 3 years ago.
2 The paper considers them to be ‘among the latest ominous signs that an unprecedented step change is under way’.
3 That the acceleration in melting is so great it is outstripping the ability of scientists to predict it, while proving current predictions hopelessly optimistic in a matter of months – we are already at 2040 on a model produced 5 years ago, and will be at 2050 next year; an IPCC report issued this February is already considered out of date.
4 Glaciers are also starting to move rapidly – at up to 2 metres an hour – as a result of the lubrication caused by melt water, causing them to discharge into the sea at an accelerating rate.
5 Similar effects are being felt in Alaska where tectonic activity is being triggered by the relief of pressure due to the reduced amount of ice resting on the plates.
6 The predicted sea level rises in IPCC 4 (the latest) of 50 to 60 cm are now extremely dubious, and the consensus according to the article is now around two metres. The difference is critical.
7 In the north of Sweden, mean temperatures have risen above zero for the first time on record – ie it is in net meltdown for the first time since the last ice age or longer.
All that has been said in previous posts has dealt solely with the meltdown of the North Polar region. In other words it was made on the basis of an unrealistic and very optimistic assumption because it ignored the melting of the Greenland Icecap and Antarctica.
The reason for that assumption was that there seems now to be irrefutable evidence for the former; whilst the latter are clearly melting, the implications are more conjectural.
In the case of Greenland and the Antarctic, there have been extremely worrying signs from both for a considerable time. However because of their very different character, the unprecedented nature of the events unfolding, the lack of clarity as to what is happening to them and their responses as a system, their situation remains open to interpretation and the scientific position has yet to form a firm consensus.
In other words we don’t really know what is going on or what it is going to lead to.
As most will be aware, both regions are true continents lying beneath several kilometres of ice, while the North Polar region is nothing but a layer of ice floating in the sea. In comparison it is extremely thin – the submarines which surface through the ice can only do so where it is less than three and a half metres thick.
A critical issue is sea level rise. The melting of the North Pole makes no difference at all to sea level, because it is already floating in the water. That is not the case for the ice-bound continents. As the article says:
‘Greenland's ice cap is immense, the second largest in the world, and its break-up would be catastrophic. The packed ice is up to two miles thick and its total collapse into the ocean would raise worldwide sea levels by seven metres.’
In addition, we must assume that corresponding effects are happening to Antarctica during the Southern Hemisphere summer.
‘Estimates of the likely rise in sea levels this century vary, and the IPCC published a conservative range of between 20cm-60cm. But those estimates are now heavily disputed, with many scientists insisting that new data collected since the IPCC report suggested a rise closer to two metres.’
This will spell the end for many island states, for instance Vanuatu in the Pacific where the highest point is 4 metres above sea level. The knock-on effects would be dramatic, and the effects on climate of an increased proportion of sea on the earth’s surface unpredictable.
These finding illustrate most clearly the absolute frailty of the predictions we are relying on to determine our response to climate change. In a very short space of time the best science has been shown to have produced predictions that are completely unrealistic and hopelessly optimistic.
The lesson is clear. In such a situation the only sane response is to follow the precautionary principle to the letter.
Tragically we continue to do exactly the opposite.
The article should be read in full if at all possible. But for those lacking the time, a few more highlights are quoted below the URL.
http://environment.independent.co.uk/climate_change/article2941866.ece
‘The speed of the arctic ice melt has accelerated to such an extent that a UN report issued in February is now thought to be out of date by its own authors who describe the acceleration [in melting] as "massive".’
A key member of the IPCC said
"It's moving toward the sea at a rate of two metres an hour. It's exuding like toothpaste, moving towards us at 15 kilometres per year."
‘As the reality of the unprecedented thaw becomes apparent, the consequences are outstripping the capacity of scientific models to predict it.’
‘Predictions made by the Arctic Council, a working group of regional scientists, have been hopelessly overrun by the extent of the thaw. "Five years ago we made models predicting how much ice would melt and when," said Mr Vallio. "Five years later we are already at the levels predicted for 2040, in a year's time we'll be at 2050."’
‘This dramatic warming is being felt across the Arctic region. In Alaska, earthquakes are rocking the seabed as tectonic plates – subdued for centuries by the weight of the glaciers on top of them – are now moving against each other again.’
‘In the north of Sweden, mean temperatures have risen above zero for the first time on record.’
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