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Canadian Ice Shelves Halve In Six Years
eldavojohn writes "The CBC reports on new research that shows thousand-year-old ice shelves (much different than sea ice) are breaking up and have been reduced by half in a region of Canada over the last six years. 'This summer alone saw the Serson ice shelf almost completely disappear and the Ward Hunt shelf split in half. The ice loss equals about three billion tonnes, or about 500 times the mass of the Great Pyramid of Giza.' More detailed pictures can be seen at The Conversation, with a quote from Professor Steven Sherwood, Co-Director of the University of NSW's Climate Change Research Centre: 'The real significance of this, in my view, is that this ice has reportedly been there for thousands of years. The same is true of glaciers that have recently disappeared in the Andes. These observations should dispel in one fell swoop any notion that recent global warming could be natural.'"
It has never and will never be that easy, Steve. Your optimism is appreciated though.
These observations should dispel in one fell swoop any notion that recent global warming could be natural.
So you are saying that if there was natural global warming these ice shelves wouldn't melt? That's pretty amazing!
love is just extroverted narcissism
Those didn't disappear in six years.
Summaries like this irk me. It ends with "These observations should dispel in one fell swoop any notion that recent global warming could be natural." This is a complete invalid conclusion.
"These observations should dispel in one fell swoop any notion that recent global warming is not happening." is a more reasonable statement based on the facts presented.
As to proving that it is not natural, that is a different argument that needs to be made by demonstrating the causes not reciting the symptoms.
-- This sig is only a test. If this were a real sig it would say something witty. --
No, but we have documented proof that both Europe and North America were experiencing a "mini ice age" as late at the mid-1800's, and that before the early 1700's (when the mini ice-age started) it was warmer than it is now.
There are 2 basic threads to anti-anthropogenic global warming arguments...
The first is, "It's not really happening, you've cherry-picked your data and/or misinterpreted it." and the refutation usually seems to consist of cherry-picked data with very specific interpretations.
The second is, "It's not anthropogenic, it's natural, because of..." with some reason or other.
For the moment I won't take sides on either thread, but I'm going to take very serious issue with the second. However I get the very distinct feeling with both threads that the real message is, "Since global warming is not real / not anthropogenic, we don't need to modify our actions. We can keep our fossil-fuel-based energy and transportation, unmodified." (and business models, might I add...)
But assuming you're on the second thread, and assuming you're saying that global warming is real, just not man-caused, it must be apparent that we simply cannot keep going the way we are. We must come to grips with a changing environment. Global warming means more energy into the atmosphere, and that means more water evaporates and moves from place to place. Some places get even more water, some places get even less, storms get stronger, and it's not even a smoking-gun kind of thing, it's statistical. No new killer drought or killer flood or killer tornado, just a slow ramp on the severity and frequency of the ones we have.
All the while people living in marginal areas get stressed, our agricultural systems get stressed, our emergency response systems get stressed. It's not "a disaster", it's more of the disasters we've had all along.
Not planning for it, not studying it very carefully to understand the extent, not taking some action to mitigate it, is hiding our head in the sand, and waiting to get smacked in the butt.
When you get flattened by a giant rock, you're just as dead if the rock rolled off a cliff as if it was dropped by a crane. One is "natural", the other "anthropogenic", but you're still dead.
The living have better things to do than to continue hating the dead.
Some glaciers should grow due to AGW while others should shrink. We can, to a degree, model which ones should grow and which ones should shrink (but that's a bit harder than recognizing the generality).
AGW raises that atmosphere's temperature, and its temperature affects glaciers by at least two general proximal mechanisms: more or less directly, by melting them, melting the snow that would accumulate to form them, lubricating their flow, etc.; and by changing the amount and type of precipitation that might fall on them. The mass of a glacier is dictated by the balance between melting and accumulation. If the extra moisture in the atmosphere falls as significantly more snow than would have fallen without AGW, as might occur at certain latitudes and elevations, or due to peculiarities of geography, it can swamp the loss of mass caused by warming. Those glaciers will accumulate mass even in spite of somewhat higher temperatures.
The most endangered glaciers are those at modest latitudes and elevations, especially in places that don't get dramatic amounts of snowfall, or areas that will see adverse changes in precipitation levels and patterns as a result of climate change.
That said, I have no idea how Mt. Logan might be affected by this dynamic, but no single mountain or glacier's behavior will prove or disprove anything about climate change. Overall, however, the world's long-lived temperate glaciers are losing mass and receding, the cause of which can only be climate related. The most reasonable explanation for the abrupt change is AGW.