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Subscribe to RSSWASHINGTON -- Some of Greenland's glaciers are moving about 30 percent faster than they did 10 years ago, contributing to rising global sea levels, but that still may not be enough to reach the most extreme projections for 2100, scientists reported on Thursday.
Researchers have been monitoring the big ice sheets of Greenland and Antarctica for decades as one indication of the impact of human-spurred climate change.
Made of compacted snow, these glaciers can move toward the sea, and when they get there, they dump water into the oceans around them. The faster they move, the more water they add, and the higher the oceans get.
Not all glaciers move at the same pace, according to Twila Moon and her co-authors at the University of Washington and Ohio State University, whose research is published in the current issue of the journal Science.
Inland glaciers with no outlet to the sea poke along at top speeds of 30 to 325 feet a year, the researchers found, while those that end at the ocean can travel 7 miles a year.
The glaciers that flow to the sea around Greenland are the ones to watch, Moon said in a telephone interview, because that is where four-fifths of the loss of ice in Greenland occurs.
Satellite surveys of more than 200 glaciers showed that these comparatively fast-movers in the east, southeast and northwest areas of Greenland increased their speed by an average of 30 percent from 2000 to 2011.
The researchers found that the glaciers heading for the water were not accelerating as much as had been speculated in earlier projections of the worst that could happen. Based on those projections, there was a previous forecast of sea level rise of about 6 feet by century's end.
That would be enough to inundate parts of the U.S. Gulf coast, Alaska, Italy, France, England, Scotland, Denmark, Brazil, India, Sri Lanka, Bangladesh, China, Japan, the Korean peninsula, Southeast Asia and Australia, according to maps of sea level rise at the Center for Remote Sensing of Ice Sheets.
The latest research indicates this is unlikely by 2100.
"Two meters is really kind of a worst case," Moon said. "Now we have the luxury of a little bit more time and being able to actually look at the observations from the last 10 years. At this point it doesn't look like there's any evidence for the worst-case scenario."
A low projection of 8 inches is within reach, the researchers found, and even a small rise in sea level can add to the risks of storm surges and floods. As Moon put it, "If you raise the floor of a basketball court, you're going to have a lot more slam-dunks."
Because multiple factors contribute to sea level rise, it is difficult to determine the exact impact of Greenland's melting glaciers. Global seas have been rising by a bit more than 1 inch a year.
Just knowing how much ice is going into the ocean around Greenland does not give the complete picture, according to a related article in Science. Projections of regional sea level rise are complicated, but they are needed, said co-author Joshua Willis of NASA's Jet Propulsion Laboratory.
"What people really need to know is, how is sea level going to change in my backyard?" Willis said in a telephone interview. To figure that out, he said, scientists must not only figure out the glacier melt situation on a global scale but also add factors like wind, geology, water temperature and even gravity that can have powerful impacts in specific areas.
In southern Louisiana, for example, the land is sinking as the seas are rising, creating a potential double-whammy there. In Greenland, by contrast, the land may actually rise as the weight of heavy ice slides off, like a couch cushion rebounding after a person gets up after a long sit.
Copyright 2013 Thomson Reuters. Click for restrictions.
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I helped build a concrete sea wall in coastal NC, in 1978. The few times it was topped were during extreme high-tides or storms...
The wall is still there and the few times it is topped, is during extreme high tides and storms...
Where is this 1"of sea level INCREASE every year??? According to this article the sea wall should be under 3' of water...
I also own property on the ICW - 1,500' of shore line sense 1995. Again no indications of sea level INCREASING...
I currently live in BKK, which is built on a river delta on the Gulf of Thailand. The average elevation is 1.5 meters above high tide. The city of 13+Million has been here for 300+years. While there has been increased flooding, due to extensive building in known flood areas. It is not due to any rising ocean levels...
Data references for Greenland ice levels:
A. The latest - Rutgers University keeps track of snow cover around the world. Their data show a slight, but steadily increasing snow cover in Greenland since 1966. See graphs for the northern hemisphere as a whole here.
B. Three years ago a decade long study in Greenland indicated a TOTAL 0.05% DECREASE in ice volume. Here is the direct quote from the 13Nov2009 Science Daily article on Greenland ice loss. "Since 2000, the ice sheet has lost about 1500 Gt in total, representing on average a global sea level rise of about half a millimetre per year, or 5 mm since 2000."... Or about 0.020" a year or 0.2" since 2000...
C. Greenland had a multi-year survey conducted that concluded that its ice volume was 703,424 cubic miles or 2,931,000 cubic kilometers during 1999. This was verified by previous surveys that indicated Greenland's ice volume mave have INCREASED by 10% over a 50+year period... see http://nsidc.org/data/docs/daac/nsidc0092_greenland_ice_thickness/parca_paper1.pdf
D. The GRACE data that uses gravity measurements to detect changes in ice mass. After almost a decade of observations & data, the indications are aprox76+cubic miles of ice lose per year... Out of 703,424+cubic miles, which cause me to question the accuracy of the measurments. Espically when they use a data base with a known +-20% error..
In other words this article is more alarmist BS...
If you're not worried about global warming, why on Earth do you post so much about it?
Because the US Media & Politicians are pushing an agenda, contrary to scientific FACT...
The Climate CHANGES, AGW is BS. In fact, almost ALL the accurate data for almost two DECADES is pointing at COOLING trends. Contrary to the IPCC predictions...
Show your current long term scientific data/research that indicates AGW has been correct...
Besides it is a hobby which keeps me up-dated on the current science, NOT headlines...
AC, you seem to completely misunderstand the margin of error for the GRACE experiments.
The reported figure is about 201 +/- 19 Gt/year. That's a 10% margin of error ON THE ACTUAL LOSS.
You seem to think the error (which you misquote as 20%) is on the entire mass of ice over Greenland, which is absurd -- if you are going to do that, why not make it the margin of error for the tectonic plate that Greenland sits on, or the entire Earth for that matter?
JimCA,
The reported figure was 100+cubic miles for Greenland & Antarctica COMBINED...
Later they specified that Antarctica was losing 24-cubic miles a year. Out of a TOTAL of 6+Million cubic miles...
This left Greenland with losing 76+cubic miles a year. Out of a TOTAL of 703,424 cubic miles...
The Data base they are using to make these estimates is based on the estimates of continental rebound. Which has, on the GRACE web site, stated that this data base has a +-20% ERROR...
No matter how accurate you state your measurements are. When you base data has +-20% ERRORs, your conclusions will reflect this ERROR...
BTY - The center of Greenland is still being depressed further, due to the INCREASING volumes of ICE...
Moved...
Doug, AC seems to have a bug up his ass and goes to great lengths to dredge up any scrap of data that supports his preconceived notions, while totally ignoring or attempting to dismiss as faulty the 99.99% of the data that challenges his assumptions.
Either that or he's paid by the post, as many are, but I'm inclined to think that's not his problem.
And I have no idea why this won't appear as a reply.
I give the references to support by conclusions. If you notice the research was from NASA, NOAA, NSIDC, Rutgers, etc, etc. Not one deniers web site...
Where are YOUR references that support a 1" sea level rise a year???
Or the long term studies of the ice volume in Greenland, that support DECREASING trends???
Then you can tell use about Mann's Hockey stick and how well the actual temperatures are tracking that...
Or the Himalayas glacier melting...
Or the Global temperature rise in relation to atmospheric CO2 levels...
It is now a proven FACT that the IPCC& the Alarmist predictions have almost entirely FAILED to materialize...
What about the AGW Alarmist that admitted that he was WRONG. This was reported in MSNBC, just last week. for video see - http://www.bing.com/videos/search?q=Climate+arlimist+admits+he+was+wrong&qpvt=Climate+arlimist+admits+he+was+wrong&FORM=VDRE
Talk is cheap - Viable references are what proves your point... So far you have supplied ZERO...
James Lovelock, the maverick scientist who became a guru to the environmental movement with his “Gaia” theory of the Earth as a single organism, has admitted to being “alarmist” about climate change and says other environmental commentators, such as Al Gore, were too.
'I made a mistake'
As “an independent and a loner,” he said he did not mind saying “All right, I made a mistake.” He claimed a university or government scientist might fear an admission of a mistake would lead to the loss of funding.
Lovelock -- who has previously worked with NASA and discovered the presence of harmful chemicals (CFCs) in the atmosphere but not their effect on the ozone layer -- stressed that humanity should still “do our best to cut back on fossil fuel burning” and try to adapt to the coming changes.
Here is the MSNBC reference - http://worldnews.msnbc.msn.com/_news/2012/04/23/11144098-gaia-scientist-james-lovelock-i-was-alarmist-about-climate-change#.T5WJZfZrYcs.twitter
Yada, yada, yada. If this endless debate over global warming amongst us non-climatologists would ever accomplish something it would be one thing, but the endless banter back and forth does nothing more than add meaningless fuel to the fire. Either we lay types agree with the 97% of earth's scientists or not!
The author of this article is not familiar with the material she is writing about. The IPCC's worst case scenario foresees the ocean rising .5 meters by 2100. Deborah states a rise of an inch a year which means the ocean will rise over 7 feet by the end of the century. That is way above the IPCCs worst case scenario.
As the story says, the calculations as to the actual warming, ice melt, and effects are complicated. They are also complicated by the lasting effects of the last ice age. In Ohio (my state) the land is still rebounding (rising) as a result of the retreat of the last glacier. This is a quote from The effect of glaciation on Ohio: "Once the ice retreated, the land slowly started rebounding. It is still rebounding today and is responsible for the formation of many of the cliffs along the southern shore of Lake Erie." Since the land in Ohio and other previously glaciated areas is rising, it follows that other parts of the globe must be sinking. At present, the global sea ice area is actually slightly higher than the 1979-2008 mean. (Link) There is even uncertainty over the peak temperatures during the last several interglacial periods.
There is no doubt that the earth has warmed dramatically in the last 10,000 years. To what degree humans have influenced or caused the apparent recent surge in warming is still debatable. Until I can grow figs outside unprotected in Ohio, it has not warmed enough for me.
Jump ahead to May 2012 and a new record for ice in the Bering Sea.
http://wattsupwiththat.com/2012/05/03/another-sea-ice-record-in-the-bering-sea-plus-april-sea-ice-summary/
I love how MSNBC changes the entire tune of the study.
http://notrickszone.com/2012/05/04/new-paper-large-greenland-glaciers-ending-on-land-or-in-fjords-have-hardly-changed-or-have-even-become-slower/
Meanwhile the Bering Sea just set a new record for ice.
http://wattsupwiththat.com/2012/05/03/another-sea-ice-record-in-the-bering-sea-plus-april-sea-ice-summary/