Arctic ice faces accelerated meltdown

SpaceDaily ^ | 12/12/2006 | AFP

[monkfan]

Looks like a good, but long, read. Bookmarking for later...

[rahbert]

Not a good thing if permafrost melts. Structures cannot
prevail in marshes.

[jwalsh07]

Evidently not so apparent.

[jwalsh07]

Inhofe states clearly that he thinks anthropogenic global warming is a hoax. He's wrong.

Again you misquote him. Just what the hell is wrong with quoting somebody accurately?

[spokeshave]

1. Global warming is caused by CO2 emissions from Thailand forest burning so they can grow palm oil trees to make bio-diesel fuel to satisfy the environazis.

2. Additional cause is massive emissions of soot from Chinese coal fired power stations that condenses on arctic ice causing increased absorbtion of sun energy and thus melting gthe ice.

3. Not to worry as the melting fresh water will turn off the gulf stream thas starting anoter 400 yera "mini" ice age in N. Europe that should polease trhe global warmers.

[secretagent]

Efforts to measure changes in the Greenland Ice Sheet using field observations, aircraft and satellites have improved scientific knowledge during the last decade, but there is still no consensus assessment of the ice sheet's overall mass balance. There is however evidence of melting and thinning in the coastal marginal areas in recent years, as well as indications that large Greenland outlet glaciers can surge, possibly in response to climate variations.

So according to your linked site, no consensus. Increased interior ice, and decreased perimeter ice.

Using more recent data:

The critical point for Greenland is whether the increased rate of glacier motion more than compensates for the greater accumulation on the surface. While the broad picture of what is happening is consistent between these papers, the bottom-line value for Greenland's mass balance is different in all three cases. Looking just at the dynamical changes observed by Rignot & Kanagaratnam, there is an increased discharge of about 0.28 mm/year SLE from 1996 to 2005, well outside the range of error bars. This is substantially more than the opposing changes in accumulation estimated by Johannessen et al and Zwally et al, and is unlikely to have been included in their assessments. Thus, the probability is that Greenland has been losing ice in the last decade. We should be careful to point out though that this is only for one decade, and doesn't prove anything about the longer term. As many of the studies make clear, there is a significant degree of interannual variability (related to the North Atlantic Oscillation, or the response to the cooling associated with Mt. Pinatubo) such that discerning longer term trends is hard.

http://www.realclimate.org/index.php/archives/2006/03/greenland-ice-and-other-glaciers/

Again, it looks like no consensus of loss or gain.

[UpAllNight]

What is the temperature trend from 1998 to 2006?

[jwalsh07]

I can live with that but the article on the study I linked you to states this:

"The spatially averaged increase is 5.4 cm per year over the study area, when corrected for post-Ice Age uplift of the bedrock beneath the ice sheet. These results are remarkable because they are in contrast to previous scientific findings of balance in Greenland's high-elevation ice."

A net increase in mass.

[skinkinthegrass]

Are there no asteroids...for the next 76,000 years?

Yup, those NEOs.
....the ones that go "bump" in the night, are the ones that'll get us....
C'mon, I was off by just two decimal point(s). :D

http://youtube.com/watch?v=9JSR_6qfXTg
http://www.youtube.com/watch?v=Loc8bpczZPY

[secretagent]

I saw that too. A gain above 1500 meters and a loss below 1500 meters, as far as the altimeters can see. The gains and losses average to a 5.4cm/yr gain. But note the marginal areas (more at the perimeter, where the greatest loss rates occur?) :

The trend below 1500 metres however does not include the steeply-sloping marginal areas where current altimeter data are unusable.

This might mean that the loss of 2cm/yr in the below 1500 meters areas the satellite can measure, along with the marginal areas, roughly balances the 6.0cm/yr gain in the interior (above 1500 meters).

Hence the article's "no consensus" and "need for further data". Or in the words of the study's author:

"There is clearly a need for continued monitoring using new satellite altimeters and other observations, together with numerical models to calculate the Greenland Ice Sheet mass budget," Johannessen added.

[jwalsh07]

The one thing we know for sure is that Mother Earth never remains in stasis. If she slows down the bears gonna catch her.

[Matchett-PI]

I think you'll find it quite interesting. Here's some info on Crichton's credentials:

Bio: CRICHTON, (John) Michael. American. Born in Chicago, Illinois, October 23, 1942. Educated at Harvard University, Cambridge, Massachusetts, A.B. (summa cum laude) 1964 (Phi Beta Kappa). Henry Russell Shaw Travelling Fellow, 1964-65. Visiting Lecturer in Anthropology at Cambridge University, England, 1965. Graduated Harvard Medical School, M.D. 1969; post-doctoral fellow at the Salk Institute for Biological Sciences, La Jolla, California 1969-1970. Visiting Writer, Massachusetts Institute of Technology, 1988.

[secretagent]

Thanks for the cut and paste ping pong:) I learned something.

I can piss off either side now.

[jwalsh07]

LOL, you bet!

[staytrue]

Are these the same people who failed to accurately predict the number of hurricanes and tropical storms during this past hurricane season

No they are not and this is irrelevant to the argument at hand.

[staytrue]

And did these morons, I mean 'scientists', ever consider that the increase cloud cover will reflect more sunlight and decrease the effects of global warming.

Actually, clouds are the most effective of the greenhouse gases. If you want a warm winter night or a really mugged unbearable summer night, there is nothing like cloud cover to do the trick.

I would not go around calling people morons unless you are sure you know what you are talking about.

[_Jim]

Global warming is NOT a hoax. It's real.

Where's your proof?

Just because 'station records' near urban areas show warming DOES NOT mean so-called 'global;' warming is occurring ...

Foor instance, balloon and Microwave Sounding Units do not indicate this 'global' phenom.

[_Jim]

Global warming is a fact,

See my previuous post; you, too, have been taken in and have failed to do your homework.

[ancient_geezer]

Water vapor is indeed the most effective and most active greenhouse agent by far.

Clouds OTOH, operate to counteract conversion of visible spectum into heat at the surface by reflecting radiant energy back towards space.

Low cloud layers induce net cooling as both daytime solar radiation and atmospheric heat in the form of IR above clouds, are reflected upward to space.

A consequence of that reflectivity is that night time losses in the heat balance are not made up in the daytime influx of solar energy interacting at the surface which would otherwise heat the greenhouse gas components in the atmosphere.

High altitude ice clouds also act as a very efficient reflector of visible solar spectrum again inducing net cooling at the surface by intercepting incoming solar energy that sets thermal equilibrium of the atmosphere.

Cloud interactions are very complex and poorly accounted for in current climate models. Therein lay the weakest links in the Global Warming rationale.

[_Jim]

I agree we do have Global Warming

Provide/cite your 'proof'; avoid the use of data from those weather recording stations which have seen urban encroachment, have failed to have the trees and bushes in the vicinity maintained and trimmed back SUCH THAT the recording/measurement structure has an un-obstructed view of the open sky ...