Record Ice Loss in Arctic 2008

dohboi · Light Sweet Crude Joined: Dec 05, 2005 Posts: 1476

I have a question. While total ice coverage is important both for its role in albedo feedback and because it is so dramatic and visible, the really important long-term measurement shoule be of total ice mass.

Does anyone know of a reliable site that tracks or estimates some kind of total ice figure, ideally with easy-to-access comparisons with previous years?

I don't know what to make of the register article, but the snarky tone about GW coverage leads me to wonder about their objctivity here. Do they think satalite images have been doctored too? At some point that just get too conspiracy-theory sounding for me.

It would be interesting to hear a less biased account of why there are some differences in how various studies quantify ice coverage.

rockdoc123 · Light Sweet Crude Joined: May 16, 2005 Posts: 1715

One of the issues with ice sheet mass balance is there is a host of estimates out there, many based on the same dataset (satellites) with different analyses conducted. The results vary wildly from huge losses all the way to net gains for both Greenland and Antarctica. Even with the newest methods there are varying results. What this means is it is hard to jump to any conclusion until such time as a lot more work is done.
Heres some of the articles for Greenland and Antarctica for those interested.

Greenland:

Alley, R.B., Clark, P.U., Huybrechts, P. and Joughin, I. 2005. Ice-sheet and sea-level changes. Science 310: 456-460.

Cazenave, A. 2006. How fast are the ice sheets melting? Science 314: 1250-1252.

Chen, J.L., Wilson, C.R. and Tapley, B.D. 2006. Satellite gravity measurements confirm accelerated melting of Greenland Ice Sheet. Science 313: 1958-1960.

Johannessen, O.M., Khvorostovsky, K., Miles, M.W. and Bobylev, L.P. 2005. Recent ice-sheet growth in the interior of Greenland. Sciencexpress / www.sciencexpress.org / 20 October 2005.

Luthcke, S.B., Zwally, H.J., Abdalati, W., Rowlands, D.D., Ray, R.D., Nerem, R.S., Lemoine, F.G., McCarthy, J.J. and Chinn, D.S. 2006. Recent Greenland ice mass loss by drainage system from satellite gravity observations. Science 314: 1286-1289.

Rignot, E. and Kanagaratnam, P. 2005. Changes in the velocity structure of the Greenland Ice Sheet. Science 311: 986-990.

Zwally, H.J., Giovinetto, M.B., Li, J., Cornejo, H.G., Beckley, M.A., Brenner, A.C., Saba, J.L. and Yi, D. 2005. Mass changes of the Greenland and Antarctic ice sheets and shelves and contributions to sea-level rise: 1992-2002. Journal of Glaciology 51: 509-527.

Antartica:

Remy, F. and Frezzotti, M. 2006. Antarctica ice sheet mass balance. Comptes Rendus Geoscience 338: 1084-1097

Ramillien, G., Lombard, A., Cazenave, A., Ivins, E.R., Llubes, M., Remy, F. and Biancale, R. 2006. Interannual variations of the mass balance of the Antarctica and Greenland ice sheets from GRACE. Global and Planetary Change 53: 198-208

Velicogna, I. and Wahr, J. 2006. Measurements of time-variable gravity show mass loss in Antarctica. Sciencexpress: 10.1126science.1123785
Moore, P., and M. A. King (2008), Antarctic ice mass balance estimates from GRACE: Tidal aliasing effects, J. Geophys. Res., 113,

Van de Berg, W.J., van den Broeke, M.R., Reijmer, C.H. and van Meijgaard, E. 2006. Reassessment of the Antarctic surface mass balance using calibrated output of a regional atmospheric climate model. Journal of Geophysical Research 111

Velicogna, I. and Wahr, J. 2006. Measurements of time-variable gravity show mass loss in Antarctica. Sciencexpress: 10.

Davis, C.H., Li, Y., McConnell, J.R., Frey, M.M. and Hanna, E. 2005. Snowfall-driven growth in East Antarctic Ice Sheet mitigates recent sea-level rise. Sciencexpress

xironman · Tar Sands Joined: Mar 13, 2007 Posts: 36

The GFS has consistently been forecasting colder temps over the cap long term then flipping back to warmer in the short term. I wonder if the unusual amount of open water is throwing the model off.

Tanada

Tanada

Holy Crud, look at: Ice loss map (large)
compared to last years minimum: Next ice loss map (large)

and what do you see? Forget about the open water! The hard dark bulge we had over the Canadian Archepelligo last fall? That was all 2 or more year old multi season ice, most of it much older.

This year, today, half that area is 40 percent open water!

Either the multi season ice there has begun melting rapidly, OR more likely wind and currents have shifted it counter clockwise towards Greenland. Neither answer bodes well for the Multi-year ice balance after the end of the melt season in 2008 and the winter flushing process.
_________________
Always appeal to a man's enlightened self interest, you can trust him to look out for himself honestly, It's when you appeal to his Honor or the Common Good that he stops paying attention.

sjn

Exactly, Tanada. This is what we've been following all season. This is why the register piece was so utterly insane. Having a few iceburgs floating around isn't the same thing as having an ice cap!

GregWatson · Heavy Crude Joined: Jun 07, 2008 Posts: 132

GregWatson · Heavy Crude Joined: Jun 07, 2008 Posts: 132

Try this blinker for a better understanding of the ice cap melt as of 18 Aug 2008 versus the same time last year: Ice cap melt

Greg

TonisD

Well, the article sure did the trick. Half of the interwebz is buzzing with how the "data is falsified to keep the warming hysteria" going etc.

Really sad actually, if you think about it.

turmoil · Last edited by turmoil on Tue Aug 19, 2008 8:26 pm; edited 1 time in total

Tanada

dohboi · Light Sweet Crude Joined: Dec 05, 2005 Posts: 1476

Sorry to keep posting the same graph in its updated form, but as far as I can tell the tale of the tape graph shows that the last few days precipitous decline has now brought us pretty much to where we were last year at this time, which of course was an astonishingly drastic departure from the already troubling steady decline of the last few decades. I was really starting to hope that we might see at least some recovery of coverage if not total ice mass this year. Oh well. Crying or Very sad

tale

And this is about all I've been able to find in the MSM on this planet-shaking development:

ice loss

"There are four weeks left before the annual ice melting season officially ends in the Arctic. Last year, the melting tempo abruptly rose in August and September, and now the same thing appears to be happening.
...

Last fall, around a million square kilometers of ice disappeared in a few weeks. Koc said there's a real danger that with so much ice already melted away, it won't be possible to return to conditions earlier viewed as "normal."

As the ice melts, warmer sunlight warms up the seas. At the same time, warmer waters from the Gulf Stream are being pressed northwards.

The temperature of the Gulf Stream along the Norwegian coast has risen two degrees Celsius in the past 20 years, while the average air temperature around Svalbard has risen four to five degrees."

Tanada

Yup, we are slightly above the 2 million below average mark now and well below ev ery year except 2007 due to that fact.

While technically if melting stops today we are somewhat better off than a year ago, it is clear that even so the trend contuinues down for the decade.
_________________
Always appeal to a man's enlightened self interest, you can trust him to look out for himself honestly, It's when you appeal to his Honor or the Common Good that he stops paying attention.

dohboi · Light Sweet Crude Joined: Dec 05, 2005 Posts: 1476

Here's a troubling study I hadn't seen before. Has anyone seen anything in print on methane releases for this year?

methane

"Last year, a large international expedition that included oceanologists from Russia, Canada, the US, Britain, and Germany hd explored the entire Arctic coast and detected high concentrations of methane that exceeded the norm 1,000-fold. Researchers' opinion is that this may be connected with the disintegration of gas hydrates at the sea bottom, owing to a rise in the temperature of water and the atmosphere."

(My emphasis)

That's quite an increase. Does not bode well for the future of life on earth.

I can't imagine that there has been much of decrease this year, since most of the shallow waters, especially Beaufort Sea, have been ice free for at least as long as last year by now, if not longer.

How much more certain can it get that we are now in run-away GW mode?

Tanada

Right now both the Arctic and Antarctic are dropping in ice cover, a rare event to be sure, but as a result the world ice total chart HERE shows the world coverage total is now 2 million below average for this date.

What will it take to wake people up to these kind of changes inour long term ice cover? Does the Arctic have to be ice free and Greenland all melted or what?
_________________
Always appeal to a man's enlightened self interest, you can trust him to look out for himself honestly, It's when you appeal to his Honor or the Common Good that he stops paying attention.