Do you really believe the Arctic is melting as fast or faster than last year?

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Well really you're asking 2 seperate questions here.

1) Is the Arctic melting as fast or faster than last year?

So far, no.

http://nsidc.org/data/seaice_index/images/daily_images/N_timeseries.png

2) Does this mean the predictions of an ice free Arctic this summer are wrong?

Not necessarily.

You're assuming that there's a constant melt rate, and if we're behind last year's rate, we'll end the summer behind last year's melt extent. However, it's not a constant rate.

A key piece of information you're neglecting is that because of last year's record melt, the ice present now is mostly 1st-year ice, thinner than was present before; as a result, the new ice is more vulnerable to melting during the summer heat. So it's entirely possible that the melting will accelerate and the Arctic could become ice free by the end of the summer. Only time will tell.

Members of the Polaris Project, for example, are split 4-to-2 against this year’s record breaking last year’s.

http://thepolarisproject.org/blog/?p=25

Nice graphic showing their predictions:

http://thepolarisproject.org/blog/wp-content/uploads/2008/06/preds.png...Show more

Hmmm...
I did open the links and the first thing I read on the Cryosphere site is "The animation shows the dramatic loss of multiyear sea ice over the past year"
So, your own link says the ice is 'dramatically' less...!

The other site is quite interesting although, of course, very coarse - the scale is huge, it cannot show volume, etc. In other words, there is no quantitative data such subjective, but yes, still useful...

IF you want to base your entire statistical evaluation of the state of the arctic and past and present trends of melting on the comparision of ONE day ONE year apart!!

So, thanks, interesting, but not relevant to the discussion.

If you don't get what I mean, try looking at these links (the exact same site just comparing different days) that clearly show that the ice cap has shrunk (I more or less picked these days at random).
http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh?fm=07&fd=17&fy=1979&sm=07&sd=17&sy=2008
http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh?fm=02&fd=17&fy=2007&sm=08&sd=17&sy=2007
http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh?fm=10&fd=17&fy=2001&sm=10&sd=17&sy=2007

We could play this game for many years if you like - but the point is that comparing two days tells us nothing!

Edit reply:
Yes, I did open the first link that's the point - by comparing July 17 2007 to July 17 2008, all we can say is that the area of surface ice coverage on July 17 2008 is greater than it was one year ago: It's only one day!

Did you open my links? They also compare one day to another (OK, ignore the second one, I was being a smarta**e there) and they show ice cover shrinking.

Whether the ice cover is greater or lesser from one year to the next is irrelevant - we need multiple points or averages:
It just isn't scientifically relevant to compare two points and try to extrapolate a trend backwards or forwards....Show more

Who claims it is melting as quickly as it did last year?

Although this graph shows only area and not volume, it is a pretty clear indication that this years' melting so far has not been as extensive as last years': http://nsidc.org/data/seaice_index/images/daily_images/N_timeseries.png

It also shows there is less ice this year than what would be considered normal.

EDIT: How funny. I actually agree with Jello and I get a thumbs down while he gets a thumbs up. And I pointed out an obvious fact on the graph while he made a speculation.

EDIT: Actually, I DO remember when it was said the Arctic might be ice-free this year. That was speculation also....Show more

So far there is more ice coverage this year than last year's record low. It's a bit hard to judge from your image, but it's much clearer if you look at this plot

http://www.nsidc.org/data/seaice_index/images/daily_images/N_timeseries.png

It is still substantially below the 1979-2000 average extent. A tougher question is whether the volume of sea ice is greater. It appears that there is more first-year ice this year so it is thinner and will melt faster. Check out this image

http://www.nsidc.org/images/arcticseaicenews/20080717_Figure5.png

Anyway, we'll find out in a couple of months--of course if you'll remember back a couple of months, people were trying to convince us how much ice there was compared to normal--not just compared to last year....Show more

There's no way anyone who is honest can make the claim that the ice is melting faster this year.

The melting of the Arctic ice has slowed considerably this summer. There's a good chance that when winter comes around the ice will start forming at a greater area than during the 1979-2000 average....Show more