What do you think of this year's Arctic sea ice melt?

I think maybe of more interest than the total ice melt is that its timing was different this year, with there being much more ice lost in later in the summer than observed in the past. Coupled with the fact that most estimates claim that only about 1/3 of the observed warming in the arctic can be attributed to the direct radiative forcing from anthropogenic greenhouse gases (although I have heard it argued that short-lived anthropogenic species might be responsible for warming not due to GHGs), it suggests there are some fairly radical changes in climate going on in the arctic.

What people probably should be taking away from this is not so much the total ice loss (or recovery for that matter) each season, but the change in dynamics. For those who are clued in scientifically and understand why "climate change" is a more appropriate term than "global warming" for what is happening, the change in arctic climate provides a great example of what are termed "nonlinearities" in the system. Of course, if you are of the mindset that believes "climate change" was chosen for purely political reasons, then anything that deviates from a one-to-one correlation between rising CO2 levels and uniform temperature increase over the planet only indicates that the whole theory is wrong.

The first reference gives the 1979 to 2000 average as a comparison to 2007 and 2008. I think that the graph would be more informative if all of the curves were plotted, or at least the standard deviations on the average. The second source implies that the SD is about 1/4 of the signal, but these are annual averages so the numbers cannot be directly compared without accounting for seasonal effects. The June ice extent may be within the SD for the average, but it would appear that the September ice extent in recent years is significantly outside a SD for the average. A better, but perhaps more difficult measurement would be the ice volume rather than area.

The increasing arctic ice melt indicates more energy is arriving in the arctic. I think that the relative contributions of a change in albedo and energy flux from lower lattitudes (via ocean currents) to the excess energy is an open question.

Its up 13% on last year and at the end of summer, thats an area the size of germany recovered. According to shipping reports the ice is not navigatable without an ice breaker, which suggest the satelite is not correctly reading the new thin ice mass (this is a known issue with the satelites, compare NASA and UIUC and there are discrepancies). Satellite images show its nowhere near being an island and if you look over previous images it has had a similar ice mass as today 20 odd years ago (though again, the statelites often fail to pickup the thinner new ice so a accurate comparison is not really possible between any year).

Its not the second lowest in recorded history, in geological terms ice at the poles is a rarity only having occured for around 10% of history. In more recent times the poles were navigatable during the 1920's and 1930's, this is well documented.

This is proof nothing other than a natural cycle and it is caused by a warm current passing through the area, not warming of the atmosphere. Air temperature does not melt the ice at the north pole (average temp -26), the sea does and the sea has a temperature memory of thousands of years.

Also according to climate scientists warming should increase ice mass due to increased precipitation and cloud cover which cools the poles further, as has been observed in the southpole.

Its a classic case of scare mongering, nothing more, can we please hear about the growing ice mass of the antarctic instead?

Not surprising. Like what the proponents were going on about earlier this year, new ice is thinner, making for an easier melt. I haven't really seen a temperature record for the Arctic, and how La Nina effects us down here really means nothing in the Arctic. Meier said warm ocean waters made a large contribution to this melt, so obviously it was warmer up there.

What I think is: We are still learning about the planet we live on. The first sentence you copied and pasted to your question says a lot in just a few small words at the end of it: "since the dawn of the satellite era".

I also feel since it appears air temperature doesn't have as much effect on the Arctic as otherwise thought (This learned due to the fact it was colder up there this year than it was in recent years.) So we know other things are at play here, like the Pacific and Atlant ocean. Since it melted more on the Atlantic side this year then it did on the Pacific I'd say the Atlantic ocean was warmer this year than the Pacific ocean.

You can see it in these Satellite images:

http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh?...

The Pacific ocean has cooled even more this summer:

http://jisao.washington.edu/pdo/

http://tamino.wordpress.com/2008/05/27/pdo-the-pac...

http://earthobservatory.nasa.gov/Newsroom/NewImage...

So even though the Arctic didn't rebound as much as I was hoping it would this year, I'm not as pessimistic about it as the person who wrote the blog you quoted.

With the Pacific ocean cooling off I expect we will see more rebounding of the ice on a yearly basis. Also since these PDO patterns can last along time, any where from 30 to 70 years, we could be in for a major cool down that could last not only the rest of my lifetime, but the rest of yours as well.

Now I'm watching how quickly the ice reforms this year, since the faster it does the thicker it will get this winter, so I'm watching for the true minimum.

http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh?...

http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh?...

From Anthony Watts blog:

We have news from the National Snow and Ice Data Center (NSIDC). They say: The melt is over. And we’ve added 9.4% ice coverage from this time last year. Though it appears NSIDC is attempting to downplay this in their web page announcement today, one can safely say that despite irrational predictions seen earlier this year, we didn’t reach an “ice free north pole” nor a new record low for sea ice extent. Here is the current sea ice extent graph from NSIDC as of today, notice the upturn, which has been adding ice now for 5 days:

Here is what they have to say about it: “The Arctic sea ice cover appears to have reached its minimum extent for the year, the second-lowest extent recorded since the dawn of the satellite era. While above the record minimum set on September 16, 2007, this year further reinforces the strong negative trend in summertime ice extent observed over the past thirty years. With the minimum behind us, we will continue to analyze ice conditions as we head into the crucial period of the ice growth season during the months to come.

Despite overall cooler summer temperatures, the 2008 minimum extent is only 390,000 square kilometers (150,000 square miles), or 9.4%, more than the record-setting 2007 minimum. The 2008 minimum extent is 15.0% less than the next-lowest minimum extent set in 2005 and 33.1% less than the average minimum extent from 1979 to 2000.

Determining with certainty when the minimum has occurred is difficult until the melt season has decisively ended. For example, in 2005, the time series began to level out in early September, prompting speculation that we had reached the minimum. However, the sea ice contracted later in the season, again reducing sea ice extent and causing a further drop in the absolute minimum.

We mention this now because the natural variability of the climate system has frequently been known to trick human efforts at forecasting the future. It is still possible that ice extent could fall again, slightly, because of either further melting or a contraction in the area of the pack due to the motion of the ice. However, we have now seen five days of gains in extent. Because of the variability of sea ice at this time of year, the National Snow and Ice Data Center determines the minimum using a five-day running mean value.

In addition, NSIDC will issue a formal press release at the beginning of October with full analysis of the possible causes behind this year’s low ice conditions, particularly interesting aspects of the melt season, the set-up going into the important winter growth season ahead, and graphics comparing this year to the long-term record. At that time, we will also know what the monthly average September sea ice extent was in 2008 - the measure scientists most often rely on for accurate analysis and comparison over the long-term.”

It will be interesting to see what they offer in the October press release. Plus we’ll be watching how much ice we add this winter, and what next year�s melt season will look like. Hopefully we won’t have a new crop of idiots like Lewis Gordon Pugh trying to reach the “ice free north pole” next year.

“What do you think of this year's Arctic sea ice melt?”

Not a great deal really. There is significantly more ice at the North Pole this year compared to this time last year. http://igloo.atmos.uiuc.edu/cgi-bin/test...

You say this is “the second-lowest extent recorded since the dawn of the satellite era”. So that’s since 1978 then?

You give us a great story from planetsave.com.blog... Their banner reads “bringing you green news, commentary, and services”... probably not one of the better science sources you’ve offered.

Then you add... “However, the melt was the second greatest in recorded history”.

“Recorded history?” I think your history is a bit off. Any geologist will be able to help you out on this... but you don’t like to be told about the long history. The Medieval Warm Period is another piece of “recorded history” and you’d rather not hear about either, so I’ll keep this a bit more recent.

There was a guy trying to kayak to the North Pole to show how serious global warming was. He got as far as 80.52 degrees north before getting frozen into the ice (Sept 2nd) Here’s how far he got. http://maps.google.co.uk/maps/ms?f=q&hl=...

These people made it further north...

“The Arctic ocean is warming up, icebergs are growing scarcer and in some places the seals are finding the water too hot, according to a report to the Commerce Department yesterday from Consul Ifft, at Bergen, Norway.

Reports from fishermen, seal hunters and explorers, he declared, all point to a radical change in climate conditions and hitherto unheard-of temperatures in the Arctic zone. Exploration expeditions report that scarcely any ice has been met with as far north as 81 degrees 29 minutes”

Very clear evidence of global warming you might think... except that you’d need to check the date of the report... November 1922. http://docs.lib.noaa.gov/rescue/mwr/050/...

Explorers Nansen and Johansen also attempted to Kayak to the North Pole. They got past 82Deg North... in 1893 http://www.archive.org/details/farthestn... Read from page 244 onwards.

USS Seadragon and USS Skate rendezvous in open water at the North Pole. “Seadragon (SSN-584), foreground, and her sister Skate (SSN-578) during a rendezvous at the North Pole in August 1962. (see the men on the ice in the background)”

http://www.navsource.org/archives/08/0858411.jpg

Even in recent history, the absence of ice around the North Pole is not unusual. Read more about ocean circultation... warmer water melts ice much better than warmer air.

Dana, sorry mate, but the sceptics who were crowing just two months ago that 'the sea ice melt isn't as bad as 2007 therefore GW doesn't exist' are now saying 'two swallows don't make a summer'; they're in denial, that's why they are denialists.

Although there are a few real denialists/ostriches, most are sceptics who argue that all of these changes are 'normal'.

If all of these observable facts - the sea ice melt you mention plus spreading/changing range of flora and fauna, differing breeding and flowering patterns, melt back of alpine glaciers, etc, etc - are due to natural causes then we should be able to predict them.

I respectfully ask anyone who says that the level of change (as noted above) is natural/normal, to please tell us what the predictions are for natural/normal change over the next ten, twenty, fifty years?

We hear that everything is fine because 'New York used to be covered in ferns' or 'Greenland was like Italy' or some such; OK, if this is normal, what is Greenland, New York, Italy, Australia, wherever, supposed to look like in ten, twenty years if humans are NOT changing the climate?

That's the problem with your question - you are trying to get rational responses from irrational people!

I make of it that no matter what happened with sea ice this year, the AGW crowd would cherry-pick information that supports their cause and massage it into something to worry about.

Then you'd post it on here, and award points to whoever sucks up to you the best, telling that person what a caring genius they are.

"the second-lowest extent recorded since the dawn of the satellite era"

You mean since 1979?

You can't really use words like "unprecedented" and "record" when the "record" goes back 30 years.