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There has been some speculation about this since yesterday, but Paolo has confirmed that the first puddles of melted snow can be seen on images of NOAA's Arctic StarDot NetCam #1 that is located at the North Pole:
NOAA webcam 2 is also showing some dark patches:
This is a few days earlier than last year, and according to this NOAA webpage the earliest date since they began deploying the webcams on a yearly basis:
Now that the formidable ice plug in Smith Channel has finally broken up (see this blog post from a few days ago) the rest of the ice in Nares Strait gets a chance to start moving.
The coming days a high pressure system is forecast to roam the area, meaning 1) high temperatures and insolation that will further fragment the ice, and 2) clear skies that should deliver nice, clear MODIS images of the event. So the coming weeks I will update this animation that shows the whole of Nares Strait.
As always I advise to focus on one part of the animation, instead of trying to take it all in at once.
It's been over a year since this blog saw the light of day. We have now over 1 year of collective experience and learning under our belt, so I think an overview containing the most interesting articles and animations of the past year is appropriate. It's also a reference for comparison with this year's events.
June 7th 2010: the introduction to this blog, Welcome to this blog!, was written on this date. I still stand behind it, so if you want to know why I started this blog, I suggest you read it. The same goes for a subsequent piece called The Alarmist's Dilemma, written a week later.
During the melting season I'm regularly writing updates on the current sea ice extent (SIE) as reported by IJIS (a joint effort of the International Arctic Research Center and the Japan Aerospace Exploration Agency) and compare it to the sea ice extents in the period 2005-2010. NSIDC has a good explanation of what sea ice extent is in their FAQ. I also look at other things like sea ice area, concentration, volume, temperature and weather forecasts, anything that can be of particular interest. Check out the Arctic sea ice graph webpage for daily updated graphs, maps and live webcam images.
June 17th 2011
I'm never going on a holiday during the melting season again. It's amazing how much everything can change in just two weeks.I've been so busy catching up that I need another holiday.
In the last SIE update 3 weeks ago I was wondering if the 11 million mark would be passed before the end of the month for the first time (it didn't), and now the 10 million mark has been passed on the earliest date in the IJIS dataset.
Having a look at my spreadsheet helps a lot to see what has happened (first century breaks have been rolling in, more on that in a separate blog post in a couple of days), but I really miss the PIPS ice displacement forecast maps to see how the ice has moved these past couple of weeks. Luckily (and gratefully) I was able to glean a lot of info from the many comments that were posted during my absence.
Apparently weather conditions shifted yet again, slowing things down on the Canadian side - notably the Beaufort Sea where sea ice is no longer churned away towards Russia under the influence of the Beaufort Gyre - but wreaking havoc on the Siberian coast. This is resulting in serious drops in SIE and SIA.
Sea ice extent (SIE)
Here's the IJIS SIE graph:
If you click for the larger version you can actually see a pinch of white between this year's trend and the one from 2010, which was doing some pretty awesome stuff last year. This year could be awesomer, at least during June.
The current difference between 2011 and the other years is as follows:
It looks like I'm back just in time to witness the breaking up of the ice plug in Kane Basin. This just in from the Aqua satellite:
It's a bit vague, but it looks as if the lower part of the plug is crumbling. If it is breaking up, how long will it take for ice transport to get going through Nares Strait?
This page will be updated the coming few days. Stay tuned...
As some of you have noticed the people at the Polar Science Center of the Applied Physics Laboratory of the University of Washington have been very busy upgrading their PIOMAS model. As stated on their website:
This time series of ice volume is generated with an updated version of PIOMAS (June-15,2011). This updated version improves on prior versions by assimilating sea surface temperatures (SST) for ice-free areas and by using a different parameterization for the strength of the ice. Comparisons of PIOMAS estimates with ice thickness observations show reduced errors over the prior version. The long term trend is reduced to about -2.8 103 km3/decade from -3.6 km3/decade in the last version. Our comparisons with data and alternate model runs indicate that this new trend is a conservative estimate of the actual trend. New with this version we provide uncertainty statistics. More details can be found in Schweiger et al. 2011. Model improvement is an ongoing research activity at PSC and model upgrades may occur at irregular intervals. When model upgrades occur, the entire time series will be reprocessed and posted.
They have also upgraded their graphs, such as the one that features on the Daily Graphs page, which now has error bars:
There has been another big drop since the last update at the beginning of May. How this relates to other years can be seen on the other upgraded graph:
It has been almost 3 months since I put up the poll widget in the right side bar. Now that the SEARCH Sea Ice Outlook has come out, containing the results of another poll conducted by Anthony Watts of the Wattsupwiththat blog, it seems to be a good time to do a first update on this our ASI blog poll.
The 300 votes mark has just been passed today and this is how the expectations break down in percentages:
According to my calculations this amounts to an average of 4.2 million km2. Mind you, this is a prediction for IJIS daily extent. The entries for the SEARCH Sea Ice Outlook are all based on NSIDC monthly extent (September average). If I remember correctly the difference is approximately 200K km2.
Method: I've calculated the number by multiplying the percentage number with the average of an option (for instance 'between 4.5 and 5 million' = 4.75). For 'more than 5.5 million km2' I've used 5.75 million km2, and for 'less than 4 million km2' I've used 3.75 million km2. I've added up all multiplications and divided the result by 100. This is the best statistical analysis you'll get from me!
What is interesting is that the result page also shows where voters come from:
I'm a week late to this particular party (and some others), but this is something we'll want to reference later on (just like we did last year in June and July). SEARCH has released its first Sea Ice Outlook report, to which several people or groups of people - mostly science professionals - submit their projections for the September 2011 arctic sea extent, based on NSIDC monthly extent values.
Here's the summary for this year's June report:
The 2011 June Outlook suggests a modest decrease for summer 2011. With 19 responses for the pan-arctic (and 7 for the regional outlook), including several new contributors, the June Sea Ice Outlook projects a September 2011 arctic sea extent median value of 4.7 million square kilometers (Figure 1). This compares to observed September values of 4.7 in 2008, 5.4 in 2009, and 4.9 in 2010. The range of values is 4.0 to 5.6 million square kilometers, but the distribution is skewed toward lower values, suggesting either persistent conditions or a substantial drop below 2008 and 2010 values and the long-term downward trend. The 2011 June Outlook differs from the 2010 Outlook by not including projections of major increases in extent. It is important to note for context that all 2011 estimates are well below the 1979–2007 September climatological mean of 6.7 million square kilometers.
And here's the figure showing all the projections:
As was already noted in one of the comment sections we see that Zhang has revised his projection down from 4.5 million to 4.1 million (it was 5.0 million two months back). Zhang was very close to last year's final result, using the PIOMAS model.
Another noteworthy thing is the inclusion of the projection of Anthony Watts and his commenters over at Wattsupwiththat, based on a poll held a few weeks back. On the one hand I commend them for making a verifiable projection, which isn't something they do often and when they do they are often wrong (like last year).
Continue reading "SEARCH 2011 Sea Ice Outlook: June report" »
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