As I mentioned earlier, I held the WUWT Sea Ice News feature a day so that I could including an expected press release from NSDIC. I’m glad I did. Here it is, including yet another zinger from NSIDC director Mark Serreze. – Anthony
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Oct 4 2010 Arctic sea ice extent falls to third-lowest extent; downward trend persists
This is a press release from the National Snow and Ice Data Center (NSIDC), which is part of the Cooperative Institute for Research in Environmental Sciences at the University of Colorado at Boulder.
This September, Arctic sea ice extent was the third-lowest in the satellite record, falling below the extent reached last summer. The lowest- and second-lowest extents occurred in 2007 and 2008. Satellite data indicate that Arctic sea ice is continuing a long-term decline, and remains younger and thinner than it was in previous decades.
“All indications are that sea ice will continue to decline over the next several decades,” said NSIDC Director Mark Serreze. “We are still looking at a seasonally ice-free Arctic in twenty to thirty years.”
Over the summer of 2010, weather and ocean conditions in the Arctic ranged from warm and calm to stormy and cool. Overall, weather conditions were not extremely favorable to melt, but ice loss proceeded at a rapid pace. NSIDC Scientist Julienne Stroeve said, “Sea surface temperatures were warmer than normal this summer, but not as warm as the last three years. Even so, the 2010 minimum rivaled that in 2008—this suggests that other factors played a more dominant role.”
—Credit: National Snow and Ice Data Center
The amount of old, thick ice in the Arctic continues to decline, making the ice pack increasingly vulnerable to melt in future summers. While there was an increase this year in second and third year ice, which could potentially thicken over the next few years, the oldest and generally thickest ice (five years or older) has now disappeared almost entirely from the Arctic. This September, less than 60,000 square kilometers (23,000 square miles) of five-year-old or older ice remained in the Arctic Basin. In the 1980s an average of 2 million square kilometers (722,000 square miles) of old ice remained at the end of summer. “While the total coverage of multiyear ice is the third lowest on record, the amount of younger multiyear ice has rebounded somewhat over the last two years. A key question is whether this ice will continue to survive over the next couple of summers, perhaps slowing the overall decline in multiyear ice area,” said James Maslanik, a research professor in the Department of Aerospace Engineering Sciences at the University of Colorado, who provided the ice age data.
—Credit: National Snow and Ice Data Center
Arctic sea ice extent on September 19, the lowest point this year, was 4.60 million square kilometers (1.78 million square miles). Averaged over the month of September, ice extent was 4.90 million square kilometers (1.89 million square miles) (Figure 1). This places 2010 as the third lowest ice extent both for the daily minimum extent and the monthly average. Ice extent fell below 2009 and was only slightly above 2008 (Figure 2).
After September 10, ice extent started to climb, apparently signaling the end of the melt season. However, uncharacteristically, it then declined again, until September 19. “The late-season turnaround indicates that the ice cover is thin and loosely packed—which makes the ice more vulnerable both to winds and to melting,” said Walt Meier, NSIDC research scientist.
Arctic sea ice follows an annual cycle of melting and refreezing, melting through the warm summer months and refreezing through autumn and winter. Sea ice reflects sunlight, keeping the Arctic region cool and moderating global climate. While Arctic sea ice extent varies from year to year because of changeable atmospheric and ocean conditions, ice extent at the end of the melt season has shown a significant overall decline over the past thirty years. During this time, September ice extent has declined at a rate of 11.5 percent per decade during September (relative to the 1979 to 2000 average) (Figure 3), and about 3 percent per decade in the winter months.
—Credit: National Snow and Ice Data Cente
More Information
For further analysis and images, please see the related October post on Arctic Sea Ice News & Analysis Web site (http://nsidc.org/arcticseaicenews/)
For a full listing of press resources concerning Arctic sea ice, including previous press releases and quick facts about why and how scientists study sea ice, please see “Press Resources” on the NSIDC Arctic Sea Ice News & Analysis Web page.
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Source: http://nsidc.org/news/press/20101004_minimumpr.html
Well I hope I’m around in 30 years to look up Dr. Serreze.
Arctic Sea Ice is making a quick turnaround, the DMI 30% graph shows we are now at 2005 levels for 30% extent.
Have a look at this interesting animation showing the quick turnaround in ice extent in September…
Steve Goddard writes:
Blink comparator showing ice growth over the past week. More than 5,000 Manhattans of new ice have formed – one new Manhattan of ice every two minutes.
http://arctic.atmos.uiuc.edu/CT/animate.arctic.color.0.html
The JAXA 15% extent graph shows a similar sharp turnaround.
…and a close up view shows that we are now slightly ahead of this date last year:
And 80N+ temperature remains close to climatology:
The Northwest passage appears to be fully closed:
So, in a nutshell, things are icing up quickly. 2011 looks to be interesting!
Don’t forget to check status at the WUWT Sea Ice Page.
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EFS_Junior says:
NOPE!
“The linear downward trend for Arctic sea ice extent (NSIDC monthly means) started in 1984 …”
“The linear downward trend for Arctic sea ice area (NSIDC monthly means) started in 1981 (area)”
==============================
Started in 1984?
OK even earlier….in 1981.
1981 – 2010 = 29 years
4.6 billion / 29 = 158,620,690
Drop in the bucket.
Chris
Norfolk, VA, USA
OMG OMG the sky is falling the sky is falling the ice is melting the ice is melting…the world is ending the world is ending.
-Chris
Norfolk, VA, USA
A few minor corrections to my last post;
“This works …” refers to linear and polynomial least squares regressions.
R^0.95 should be R^2 = 0.95 and R^0.93 should be R^2 = 0.93
In the last sentence “(2030-2040)” refers to when the extrapolation crosses the x-axis (zero) (and similarly for “(2020-2030)”).
savethesharks says:
October 4, 2010 at 10:40 pm
EFS_Junior says:
NOPE!
“The linear downward trend for Arctic sea ice extent (NSIDC monthly means) started in 1984 …”
“The linear downward trend for Arctic sea ice area (NSIDC monthly means) started in 1981 (area)”
==============================
Started in 1984?
OK even earlier….in 1981.
1981 – 2010 = 29 years
4.6 billion / 29 = 158,620,690
Drop in the bucket.
Chris
Norfolk, VA, USA
OMG OMG the sky is falling the sky is falling the ice is melting the ice is melting…the world is ending the world is ending.
-Chris
Norfolk, VA, USA
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The start year where the linear slope stays negative for N consecutive years.
1981-2010 includes both 1981 and 2010 (and all years in between), therefore N = 30.
“The estimated age of the universe is 13.75 ± 0.17 billion years,”
Hmm …
13.75E9/30 = 458,333,333
Don’t know what the heck that means with respect to TODAY and the next few decades though, you know like O(1).
It’s interesting to see the arctic ice volumes from PIPS 2.0 (the erstwhile Steve Goddard’s favourite dataset). Unlike Steve, I’ve correctly included concentration as well as thickness in the following plots. On the basis of his erroneous sums, Steve predicted 5.5 M km^2 for the ice extent. A little more cautiously I said 2010 would “probably be below 2009” which would make this year the second lowest volume. Here are the PIPS 2.0 volumes for the last three months:
http://img196.imageshack.us/img196/82/melt2006to10.png
and the PIPS 2.0 September volumes since 2002:
http://img215.imageshack.us/img215/7825/septemberminsfrom2002.png
2010 just beat 2009 in terms of volume.
Certainly PIPS 2.0 shows a much slower volume loss this year than might have been extrapolated from the dataset up to 2008, but hardly a recovery. It will take a few more years of proper data (PIPS 2.0 is model output anchored to SSMI ice areas, not real volume measurements) to see whether the Arctic ice might be at risk of complete summer loss over timescales of a few years, or a few decades.
I’ll post the code for getting these volumes from PIPS if anyone’s interested.
Originally looked at this page at the Geological society for the Joe Brannan reply to a Bob Ward letter but if you scroll down to ‘Glaciers again – when will they collapse?’ there are a few letters of interest from other Geological society members, real scientists not politicians.
http://www.geolsoc.org.uk/gsl/op/www.g%3C/views/letters
Wasn’t it Sereze who said the summer ice woud be gone by 2015 and nearly so by 2013?
How does 2010 compare to 1979-2009 as opposed to stopping short at 2000?
2010 the third lowest ice cover? If there is a recovery from a record low, regardless of the length of that ‘record’ then following years will be down the list from the record.
Saying that it is the third lowest proves nothing especially if there is a record refreeze.
As I suspected NSIDC has glossed over the facts with their spin on the facts.
I wonder if Frank makes an interesting point: nothing very much seems to happens to ice extent between 1979 and about 1998, despite this being (I am happy to accept) a time when temperatures, on average, rose quite quickly. Since then, temperatures seem to have been pretty flat, whereas, ice extent fell quite sharply.
The obvious first question to investigate, it seems to me, is whether thermal inertia largely explains what is going (or went) on. Simply put, a build up of heat in the 80s and 90s resulted in an eventual decrease in ice extent in the noughties. Perhaps in the last couple of years, we have seen that build up of heat exhaust itself, and the relatively flat temperatures of the last 10+ years will result in the ice extent stabilising or even “recovering”?
It would be a shame if explosively-enforced paradigms discouraged scientists from asking interesting questions.
Scott says:
October 4, 2010 at 3:18 pm
“Does anyone have a good explanation?”
We know from the Satellitegate fiasco that the measurement systems are prone to degradation over time and that the data itself is poorly managed. Not easy to get good quality consistent data from different sources – it’s a travesty!
bateman says:
October 4, 2010 at 5:34 pm
“How exactly does science determine from the wiggling Sea Ice Minimums when a corner is turned and when the trend will continue out in a straight-line fall?
Time for some test cases. Just pick a couple of sets of cyclic data, making sure to catch the start of a decline, and cut it off somewhere before it changes back up. Have statistics attempt to predict which sets are about to turn, and which sets will continue on down.”
Thanks Rob for a good explanation of why trying to use linear trends on data taken from quasi-cyclical system driven by deterministic chaos is a fruitless exercise.
People like NSIDC director Mark Serreze must know of this problem, yet they still foist this rubbish on the public.
Ice loss was so bad this year that they were able to find the wreck of HMS Investigator, that sank whilst searching for the North West Passage in 1853. As ice loss has never been so bad before, clearly HMS Investigator must have been dropped through the ice by an alien space ship How else could it have got there, it can’t have broken through ice under sail power. What other explanation is there?
Good to see that intrepid UK adventurer Bear Grylls made it through the NWP this year in a powerful RIB. His start was delayed due to mother nature. ??? Don’t know what that means? Success depended on their ice breaking support ship. So it wasn’t that clear of ice then?
When Columbus discovered America, he had a map. Someone had been there before. When Captain Cook discovered Australia, he had a map. Someone had been there before.
100’s of people perished in the search for the North West Passage. Was it because they knew it was there, that someone had been there before. They had a map?
The problem with using 15% as a measure of sea ice extent is, I believe, flawed.
Because of the large amount of space between chunks of ice at 15%, then dependent only on currents and winds there is a theoretical possible approx 6:1 ratio of total ice coverage from its loosest to its tightest packing.
The 30% measure improves the situation, but the possible variation is still large in comparison with the year to year variations we are being asked to believe are a measure of whether the arctic is melting or freezing.
Discussions of temperature (sea or air) would seem to be meaningless in the context of arctic ice coverage if the effects of wind and current cannot be isolated.
I suspect that the sudden drop in extent in September is more likely to be caused by wind shift causing packing rather than actual ice melting, especially given ambient temperatures at the time (I am assuming here that could not have been a rapid rise in sea surface temperature at the time).
If this is indeed the case then it is intellectually dishonest of NSDIC not to mention the possibility, and of course forecasting future arctic ice behaviour would depend on the ability to predict wind patterns years in advance.
I know that somehow the summer of 2010 in the Northern Hemisphere is going to be touted as “the hottest ever”. If so, why wasn’t the ice loss worse?
TomRude says:
October 4, 2010 at 3:49 pm
If not for only a short 2-3 week period in september, 2010 would have been virtually identical to 2009, despite an El Nino year! Alarmism is not backed by facts…
______
“If not for…” statements are excuses. It was what it was, and the facts say that the Arctic has not seen a positive sea ice anomaly since 2004. Dems da facts…and “if not for…” statements are meaningless.
Tom P says:
October 5, 2010 at 12:22 am
It’s interesting to see the arctic ice volumes from PIPS 2.0 (the erstwhile Steve Goddard’s favourite dataset). Unlike Steve, I’ve correctly included concentration as well as thickness in the following plots. On the basis of his erroneous sums, Steve predicted 5.5 M km^2 for the ice extent. A little more cautiously I said 2010 would “probably be below 2009″ which would make this year the second lowest volume. Here are the PIPS 2.0 volumes for the last three months:
http://img196.imageshack.us/img196/82/melt2006to10.png
and the PIPS 2.0 September volumes since 2002:
http://img215.imageshack.us/img215/7825/septemberminsfrom2002.png
2010 just beat 2009 in terms of volume.
Certainly PIPS 2.0 shows a much slower volume loss this year than might have been extrapolated from the dataset up to 2008, but hardly a recovery. It will take a few more years of proper data (PIPS 2.0 is model output anchored to SSMI ice areas, not real volume measurements) to see whether the Arctic ice might be at risk of complete summer loss over timescales of a few years, or a few decades.
I’ll post the code for getting these volumes from PIPS if anyone’s interested.
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Good job.
I for one, would be very interested in the (your) code.
I’ve started the reverse engineering of the PIOMAS charts and would like to compare their model data for total Arctic sea ice volume with the PIPS 2.0 model data (assimilated correctly by cross-integration of the thickness and concentration PIPS images and if you then converted these to actual engineering units (km^3) vs “pixel-metres”).
Something SG needed to do, to see if PIPS was/is conservative (gives higher volumes and by how much on average and seasonally (bi-monthly)) than PIOMAS.
If you need an email address, I have “dump side” email address that I’m willing to post here (I only read it if there is something that I request from someone else in particular).
Scott says:
October 4, 2010 at 3:18 pm
Okay, so I’ve brought up a question a few times before, but it wasn’t really pressing then. Now now the discrepancy has become a lot more apparent, so I’ll bring it up again:
Just watts up with the DMI plot? DMI 30% extent has topped both 2005 and 2009 now. But JAXA 15% extent has 2010 being 57k above 2009 and 106k below 2005. CT area has 2010 about 40k below 2009 right now and a whopping 696k below 2005, which is absolutely huge.
I expect 30% extent to behave somewhere between area and 15% extent, so the 2009 comparison numbers are reasonable, but the 2005 numbers seem way out there. I know there’s a good deal of uncertainty in area measurements, but can that really explain this discrepancy? I don’t think so…
Does anyone have a good explanation?
-Scott
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Scott,
I’m going to try to answer your question by posting a bunch of numbers (three significant digits, all values in millions of km^2).
For 10/1/2010 (rows are (1) Site, (2) Area or Extent, and (3) Concentration);
Norsex UIUC DMI JAXA NSIDC Bremen Norsex
5.12 4.01 4.64 5.67 5.53 5.65 6.47
100% 100% 30% 15% 15% 15% 15%
For the same date in 2005 and 2009;
Date UIUC DMI JAXA
2005 4.71 4.56 5.86
2009 4.05 4.40 5.75
(if these show up as single spaced, I can repost with commas to eliminate any confusion)
1) For 2009, DMI data appears to be “bad” for the period 10/1/2009 thru 10/18/2009, looking closely at this period there are too many vertical and horizontal lines of pixels, that do not show up elsewhere in their graphic.
2) However, the above does not explain why, for 10/1/2010, DMI shows a larger number of 4.64 (30%) vs UIUC of 4.01 (1005).
3) With the exception of JAXA, NSIDC, Bremen (all three 15%), and UIUC (100%), the other datasets (Norsex and DMI) must be considered “self-contained” meaning their numbers are good for comparison within each record itself. I have much more to say with respect to DMI and Norsex, and would like to discuss them in a follow-up post.
4) I find the extents and area statistics for JAXA, NSIDC, Bremen, and UIUC for the last 40 days (ending 10/3/2010) as (mean and standard deviation (to four signidicant digits));
NSIDC,4.963,0.262
Bremen,5.013,0.231
JAXA,5.165,0.232
UIUC,3.383,0.293
Note the differences in the mean extents for the first three (15%).
5) Most all my data efforts have been between UIUC, NSIDC, and JAXA. This is ongoing work, as I want to mix and match correctly between these three datasets.
I would like us to continue this dialog, as I think it would benefit both of us, and perhaps, the wider WUWT community at large.
Respectfully,
Junior
EFS_Junior,
“Serreze almost nailed it, the last sentence should read;
“We are still looking at a seasonally ice-free Arctic in ten to twenty years.”
==================
Right. So if in twenty years the ice is still the same as today, will you publicly admit that you were wrong?
Peter Plail says:
October 5, 2010 at 5:13 am
The problem with using 15% as a measure of sea ice extent is, I believe, flawed.
Because of the large amount of space between chunks of ice at 15%, then dependent only on currents and winds there is a theoretical possible approx 6:1 ratio of total ice coverage from its loosest to its tightest packing.
The 30% measure improves the situation, but the possible variation is still large in comparison with the year to year variations we are being asked to believe are a measure of whether the arctic is melting or freezing.
Discussions of temperature (sea or air) would seem to be meaningless in the context of arctic ice coverage if the effects of wind and current cannot be isolated.
I suspect that the sudden drop in extent in September is more likely to be caused by wind shift causing packing rather than actual ice melting, especially given ambient temperatures at the time (I am assuming here that could not have been a rapid rise in sea surface temperature at the time).
If this is indeed the case then it is intellectually dishonest of NSDIC not to mention the possibility, and of course forecasting future arctic ice behaviour would depend on the ability to predict wind patterns years in advance.
_____________________________________________________________
You go with what you can easily get with respect to available end products.
You also forgot to mention SST vs air temperatures.
I don’t think we can say with 100% certainty that it was 100% wind or 100% SST.
It’s a combination of both and a matter of degree.
So, for example, air temperatures drop below freezing, but SST remain above freezing (of either freshwater or saltwater). Surface melt stops, but subsurface melt continues, until the time when vertical overturning occurs, both locally and regionally, then basin-wise.
You should look at the Extent/Area ratios as a weak proxy for sea ice volumes, using JAXA and UIUC data, in that you will see a distinct difference between 2002-2006 vs 2007-2010.
It really is much more about sea ice volume than it is area or extent.
The sea ice volume setup for 2011 does not look good, particularly if a lot of MYI is flushed out of the Fram Strait this fall/winter.
The PIOMAS model indicates a new record low for 2010 at ~4E6 km^3 in September, and I believe that’s the 4th straight record breaker in the PIOMAS modelled sea ice volume;
“Monthly average Arctic Ice Volume for Sept 2010 was 4,000 km^3, the lowest over the 1979-2010 period, 78% below the 1979 maximum and 9,400 km^3 or 70% below its mean for the 1979-2009 period.”
A “small” correction to my last post;
“… a new record low for 2010 at ~4E6 km^3 in …”
should be;
“… a new record low for 2010 at ~4E3 km^3 in …”
per the PIOMAS website.
I’m thinking that we will see a slowdown in ice growth till this weekend when I think it will spike up again (just looking at weather & stuff)..Speaking of weather… After 24 inches of rain from Mother natures heat release plan which zapped us into fall we got it goin on down here in the Carolinas..Fish on!
OH & Also…1st Snow above 4000′ in the WV Alpps today & the earliest snow up at Mt Lacont,NC in 30 years…Who’s afraid of the big bad GW?..
Another correction in my reply to Scott;
“2) However, the above does not explain why, for 10/1/2010, DMI shows a larger number of 4.64 (30%) vs UIUC of 4.01 (1005).”
should read;
“2) However, the above does not explain why, for 10/1/2005, DMI shows a smaller number of 4.56 (30%) vs UIUC of 4.71 (100%).”
Sorry for all these corrections. 🙁
EFS_Junior
Thanks for the comments – however did mention SST but suggested it would not have changed rapidly enough to caused a large drop in extent over a short time period. I would expect the effect of SST changes to have a smooth rather than abrupt changes in extent.
I agree that volume is a better indicator of the health of the Arctic; as you observe extent is a poor proxy. Essentially what I failed to make clear is that extent is more susceptible to changes over the short term due to wind packing/unpacking effects (because, for example wind direction can change by up to 180degrees in a short time) than air or even more so SST. The short term effect of wind on volume is negligable without an accompanying change in air temperature except when it continues in one direction long enough to drive ice out. As you say, the outlook is poor for arctic ice if the wind, and not AGW effects, flush ice out through the Fram Straits. Which brings me back to the point, the wind seems to be a major influencer of ice mass in the Arctic, a point which NSDIC doesn’t seem to want to highlight.
EFS_Junior,
Thanks for the in-depth postings. I’m really busy now, and will be for a while, but I’ll try to address your comments as soon as I can. Just remember that you seem to have a good deal more statistical expertise than I do.
Thanks again,
-Scott