Earlier today in part1, I posted about the new record low claimed by NSIDC: Sea Ice News – Volume 3 Number 11, part 1 – new Arctic satellite extent record. The number given is 4.1 million square kilometers:
That of course is being trumpeted far and wide, new life has been given to Mark Serreeze’s “Arctic death spiral” in the media. But, here’s a curiosity, another NSIDC product, the new and improved “multi-sensor” MASIE product, shows no record low at ~ 4.7 million square kilometers:
Note the label at the bottom of the image in red. NSIDC doesn’t often mention this product in their press releases. They most certainly didn’t mention it today.
Another product, NOAA’s National Ice Center Interactive Multisensor Snow and Ice Mapping System (IMS) plot, also shows no reason for claiming a record at all:
Their number is (for 8/22) ~ 5.1 million square kilometers. (NOTE: NSIDC’s Dr. Walt Meir points out in comments that IMS and MASIE use the same base data, but that this one product from IMS only updates weekly, unlike all other sea ice plots which are daily. They should be in sync on the next update cycle, but right now MASIE and IMS should both be at 4.7 million sqkm. -A)
Another curiosity is here. On the NATICE interactive maps on demand page (click on Arctic Daily in the pulldown menu):
The numbers they give for 80% and marginal ice add up to an extent of 6,149, 305 square kilometers.
So who to believe? It depends on the method, and who thinks their method is most representative of reality. Measuring sea ice via satellite, especially when you use a single passive sensor system that has been show in the past to have degradation problems and outright failure (which I was told weren’t worth mentioning until they discovered I was right and pulled the plug) might be a case of putting all your eggs in one basket. I suspect that at some point, we’ll see a new basket that maybe isn’t so worn, but for now, the old basket provides a comfort for those who relish new records, even though those records may be virtual.
Note that we don’t see media pronouncements from NOAA’s NATICE center like “death spiral” and “the Arctic is screaming” like we get from its activist director, Mark Serreze. So I’d tend to take NSIDC’s number with a grain of salt, particularly since they have not actively embraced the new IMS system when it comes to reporting totals. Clearly NSDIC knows the value of the media attention when they announce new lows, and director Serreze clearly knows how to make hay from it.
But this begs the question, why not move to the new system like NOAA’s National Ice Center has done? Well, it is a lot like our July temperature records. We have a shiny new state of the art Climate Reference Network system that gives a national average that is lower for July than the old USHCN network and all of its problems, yet NCDC doesn’t tell you about the July numbers that come from it. Those tasks were left to Dr. Roy Spencer and myself.
In fairness though, I asked Dr. Walt Meier of NSIDC what he thought about MASIE, and this is what he wrote to me today:
It can provide better detail, particularly in some regions, e.g., the Northwest Passage.
However, it’s not as useful for looking at trends or year-to-year
variations because it is produced from imagery of varying quantity and quality. So the analyses done in 2007 have different imagery sources than this year. And imagery varies even day to day. If skies are clear, MODIS can be used; if it’s cloudy then MODIS is not useful. Another thing is that the imagery is then manually analyzed by ice analysts, so
there is some subjectivity in the analysis – it may depend on the amount of time an analyst has in a given day.
Our data is from passive microwave imagery. It is not affected by clouds, it obtains complete data every data (except when there may be a sensor issue), it has only consistent, automated processes. So we have much more confidence in comparing different days, years, etc. in our passive microwave data than is possible using MASIE.
Finally, MASIE’s mandate is to try to produce the best estimate they can of where there is any sea ice. So they may include even very low concentrations of ice <15%. In looking at visible imagery from MODIS, in the few cloud-free regions, there does appear to be some small concentration of ice where MASIE is mapping ice and our satellite data is not detecting ice. This is ice that is very sparse, likely quite thin. So it will probably melt out completely in the next week or two.
MASIE has tended to lag behind our data and then it catches up as the sparse ice that they map disappears. This year the difference between the two is a bit larger than we’ve seen in other years, because there is a larger area of sparse ice.
You can thank the big Arctic storm of August 4th-8th for that dispersal.
“The Great Arctic Cyclone of 2012″ effect on Arctic sea ice is seen in this before and after image:
Figure 4. These maps of sea ice concentration from the Special Sensor Microwave Imager/Sounder (SSMIS) passive microwave sensor highlight the very rapid loss of ice in the western Arctic (northwest of Alaska) during the strong Arctic storm. Magenta and purple colors indicate ice concentration near 100%; yellow, green, and pale blue indicate 60% to 20% ice concentration.
Credit: National Snow and Ice Data Center courtesy IUP Bremen
Trends -vs- records, just like July temperatures. One system might be better at trends, another might be better at absolutes used to determine records. In this case we have three other respected methods that show absolute values higher than that of NSIDC’s older method which they have a high confidence in. I suppose these systems are like children. In a competition, you always root for your children over the children of the other parents, so it is no surprise that NSIDC would root for their own well known media star “child” over that of NATICE’s IMS and NSIDC’s own lesser known child, MASIE.
Oh, and then there’s Antarctica, that other neglected ice child nobody talks about, with its above normal ice amounts right now:
No matter what though, its all just quibbling over just a little more than 30 years of satellite data, and it is important to remember that. It is also important to remember that MASIE wasn’t around during the last record low in 2007, and IMS was just barely out of beta test from 2006. As measurement systems improve, we should include them in the discussion.
UPDATE: Andrew Revkin reports on the issue in his Dot Earth article here
He’s a bit skeptical of the sound byte hype coming from NSIDC writing:
That’s one reason that, even with today’s announcement that the sea ice reached a new low extent for the satellite era, I wouldn’t bet that “the Arctic is all but certain to be virtually ice free within two decades,” as some have proposed. I’d say fifty/fifty odds, at best.
…
But is this a situation that is appropriately described as a “death spiral”? Not by my standards.
Revkin also takes Al Gore to task on Twitter:
help him out, retweet this
UPDATE2: Commenter Ron C. provides this useful information in comments that helps explain some of the differences and issues:
The main point is that NIC works with images, while the others are microwave products.
“Polar orbiting satellites are the only source of a complete look at the polar areas of the earth, since their orbits cross near the poles approximately every two hours with 12 to 13 orbits a day of useful visible data. This visible imagery can then be analyzed to detect the snow and ice fields and the difference in reflectivity of the snow and ice. By analyzing these areas each day, areas of cloud cover over a particular area of snow and ice can be kept to a minimum to allow a cloud free look at these regions. This chart can then be useful as a measure of the extent of snow and ice for any day during the year and it can also be compared to previous years for climatic studies.”
http://www.natice.noaa.gov/ims/snow_ice.html
“NIC charts are produced through the analyses of available in situ, remote sensing, and model data sources. They are generated primarily for mission planning and safety of navigation. NIC charts generally show more ice than do passive microwave derived sea ice concentrations, particularly in the summer when passive microwave algorithms tend to underestimate ice concentration. The record of sea ice concentration from the NIC series is believed to be more accurate than that from passive microwave sensors, especially from the mid-1990s on (see references at the end of this documentation), but it lacks the consistency of some passive microwave time series. ”
http://nsidc.org/data/g02172.html
Some have analyzed the underestimation by microwave products.
“We compare the ice chart data to ice concentrations from the NASA Team algorithm which, along with the Bootstrap algorithm [Comiso, 1995], has proved to be perhaps the most popular used for generating ice concentrations [Cavalieri et al.,1997]. We find a baseline difference in integrated ice concentration coverage north of 45N of 3.85% ± 0.73% during November to May (ice chart concentrations are larger). In summer, the difference between the two sources of data rises to a maximum of 23% peaking in early August, equivalent to ice coverage the size of Greenland.”
From Late twentieth century Northern Hemisphere sea-ice record from U.S. National Ice Center ice charts, Partington, Flynn, Lamb, Bertoia, and Dedrick
http://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1058&context=usdeptcommercepub
The differences are even greater for Canadian regions.
“More than 1380 regional Canadian weekly sea-ice charts for four Canadian regions and 839 hemispheric U.S. weekly sea-ice charts from 1979 to 1996 are compared with passive microwave sea-ice concentration estimates using the National Aeronautics and Space Administration (NASA) Team algorithm. Compared with the Canadian regional ice charts, the NASA Team algorithm underestimates the total ice-covered area by 20.4% to 33.5% during ice melt in the summer and by 7.6% to 43.5% during ice growth in the late fall.”
From: The Use of Operational Ice Charts for Evaluating Passive Microwave Ice Concentration Data, Agnew and Howell
http://www.tandfonline.com/doi/pdf/10.3137/ao.410405
John@EF,
First, you show me verified global harm that has resulted from the rise in CO2. Otherwise, you worry about something with no scientific evidence. You might as well worry about witch doctors. Me, I’ll worry about things that matter.
The historical climate indicates that CO2 sensitivity is either 1.5C per doubling or CO2 is not related to the temperature at all. I have all the numbers.
Is there any way mw can tell surface water from open water?
Smokey says:
August 29, 2012 at 2:22 pm
John Finn says:
“You don’t seem to understand the processes by which rising temperatures cause increases in CO2.”
That is what I have been trying to tell you. Rising temps cause CO2 to rise. But there is no measurable evidence of the reverse.
You appear to be trying to “move the goalposts”. I was disputing your claim that the increase in atmospheric CO2 over the past 100 years or so was the result of warmer temperatures. I am saying that you are not correct on this and that the main cause of increased CO2 concentrations is due to fossil fuel burning.
At no point have I stated about how much warming might result from increased CO2. However, like a number of responsible “sceptical” scientists (e.g. Lindzen, Jack Barrett etc), I do believe that an increased atmospheric CO2 concentration – particularly in the higher, colder, drier regions of the troposphere – must invariably produce some (possibly modest) warming. In the absence of any feedbacks the earth is likely to be about 1 deg warmer than it would otherwise be following a doubling of CO2.
Arctic ice extent for August 29 from NIC:
2007. 5.04 M sq miles
2012. 5.93 M sq miles
Phil. says:
August 29, 2012 at 1:10 pm
Phil. says:
August 29, 2012 at 12:21 pm
Phil. says:
August 29, 2012 at 11:17 am
In fact the evidence is that the last time that the that CO2 levels were this high was 15 million years ago. At that time the geography of Earth was different: no Panama canal and hence much different ocean circulation patterns.
Should be ‘Panama Isthmus’ of course.
Did you read the correction to the typo?
In case you made the same typo and really meant ‘Panama Isthmus’ try reading the following:
http://www.whoi.edu/oceanus/viewArticle.do?id=2508
http://www.nature.com/nature/journal/v393/n6686/abs/393673a0.html
kbmod I take it you’ve now had a chance to look at those references and
Louise says:
August 29, 2012 at 12:45 pm
and therefore will withdraw your remark.
Thank you.
[consider it withdrawn . . kbmod]
Records are fun, but it’s the trend that matters.
If I had to pick a turning point it would be when WUWT predicted 4.9 for ice extent this year. So much for Anthony’s “sea ice is recovering” theory. That was the “horse meet water” moment. I’m unsurprised he refuses to drink.
REPLY: Your statement works both ways, one of the most interesting aspects of this years storm induced breakup is that it allows for open surface water that normally would not be exposed to release LWIR into space. Lets see what happens in the refreeze. Also, look up 1922. – Anthony
Masie is at 4.1M km^2 as of yesterday 8/29.
http://nsidc.org/data/masie/
Here’s the page that Ron C is coming from. Select your month and year and submit.
http://www.natice.noaa.gov/products/ice_extent_graphs/arctic_daily_ice_extent.html
Yeah, that big storm and consequent smaller ones over the same area sure did a number on the ice. A quick rebound (refreeze)in extent would not surprise me one bit in the Chukchi Sea and East Siberian Sea with the ice(albeit low concentrations) still floating around.
“Let’s see what happens in the refreeze.”
Anthony:1 Reality:0
Nicely done. Your efforts have successfully contributed to the delay of any action on C02 emissions. I fully expect you’ll still be saying “let’s wait and see” even after the Arctic goes ice free.
The fossil fuel industry owes you a royalty cheque.
Does the low ice area cover have anything to do with the wind patterns associated with the unusual jetstream path this summer which has brought the UK the wettest summer since 1912?
From Jeff P. on August 30, 2012 at 10:17 am:
Royalty check? Are you saying Anthony Watts is a paid writer under contract to “the fossil fuel industry”?
Also, look up 1922. – Anthony
Do you mean this?
http://query.nytimes.com/mem/archive-free/pdf?res=950DE2DE1331EF33A25756C2A96F9C946395D6CF
It’s interesting that sea ice loss automatically gets blamed on warming, even though DMI shows no warming in the polar summer over the past 50 years. It actually shows a modest cooling. But the loss of sea ice will open up a lot of dark surface to absorb heat and re-radiate during the polar winter. Almost like a pan-arctic heat island effect! The ice loss is causing the observed arctic warming, not the other way around! The ice loss is probably due to soot emissions from China, because it started spiraling down right during the Chinese industrial revolution. Before that ice cover is thought to have been fairly steady.
It’s this heat island effect that’s causing the arctic warm to more than the rest of the globe. For all of its many adjustments, GISS and NCDC have never adjusted for the effects of lost ice on the temperature to more adequately determine how much of the warming can be ascribed to CO2!
Phil.,
The fact that CO2 allegedly haven’t been this high in 500,000 years is immaterial to the debate. The debate revolves around whether CO2 causes CAGWism, and there’s no evidence it does. The earth has been Co2 starved for the past 500,000 years. More CO2 is generally better for life. See co2science.org.
Hi Anthony,
What has happened to the links to the HYCOM graphics (Arctic SST, Extent, Thickness etc.)? Nothing is showing up in the Sea Ice Page and the graphics cannot be accessed using the posted links.
Greg Beasley
Greg Beasley, I gather that data is now pay-walled. The Defence Department that funded it thinks it can persuade us to pay for it…
Scratch that, it has reappeared!
It has been missing for a couple of weeks and there had been rumours on the web that it was now paywalled. No explanation as to why it disappeared and / or why it is now back.
Jim P. says:
August 30, 2012 at 2:15 pm
Phil.,
The fact that CO2 allegedly haven’t been this high in 500,000 years is immaterial to the debate. The debate revolves around whether CO2 causes CAGWism, and there’s no evidence it does. The earth has been Co2 starved for the past 500,000 years. More CO2 is generally better for life. See co2science.org.
No, this debate with Smokey revolves around Smokey’s erroneous assertions that Arctic seaice has been as low or lower than now regularly in the recent past, and he has specifically stated that “CO2 levels are about as low as they have ever been”, which I rebutted.
Pay no attention to Phil. He cannot even understand the chart I posted.
Sure, harmless, beneficial CO2 has risen from its absolute lows. But it is still right at the bottom of its geologic range. And since CO2 levels up to twenty times higher caused no global harm, the only rational response to the recent, relatively minuscule rise [the green line] is that CO2 has not caused any global harm, either.
If it has, post your evidence per the scientific method, showing global harm due to CO2. Make sure it is directly connected to human emissions, and show exactly why and how. Otherwise, the 31,400+ co-signers of the OISM Petition are correct when they state unequivocally that CO2 is harmless and beneficial. Who should we believe, thirty thousand scientists, including more than 9,000 PhD’s, all in the hard sciences? Or… Phil?
The best part is when you discount the satellite record as being too short a time period (only 33 years.. though for UAH, or RSS sat temps that’s OK)… and in the same post wax on about how MASIE and IMS, which have been up for last than 10 years… shows different numbers.
Funny.
Meanwhile, NSIDC is not the only place to go for long-term ice data… they’re simply the latest to show a record because of how they average out the days. Others have seen this coming for over a week.
http://neven1.typepad.com/blog/records/
9 records have been broken so far this year (in order of record broken):
Uni Bremen
Arctic ROOS Area
Cryosphere Today
Danish Met Inst.
Arctic Basin area (also put out by Cryosphere Today)
IJIS (Japan)
Arctic ROOS Extent
NSIDC
and today
PIOMAS – Volume
…….
http://neven1.typepad.com/.a/6a0133f03a1e37970b0177446fc134970d-pi
…….
Face it fellows, the Arctic is a shadow, quite literally, of it’s former self.
When it walks like a duck, talks like a duck, flies like a duck, quacks like a duck, waddlies like a duck, swims like a duck, dives like a duck, fishes like a duck, and paddles like a duck. It’s a duck!
Smokey says:
August 31, 2012 at 2:49 pm
Pay no attention to Phil. He cannot even understand the chart I posted.
Unfortunately it’s Smokey who doesn’t understand it!
“CO2 levels up to twenty times higher caused no global harm” he says, of course that was when there was no life on land. Considering that the rain would have the pH of vinegar not too surprising. Only 15% O2 in the atmosphere not too healthy either!
Once land plants developed the CO2 levels dropped to near contemporary values, we had the development of land animals, coincidence? (Late Devonian extinction)
The jump in CO2 after that corresponds with the Permian-Triassic extinction event. Shortly thereafter there’s another jump in CO2 and another extinction event, the Triassic-Jurassic.
A few years back Steve Goddard at The Register learned about the dangers of trying to interpret NSIDC charts without a full understanding of them. The Editor at The Register, and Steve Goddard, added retractions to that web page, stating that NSIDC got it wrong and that Goddard’s alternate interpretation was off the mark.
http://scienceblogs.com/islandofdoubt/2008/08/26/how-to-admit-youre-wrong/
In any case, why wast a lot of time on charts when you can see the melt down for yourself?
Watch this from space, there is more open water to come this year:
http://lance-modis.eosdis.nasa.gov/imagery/subsets/?project=aeronet&subset=Resolute_Bay.2012241.terra.2km
[Snip. Per site Policy, no Hitler references. ~dbs, mod.]
From Phil. on August 31, 2012 at 3:42 pm:
Water normally combines with carbon dioxide from the air to form a weak carbonic acid solution. Atmospheric CO₂ concentrations of 350ppm would yield a 5.6pH solution from distilled water left exposed to air.
At 25 times a 400ppm concentration, the pH would be 4.9.
Common distilled vinegar, aka white vinegar, runs about 2.4pH. With the logarithimic nature of the pH scale, that’s around 320 times the acidity from a CO₂ atmospheric concentration more that 25 times current.
Comparing the graph from Smokey with the timeline of life on Earth, land animals were present with CO₂ levels about five times contemporary values, far in excess of the IPCC’s absolute worst case scenario by 2100. Indeed, after lowering to current levels for between around 330 to 270 million years ago, CO₂ levels then significantly rose, only lowering to “worst case” about 50 million years ago, and to about current levels around 35 million years ago when grasses evolved and grasslands expanded.
Yet despite the CO₂ levels being so far in excess of current amounts, even in excess of “worst case” from around 260 to 50 million years ago, life went on. Go figure.
Thank you for providing this display of your scientific knowledge, it was quite enlightening.