Foreword: I had originally planned to post a story on this, but Steven Goddard of the UK Register sends word that he has already done a comparison. It mirrors much of what I would have written. There is a clear discrepancy between the two data sources. What is unclear is the cause. Is it differing measurement and tabulation methods? Or, is it some post measurement adjustment being applied. With a 30 percent difference, it would seem that the public would have difficulty determining which dataset is the truly representative one.
UPDATE: The questions have been answered, see correction below – Anthony
Arctic ice refuses to melt as ordered
Published Friday 15th August 2008 10:02 GMT – source story is here
Just a few weeks ago, predictions of Arctic ice collapse were buzzing all over the internet. Some scientists were predicting that the “North Pole may be ice-free for first time this summer”. Others predicted that the entire “polar ice cap would disappear this summer”.
The Arctic melt season is nearly done for this year. The sun is now very low above the horizon and will set for the winter at the North Pole in five weeks. And none of these dire predictions have come to pass. Yet there is, however, something odd going on with the ice data.
The National Snow and Ice Data Center (NSIDC) in Boulder, Colorado released an alarming graph on August 11, showing that Arctic ice was rapidly disappearing, back towards last year’s record minimum. Their data shows Arctic sea ice extent only 10 per cent greater than this date in 2007, and the second lowest on record. Here’s a smaller version of the graph:
The National Snow and Ice Data Center (NSIDC)’s troublesome ice graphThe problem is that this graph does not appear to be correct. Other data sources show Arctic ice having made a nice recovery this summer. NASA Marshall Space Flight Center data shows 2008 ice nearly identical to 2002, 2005 and 2006. Maps of Arctic ice extent are readily available from several sources, including the University of Illinois, which keeps a daily archive for the last 30 years. A comparison of these maps (derived from NSIDC data) below shows that Arctic ice extent was 30 per cent greater on August 11, 2008 than it was on the August 12, 2007. (2008 is a leap year, so the dates are offset by one.)
Ice at the Arctic: 2007 and 2008 snapshotsThe video below highlights the differences between those two dates. As you can see, ice has grown in nearly every direction since last summer – with a large increase in the area north of Siberia. Also note that the area around the Northwest Passage (west of Greenland) has seen a significant increase in ice. Some of the islands in the Canadian Archipelago are surrounded by more ice than they were during the summer of 1980.
The 30 per cent increase was calculated by counting pixels which contain colors representing ice. This is a conservative calculation, because of the map projection used. As the ice expands away from the pole, each new pixel represents a larger area – so the net effect is that the calculated 30 per cent increase is actually on the low side.
So how did NSIDC calculate a 10 per cent increase over 2007? Their graph appears to disagree with the maps by a factor of three (10 per cent vs. 30 per cent) – hardly a trivial discrepancy.
What melts the Arctic?
The Arctic did not experience the meltdowns forecast by NSIDC and the Norwegian Polar Year Secretariat. It didn’t even come close. Additionally, some current graphs and press releases from NSIDC seem less than conservative. There appears to be a consistent pattern of overstatement related to Arctic ice loss.
We know that Arctic summer ice extent is largely determined by variable oceanic and atmospheric currents such as the Arctic Oscillation. NASA claimed last summer that “not all the large changes seen in Arctic climate in recent years are a result of long-term trends associated with global warming”. The media tendency to knee-jerkingly blame everything on “global warming” makes for an easy story – but it is not based on solid science. ®
Bootnote
And what of the Antarctic? Down south, ice extent is well ahead of the recent average. Why isn’t NSIDC making similarly high-profile press releases about the increase in Antarctic ice over the last 30 years?
The author, Steven Goddard, is not affiliated directly or indirectly with any energy industry, nor does he have any current affiliation with any university.
NOTE OF CORRECTION FROM STEVEN GODDARD:
The senior editor at the Register has added a footnote to the article with
excerpts from Dr. Meier’s letter, and a short explanation of why my analysis
was incorrect.
To expound further – after a lot of examination of UIUC maps, I discovered
that while their 2008 maps appear golden, their 2007 maps do not agree well
with either NSIDC maps or NASA satellite imagery. NSIDC does not archive
their maps, but I found one map from August 19, 2007. I overlaid the NSIDC
map on top of the UIUC map from the same date. As you can see below, the
NSIDC ice map (white) shows considerably greater extent than the UIUC maps
(colors.) The UIUC ice sits back much further from the Canadian coast than
does the NSIDC ice. The land lines up perfectly between the maps, so it
appears possible that the UIUC ice is mapped using a different projection
than their land projection.
Click for larger image
Because the 2007 UIUC maps show less area, the increase in 2008 appears
greater. This is the crux of the problem. I am convinced that the NSIDC
data is correct and that my analysis is flawed. The technique is
theoretically correct, but the output is never better than the raw data.
Prior to writing the article, I had done quite a bit of comparison of UIUC
vs. NSIDC vs. NASA for this year. The hole in my methodology was not
performing the same analysis for last year. (The fact that NSIDC doesn’t
archive their maps of course contributed to the difficulty of that
exercise.)
My apologies to Dr. Meiers and Dr. Serreze, and NSIDC. Their analysis,
graphs and conclusions were all absolutely correct. Arctic ice is indeed
melting nearly as fast as last year, and this is indeed troubling.
– Steven Goddard
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But I have to break my promise already, since I realise I haven’t yet commented on the ‘leap year trick’.
1)Goddard’s premise is that the graph shows 10% greater for the same date. This is false, as I have demonstrated: it is actually 13.5% greater.
2) He then compares this with the ‘map’ renditions which he offsets on the grounds that it’s a leap year. Er, hang on a minute, wasn’t it a leap year when you were looking at the graph???????
3) So, he already i)has a false premise and ii)is not comparing the same days, the difference being in favour of the discrepancy he wants to display!
Frankly, how gullible does one have to be to be classed as a true ‘sceptic’?
All the impotent handwaving by the climate deceivers disregards these facts:
click1
click2
click3
click4
click5
click6
click7
Mr. Goddard has fully answered his critics. In globaloney parlance, his analysis is “robust.” The links above support Goddard’s article.
Want more? I got ’em. Just ask.
Steven,
Are you sure both Cryosphere maps and NSIDC charts use the same data?
Here’s the closest I could come to data sources
http://nsidc.org/data/collections.html
http://arctic.atmos.uiuc.edu/SEAICE/arctic.historical.seaice.doc.txt
Looks like several satellites and other methods are available.
Jeff C.
“And I would add The South pole sea ice trend is toward a larger sea ice extent/area. Why isn’t that what’s really important?”
If there is a real trend, it is very small in terms of a percentage of the sea ice amount. And it certainly is not due to cooling over the oceans surrounding Antarctica; in fact, the atmosphere appears to have warmed over the oceans surrounding Antarctica in the past few decades. Perhaps the warmer air, which can hold more water vapor, is leading to an increase in the snowfall which in turn is leading to an increase in sea ice.
I’m enjoying the irony that GW skeptics have been claiming that the small sea ice extent in 2007 had more to due with an unusual wind regime in the Arctic than with atmospheric warming and now they’re claiming that the greater amount of sea ice in 2008 vs. 2007 proves that the atmosphere isn’t warming.
Jeff,
An increase in snowfall can increase the thickness of sea ice, but it can’t increase the area. of the ice. If snow falls on open water, it melts immediately.
The only thing which can increase sea ice area is cold temperatures.
Jeff — “I’m enjoying the irony that GW skeptics have been claiming that the small sea ice extent in 2007 had more to due with an unusual wind regime in the Arctic than with atmospheric warming and now they’re claiming that the greater amount of sea ice in 2008 vs. 2007 proves that the atmosphere isn’t warming.”
Say, have a nice steaming cup of strawman with that enjoyment — on me!
What people here are responding to is the contention that 2008 was going to OBVIOUSLY be worse than 2007 because all of that 2008 ice was just “first year ice” and not the reliable crusty thick multi-year stuff.
The fact that 2008’s extent isn’t significantly BELOW the 2007 number because of the aforementioned claimed problem of lacking multi-year ice is simply remarkable. So much for the predictions of a worse year. The AGW alarmist’s 2008 predictions weren’t merely just wrong, they were in a class of abysmal prognostication skill that ranks up there with psychics. Witch doctors with chicken guts or orangutans with darts could have fared better.
Oh, and it wasn’t the skeptics claiming things about wind and current. They got that from this outfit called NASA. You may have heard of them.
I disagree with Patrick Henry.
Another factor that can increase sea ice area is the relative calmness of the sea and of the air above. Ice can be broken up mechanically. Keeping temperatures unchanged, stronger weather systems can result in larger areas of open water.
Actually, one wonders if the decrease in sea-ice area is anthropogenic indeed, but due to the combined action of hundreds of cruise vessels freed up by the collapse of the Soviet Union. In Antarctica, in fact, the decrease in sea-ice is strictly limited to the Pensinsula, where too a number of cruises is organized to travel to 😎
Here is an update from the Canadian Weather Service showing new ice rapidly forming in the Northwest Passage.
http://awberrimilla.blogspot.com/2008/08/yesterdays-new-ice.html
The Australian sailors attempting to navigate it are having a very difficult time with the ice , snow and cold, and are stuck in a snowstorm with strong northerly winds. Hopefully they won’t become the next victims of Arctic warming media hype.
Jeff,
Your logic is again flawed. NSIDC predicted that Arctic Ice extent would >12% lower than last year. Even using their highly questionable measurements, they are off by at least 25%. The point of the article is that the experts were wrong. The North Pole did not melt and the Arctic is not ice free.
Steve Talbot,
As far as the 10% vs. 13% goes, it sounds like you are making the argument that the NSIDC graph does not accurately represent their published data, showing less ice than there actually is. Regardless, it is irrelevant as the maps now (August 16) show 40% greater ice extent than 2007. The point is that there is a large disconnect between the maps and the graph. I don’t see any significant difference between the NSIDC maps and the UIUC maps, so the mystery remains unsolved.
All of the expert predictions of Arctic ice collapse in 2008 were dead wrong. The NSIDC maps and the NASA satellite images clearly show that there is a lot more ice than last year. If people can’t see that, then it must be because they don’t want to.
Glenn,
“Are you sure both Cryosphere maps and NSIDC charts use the same data?”
Well, according to Steven Goddard Cryosphere uses NSIDC data. He wrote in the article:
“A comparison of these maps (derived from NSIDC data) below shows…
Is this just another mistake that needs correcting?
Eyeballing the 8/15/08 daily maps from Cryosphere and NSDIC suggests very similar representation of coverage, although the resolution’s lower on the NSDIC map –
http://arctic.atmos.uiuc.edu/cryosphere/NEWIMAGES/arctic.seaice.some.000.png
http://nsidc.org/data/seaice_index/images/daily_images/N_daily_concentration_hires.png
Some more work there for the pixel counters!;-)
It’s interesting to compare the Cryosphere hi-res image above with the Cryosphere side by side comparison screen for August 15th
http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh?fm=08&fd=15&fy=2007&sm=08&sd=15&sy=2008
That looks kinda different to me. One test of the pixel-counting methodology would be to compare these two images for the same day from the same site. Not something I can be bothered to do, since I am not in pursuit of a conspiracy theory, but I have a hunch that some pixels would get counted as ice cover from the smaller image but not from the larger. But this is all silly stuff really, when the article’s premise has a 35% error anyway ( I note that when it comes to a piece like this another poster considers such an error margin to be “robust”!).
Steven Goddard
“Phil and Steven Talbot,
If the UIUC maps are correct, there is nothing in my extremely straightforward calculations which could be broken. You seem to be (rather obtusely) attempting to make an argument that the UIUC maps do not correctly map the satellite data on to the polar projection they use. Polar map projections have minimum distortion at the pole, where the land is perpendicular to the viewer.”
No you ‘rather obtusely’ continue to deny the facts regarding the maps being used, I shouldn’t have to tell you three times, your assumption regarding the projection used is incorrect! See below for detail on the projection used.
If you wish to argue that the UIUC maps are incorrect, that might be an interesting topic of discussion. However, you have yet to make any attempt to analyze the methodology I used – which (obviously) assumes the correctness of the maps.
The maps are correct, they just aren’t what you assume them to be.
According to the UIUC maps, there has been almost no change in the amount of Arctic ice since August 8. Once again, if you believe those maps are incorrect – please state your case – and I suggest that you take it up with Phil Chapman over at CT.
Just about 2%/day!
As you can see below NSIDC are performing much more accurate calculations than your pixel counting on the low resolution graphic at CT (as mentioned elsewhere in the thread why didn’t you use the high res graphic?).
“The polar stereographic projection specifies a projection plane or grid secant to the Earth at 70 degrees. The planar grid is designed so that the grid cells at 70 degrees latitude are 25 km by 25 km. For more information on this topic please refer to Pearson (1990) and Snyder (1987). This projection often assumes that the plane is tangent to the Earth at the pole. Thus, since there is a one-to-one mapping between the Earth’s surface and the grid at the pole, there is no distortion at the pole. Distortion in the grid increases as the latitude decreases, because more of the Earth’s surface falls into any given grid cell, which can be quite significant at the edge of the northern SSM/I grid where distortion reaches 31 percent. For the southern grid, the SSM/I grid has a maximum distortion of 22 percent. To minimize the distortion, the projection is true at 70 degrees rather than at the poles. This increases the distortion at the poles by three percent and decreases the distortion at the grid boundaries by the same amount. The latitude of 70 degrees was selected so that little or no distortion would occur in the marginal ice zone. Another result of this assumption is that fewer grid cells will be required, as the Earth’s surface is more accurately represented. This saves about 100 megabytes per year in data storage.
The polar stereographic formulae for converting between latitude/longitude and x-y grid coordinates have been taken from map projections used by the U.S. Geological Survey (Snyder 1982). Several different ellipsoids were compared to the Hughes ellipsoid and in each case, differences were less than 1 km over the SSM/I grids. However, differences of up to 9 km were found if a sphere rather than an ellipsoid was used. Thus, it is an explicit requirement that an ellipsoid be used in processing the data.
An ellipsoid is defined by equatorial radius and eccentricity. The ellipsoid used in the Hughes software assumes a radius of 3443.992 nautical miles or 6378.273 kilometers (km) and an eccentricity (e) of 0.081816153. To properly convert these coordinates to a polar stereographic grid (the projection of choice), the conversion should assume the Hughes ellipsoid.”
Steve Goddard:
“Your logic is again flawed. NSIDC predicted that Arctic Ice extent would >12% lower than last year”
Care to say where they said this? I’ve been unable to find it, however I did find the following.
NSIDC comment from April:
“Despite strong growth of new ice over the winter, sea ice is still in a general state of decline. The ice that grew over the past winter is relatively thin, first-year ice that is susceptible to melting away during the summer. Although natural variability in the atmospheric circulation could prevent the ice pack from breaking last year’s summer record, a closer look at sea ice conditions indicates that the September 2008 minimum extent will almost certainly be well below average.”
Although you claim the the above, I could not find the link anywhere on climateaudit.org that led to the above. Could you provide a definitive URL on CA that leads to the above?
Thanks!
Jack Koenig, Editor
The Mysterious Climate Project
http://www.climateclinic.com
Here you go: http://www.climateaudit.org/?p=3336#comment-289313
Steve Goddard wrote
“Your logic is again flawed. NSIDC predicted that Arctic Ice extent would >12% lower than last year. Even using their highly questionable measurements, they are off by at least 25%. The point of the article is that the experts were wrong. The North Pole did not melt and the Arctic is not ice free.”
A pathetic attempt to divert attention from the issue. Steve Goddard claimed that NSIDC’s was claiming that the sea ice EXTENT was 10 percent greater when in fact it actually was 30 percent. I showed that the actual difference in AREA was 13 percent (I incorrectly stated 14 percent yesterday), not the 30 percent that Mr. Goddard mysteriously came up with, meaning that NSIDC’s claim of an approximately 10 percent difference in EXTENT is highly plausible. Now he trying to obscure the issue by bringing up an alleged forecast of a 12 percent decrease that he claims that someone made and stating that there was a 25 percent error in the “forecast.”
Mr. Goddard now is claiming that the measurements are “questionable”. The algorithm has been published, so I’m interested in Mr. Goddard’s take on what is wrong with it.
And of course he repeats the lie that the “experts” forecast that the North Pole would be ice free this summer. He then invents a whole new lie that there was a forecast that the arctic would be ice free. What will he claim next?
Patrick Henry
“The only thing which can increase sea ice area is cold temperatures.”
Wrong. Winds and currents play a role. If you can find a data set showing that temperatures around (as opposed to over the interior) of Antarctica are cooling, please post it. Every one that I’ve seen has shown warming.
Phil,
You keep describing the NSIDC map projection (ad nauseum,) which is not the one that CT uses in their maps and not the map set that I used. Rather, I used the CT maps which are higher resolution than the NSIDC maps, have more detail, and are archived every day. No matter how many times you describe the NSIDC projection, it doesn’t have any impact on this discussion.
As I have attempted to explain to you before, the CT projection is the view of an astronaut 10,000 miles over the North Pole. The only point which is undistorted is right at the pole. As you move away from the pole, the distortion increases approximately as the sine of the latitude. (At 30 degrees latitude, a pixel would represent 2X as much area as one at the pole.) Thus my calculations are conservative, because the actual amount of ice increase away from the pole is greater than the pixel count. This is not a question of pixel precision, which has very little impact on the 30% number.
NSIDC forecast in May that extent would break last year’s minimum record by about 13% at 3.59 Mkm2. See figure 4.
http://nsidc.org/arcticseaicenews/2008/050508.html
If you accept their current +14% number, that is a misprediction of 27%.
From the UIUC data you can add up all polar sea areas covered by ice: I get 3.3 million km2 for August 16, 2008. The IJIS value (15 % ice coverage and more) of 08/16 is 5.91 million km2, a change of 0.07 million km2 from 08/15. The NSIDC value is very similar. The corresponding numbers for 2007 are 0.7 to 0.8 million km2 lower, both for IJIJ, NSIDC and for UIUC (the latter is estimated ‘by visual inspection’).
In Germany, the low 2007 ice coverage was seen by the AGW protagonists as the tipping point, beyond which any skepticism was no longer allowed or should even be forbidden.
randomengineer, you only need to go back to the Oct. 2007 “issue” to see where our host was playing the 2007 record minimum was due to winds not warming card so the decrease in 2007 was not evidence of global warming. If the decrease from 2006 to 2007 was not proof of warming then why is the increase from 2007 to 2008 proof of global cooling?
Steven Talbot,
I’m keeping a running count of 2008 vs. 2007 from the full resolution (850×850) CT maps. August 15, 2008 shows 41% greater extent than August 16, 2007.
An interesting statistic is that according to CT, Arctic ice area bottomed out by August 17 last year – which means that ongoing losses in extent after that date were probably due to compaction, rather than melting.
Steven Talbot said
“Glenn,
“Are you sure both Cryosphere maps and NSIDC charts use the same data?”
Well, according to Steven Goddard Cryosphere uses NSIDC data. He wrote in the article:
“A comparison of these maps (derived from NSIDC data) below shows…
Is this just another mistake that needs correcting?”
I’d say so. You didn’t answer the question, and it was you who insisted on the data originating from the same source. Not sure whether the above quote from Goddard is correctly interpreted as a claim that the Cryosphere
map is derived from NSIDC. It may be that he used assigned the map area found to the NSIDC numbers – his comparison used the NSIDC data, from the NSIDC chart.
Another mistake of yours is the attempt made (02:37:07) to confuse sea ice area with arctic ocean area with a minimum sea ice concentration. Both
the NSIDC graph and the Cryosphere maps depict ocean area, and is what Goddard has compared.
Another is your criticism of Goddard’s 10% figure, which is much closer than your 13.5%, upon analysis of the NSIDC graph itself that Goddard used.
I get a 2007 minimum for the dated graph of 5.7 mil, and the 2008 area as 6.3 mil. 10% of 5.7 added to 5.7 is 6.27, real close to being 6.3 mil. You used some quote from an NSIDC webpage to make your calcs. So you again used a different source to refute a claim based on a different source.
Yet another is the big deal you made of a leap day, and it isn’t a big deal at all. IMO it is quite fair and reasonable to compare “same day as last year” as 365 days ago, not 366 or 3 or 498.
It appears that Goddard has a point, whether the data source is the same or not. And I don’t need to count pixels, just use a pencil as a straightedge on the monitor looking at the Cryosphere maps. It is most obvious just eyeballing that quite a bit more area is covered than a half mil from the same time last year. And his 30% more probably isn’t far off if at all.
Steven Goddard
“You keep describing the NSIDC map projection (ad nauseum,) which is not the one that CT uses in their maps and not the map set that I used. Rather, I used the CT maps which are higher resolution than the NSIDC maps, have more detail, and are archived every day. No matter how many times you describe the NSIDC projection, it doesn’t have any impact on this discussion.”
The CT maps might contain more pixels than the NSIDC maps but that doesn’t change the fundamental resolution of the data. It just creates an image that is larger on a computer monitor.
“The CT maps might contain more pixels than the NSIDC maps but that doesn’t change the fundamental resolution of the data. It just creates an image that is larger on a computer monitor.”
You lost me there, Jeff. The number of pixels IS resolution. And i fail to understand how “larger on a monitor” is relevant. Your monitor bigger than mine, or what.
Glenn,
You didn’t answer the question, and it was you who insisted on the data originating from the same source.
As I have indicated, I was naive enough to accept that Goddard’s statement was accurate. This confused me until you made clear that it could not be. Yes, I was insisting the data was the same source, since that was what Goddard had stated. My argument was proceeding from his stated premises.
Not sure whether the above quote from Goddard is correctly interpreted as a claim that the Cryosphere map is derived from NSIDC.
Huh? The statement was “these maps (derived from NSIDC data)”. That seems a pretty clear process of interpretation to me, Glenn!
Another mistake of yours is the attempt made (02:37:07) to confuse sea ice area with arctic ocean area with a minimum sea ice concentration. Both
the NSIDC graph and the Cryosphere maps depict ocean area, and is what Goddard has compared.
Yes, I accept that, though it wasn’t an “attempt to confuse”, but a mistake. Please note that I accept when I have made a mistake, unlike some others.
Another is your criticism of Goddard’s 10% figure, which is much closer than your 13.5%, upon analysis of the NSIDC graph itself that Goddard used…..You used some quote from an NSIDC webpage to make your calcs. So you again used a different source to refute a claim based on a different source.
No, that is wrong – it is the same source, the 11th August press release, to which Goddard refers. The graph was not released independently but as part of that press release, which includes the actual figures (in preference to either your or Goddard’s eyeballing). It seems pretty obvious to me that the graph does not have the resolution to compute percentage differences accurately and that one should refer to the figures which were given.
Yet another is the big deal you made of a leap day, and it isn’t a big deal at all. IMO it is quite fair and reasonable to compare “same day as last year” as 365 days ago, not 366 or 3 or 498.
You seem to have missed my point entirely. That may be reasonable in itself, but Goddard only applied this principle in comparing maps. With the graph he compares the same calendar date. Therefore, the offset was in favour of showing a greater differential. (Please note that I have accepted a mistake above. This is a mistake, or a failure to understand the point, on your part).
It appears that Goddard has a point, whether the data source is the same or not. And I don’t need to count pixels, just use a pencil as a straightedge on the monitor looking at the Cryosphere maps. It is most obvious just eyeballing that quite a bit more area is covered than a half mil from the same time last year. And his 30% more probably isn’t far off if at all.
It’s certainly possible that there is a point to be made about how effective these maps are as a visual representation of sea ice extent. Not very, I think. But the map is not a data source but rather a representation of a data source (just as a graph is not a data source). Goddard stated “The problem is that this graph does not appear to be correct. Other data sources show Arctic ice having made a nice recovery this summer…”. Three points here: 1) there are no grounds to presume that the graph is “not correct” rather than that the maps are “not correct” and 2) the NISDC maps exhibit the same visual coverage as the Cryosphere ones, so the insinuation that “other sources” show the graph to be “not correct” is unsound and 3) Goddard ignores the actual data sources, which were available.
The article allows the inference that someone is “cooking the data” in a biased fashion. IMV, that was its intent. IMV also, that is unjustified.
I wonder how this will affect the Artic region in the near term. The sulphur cloud from Kasatochi is circling the Artic right now. And I have been hearing of cold air building a little early in the Artic, also.
2008-08-16 04:49:20
Volcanic unrest continues at Kasatochi volcano. Seismic activity is still being detected on the AVO seismic network located on Great Sitkin Island, 25 miles to the west.
AVO has received no new reports of activity or ash emissions. A sulfur dioxide cloud produced by the Aug. 7 eruption remains at high altitudes in the circum arctic region.
http://www.avo.alaska.edu/image.php?id=15049
Apparently this cloud is the one of the largest observed since 1991 Hudson eruption in Chile.
http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=18118
I understand this will have no long term effect because it didn’t get high enough, but it can create an aerosol haze that, in the short term, could reflect the little sunlight that is now entering the Artic region. And some mets are talking about an early build up of cold air. Models do seem to suggest this. Could we possibly see an early ice extent minimum this year? By about 2 weeks, maybe?
I guess it’s a wait and see.
I just found this site. Daily SO2 images from around the globe.
http://satepsanone.nesdis.noaa.gov/pub/OMI/OMISO2/index.html