You may recall that I posted about how the National Snow and Ice Data Center has an issue with the DMSP satellite sensor channel used to detect sea ice. Cryosphere Today is a few days behind in update compared to NSIDC, and here is what their imagery now looks like before and after:
Above: Arctic “Insta-melt” Click for a larger image
Here is the link to reproduce the image above.
Larger “holes” are likely to open up in the arctic sea in the next couple of days as the sensor further degrades.
Here is what CT has to say as a caveat for the side by side images:
February 17, 2009 – The SSMI sensor seems to be acting up and dropping data swaths from time to time in recent days. Missing swaths will appear on these images as a missing data in the southern latitudes. If this persists for more than a few weeks, we will start to fill in these missing data swaths with the ice concentration from the previous day. Note – these missing swaths do not affect the timeseries or any other plots on the Cryosphere Today as they are comprised of moving averages of at least three days.
No mention of the issue on CT’s main page though. They are still commenting on George Will. They seem a bit out of touch on the sensor issue.
h/t to Garrett
UPDATE: 11:30PM 2/20 CT has removed the comments about George Will from the main page, but still no mention there of the satellite outage nor are they displaying imagery on the main page from 2/20/09 The most recent is 02/19/09. It will be interesting to see what tomorrow brings.
Cryosphere has now removed the SSMI version for the northern hemisphere without comment. It is apparently still used for the southern hemisphere, also without comment.
For an alternate set of Snow & Ice charts see IMS Products http://www.natice.noaa.gov/ims/at the The National Ice Center’s website http://www.natice.noaa.gov/
Hi Philip. The two letters “at” at the end of the url make it not work. when I manually removed them it worked.
Hi Jack,
The “IMS Products” bit works OK and is the correct link. Because I did not put a space after the greater than symbol, the system tried to post the URL twice, confusing my next word “at” as part of the h t t p code. My bad.
A bit OT, but temperature at Summit on the Greenland Icecap hit -61 Centigrade this morning:
http://www.wunderground.com/history/station/04416/2009/2/22/DailyHistory.html?req_city=NA&req_state=NA&req_statename=NA
That is getting close to the all-time Greenland record of -65 from 1954. Temperatures have also been very low on the sea-ice north of Greenland in the last few weeks with unmanned stations regularily recording temperatures in the mid-forties below.
I hope that ice-thickness survey expedition has the sense to wait for the weather to moderate before setting out. Being outdoors when it’s in the forties below is very tough except in a dead calm.
Without daily updates of the arctic ice extent this is going to be a long, hot and very boring summer 😉
Hans
Just click on the JAXA graphic on the side of this page (two images above the Sun) that Anthony has so kindly placed for his readers, and you’ll get your dose!
Are we seeing the same mistake in the Antarctic data (http://nsidc.org/data/seaice_index/images/daily_images/S_timeseries.png) due to the sensor failure but for which the data has not yet been corrected? (If so does that mean that things don’t get corrected without a blog in spite of the comment by Walt Meier “I’m not sure why you think things like this are worth blogging about”?) Have we been so focused on the Arctic that we’ve not noticed the same error in the Antarctic? (I’m assuming it is the same error.) The Cryosphere Today Webpage shows no difference in the anomaly compared to the data for the 1979 to 2000 mean.
REPLY: I’ve asked Walt Meier the question. My take on it yes, the sensor issue is skewing that graph. But we’ll see what he says. CT has not been updating, it appears that they seem to think they can work around the problem. – Anthony
REPLY2: Walt Meier responded within half an hour. Yes it is wrong and due to sensor error. They’ll be taking it down tomorrow – Anthony
Sir Anthony [ The Rev]
I was a crazy thing: if a volcanic activity.
http://earthquake.usgs.gov/eqcenter/recenteqsww/Quakes/us2009dibg.php
The thread is getting toward its end.
However, others mentioned the discrepancies (between Day #1 and Day #2) in addition to the Rorschach butterfly. For fun, in Photoshop, I overlaid the two days and changed colors of one day’s layer so differences would “stand out”. If you can follow the convoluted legend and color coding the differences are rather outstanding. Click URL below for the layered image. As others have noted, there is a heck of a lot more than the mere butterfly (itself hundreds of km across) and one wonders just how accurate any of this has been for years. (The scale arrow is crude…)
http://photoshare.shaw.ca/image/2/d/8/63987/overlay24hours-0.jpg
Cheers!
Clive from the Frozen North ☺
Alberta, Canada
if you add day three, 21st , it will show more a lot of changes too.
http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh?fm=02&fd=20&fy=2009&sm=02&sd=21&sy=2009
day 4 is back to normal on first glance, but I do not know what your scheme would show. Probably the error is geographically over the snow part that is covered by different data.
It is, IMHO, unfair to lump CT with some of the really questionable climate science endeavors. They do not control the remote sensing technology and have been transparent about their methodology. If you don’t agree or don’t understand, they will respond to questions in my experience, and while they may have taken a position on AGW, I don’t find anything resembling RC’s contempt for agnostics or atheists.
CT in making comment about the George Will article, state that the decrease in sea ice area/extent in the Artic summer is consistent with predictions of Climate Models.
There must be a reasoning behind the model algorithms that give this result, so does anyone know what the mechanism is.
Intuitively I would have thought the trend in Winter Sea Ice area/extent is where we should look at if we want to see the effects of AGW, the Artic winter is free from the effects of direct solar, so only the AGW atmospheric gas warming should be left.
Interesting bit of related news. On this next shuttle flight the Orbital Carbon Observatory will be launched (who says we don’t spend enough on climate research). http://oco.jpl.nasa.gov/
If this backs up the limited surface studies that have shown that North America is a large Carbon sink, I wonder what that will do to policy intiatives and those that point to the US as the #1 emitter culprit.
The ice sensor issue finally hit the broadcast new tonight, it was mentioned on Special Report with Bret Baier on Fox tonight (2/23/09). It was a pretty straight forward report, the ususal 30 second item, that the sensor issue resulted in an underestimation of ice extent about equivalent to the size of the state of California and a statement by NSIDC that it did not change the conclusion that sea ice is shrinking.
I have not seen a web item on the sensor glitch on their site yet though.
It will be interesting it other broadcast outlets also pick this up.
Larry
NOAA’s SST site is having sensor issues as well. See:
http://www.osdpd.noaa.gov/PSB/EPS/SST/data/anomnight.2.23.2009.gif
http://en.wikipedia.org/wiki/Global_Historical_Climatology_Network
“The Global Historical Climatology Network (GHCN) is a database of temperature, precipitation and pressure records managed by the National Climatic Data Center”
“This work is often used as a foundation for reconstructing past global temperatures, such as NASA’s GISTEMP.”
Hansen apparently uses some satellite data for his “global temperature” maps. In light of this, I wonder whether there may be some problem with this one for example:
http://data.giss.nasa.gov/cgi-bin/gistemp/do_nmap.py?year_last=2009&month_last=01&sat=4&sst=0&type=anoms&mean_gen=01&year1=2009&year2=2009&base1=1951&base2=1980&radius=1200&pol=reg
I have a question, what sense does the following statement make?
[emphisis mine]
How can increased accuracy possibly degrade the overall consistency? This is not logic.
And here, folks, we bring you the latest on the new phase of water :”disappearing/reappearing ice” thanks to cryosphere.
Just the last two records:
http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh?fm=02&fd=22&fy=2009&sm=02&sd=23&sy=2009
Before you know it, the MSM will announce an ice-free arctic! Clearly the sea ice is melting in large swathes. ;-P
http://www.foxnews.com/story/0,2933,498967,00.html
Last paragraph…..
And finally, a glitch in satellite sensors has caused scientists to underestimate the extent of Arctic sea ice by 193,000 square miles. That’s a chunk of ice about the size of California. The National Snow and Ice Data Center says the error was due to a problem called “sensor drift” and lasted from early January to the middle of this month.
The extent of Arctic sea ice is seen as a key measure of how rising temperatures are affecting the planet. The center says on its Web site: “Although we believe that data prior to early January are reliable, we will conduct a full quality check.”
It maintains that the recent error does not change findings that Arctic ice is retreating.
What are the chances that 2 different ice sensors (I’m assuming dmsp and ssmi are from two different satellites) go on the fritz at the same time? I think it’s possible there is some monkey business going on in reporting actual ice area. Does Hansen have control of these two satellites?
I meant to have said “at around the same time”
the continuing saga has the butterfly almost back
http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh?fm=02&fd=23&fy=2009&sm=02&sd=24&sy=2009
How can one believe that
February 17, 2009 – The SSMI sensor seems to be acting up and dropping data swaths from time to time in recent days. Missing swaths will appear on these images as a missing data in the southern latitudes. If this persists for more than a few weeks, we will start to fill in these missing data swaths with the ice concentration from the previous day. Note – these missing swaths do not affect the timeseries or any other plots on the Cryosphere Today as they are comprised of moving averages of at least three days.
the moving averages are not affected? here we have more than three consecutive days with erratic appearance and disappearance of large chunks of ice.
Mark (13:46:52) :
“What are the chances that 2 different ice sensors (I’m assuming dmsp and ssmi are from two different satellites) go on the fritz at the same time? I think it’s possible there is some monkey business going on in reporting actual ice area. Does Hansen have control of these two satellites?”
DMSP is a defense satellite program, ssm/i is an instrument onboard a DOD satellite. This sensor is aboard several satellites, but the sensor error in the current limelight is from the one on the DMSP F15 satellite, which is, among others, NSIDC’s source of ice data.
Hansen as I understand it only analyzes data, and would not be in operational control of any satellite, although he is a senior NASA scientist it is unlikely he would have any say in the control of any satellites, but definitely not a DOD satellite.
Glenn (17:06:42) :
I was being sarcastic in my comment about Hansen because of how GISS adjusts its temperature data.
I just find it odd that two ice area satellites have issues at around the same. Parts of this winter have been exceptionally cold and I’m concerned that the actual ice area may be higher than what is being reported (due to the sensor issues).
Update, NSIDC graph current:
http://nsidc.org/data/seaice_index/images/daily_images/N_timeseries.png
No explanation as yet on
http://nsidc.org/arcticseaicenews/
Appears that minor changes were made on data as far back as Nov 2008, to around Jan 25 2009, when the change becomes more significant. compare:
http://wattsupwiththat.files.wordpress.com/2009/02/nsidc_extent_timeseries_021509.png
Seems the North Pole is truly ice free as of today, beating AGW predictions yet again:
http://iabp.apl.washington.edu/maps_daily_ncepice.html
and yesterday as well:
http://arctic.atmos.uiuc.edu/cryosphere/NEWIMAGES/arctic.seaice.some.000.png
Mark (06:39:33) :
“I just find it odd that two ice area satellites have issues at around the same.”
What two satellites? The sensor problem as I explained (and NSIDC has) is on the F15 satellite.
On another note, there have been many sensor problems on multiple satellites in the past (including the current one), and some remain errors that are attempted to be accounted for in both current and archived data.
Cryosphere’s image comparator no longer has 2009 images.
http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh says:
It looks like they’ve stopped updating http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/current.365.jpg and I assume most everything else.
Cryosphere has removed all of 2009 from the comparison maps.
February 25, 2009 – The SSMI images for many days in 2009 were bad enough that we removed them from this comparison display (see note below and the NSIDC website). There is enough interest in these side-by-side comparison images that we will try to replace them with corresponding images from the AMSR-E sensor in the coming weeks.
Glenn, you wrote this “DMSP is a defense satellite program, ssm/i is an instrument onboard a DOD satellite” which I took as meaning two satellites. However, I didn’t read the second part of your comment which I should have.
Cryosphere removed the maps of comparison where the error is glaringly obvious, but the front page map of the northern ice area still displays this new phase of water/ice since it shows less than 100% in the middle, and in the middle of the winter season.
http://arctic.atmos.uiuc.edu/cryosphere/