Thanks for the answer, it’s always helps to know where to look for this information. As a layman, that’s not always the easiest thing to do.

You’d figure that they will run into problems when (if) the data actually does begin changing: due to either rising or falling temperatures. Good to see that the program is actually being fixed.

“’ve been looking at the AMSRE_Sea_Ice_Extent graph and noticed at about the beginning of June there is an increase in sea ice extent most years. It just curiosity really but what is the phenomenon which causes that?”

This was well answered a couple of months back by the Japanese agency. On June 1, they switch to a different algorithm for to account for the development of melt water on the ice surface so as not to be calculated as open sea water.

Straight from the IARC-JAXA site:

“The current version of data processing produces an erroneous blip of sea-ice extent on June 1 and October 15, which is seen in the graph of sea-ice extent as a small peak on these dates. The apparent blip arises due to switching of some parameters in the processing on those dates. The parameter switching is needed because the surface of the Arctic sea ice becomes wet in summer due to the melting of ice, drastically changing the satellite-observed signatures of sea ice. We will soon improve the processing to make the graph much smoother.”

This is a layman’s question.

I’ve been looking at the AMSRE_Sea_Ice_Extent graph and noticed at about the beginning of June there is an increase in sea ice extent most years. It just curiosity really but what is the phenomenon which causes that?

REPLY: no need, already known, but thanks. – Anthony

His recent befouling of Climate Progress is typical of his ‘big man on-line’ behaviour.

As soon as he appears in a comment thread I just hit the close button no matter how important the original post – it’s just not worth wading through his waist deep [excrement] to find reasonable and informed comments.

He thinks his trivial contributions play an important part in fighting the good fight for the ‘carbon is pollution’ crowd, but instead he devalues otherwise generally commendable blogs like Climate Progress and turns them into unreadable effluent.

The comparison between the tone here and the blogs to which he has seemingly unfettered access is remarkable and I’d like to thank Anthony and his moderators for keeping it so.

It was in ‘Spaceflight Now’, http://www.spaceflightnow.com/atlas/av017/081006delay.html

“The present-generation DMSP satellites were built with a four-year design life, yet most have been lasting eight years or more.

“We upgraded F15 and F16 with Single Gyro software to extend satellite life with improved attitude control. Further, both F15 and F16 were built with solid state recorders which replaced the old analog recorders that were life-limiting items on prior DMSP satellites,” program officials said.”

Glenn (17:26:54) :
Phil. (16:26:22) :

Not a minor nitpick, these are not images, but maps generated from algorythms.

Actually they are images, just like MRIs are images and PET scans produce images.

Nope, can’t see a problem here. Use a failing sensor to cal a new one.

“Note the close correspondence between the two data records.”

Nothing up my sleeve…Presto! They match.
Give me a break. They need to switch to a SAR sensor.

“This is a high resolution image from the AMSR-E satellite”

Not a minor nitpick, these are not images, but maps generated from algorythms.

Nansen compares SSMI and AMSR:
http://arctic-roos.org/observations/satellite-data/sea-ice/Arctic-ice-concentration-maps-from-SSMI-and-AMSRE

Concerning archived data, Nansen and NSIDC both show about the same current extent, but vary significantly in the 2007 line. Nansen shows current 2007 (June 4-5) to be around 500K less than NSIDC:
http://nsidc.org/data/seaice_index/images/daily_images/N_timeseries.png
http://arctic-roos.org/observations/satellite-data/sea-ice/ice-area-and-extent-in-arctic

Dhogoza- we love you-trolly(sic) we do

This is a high resolution image from the AMSR-E satellite

from this http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/ARCHIVE/20090604.jpg

This is an image from the SSMI imager on board the F15 satellite (used in the archives to maintain consistency with the past images, unfortunately no longer gives usable images which is why CT doesn’t link to it.) It’s also why CT display the following message if you try to compare images (if you go the back door route you don’t see it):
“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.”

from this http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/ARCHIVE/20090604.jpg

I understand the satelite is messing up.. ignore the central ice mass, the edges are where the real difference hits, particularly in the “Barents sea”. It would seem that they are correcting the edges somehow? I suspect this is how intrepid explorers get the impression that open water exists where there is still ice.

Thanks to one of your readers for teaching me this trick… even if they dont show the image in their archive page, they still save a jpg of it to its date in the archive folder:) I guess im just not understanding why in the archive jpg, the ice is shown as solid, and in the main site page.. its water and thin ice.

Thanks for the info about F18.

As for Aqua, there are several instrument packages aboard the Aqua satellite: AMSR-E (Japan), HSB (Brazil), MODIS, AMSU-A, AIRS, and CERES (not sure if these last four are NASA/NOAA programs or not).

So NSIDC sticks with the DMSP satellite program – it’s no wonder, it’s a single agency (NOAA) program – one has to wonder about the future of Aqua. Will NASA keep the program in place? Will other nations continue to take part in it (such as Japan)? When politics (funding concerns, national interests, etc.) and science mix, a degree of uncertainty and compromise is involved. Plus, Aqua is just one of several satellites in the Earth Observing System (EOS) which also include Terra, Aura, CALIPSO, CloudSat, and PARASOL (France). Looks like science isn’t as simple as we’d like it to be.