Among the ice charts I peek at every day is the one from DMI (Danish Meteorological Institute).
Today there was a new Sea Ice Extent Chart with this text at the bottom:
The plot above replaces an earlier sea ice extent plot, that was based on data with the coastal zones masked out.
That implied that the previous sea ice extent estimates were underestimated.
The new plot displays absolute sea ice extent estimates.
Arctic Sea Ice Extent supposedly bottomed out around 2.5 million sq km according to the old chart posted by DMI for months.
Imagine my surprise when today the Sea Ice Extent bottomed out at 4 million sq km. and the chart looked like
Maybe that explains why Arctic-roos site isn’t showing any charts.
sunshine hours 
What happened to that drop in ice in early august from that huge storm? It’s gone in the updated graph. Perhaps they want to erase the ice loss from that storm?
Good point. The Aug storm was well displayed in the old graph.
Maybe that is the point?
It looks as if this year’s ice extent and all the past years have been shifted up by about 2 m km2. How could such a shift be justified and the implied error over the years perpetuated?
“that was based on data with the coastal zones masked out”
Plausible. Their old algorithm was wrong and they are fixing it. However kramer (another commenter) makes a good point that the Aug storm disappeared. I am suspicious.
Arctic-roos / ssmi has gone dead too: http://arctic-roos.org/observations/satellite-data/sea-ice/observation_images/ssmi1_ice_ext.png
The storm jammed ice onto the coasts, which are now taken into account. So the drop wasn’t.
http://www.ijis.iarc.uaf.edu/en/home/seaice_extent.htm
This graph consistently showed the bottom at around 4.
Changing one’s metric *today* never justifies changing history. It is true that those who ignore history are doomed to repeat it. That is because we have much to learn from history that can help us avoid repeating it. But when we change our history for our own convenience, we lose the ability to learn from it.
Changing your own history is lying to yourself. It doomed the civilization of the Pharaohs.
I would rather own an ugly Timex watch that keeps good time, than the most beautiful gold and gem-encrusted Rolex that doesn’t run at all.
There is still something not explained in the shifts shown in the graphs — why should the average peak be around 16 mil sq km when the old graph show all those past years average peak at 14.
Sorry, the old peak was at 12 — damn short term memory.
Using 2012:
2.5 to 4 for the low = 1.5
11.5 to 15 or so for the high. = 3.5
Strange.