Thanks for the link! The portal has been greatly improved. The date convention is parochial and ambiguous and needs to be fixed, as does the pole-hole clutter; the projection is compatible with Hycom, WorldView and PolarView though the orientation is off by -45º; palette errors are minor; single time-stamped tracks appear to be requestable, a proper variety of file formats are available for download, and volume swath integrals are provided.
But merging orbital thickness tracks over 27 days? It would seem to compare early orbits with later, possibly 'adjacent' orbits by which the ice has thickened, seen as radial streaks in Cryosat below. And we've seen ice move so much in a single day that everything would be thrown out of register a few orbits later.
Is there a practical way to correct for that motion? Yes, use the same scheme as UWisc did to advect TPW, it's open source and daily motion vectors are at NSIDC. That could yield thickness time series for individual parcels.
Meanwhile, a comparison is needed of the 10 Dec 15 to 06 Jan 17 Cryosat merger to the same 28 dates for daily Hycom ice thickness (being careful that none of the dates used there are forecasts, eg by unoptimizing the last 365 day product served on Jan 9th and deleting down to the date range).
Note first because Hycom, Cryosat and commonsensical cold-pole FDD independently agree along the CAA, it follows that Piomas is very wrong about December and appears not worth pursuing in this context.
However Piomas too provides a daily whole Arctic map series over this same time interval whereas Cryosat (like all narrow swath near-polar satellites) has a data pole-hole. So it may be worth looking at where and why Piomas is going wrong and perhaps how to correct and use it.
Neither CPOM nor Hycom are in standard 'Greenland down' position, differing by ±45º. Both have palette errors, meaning you cannot pull up all the ice of a given thickness range; the Cryosat is not bad whereas Hycom remains deep in the digital cartographic past. Since neither color scheme was worth preserving, both are re-oriented below into Nasa/NSIDC position with a 206.20% scale increase for Hycom.
To facilitate comparison, ideally both would be assigned the same thickness color scheme. That hasn't been feasible since neither uses a rational palette scheme; below Cryosat is held constant over the date range, as colored and as inverted, while Hycom is run through each date in turn.
The second animation shows a differencing scheme of thickness comparison (to Jan 6th Hycom only) that is not entirely satisfactory either.
The third shows SMOS ice thinness of Jan 6th compared to Hycom of the same date and Cryosat over the 28 day range ending on the 6th. There's fair agreement but inconsistency all around.
There's a trick for exiting palette silos, so the question is what makes for the best hybrid thickness model, eg SMOS on thin, Cryosat elsewhere, as modified by morphing ice. However even if were spot-on accurate and Arctic ice volume crashing, it's not clear who is listening. P Wadhams has said it all already and very well:
http://e360.yale.edu/feature/as_arctic_ocean_ice_disappears_global_climate_impacts_intensify_wadhams/3037/