Nick Stokes and Marcott Reconstruction

Nick Stokes has been discussing the Marcott et al 2013 Holocene temperature reconstruction over at Lucia's.  The climate outcasts tend to think that Marcott's method sucks while Nick thought it sucked less.  So after a lot of back and forth, Nick used his surface temperature program, TempLS with minor modifications to average the Paleo reconstructions. 

I stole a screen shot from his blogto show how things are working out.  This looks a lot more reasonable to me as far as the procedure goes.  The uncertainty though doesn't include the uncertainty of the individual proxies which is pretty significant and not necessarily linear and this also include 100 years smoothing on proxies that have natural smoothing of often more than 100 years.  It is a step in the right direction IMO.

One of the problems with irregular smoothing being resmoothed can be seen in this splice of the Tierney et al Lake Tanganyika lake surface temperature.

Since there very little over lap, I used the last point of the longer reconstruction with two of the shorter reconstruction at about 637 AD to create the anomalies.  As you can see there is a lot more variability in the higher resolution 1500 year reconstruction that the 60 ka reconstruction.  I would think that the shorter reconstruction variance whould be used for both series with happens to be about the error range Tierney mentioned in the original 2008 60,000 year reconstruction.  That error range should be used no matter what type of smoothing is done.

This chart used the Yamal tree ring temperature reconstruct by Hantemirov and Shiyatov to show what different smoothing periods do to the information.  With 125 year smoothing the spikes are not only subdued but inverted.  So a 60 year excursion would appear unprecedented in any reconstruction smoothed naturally or in processing.  Since there is evidence that climate has 60 year Pseudo-cycles, it is understandable that 100 year smoothing would eliminate that evidence.  So the uncertainty range should include that possibility.

My two cents.