A technical snag which I'm still working on is that this model does not generate the info needed to adjust to a base period. It may be necessary to add that as another fitting parameter. However, since I'm currently comparing to GISS, I just add an offset to match the GISS average anomaly for the relevant year.
I've compared these with the GISS plots. I've also gone back to match the trands of the previous post with the GISS trends for the same period, since GISS produces better maps. BY request, I've also plotted the trend for the period 1900-1945 and compared with GISS. All below the jump.
The last big task remaining for V2 is a mechanism for doing all this regionally, where spherical harmonics would be inefficient.
GISS comparisonsGISS is of course using somewhat different underlying data - all mine are based on GHCN raw and HADSST2. GISS adds other data, particularly Antarctic, and uses a different HAD SST set to 1981, and an OI set beyond. GISS has recently posted a new explanatory paper.
As I mentioned above, the program now does individual years, so I'll show here 2009 and 2008. Because of lacking GHCN data, I've rubbed out above 80N and below 65S. I've more scientifically matched the GISS colors and levels (some GIMP magic).