Temperature records broken in TempLS October

I've been following some very large spikes in the NCEP/NCAR index during October, with an eventual rise of about 0.2°C. Then followed big rises in the satellite indices, with UAH up about 0.18°C and RSS up 0.07. Here is the first surface index. TempLS mesh (report here) rose by 0.21°C, and TempLS grid by 0.03°C. There is rather a contrast here, which I'll say more about. However, TempLS grid had drifted well ahead of mesh, so this represents a degree of catch up. The result is that both are the hottest month (of all months) in their respective records, by quite a long way (plots below).

The reason for disparity seems to involve SST, and maybe sea ice. TempLS grid uses lat/lon grid cells, and has several without data. In this respect is resembles HADCRUT and NOAA, and often follows them closely. TempLS mesh has a full triangular mesh, so interpolates everywhere, more like GISS. In October, you can see a breakdown of the contributions to TempLS Mesh in the report (scroll down). A main feature is the reversal of Antarctica from cold to warm. The grid methods underweight this.

A paradox is that most indications are that SST did not rise. HADSST shows a small decrease. TempLS mesh shows an increased contribution from SST.

You can see the regional patterns in the report, and in more detail here. Antaarctica and Australia were big hotspots. Brazil is still missing. The heat in Australia is noted here.

So what does this all mean? I think there will be substantial rises in the main indices, setting more records for hottest anomaly. The rises probably won't be as high as the reanalysis, since SST will be a larger damping component. Below the fold, I'll show plots of the last 20 years of TempLS monthly, and a WebGL global plot of the differences going from September to October. Again Antarctica and Australia are the big factors.

Here is TempLS mesh



October stands out, though in TempLS there was also a big spike in 1998 - more so than in other indices. Here is TempLS grid:



Obviously the rise from September is less, but it followed a larger earlier build up. Now here is the WebGL gadget. It shows, in color shading, the changes going from September to October. Again Antarctica and Australia stand out, with seemingly no change in SST. SST changes are small and fairly even, so they tend not to show on the scale of the more volatile land. Europe cooled, central Asia warmed. As usual, the global is a trackball - right mouse button to zoom.