Wednesday, July 10, 2019

Revised June global surface TempLS up 0.067°C from May.

I made an error in the previously posted TempLS for June. The rise is now 0.067°C instead of 0,096°C. The June anomaly was 0.782°C instead of 0.811°C. The difference in global average is actually small, and 2019 was still easily the warmest June in the record, but by 0.07°C, not 0.1°C.

Although the overall difference is small, the error was major - my calculation used May SST values, not June. Teething problems with the V4 system. Fortunately, the hemisphere effects more or less balanced, but the map looks different. I had noted  earlier that there was a marked hemisphere difference. I did look further into that, which revealed the error, but I should have twigged sooner. Land is unaffected, and so most of my previous comments still hold.

Here is the revised temperature map, using the LOESS-based map of anomalies.

The original map is preserved on my tweet here.

This post is part of a series that has now run since 2011. The TempLS mesh data is reported here, and the recent history of monthly readings is here. Unadjusted GHCN is normally used, but if you click the TempLS button there, it will show data with adjusted, and also with different integration methods. There is an interactive graph using 1981-2010 base period here which you can use to show different periods, or compare with other indices. There is a general guide to TempLS here.

The reporting cycle starts with a report of the daily reanalysis index on about the 4th of the month. The next post is this, the TempLS report, usually about the 8th. Then when the GISS result comes out, usually about the 15th, I discuss it and compare with TempLS. The TempLS graph uses a spherical harmonics to the TempLS mesh residuals; the residuals are displayed more directly using a triangular grid in a better resolved WebGL plot here.

A list of earlier monthly reports of each series in date order is here:
  1. NCEP/NCAR Reanalysis report
  2. TempLS report
  3. GISS report and comparison with TempLS


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