Tuesday, July 17, 2018

GISS June global down 0.06°C from May.

The GISS land/ocean temperature anomaly fell 0.06°C last month. The June anomaly average was 0.77°C, down from May 0.83°C. The GISS report notes that it is the equal third warmest June in the record. The decline contrasts with the virtually unchanged TempLS; the NCEP/NCAR index declined a little more. Satellite indices both rose a little.

The overall pattern was similar to that in TempLS. Very warm in N Central Siberia and Antarctica. Warm in most of N America, and also in Europe and Middle East. Rather cold in S America and Arctic.

As usual here, I will compare the GISS and previous TempLS plots below the jump.

Here is GISS

And here is the TempLS spherical harmonics plot

This post is part of a series that has now run for six years. The GISS data completes the month cycle, and is compared with the TempLS result and map. GISS lists its reports here, and I post the monthly averages here.
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


  1. Sort of interesting symbolically, the GISS annual average for 2016 has now hit 1.0ºC for the first time.

    1. Also, according to Wood for Trees, the GISS L&O 30-year trend is now .19 ℃ per decade.

    2. Note that the GISS average is also relative to 1951-1980, so compared to preindustrial, more than 1.0 degrees (probably more like 1.25 degrees).

      And according to the Cowtan widget (http://www.ysbl.york.ac.uk/~cowtan/applets/trend/trend.html), the 30 year trends are 0.20 degree C/decade for Berkeley and HadCRUT. I'll also note that the GISS trend of 0.19/decade can be extended as far back as 1974, or 44 years.