Friday, July 14, 2023

GISS June global temperature up by 0.14°C from May.

The GISS V4 land/ocean temperature anomaly was 1.07°C in June 2023, up from 0.93°C in May. This rise is nearly the same as the 0.142°C rise reported for TempLS.

As with TempLS, June was by a large margin the warmest June in the record - next was 0.92°C in 2022. As mentioned in my last post, I now have on the data page a maintained table of months in descending order to facilitate these comparisons. Here is the GISS monthly average anomaly:

There seems to be ongoing warming, if you let your eye follow the red "23" squares. Since the annual to date is close to the hottest ever, it is likely 2023 will end up on top.

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

Here is GISS V4

And here is the TempLS V4 FEM-based plot

This post is part of a series that has now run for seven 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. Nick, Thanks much for this very clever chart. Obviously it could work without the colo(u)r, but with it, it becomes reaidly understood. I did check a couple of the nmubers to make sure I understood it. I did.

    Nice going.

    1. Thanks, jf
      Yes, the idea is that you can follow the years more easily with color. That's why I think 2023 may well pass 2016. It had had its top months by now, yet the part-year average of 2023 is not much less.

  2. I'd recommend adding Climate Brink ( from Andy Dessler and Zeke Hausfather) to your blog roll - it looks like they are posting once a week, but pretty much all their posts are worth reading (in my opinion).