Thursday, May 14, 2020

GISS April global down by 0.03°C from March.

The GISS V4 land/ocean temperature anomaly was 1.16°C in April 2020, down from 1.19°C in March. That compares with a 0.054°C rise in the TempLS V4 mesh index.

There is a recent oddity with GHCN V4 monthly, in that in the last 24 hours a lot of station data has gone missing. This has happened before, and gets fixed (thanks, GHCN). It shows an effect in Moyhu data in a disagreement between the report data and the overall table. The latter uses the current data with gaps. I hope that GISS has not been affected by this. My reporting system rejects new data if the total number of stations reduces by more than a small threshold.

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 LOESS-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 comment:

  1. I update my prediction for GISS temperature anomaly using data up to Apr20.
    MAM20 1.14+-0.05
    JJA20 0.95+-0.12
    SON20 1.04+-0.15
    J-D20 1.07+-0.08
    DJF21 1.07+-0.26

    Now the prediction gives a more as 90 % chance of a new record this year.