Friday, April 7, 2017

March global surface temperature down 0.066C.

Update There was a major revision to GHCN China data, and now March was 0.03°C warmer than February. See update post

TempLS mesh declined in March, from 0.861°C to 0.795°C. This follows the very small drop of 0.01°C in the NCEP/NCAR index, and larger falls in the satellite indices. The March temperature was still warm, however. It was higher than January (just) and higher than any month before October 2015. And the mean for the first quarter at 0.813°C is just above the record high annual mean of 0.809°C, though it could easily drop below (or rise further) with late data. So far all the major countries seem to have reported. With that high Q1 mean, a record high in 2017 is certainly possible.

TempLS grid also fell by a little more by 0.11°C. The big feature this month was the huge warmth over Siberia. It was cold in Canada/Alaska (but warm in ConUS) and cold in China. Here is the map:

The breakdown plot is remarkable enough that I'll show that too here (it's always on the regular report). On land almost all the positive contribution came from Siberia and Arctic - without that, it would have been quite a steep fall. SST has been slowly rising since December, which is another suggestion of a record year possibility.

Incidentally I'm now using the finer and more regular SST mesh I described here. The effect on results is generally small, of order 0.01-02°C either way, which is similar to the amount of drift seen in late data coming in. You may notice small differences in comparing old and new. You'll notice quite a big change in the number of stations reporting, which is due to the greater number of SST. I've set a new minimum for display at 5300 stations.


  1. The AGU-2016 ENSO El Nino model is based completely on the long-period lunar tidal cycles reinforced by seasonal cycle impulses. It works so well that it detects the measured variations in the length of the various lunar months. For example, the model will isolate the beat and phase in the Draconic month length described here rather precisely. Whats interesting is that the same numerical techniques used for modeling ocean tides are applied, but with a different concept for seasonal reinforcing. The model therefore has gone from being an explanation of the ENSO behavior to a sensitive metrology technique for measuring the lunar and solar cycles. Not the first time that I have done this with what seem to be strange physical phenomena. That's the way you substantiate a model's veracity -- flip it from a question of over-fitting to one of precisely identifying physical constants.

    So its just a matter of time before these erratic variations of temperature caused by ENSO are nailed down completely.

  2. All of a sudden, TempLSmesh for March has gone up to 0.89 C, 0.03 above Feb.
    I am not sure, but I think China caused it, changed from cold blue to neutral white on the map yesterday

    1. Olof,
      Yes, I'll check. As I recall, there were results from China before. Maybe one of those cases where they sent in the wrong month.

    2. Yes, I think that is the explanation. I looked at the TMAX file, dated 8 April. The Feb and Mar numbers are very similar, and all have a P flag, meaning source climat - other months have a K flag (UK). I looked at the first, HAILAR reports now a max of -3C, but the 8 Apr GHCN file says -13.5, which was the Feb max. So, in summary, they submitted the Feb data instead of Mar, then corrected it.