Friday, July 3, 2015


Data for the Moyhu NCEP/NCAR index is now in. It was a month of contrasts - starting very warm, then cold, and ending somewhat warmer. The end result of 0.204°C (1994-2013 base) puts it similar to January. You can now see the map of average temperatures for the month. Warm in west N America and NE Pacific (strong El Nino pattern), also in W Europe and W/central Russia. Extremes in Antarctica, mostly cold. Cool in E Mediterranean.

As noted here, there is predictable month-month variation associated with choice of anomaly base period. That was partly responsible for the discrepancy between a May rise in the index, and a flat GISS. To try to counter this variation, I have added a section of the table below the monthly indices which tries to put the index on the same anomaly base as GISS or NOAA. It can't do this directly (lacks good data), but can work out that component of the change based on other indices during 1994-2013. IOW, it's the corrected prior estimate for those indices. That estimate is that GISS should be about the same as May (0.72°C), while NOAA should be about the same as April. However, NOAA has been consistently exceeding expectations lately.

Update. Troposphere data: RSS is up from 0.31 to 0.391°C; UAH v6 is up from 0.27 to 0.31.


  1. I think .72C for June would have the first 6 months of 2015 at .758C on GISS, up .078C in six months. It seems unlikely 2015 will not break 2014, and there's a possibility 2016 could rival 2015.

    But I never get ahead of myself.

  2. I would say 0,7°C for giss also in june, based on NCEP. 2015 is far ahead of 2014 for the moment and next months shoud be warmer, so....

  3. I should have said 0,77°C in june for GISS.

  4. I agree on 0.77 for GISS June.
    I guess that GISS May will be adjusted to 0.73 with the inclusion of the missing Byrd station/West Antarctica and Svalbard. These stations represents a large area and were actually much warmer than the GISS infill expectations, about 5-6 and 2-3 C respectively.
    The rise from May to June is about 0.04 C based on 1/3 NCEP/NCAR land and 2/3 ERSST v4.

  5. Yes, according to GISS, "several Antarctic stations were excluded from the analysis on May 13, 2015" and we can see that West Antarctica is warmer on NCEP map that on GISS. 0,73 and 0,71 is not a big difference and that were the temperatures we could except, I think.
    As for june, NCEP shows higher global anomaly that in may. But cold Antarctica, even in the west,and warmer arctic that in may. That's why maybe june will be a bit warmer that may. Antarctica, Arctic and Siberia seem to explain differences between Ncep and Gistemp.
    It would be nice if we could infer a global temperature anomaly from NCEP CFSv2 forecast for NDJ 2015 and DJF 2016. I don't know if it has been done but if you look at those forecasts you might guess the anomaly is quite outsanding.