Global Temperature Report – April 2014
By Paul Homewood
| RSS | UAH | HADCRUT4 | GISS | |
| April 2014 | 0.25 | 0.19 | 0.64 | 0.73 |
| Change from last month | +0.04 | +0.02 | +0.10 | +0.03 |
| 12 month running average | 0.20 | 0.22 | 0.51 | 0.64 |
| Average 2004-13 | 0.23 | 0.19 | 0.47 | 0.59 |
| 12 month average – 1981-2010 Baseline | 0.10 | 0.22 | 0.22 | 0.24 |
As noted below, these figures are anomalies, and each set uses a different baseline period, from which to calculate these. Therefore, to introduce some consistency, I have added an extra line, showing the 12-month running average, using a uniform baseline of 1981-2010 (the one used by UAH).
As can be seen, RSS and GISS are at the two extremes.
There has been a sizeable divergence between satellite and surface datasets in the last couple of months. The table below shows the increase from the 2013 annual figures to April 2014.
| RSS | UAH | HADCRUT4 | GISS | |
| 2013 Annual | 0.23 | 0.19 | 0.49 | 0.61 |
| April 2014 | 0.25 | 0.19 | 0.64 | 0.73 |
| Increase | +0.02 | ZERO | +0.15 | +0.12 |
It remains to be seen whether the satellite numbers follow the surface ones in due course, or if the latter fall back.
Notes
UAH and RSS are the two satellite datasets, that measure temperatures in the lower troposphere, from the surface up to about 8000 metres. The HADCRUT and GISS datasets measure surface temperatures.
All temperatures are presented as anomalies, i.e the difference, measured against a baseline, that is different across all four sets. (This means that the anomalies are not directly comparable between sets)
The baselines used are:
RSS – 1979-98
UAH – 1981-2010
HADCRUT – 1961-90
GISS – 1951-80
HADCRUT is maintained the UK Met Office’s Hadley Centre in conjunction with the Climatic Research Unit at the University of East Anglia.
GISS is run by the Goddard Institute for Space Studies at NASA.
UAH is the University of Alabama in Huntsville, and their dataset is part of an ongoing joint operation with NOAA and NASA.
RSS is a scientific research company, Remote Sensing Systems.
Sources
1) RSS
2) UAH
http://vortex.nsstc.uah.edu/data/msu/t2lt/uahncdc_lt_5.6.txt
3) HADCRUT
4) GISS
http://data.giss.nasa.gov/gistemp/tabledata_v3/GLB.Ts+dSST.txt
UPDATE
Please not the RSS 12 month average on 1981-2010 baseline has been corrected.
Comments are closed.
NOT A LOT OF PEOPLE KNOW THAT 
Paul, great info as usual. There are two data sets for the UAH graph here. Was that posted in error? Thank you
Thanks, sorted.
Paul
Thank you. Love your work!
I still think that for the sake of completeness, you should include NCDC/NOAA figures.
The trouble is that, while it is easy enough to get individual monthly numbers, I have not found any way to download the whole database.
As it stands, I would have to load it month by month.
The database is here. Any suggestions would be welcome!
http://www.ncdc.noaa.gov/cag/time-series/global
I know what you mean.
The messed about with the site and it isn’t easy to find any more.
Try this;
https://www.ncdc.noaa.gov/monitoring-references/faq/anomalies.php
Use CSV format.
Thank you for providing such a summary update Paul, very useful.
Would it be possible to incorporate standard deviation within summary tables for context within future updates?
Also, I understand why 1981-2010, i.e. WMO recommended 30 year period, is used for the anomaly baseline, but in the context of the 60 year oscillation, and late 20th century warming as the warming leg of the 60 year oscillation (plus perhaps reduced albedo due to reduced soot particulates, esp. in the west), we would expect positive anomalies using that baseline, and of course you know that; indeed your inclusion of plots of the temperature datasets, after late 20th century warming, is perfect.
The Met Office say – The global average temperature in 2014 is expected to be between 0.43 °C and 0.71 °C above the long-term (1961-1990) average of 14.0 °C, with a central estimate of 0.57 °C, according to the Met Office annual global temperature forecast.
With the large increase in HC4 in April, I make the cumulative WMO average for 2014 to be 0.52c, up from 0.48c in March.
Maybe the MO forecast will be correct for once!
Thanks, Paul. Great summary.
It would seem there’s not a single global temperature record that supports any warming since 2002.
Paul,
Re the top table, are you sure about the 12 month (1981-2010) average for RSS?
I make the 1981-2010 RSS average 0.10. Deducting this from April 2014 gives 0.15 (0.25 – 0.10); but I make the adjusted average of the past 12 months (May 13 – Apr 14) in RSS 0.11, not 0.15. I may be wrong, but it might be worth re-checking.
P.S. you can get the NOAA monthly figures from the ‘Anomalies and Index Data’ link at QV’s link above.
Thanks David, you’re right.
I also get 0.10C for 1981-2010, so I must have been looking at the April anomaly of 0.25C.
I’ll amend. ( I actually get 0.104C for the last 12 months).
No problem. I get 0.107 on my stored data. We’ll hardly fall out over that one!
I also get 0.24 for NOAA, by the way. If you add that to your table it’s clear that there’s a significant anomaly between RSS and ‘all’ the other producers, including UAH.
Something tells me this is due to more than just a spatial coverage issue.
Your 12-month averages look like they are not centred on the display position, can I suggest that that might be better, though of course the latest data would get less averaging as you move towards NOW.