NCDC Show Why They Cannot Be Trusted
By Paul Homewood
https://www.ncdc.noaa.gov/sotc/service/global/map-land-sfc-mntp/201404.gif
Following my recent post about how sparse global temperature data really is, reader David pointed out that NCDC do offer the statistical margins of error, to go with their monthly results.
For instance, for the month of April 2014, the error margin is +/- 0.08C, with the mid point of 0.77C. (These, of course, are anomalies against a baseline of the 20thC average).
So, there is a 0.16C range of uncertainty, even assuming the sparse coverage is correctly accounted for.
However, NCDC ignore this fact, and are happy to pronounce that:
The combined average temperature over global land and ocean surfaces for April 2014 tied with 2010 as the highest on record for the month, at 0.77°C (1.39°F) above the 20th century average of 13.7°C (56.7°F).
http://www.ncdc.noaa.gov/sotc/global/2014/4
Statistically, they have absolutely no basis at all for such a claim, but still make it.
You can contrast this with, for instance, GISS who at least have the honesty to admit the uncertainty. So, for 2010, they state:
Global surface temperatures in 2010 tied 2005 as the warmest on record, according to an analysis released Wednesday by researchers at NASA’s Goddard Institute for Space Studies (GISS) in New York.
In 2010, global temperatures continued to rise. A new analysis from the Goddard Institute for Space Studies shows that 2010 tied with 2005 as the warmest year on record, and was part of the warmest decade on record.
The two years differed by less than 0.018 degrees Fahrenheit. The difference is smaller than the uncertainty in comparing the temperatures of recent years, putting them into a statistical tie. In the new analysis, the next warmest years are 1998, 2002, 2003, 2006, 2007 and 2009, which are statistically tied for third warmest year. The GISS records begin in 1880.
http://www.giss.nasa.gov/research/news/20110112/
Using the same logic for April 2014, we find that NCDC data classifies April 2014 as being a statistical tie with eight other years, 1998, 2000, 2005, 2007, 2009, 2010, 2011, and 2012. But, of course, this does not carry quite the same weight as “the warmest on record” claim. On the contrary, it emphasises the flatlining of temperatures in recent years.
http://www.ncdc.noaa.gov/cag/time-series/global
One wonders why a supposedly scientific organisation are so reluctant to tell us the unadulterated truth, instead of offering us cheap propaganda.
But then one remembers this is NCDC we are talking about!
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NOT A LOT OF PEOPLE KNOW THAT 
I find it quite a scientific and engineering feat to measure the global temperature using a variety of measuring devices over a range of temperature and get such precision that they can claim an SD of +/- 0.08°C.
As for NCDC doing their climate change bit, climate change is the major mission of every department of the executive branch. The main mission of the Department of Defense is preparing for climate change. The main mission of the Department of State is fighting climate change. NASA is not about putting men into space, they can’t do that now, their mission is climate change and Muslim outreach. So, why would you be surprised that the folks in charge of weather data wouldn’t be doing their bit for advertising climate change?
Bob Greene,
The figure of +/-0.08 deg C is just the mathematical range of uncertainty calculated from the monthly global temperature value.
The monthly global temperature value itself is basically the average of thousands of surface and sea surface temperature records (after adjustment and expressed as an anomaly). The raw data probably arrive mostly at one decimal place precision, but you don’t have to average too many 1 DP figures to obtain a value with many DPs of precision.
NOAA rounds the mean of all the temperature data to 2 DPs and calculates the error margins from that to the same degree of precision. This is what produces such an apparently exact value, but really what other way can they express it?
Paul,
Your point is borne out somewhat by the latest NOAA update (which is another ‘warmest ever’, I’m sure you’ll be impressed to hear): http://www.ncdc.noaa.gov/sotc/global/2014/5
They have quietly revised the April 2014 figure down from 0.77 to 0.74 and at the same time raised 2010 from 0.77 to 0.78. So April 2014 is no longer the ‘joint highest April on record’, yet according to the April summary at NOAA it still is.
I tend to agree with you that NOAA over-hypes the monthly global releases, especially given the large range of uncertainty and the continuous alteration of monthly data.
I suspect that this is a ‘press office’ issue since, as I’ve mentioned before, when you actually read into the technical details of the report, uncertainty margins are made clear.