Guest essay by Rud Istvan
The disclosures by Dr. Bates concerning Karl’s ‘Pausebuster’ NOAA NCEI paper have created quite the climate kerfuffle, with Rep. Smith even renewing his NOAA email subpoena demands. Yet the Karl paper actually is fairly innocuous by comparison to other NOAA shenanigans. It barely removed the pause, and still shows the CMIP5 models running hot by comparison. Its importance was mainly political talking point pause-busting in the run up to Paris.
Here is an example of something more egregious but less noticed. It is excerpted from much longer essay When Data Isn’t in ebook Blowing Smoke. It is not global, concerning only the continental United States (CONUS). But it is eye opening and irrefutable.
NOAA’s USHCN stations are used to create the US portion of GHCN. They are also used to create state-by-state temperature histories accessible on the NOAA website. A 2011 paper announced that NOAA would be transitioning to updated and improved CONUS software around the end of 2013. The program used until the upgrade was called Drd964x. The upgrade was launched from late 2013 into 2014 in two tranches. Late in 2013 came the new graphical interfaces, which are an improvement. Then about February 2014 came the new data output, which includes revised station selection, homogenization, and gridding. The new version is called nClimDiv.
Here are three states. First is Maine, with the before/after data both shown in the new graphical format.
Second is Michigan, showing the graphical difference from old to new software.
And finally, California.
In each state, zero or very slight warming was converted to pronounced warming.
One natural question might be whether upgraded homogenization (among other things ‘removing’ urban heat island (UHI) effects) is responsible? No from first principles, because the NOAA/NASA UHI policy is to warm the past so that current temperatures correspond to current thermometers (illustrated using NASA GISS Tokyo in the much longer book essay). This might be appropriate in California, whose population more than doubled from 1960 to 2010 (138%) with current density ~91 people/km2. Maine represents a similar ocean/mountain state, but is much more rural. Maine’s population grew by only a third (34%) from 1960 to 2010, and its current population density is just 16.5 people/km2. Maine should not have the same need for, or degree of, homogenization adjustment. Without the newest version of the US portion of GHCN, Maine would have no warming; its ‘AGW’ was manufactured by nClimDiv.
It is possible albeit tiresome to analyze all 48 CONUS states concerning the transition from Drd964x to nClimDiv. NOAA gave 40 out of 48 states ‘new’ AGW. The Drd964x decadal CONUS warming rate from 1895 to 2012 was 0.088F/decade. The new nClimDiv rate from 1895 to 2014 is 0.135F/decade, almost double. Definitely anthropogenic, but perhaps not actual warming.
 Fennimore et. al., Transitioning…, NOAA/NEDIS/NCDC (2011) available at ftp.ncdc.noaa.gov/pub/data/cmb/GrDD-Transition.pdf