Just under a year ago, on July 19, 2013, I asked the question, What Is The Greatest Scientific Fraud Of All Time?   After going through a number of candidates (e.g., the Tasaday, Piltdown Man) I concluded:

[G]oing through these lists also makes clear that none of these frauds comes close to the big one going on right now, which is the world temperature data tampering fraud.

The world temperature data tampering fraud is the fraud whereby the official U.S. government guardians of temperature data, namely NOAA/NCDC and NASA/GISS, systematically adjust older temperatures down and newer temperatures up in order to introduce spurious warming trends into the data and thereby support the narrative that "global warming" is occurring.

Some people who are following and reporting on this story are still avoiding the use of the word "fraud."  I am not.  

When I wrote the July 2013 post, this story was still struggling for attention.  A very energetic guy who blogs at Real Science under the name Steven Goddard (actual name: Tony Heller) was writing post after post comparing recent temperature data on government websites to previous versions, and noting example after example of downward adjustments of the past and upward adjustments of the more recent data.  However, some had criticized his work for occasional inaccuracies or errors.  Joseph D'Aleo of the icecap.us website had also entered the fray with several examples of unexplained adjustments.  But otherwise the story has been largely quiet in the intervening year.

That all ended a couple of weeks ago.  Over a period of a few days, several wide circulation sites, and even a television news show, featured some of Goddard's work.  It had lead position on Drudge for a day.  Steve Doocy of Fox and Friends had a segment based on Goddard's work where he stated "NASA scientists fudged the numbers to make 1998 the hottest year to overstate the extent of global warming."  Other sources picking up the story included the Telegraph, Breitbart, and realclearpolitics.

Next, politifact decided to weigh in.  They went to the usual suspects of the "mainstream" climate community, including the director of NASA/GISS, Gavin Schmidt.  These usual suspects engaged in the usual obfuscatory handwaving, attributing various of the adjustments to seemingly legitimate things like station moves and changes in the time of day at which thermometers are read.  Politifact fell for it, rating Doocy's Fox News piece "pants on fire."

But by this time the story was getting so much play that lots of people were starting to pay attention.  A guy named Paul Homewood of the website notalotofpeopleknowthat was intrigued enough to pick one station at random in Texas and do a deep dive into the data. His resulting post on June 26 is titled "Massive Temperature Adjustments at Luling, Texas."  His conclusion:

[T]he adjustments have added an astonishing 1.35C to the annual temperature for 2013.  Note also that I have included the same figures for 1934, which show that the adjustment has reduced temperatures that year by 0.91C.  So, the net effect of the adjustments between 1934 and 2013 has been to add 2.26C of warming.

Then Joe D'Aleo weighed in with some data from Maine.  In 2013 he had downloaded NCDC annual temperature data for Maine.  Then NOAA earlier this year announced a transition to a new so-called CLIMDIV version of its USHCN data for Maine, so D'Aleo downloaded that for comparison to the version he had downloaded last year.  How did the two compare?  While the old data showed no warming in a record going all the way back to 1895, suddenly there was a large warming trend.  And where did it come from?

The new CLIMDIV data was supposed to resolve issues with recent station moves, transition to airport, to new MMTS technology and UHI and siting issues with improvements late in the record, we were very surprised to see the biggest changes to the early data set.  1913 went from the warmest year in the record to the middle of the pack with a cooling of close to 5F!.

So kindly, Dr. Schmidt, can you explain exactly how a change to the time of day at which temperatures are read has now made 1913 5F cooler in Maine than it was previously?

On June 28 the highly respected Judith Curry of Georgia Tech weighed in with a post titled Skeptical of skeptics: is Steve Goddard right?  I have previously noted that Curry, once a member of the climate science in crowd, has become increasingly unaccepting of the unscientific antics of the climate science community.   Her conclusion after reviewing Goddard, Homewood and others:  

I infer from this that there seems to be a real problem with the USHCN data set, or at least with some of the stations. . . .  As far as I can tell, NOAA has not responded to Goddard’s allegations. Now, with Homewood’s explanation/clarification, NOAA really needs to respond.

On June 29, there was a lengthy post by Anthony Watts of wattsupwiththat, titled NOAA's temperature control knob for the past, the present, and maybe the future - July 1936 now hottest month again.  Anthony did some looking at yet more data, and every place you look the story comes up the same.  For example, Anthony asked a guy named Bruce at Sunshine Hours to gather data on Kansas and plot it on some maps, which then appear in Anthony's post.  Example of the results:

Bruce also plotted some other maps of Kansas, for July 1936, and for July 2012. Note how in July 1936 the Tmax temperature are almost all adjusted cooler, and in 2012, most all Tmax temperatures are adjusted warmer.

Go to Anthony's post for the maps with station by station data.  Anthony then asks:  Whatever happened to just using actual measured data?  There is no justification for this. 

But at the end of his post, Anthony continues to give these people the benefit of the doubt:

I don’t believe this is case where somebody purposely has their hand on a control knob for temperature data, I think all of this is nothing more than artifacts of a convoluted methodology and typical bureaucratic blundering. As I’ve always said, never attribute malice to what can be explained by simple incompetence.

Sorry, but I'm not buying it.  Here are my problems:  (1) Adjustments to the raw data are everywhere, and literally all of them make the past cooler and the present warmer.  (2) There are literally tens of billions of dollars at stake in having a record of increasing temperatures.  Every scientist working in the "climate science" area is dependent on continuation of government science funding in this area totaling as much as $10 billion per year.  Then there are additional massive subsidies for things like green energy.  (3) They won't release all the underlying calculations and computer code behind the adjustments.  My conclusion: There is nothing innocent about this.  This is the IRS deleted emails scandal multiplied by a factor of 100.

Politifact put a series of questions about this to NCDC and Watts has also posted their response here.  The heart:  "our algorithm is working as designed."  No backup, no code, no detailed justification of each change.  And good luck trying to get that.

Repeat:  The Greatest Scientific Fraud Of All Time.