Another week, another study showing that our official climate data gatekeepers have been exaggerating the extent of “global warming” to make it look more scary, more urgent, more desperately in need of extra funding for our official climate data gatekeepers…
This one, co-authored by meteorologist Anthony Watts (of Watts Up With That?fame) shows that at least half of the “global warming” in the US since 1979 has been fabricated by NOAA.
While satellite records have shown no global warming for at least 18 years, the land based data sets like the ones maintained by NOAA for the US Historical Climate Network (USHCN) continue to show a warming trend.
One reason for this discrepancy, the study suggests, is that NOAA has been cherry-picking its raw data. That is, it has ignored the evidence from those weather stations showing little or no late Twentieth century warming and instead placed undue emphasis on the ones thatdo show warming.
But the ones that do show warming also happen to be the least trustworthy. These are the ones, the study shows, which have been most corrupted by the Urban Heat Island effect – and other environmental factors.
Some, for example, have been surrounded by buildings or had roads built next to them since they were first sited. Others have had airports vastly expand next door to them. What this inevitably means is that their more recent temperature measurements have been running hot – i.e., they have been distorted by factors which have nothing to do with weather or climate.
Yet, bizarrely, these are the ones that NOAA has been using as the basis for its claims about “global warming” in the US.
If, however, you look at those weather stations that haven’t been corrupted – “unperturbed” stations – what you get is US global warming roughly half as much as NOAA claims.
Whether this represents mere incompetence or calculated fraud by NOAA is for future courts to decide. What we do know is that the problem dates back at least to the 1990s when, for some unexplained reason, NOAA decided to halve the number of weather stations used for its official records. Even more mysteriously, the ones it chose to keep tended to show more global warming while the ones it rejected tended to show much less.
This is a point stressed in the new study:
It must be emphasized that the perturbed stations dropped from the USHCN set show significantly lower trends than those retained in the sample, both for well and poorly sited station sets.
Perhaps we should be generous to NOAA and put their decision to favour compromised weather stations over accurate ones down to spectacular stupidity and incompetence.