Tag Archives: HadCRUT

Big warming, or no warming, depending on dataset

The uncertainty of science: Depending on the dataset, the most up-to-date climate data now shows either no warming since 1993, no warming since 1996, or significant warming continuously since then.

On several different data sets, there has been no statistically significant warming for between 0 and 23 years…. Cl stands for the confidence limits at the 95% level.

The details for several sets are below.

  • For UAH6.0: Since August 1993: Cl from -0.006 to 1.810. This is 23 years and 1 month.
  • For RSS: Since December 1993: Cl from -0.008 to 1.746. This is 22 years and 9 months.
  • For Hadsst3: Since December 1996: Cl from -0.022 to 2.162 This is 19 years and 9 months.
  • For Hadcrut4.4: The warming is statistically significant for all periods above three years.
  • For GISS: The warming is statistically significant for all periods above three years.

The quote above lists all the major climate datasets that everyone in the climate field uses. I’ve rearranged the order from the original to put similar datasets together and thus make it easier to digest the information.

The first two datasets are from satellite data. The Hadcrut datasets both use historical ground and sea surface temperature records and are both produced by the Climate Research Unit headed by Phil Jones, who when other scientists asked him for his raw original data in order to check it admitted that he had lost it. Jones was also one of the scientists whose climategate emails revealed a desire to destroy the careers of any skeptics, prevent their work from being published, and an effort to conceal or change data that contradicted the theory of global warming. GISS is the Goddard Institute for Space Sciences, run for decades by global warming advocate James Hansen and now the source of today’s claims that every month of every year is the hottest ever recorded. GISS is also the NASA institute that has been adjusting past datasets to cool the past and warm the present, thus creating a significantly steeper rise in global temperature than is shown by the original raw data.

Of these datasets, three show no significant warming in the past two decades, while two show significant warming. Which is it? Your guess is as good as mine. However, I must point out that the two datasets that show statistically significant warming have both come under question in the past few years because of questionable science practices, which from my perspective makes their conclusions suspect.

Regardless, even if we accept all of these datasets as completely sincere and honestly obtained, they still are in conflict with each other. Under any reasonably scientific analysis, this tells us that the science here is definitely not settled, and that a lot more work needs to be done before anyone can hazard a guess as to what’s going on with the climate.

“There is no statistical case to be made for a global temperature increase in the past 15 years.”

“There is no statistical case to be made for a global temperature increase in the past 15 years.”

The database is the one created by the Met Office in Great Britain. Also this:

None of these adjustments are, considering the errors of measurement, statistically significant, but they do affect the ranking of years, which is important if the associated errors are not considered, as is often the case in the media. The overall conclusion is that global temperature datasets are fluid and change from month to month, and this must be taken into account in any analysis. It would be nice to have explanations for such changes.[emphasis mine]

Because of the unexplained adjustments, 1998 is no longer the hottest year on record, a “fact” trumpeted loudly by global warming scientists for more than a decade.