Is Canada's 'warming' just politically driven data corruption?

Hickey explains:

I sent figures showing the 1998 step-increase feature in the temperature records of many AHCCD stations to the Environment Canada researchers responsible for creating the AHCCD in emails in June and July of 2021, when I was employed as a data scientist at the Bank of Canada. These emails have since been obtained via an Access to Information (ATI) request to Environment Canada.

…In her responses, Vincent [senior Environment Canada Research Climatologist Dr. Lucie A. Vincent] did not provide an explanation for the 1998 step-increase feature, but rather stated she had 'quickly checked the metadata [data before adjustment and homogenization] for some of the stations' and, on that basis, affirmed that the step-increase feature would not have been caused by the introduction of automated weather stations during the 1990s. In her final response, Vincent stated that '[w]e have not detected a positive shift around 1998 in the annual mean temperature of the selected stations due to automation or any other non-climatic causes' and that '[t]his shift [the 1998 step-increase feature] identified visually when the time series is focused on the 1960-2020 period is probably due to climate variability only.'

"Probably?" So, Canada is spending hundreds of billions of dollars largely based on data that the government scientist most involved in its generation can only say is "probably" indicative of real warming? Something she confirmed in part through "quickly checking the meta data." And, removing that questionable step change results in practically no real warming at all?Showing the map below in his report, where blue circles represent locations of cooling, and red warming, Hickey points out: "If anything, the two-decade trend in annual average temperature series for many AHCCD stations is negative post-1998."

Citing numerous references from the scientific literature, Hickey explained in detail to Vincent in follow-up emails that the sharpness of the temperature increase and its magnitude indicate that it is notdue to real climactic change. He also laid out a detailed analysis of potential sources of the artifact in his report, which could include land use changes and instrumentation changes. Both of these could easily cause a 1-degree shift in the temperature data. Moreover, he explained, "there are no other similar large and geographically widespread discontinuities in the AHCCD dataset at other years."

Meaningfully, Hickey concludes in his Dec 23^rd report (my bold):

The 1998 step-increase feature in the annually-averaged temperature time-series for many Canadian stations was therefore left essentially unaddressed by Environment Canada, and remains in place in the AHCCD dataset to this day, including in the 4th generation of the data,...

Hickey was not the only Bank of Canada employee to find fault with ECCC's temperature data. He writes:

On December 7, 2020, Bank of Canada Economist Julien McDonald-Guimond sent an email to Environment Canada researchers with an inquiry about the 2nd generation AHCCD daily temperature records, noting he had found some cases in which the daily minimum temperature (Tmin°) was greater than the daily maximum temperature (Tmax°) for the same day and for the same AHCCD station.

In fact, there were more than 10,000 instances of days for which the daily minimum temperature was greater than the daily maximum temperature, in the 2^nd generation of the AHCCD. Hickey writes (my bold):

McDonald-Guimond sent a second email on December 9, 2020 with an attached table listing the instances of Tmin° > Tmax° that he had found…The attachment to McDonald-Guimond's December 9, 2020 email, which Environment Canada's Access to Information office initially failed to include in its release, was eventually provided...McDonald-Guimond's table contains 10,159 instances of daily temperature records with Tmin°>Tmax°. Affected records occurred in all Canadian provinces and territories.

A histogram of the differences Tmin° – Tmax° for the 10,159 instances shown in McDonald-Guimond's table is shown in Figure 10 [below].

For the 10,159 instances, the median difference between Tmin° and Tmax° was 0.80°C (vertical red line in Figure 10), the average difference was 1.21°C, and the maximum difference, which was for Cape Dorset, Nunavut, on February 25, 1995, was 30°C." [my bold]

Environment Canada Climate Data Analyst Megan Hartwell replied to McDonald-Guimond on January 13, 2021 that "We [ECCC] were quite surprised by the frequency of the issue you reported, and have taken some time to go through the data carefully."

That ECCC were surprised by McDonald-Guimond's finding is cause enough to worry. But the fact that they now "have taken some time to go through the data carefully" begs the question: didn't they go through the data carefully before releasing it the first time? Hartwell's excuse that the homogenized data has since been updated to a later version, while admitting that "the AHCCD site-page has not been updated yet and does not introduce the third generation…" hardly boosts public confidence.

This situation is far too complicated to be explained fully in a brief article such as this, so I encourage interested parties to read Dr. Hickey's December 23, 2025report and judge for yourself if we can trust ECCC's claim that the increase in Canada's average temperature (a specious parameter to begin with) is anything close to the amounts they claim, and on which the government of Canada is basing multi-billion dollar climate policies.

When this apparent blunder is finally fixed, government scientists should be compelled to publish the corrected results just as prominently as they announced their initial findings. And, in the meantime, we should be grateful that experts like Hickey and McDonald-Guimondare prepared to engage in skeptical inquiry of their government peers about data that has contributed to climate policies that we all pay for.