At the beginning of 2023, NOAA once again changed historical measurements in their surface temperature dataset.
This is a common action that NOAA applies way too frequently to historical information, which one could surmise, based on the following evidence, does not comport with the scientific goal of objectivity and truth.
Climatologist and scientist Ole Humlum is one of the few experts who has been tracking the temperature changes made by NOAA since 2008. In his monthly update, Dr. Humlum includes the below charts that aid in the visualization of NOAA's "scientific" adjustments.
This chart tracks the changes made to two calendar months, specifically January 1915 and January 2000.
For the month of January 2000 (red lines), modifications have now reached 70+ occurrences (each vertical line represents a change). Some changes are large, but most are small.
For the month of January 1915 (the blue lines), its temperature has been modified by NOAA 65+ times through April 2023
At the starting point of Dr. Humlum's tracking efforts, May 2008, the difference between these two Januarys was +0.39°C. That difference had reached +0.51 °C by April 2023.
Now, if these two Januarys were the only months modified by NOAA, it would be no big deal.
BUT, as Holum's second chart indicates, NOAA applies changes to all months going back to 1880. And the vast majority of changes since 1939 have been temperature increases, while those prior to 1940 were decreases.
Overall, NOAA has fabricated an increased warming rate since 1939 and has cut the warming rate in half from 1880 through 1939.
All accomplished via continuous adjustments since May 2008, which conveniently produce greater global warming for the modern era.
In the case of the most recent changes to the historical measurements made in January 2023, 1,575 of 1,716 past monthly temperatures reported in December 2022 were "updated"—91.8% overall.
For the decade of the 1880s, 114 months out of 120 were changed—that's 95%. The average monthly change for that decade was a cooling of -0.04°C. Those changes included June 1883 being cooled by a whopping -0.17°C.
As stated earlier, these changes to the historical temperatures do not appear to comport with unbiased objectivity or scientific truth. Instead, they seem very biased, with a non-randomness designed to support a political narrative—aka, "the climate crisis".
Note: Ole Humlum's charts include the acronym 'NCDC' - (NOAA's National Climate Data Center)