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A Brief Summary Of How ‘Global Warming’ Science Has Changed Since 1998


Two weeks before Dr. Michael E. Mann and colleagues published their 23 April 1998 “hockey stick” chart in Nature, a peer-reviewed journal published a paper asserting “an overwhelming majority of climate scientists” (50 out of 60) view catastrophic human-caused global warming – and even global warming itself – as an “unsupported assumption”.

At the time, satellite data indicated the lower troposphere had cooled by 0.13°C between 1979 and 1994. The Arctic had cooled by -0.88°C since the 1940s.

It was thought the IPCC had just (1995) perpetrated a “disturbing corruption of the peer-review process” in manipulating the conclusions of scientists to support favored government policies.

Image Source: Gardner, 1998

As of 1994 there was still so much uncertainty in the global temperature record that the 1995 IPCC report suggested the estimated warming since the mid-19th century was somewhere between 0.3 and 0.6°C, or about 0.45°C (IPCC TAR 2001).

Just 6 years later the IPCC emphasized a newly fangled certainty and precision in identifying global temperature trends. The “best estimate” was the Earth had warmed 0.61°C from 1861 to 2000.

Image Source: IPCC TAR 2001

In 2015 there were still scientists insisting there had been “no discernible warming since about 2000” (Dai et al., 2015).

Image Source: Dai et al., 2015

By 2019 – just four years later – it was claimed the globe had warmed 1.2°C since the 19th century and the IPCC warned the Earth has 12 years left (2030) to avert a “climate catastrophe” (Gunningham, 2019).

Image Source: Gunningham, 2019


Other ways climate change has changed.

Watch Now: Climate Depot’s Morano at CPAC panel: Warmists have gone ‘wacky’ – ‘Do you want to know how global warming is faring? They now want you to look at rape statistics, at crime statistics, vehicle theft statistics, whether your local Chipotle is serving guacamole’