by C. Morrison, March, 28, 2026 in WUWT in NATURE

The climate science world (‘settled’ division) is in shock following the discovery in ancient ice cores that levels of carbon dioxide remained stable as the world plunged into an ice age around 2.7 million years ago. Levels of CO₂ at around 250 parts per million (ppm) were said to be lower than often assumed with just a 20 ppm movement recorded for the following near three million-year period. In addition, no changes in methane levels were seen in the entire period. Massive decreases in temperature with occasional interglacial rises appear to have occurred without troubling ‘greenhouse’ gas levels, and this revelation has caused near panic in activist circles.

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Critics seeking to downplay ice core evidence often suggest it is too imprecise to provide a wholly accurate record of gas levels and temperature. But it is accurate enough to give a broad cyclical insight. It remains the source of some of the best data we have on the past climate. It is undoubtedly more accurate than most proxy evidence from millions of years ago. But whatever the evidence used, it is hard to detect any obvious and continuous link between CO₂ and temperature across the entire geological record going back 600 million years to the start of abundant life on Earth. Certainly none to justify the political notion that humans control the climate thermostat by burning hydrocarbons.

In fact the evidence is so slim that Les Hatton, Emeritus Professor in Computer Science at Kingston University, was recently able to determine from ice core records that 100-year rises of 1.1°C in the current interglacial, which started 20,000 years ago, have occurred in one in six centuries. Going back 150,000 years, the frequency was around one in six to one in 20 centuries. None of these findings suggest that current warming is either unusual or primarily caused by human activity. Needless to say, none of these findings trouble the headline writers in narrative-addicted mainstream media.