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Restoring Scientific Debate on Climate

by Jim Steele, Oct 3, 2020 in WUWT

The political genius of Abraham Lincoln’s efforts to unify the country during America’s most divisive time has been attributed to assembling a “team of rivals”. Likewise, scientific research is published so rivals and supporters of a hypothesis can independently and critically examine it. The great benefits of a team of rivals is also the basis for convening red team/blue team debates.

In 2017, Dr Steve Koonin, a physicist who served as Obama’s Undersecretary for Science in the US Department of Energy, urged convening red-team blue-team debates for climate science in his article A ‘Red Team’ Exercise Would Strengthen Climate Science.  “The national-security community pioneered the “Red Team” methodology to test assumptions and analyses, identify risks, and reduce—or at least understand—uncertainties. The process is now considered a best practice in high-consequence situations”.

Unfortunately, the public climate science debate has been framed as “deniers” versus “alarmists”, or “honest saintly scientists” versus “corrupt perpetrators of a hoax”.  The media pushes exaggerated claims of a crisis while some scientists misleadingly shield their hypotheses claiming the “science is settled”.  But science is a process and never settled. However, all sides do agree carbon dioxide is a greenhouse gas and concentrations have increased. All sides agree the climate is changing. That science is indeed settled. But complex climate dynamics are not driven solely by CO2 and many unsettled questions remain.  Scientists still debate whether climate has a higher or lower sensitivity to rising CO2. Answering that question depends on the unsettled science regards competing contributions from natural variability and landscape changes. And because rising CO2 and warmth benefits photosynthesizing plants, scientists debate the beneficial contributions of rising CO2.

Climate models could not replicate recent warming when only natural climate change was considered. But models could simulate recent warming since 1970s after adding CO2. That was the only evidence that supported the notion that increasing CO2 caused observed warming. However, there’s a flaw in such reasoning. Models limited to just natural climate dynamics failed to explain recent changes simply because our understanding is still incomplete. For example the Pacific Decadal Oscillation, a major driver of natural climate change was only recently characterized in 1997, but has been shown to account for 100 years of changing climate along the coasts of the north eastern Pacific.


Urban Heat Island profile Image from Lawrence Berkeley Labs