During a talk with the Hoover Institute, former government scientist Steven Kooni provided insight into some of the major challenges involved in building comprehensive climate models. As Under Secretary for Science under Obama, he led the Department of Energy’s office overseeing climate research.
Koonin begins by outlining the immense complexity of the climate system as a coupled non-linear chaotic set of components including the atmosphere, ocean, cryosphere and biosphere. He explains this makes the initial conditions extremely sensitive over time, so even small errors in how processes are represented can accumulate into large uncertainties when projecting decades or centuries into the future.
As evidence of these uncertainties, Koonin notes that historically, climate models have not accurately predicted the actual temperature evolution over the past 20 years. He suggests this indicates potentially missing physics or insufficient understanding and modelling of natural climate variability on multi-decadal timescales.
Throughout the talk, Koonin stresses that while climate change poses risks, overreliance on a narrow range of models without transparency or consideration of uncertainties could lead policy astray. He advocates that continued evaluation of projections against real-world observations is essential to improving the representation of key feedbacks and interactions over different time horizons.
Koonin also questions basing drastic economic decisions primarily on the IPCC’s likely range without acknowledging less probable outcomes or natural factors beyond human influence. He argues more interdisciplinary research is still needed to reduce uncertainties before making commitments that could significantly impact energy systems for decades. The talk highlights remaining gaps in scientific understanding that warrant a more comprehensive evaluation of model limitations.
Photo by Greg Rosenke
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