A guest post by Nic Lewis The recently published open-access paper “How accurately can the climate sensitivity to CO2 be estimated from historical climate change?” by Gregory et al.[i] makes a number of assertions, many uncontentious but others in my view unjustified, misleading or definitely incorrect. Perhaps most importantly, they say in the Abstract that … Continue reading Gregory et al 2019: Unsound claims about bias in climate feedback and climate sensitivity estimation