An assessment of Earth’s climate sensitivity using multiple lines of evidence
Quantifying ECS is challenging because the available evidence consists of diverse strands, none of which is conclusive by itself. This requires that the strands be combined in some way. Yet, because the underlying science spans many disciplines within the Earth Sciences, individual scientists generally only fully understand one or a few of the strands. Moreover, the interpretation
of each strand requires structural assumptions that cannot be proven, and sometimes ECSmeasures have been estimated from each strand that are not fully equivalent. This complexity anduncertainty thwarts rigorous, definitive calculations and gives expert judgment and assumptions apotentially large role.