Abstract
It is well known that the path to greater precision in physics is not smooth. Because differences in subsequent experiments often fall outside the nominal uncertainties of the prior art, science often has to deal with discordance that stimulates increased focus on what were presumed to be small effects. Examples include the history of measurements of ‘Big G’ (the gravitational constant) and the charge of the electron (Bailey, 2018). In climate science, numerous examples can also be found, ranging from the ‘global cooling’ inferred from new satellite measurements in the 1990s, estimates of the mass balance of Antarctica in the 2000s, and the increased spread of climate sensitivity in the latest CMIP6 model intercomparison. Resolutions for these discordant results are not predictable a priori - systematic issues can affect new measurements and old measurements alike, and comparisons may not be fully compatible. While resolutions are still pending though, the broader community may not have the luxury of simply waiting for the reasons to be discovered. I will discuss how and why the climate science community is dealing with the “climate sensitivity issue” in the meantime.
