Comments on temperature-extreme precipitation scaling: A two-way causality?

Recently, Barbero et al. (2018) examined temperature-extreme precipitation scaling and argue that the local cooling effect leading to negative apparent scaling in Darwin found by Bao et al. (2017a) was simply a statistical artefact. Barbero et al. (2018) also propose that dew point temperature drives extreme precipitation, and should be used as a scaling variable. Here we address some of their criticisms and further clarify some conclusions. We maintain that scaling analyses via binning methods cannot be reliably applied to climate changes due to fundamental problems of misinterpreted causality, and that using dew point temperature does not solve these problems.