Comment on “On the Relationship Between Probabilistic and Deterministic Skills in Dynamical Seasonal Climate Prediction”

Abstract

Yang et al. (2018, https://doi.org/10.1029/2017JD028002 ) derived an integral form for the relation between the resolution component of the Brier skill score and anomaly correlation for joint‐Gaussian‐distributed forecasts and observations. The purpose of this comment is (i) to connect those findings with other studies that have examined theoretical relations between probabilistic and deterministic skill and (ii) to provide a simple closed‐form approximation for the relation. Improved understanding of the Brier skill score (BSS) used in seasonal climate forecasts also improves understanding of the Ranked probability skill score (RPSS) A simple closed‐form approximation summarizes the relation of anomaly correlation with BSS and RPSS for reliable, joint‐Gaussian‐distributed forecasts and observations