ENSO Rossby wave sources (ENSO_RWS) diagnostic package consists of four levels. With a focus on identifying leading processes that determine ENSO-induced global teleconnection, particularly the Pacific North American (PNA) pattern, main module of the POD estimates basic state flow properties at an appropriate tropospheric upper-level and solves barotropic vorticity equation to estimate various terms that contribute to the total anomalous RWS. In that pursuit, POD is applied to monthly data (climate model or reanalysis products), and RWS terms are estimated for “composite” El Niño or La Nina events. To attain robust “composite” results a reasonable sample of ENSO winters is needed. However, the POD can be applied even for a single El Niño winter (e.g., when applied to seasonal prediction models). Similarly, the POD is applicable to any number of pressure levels (e.g., to identify the level at which maximum upper-level divergence and associated RWS are located). Here, reanalysis products (e.g., ERA-interim) is “considered” as “observations” and diagnostics obtained from ERA-Interim and other reanalysis products are used for model validation. In this general document, brief descriptions of the four levels of the POD are provided but detailed information is provided at each level. For the four levels of diagnostics, selected results are illustrated here.
Documentation and Contact Information
ENSO Rossby wave diagnostics