Tropical Cyclone Genesis Potential Indices in a New High‐Resolution Climate Models Ensemble: Limitations and Way Forward

Abstract

Genesis Potential Indices (GPIs) link the occurrence of Tropical Cyclones (TCs) to large‐scale environmental conditions favorable for TC development. In the last few decades, they have been routinely used as a way to overcome the limitations of climate models (GCM), whose resolution is too coarse to produce realistic TCs. Recently, the first GCM ensemble with high enough horizontal resolution to realistically reproduce TCs was made available. Here, we address the questions of whether GPIs are still relevant in the era of TC‐permitting climate model ensembles, and whether they have sufficient predictive skills. The predictive skills of GPIs are assessed against the TCs directly simulated in a climate model ensemble. We found that GPIs have poor skill in two key metrics: inter‐annual variability and multi‐decadal trends. We discuss possible ways to improve the understanding of the predictive skill of GPIs and therefore enhance their applicability in the era of TC‐permitting GCMs.

An approach to link climate model tropical cyclogenesis bias to large-scale wind circulation modes

“…But the EOF analysis is beneficial as it well explains TCG with a more complete picture of large-scale modes. In contrast, local environments, including the genesis potential index, have difficulty in explaining regional TCG in both observations and models (Cavicchia et al, 2023;Menkes et al, 2012).…”

An Approach to Link Climate Model Tropical Cyclogenesis Bias to Large‐Scale Wind Circulation Modes

“…But the EOF analysis is beneficial as it well explains TCG with a more complete picture of large‐scale modes. In contrast, local environments, including the genesis potential index, have difficulty in explaining regional TCG in both observations and models (Cavicchia et al., 2023; Menkes et al., 2012).…”