Analysis of Ability of HighResMIP Models to Simulate ENSO-TC Relationship

El Niño Southern Oscillation (ENSO) modulates tropical cyclone (TC) activity in different regions as ENSO causes changes in vertical wind shear, humidity, and subtropical highs, all of which impact TC activity. In this study, we examined how well the High-Resolution Model Intercomparison Project (HighResMIP) models are able to reproduce the observed ENSO-TC relationship and examine if and how they will change in the future. We use historical observational data from NOAA (for ENSO) and the International Best Track Archive for Climate Stewardship (IBTrACS; for TCs) to compare with the HighResMIP models. The ability of the models to simulate the ENSO-TC relationship is examined using several diagnostics. The main diagnostic examined is the track density difference between El Niño and La Niña. Several of the models were unable to reproduce the ENSO-TC track density difference relationship in the North Atlantic and Northeast Pacific basins, which have a strong modulation by ENSO in observations. Additional diagnostics include genesis and ACE density, storm lifetime, and annual cycle per basin and how they differ by ENSO phase. These various diagnostics allow us to investigate which aspects of the ENSO-TC relationship each model is able to simulate and determine if there are systematic model biases between the coupled and uncoupled models. Furthermore, the models’ large-scale environmental fields will be used to interpret model differences for both historical and future simulations. We will compare the HighResMIP future simulations (2015-2050) with the historical simulations to investigate if and how the ENSO-TC relationship may change due to anthropogenic climate change across different models and examine their statistical significance and robustness.