The Impact of SST Boundary Condition on Tropical Cyclone Track, Intensity, and Structure

The use of coupled atmosphere-ocean models applied for predicting the evolution of tropical cyclone (TC) track, intensity, and structure has increased dramatically in recent years. The contention for the use of dynamical ocean models, within these coupled-models, is to better predict the role which the ocean plays in modulating the aforementioned characteristics of the TC. This study investigates the impact that the sea-surface temperature (SST) boundary-condition has upon TC track, intensity, and structure. Experiments involving static (non-evolving) SST boundary conditions and those which evolve as a function of a both 1-dimensional (no-horizontal advection) and 3-dimensional (fully-coupled) ocean model are evaluated. Conclusions derived from these experiments, for several TC case studies – each within different atmospheric and oceanic environments and with varying traits (ie. translational velocity, synoptic scale interactions, etc.), will provide additional insight into when the use of a static TC boundary condition is suitable versus a temporally evolving SST boundary condition. Further, the instances when a 1-dimensional ocean model sufficiently resolves the observed SST response versus when a fully coupled 3-dimensional ocean model is required will be quantified.