Sensitivity to planetary boundary layer parameterizations in realistic hurricane simulations

Historically, it has been recognized that it is in the hurricane boundary layer where most of the frictional dissipation occurs and that boundary layer friction induces inflow that converges humidity. However, it has been only recently demonstrated that boundary layer dynamics play a fundamental role in hurricane intensification through the convergence of absolute angular momentum. This recent realization has been supported by theory, idealized numerical simulations and observations.

Despite their acknowledged relevance, the dynamics of the hurricane boundary layer are not yet well understood. Most of the theory of the atmospheric boundary layer, as well as the boundary layer parameterizations in full physics models have not been developed considering the hurricane environment and substantial disagreement on the essential characteristics of the hurricane boundary layer prevail. Despite the disagreements in the community, idealized numerical integrations have shown that regardless of the planetary boundary layer parameterization chosen, convergence of absolute angular momentum in the boundary layer is a robust feature and that such convergence is important in the intensification of tropical cyclones. In this work, we present a set of WRF full-physics, realistic Eastern Pacific hurricane simulations to explore the hurricane sensitivity to boundary layer parameterizations.