An Analysis of the Observed Low-level Structure of Rapidly Intensifying and Mature Hurricane Earl (2010)

摘要: Abstract : We examine dynamic and thermodynamic aspects of Atlantic hurricane Earl (2010) during its intensification mature phases over four days intensive measurements. During this period, underwent an episode rapid intensification, maturity, secondary eyewall replacement, re-intensification the early part decline. The observations are used to appraise elements a new model for tropical-cyclone intensification. results affirm conventional (vortex interior) boundary-layer spin-up mechanisms that form dynamical azimuthally averaged view model. average maximum tangential winds beneath found exceed gradient wind by between 20 60%. suggest also balance approximation in low-level vortex interior above strong inflow layer may not be as accurate inner-core region tropical cyclone has been widely held. An analysis structure affirms radial increase moist equivalent potential temperature, e ,with decreasing radius process,a necessary ingredient maintaining convective instability presence warming upper troposphere. unanticipated finding is discovery unmixed boundary terms within several hundred kilometres centre. In region, consistent with axisymmetric eruption into unless there non-conservative (eddy) processes acting modify entropy ascending air.