资源环境科技发展态势分析平台

Several previous studies have demonstrated the significant sensitivity of simulated tropical cyclone structure and intensity to variations in surface-exchange coefficients for enthalpy (C_k) and momentum (C_d), respectively. In this study we investigate the consistency of the estimated peak intensity, intensification rate, and steady-state structure between an analytical model and idealized axisymmetric numerical simulations for both constant C_k and C_d values and various wind speed–dependent representations of C_k and C_d. The present analysis with constant C_k and C_d values demonstrates that the maximum wind speed is similar for identical C_k/C_d values less than 1, regardless of whether changes were made to C_k or C_d. However, for a given C_k/C_d greater than 1, the simulated and theoretical maximum wind speed are both greater if C_d is decreased compared to C_k increased. This behavior results because of a smaller enthalpy disequilibrium at the radius of maximum winds for larger C_k. Additionally, the intensification rate is shown to increase with C_k and C_d and the steady-state normalized wind speed beyond the radius of maximum winds is shown to increase with increasing C_d. Experiments with wind speed–dependent C_k and C_d were found to be generally consistent, in terms of the intensification rate and the simulated and analytical-model-estimated maximum wind speed, with the experiments with constant C_k and C_d.