Why Do the Maximum Intensities in Modeled Tropical Cyclones Vary Under the Same Environmental Conditions?

Abstract In this study w e explored why the different initial tropical cyclone structures can result in different steady‐state maximum intensities in model simulations with the same environmental conditions. We discovered a linear relationsh ip between the radius of maximum wind ( r m ) and the absolute angular momentum that passes through r m ( M m ) in the model simulated steady‐state tropical cyclones that r m  =  aM m + b . This nonnegligible intercept b is found to be the key to making a steady‐state storm with a larger M m more intense. The sensitivity experiments show that this nonzero b results mainly from horizontal turbulent mixing and decreases with decreased horizontal mixing. Using this linear relationship from the simulations, it is also found that the degree of supergradient wind is a function of M m as well as the turbulent mixing length such that both a larger M m and/or a reduced turbulent mixing length result in larger supergradient winds.