Journal Article

Real World and Tropical Cyclone World. Part II

Wales, S., Utembe, S., Vaughan, A., Sharmila, S., Walsh, K. J. E., Thatcher, M.

2020

Overview

This study aims to investigate the response of simulated tropical cyclone formation to specific climate conditions, using an idealized aquaplanet framework of an ∼40-km-horizontal-resolution atmospheric general circulation model. Two sets of idealized model experiments have been performed, one with a set of uniformly distributed constant global sea surface temperatures (SSTs) and another in which varying meridional SST gradients are imposed. The results show that the strongest relationship between climate and tropical cyclone formation is with vertical static stability: increased static stability is strongly associated with decreased tropical cyclone formation. Vertical wind shear and midtropospheric vertical velocity also appear to be related to tropical cyclone formation, although below a threshold value of wind shear there appears to be little relationship. The relationship of tropical cyclone formation with maximum potential intensity and mean sea surface temperature is weak and not monotonic. These simulations strongly suggest that vertical static stability should be part of any climate theory of tropical cyclone formation.

• Publisher: American Meteorological Society
• Subject: Atmospheric boundary layer / Atmospheric circulation / Atmospheric circulation models / Climate / Climate change / Climatic conditions / Computer simulation / Cyclones / Experiments / General circulation models / Global temperatures / Gravitational waves / Hurricanes / Sea surface / Sea surface temperature / Simulation / Static stability / Surface temperature / Tropical climate / Tropical climates / Tropical cyclone formation / Tropical cyclone intensities / Tropical cyclones / Vertical stability / Vertical velocities / Vertical wind shear / Vertical wind velocities / Wind / Wind shear