Stratified
coastal ocean interactions with tropical cyclones
Scott Glenn, Travis Miles, Greg Seroka
Rutgers University
Noon Mar 22 in Room 2155
Abstract:
Hurricane intensity forecast improvements currently lag the progress
achieved for hurricane tracks. Integrated ocean observations and
simulations during Hurricane Irene (2011) reveal that the wind-forced
two-layer circulation of the stratified coastal ocean, and resultant
shear-induced mixing, led to significant and rapid ahead-of-eye-centre
cooling (at least 6 °C and up to 11 °C) over a wide swath of the
Mid-Atlantic Bight continental shelf. Atmospheric simulations establish
this cooling as the missing contribution required to reproduce Irene’s
accelerated intensity reduction. Historical buoys from 1985 to 2015
show that ahead-of-eye-centre cooling occurred beneath all 11 tropical
cyclones that traversed the Mid-Atlantic Bight continental shelf during
stratified summer conditions. A Yellow Sea buoy similarly revealed
significant and rapid ahead-of-eye-centre cooling during Typhoon Muifa
(2011). These findings establish that including realistic coastal
baroclinic processes in forecasts of storm intensity and impacts will
be increasingly critical to mid-latitude population centres as sea
levels rise and tropical cyclone maximum intensities migrate poleward.
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