Modeling Interaction of a Tropical Cyclone with Its Cold Wake

Abstract

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Modulating Effects of Mesoscale Oceanic Eddies on Sea Surface Temperature Response to Tropical Cyclones Over the Western North Pacific

“…But the recovering characteristics of SST cooling are still not well understood when ocean eddies are present. Since the spatial shape of SST cooling is influential for the TC intensification (Chen et al, ), it is also important to understand the effect of mesoscale oceanic eddies on the spatial characteristics of SST response to TCs. The contributions of CCEs and WCEs should be different given their intrinsically different properties.…”

The Influences of Orography and Ocean on Track of Typhoon Megi (2016) Past Taiwan as Identified by HWRF

“…The improvement on simulated TC intensity due to ocean coupling has been well elucidated (e.g., Bender & Ginis, ; Davis et al, ; Yablonsky et al, ), in particular, for Megi (2010) over the Western North Pacific (WNP; e.g., Wu et al, ). TC‐induced upper ocean cooling can affect the TC structure and associated marine boundary layer (Lee & Chen, , ; Wu et al, ), which tends to delay a decrease in the TC intensification via enhanced inward moist air transport that offsets the effect of decreasing upward enthalpy fluxes in the boundary layer (Chen et al, ). The intensity simulations of TCs can be improved by reducing the coupling interval between atmosphere and ocean components in fully coupled general circulation models (Scoccimarro et al, ).…”

The influences of ocean on intensity of Typhoon Soudelor (2015) as revealed by coupled modeling

“…For both experiments, larger near‐surface inflow angles are produced to the right of the moving typhoon center. The typhoon‐induced cold wake in the coupled experiment CH tends to produce larger low‐level inflow angles to increase the storm efficiency at the rear‐right quadrant compared with those in UH (Figure d,f), in agreement with previous studies (e.g., Lee and Chen, ; Wu et al ., ; Chen et al ., ). The inflow angles near the surface at the rear‐right quadrant in the coupled experiment can be as large as 25°, which are considerably larger than those presented in Lee and Chen ().…”

“…TC‐induced ocean cooling may change the lower atmosphere by both dynamic and thermodynamic processes (e.g., Lee and Chen, ; ; Chen et al ., ). Sea surface temperature (SST) cooling caused by a TC‐induced cold wake tends to produce a stable boundary layer over the cold wake, and the air parcels at this region will stay for a longer time near the surface, which is found to enhance the transport of energetic air into the inner band of the TC.…”

“…(Lee and Chen, ). Stronger inflow at lower layers over the cold wake due to the enhanced pressure gradient brings moister air to the inner core of the TC as identified by idealized simulations (Chen et al ., ). These cooling‐induced atmospheric processes at lower levels may increase the storm efficiency and somewhat offset the thermodynamic effects of decreased enthalpy fluxes due to SST cooling (Lee and Chen, ; Chen et al ., ).…”