Morris, A., Bender and Isaac Ginis, 2000 : Real-case simulations of
hurricane-ocean interaction using a high-resolution coupled model:
Effects on hurricane intensity. Mon. Wea. Rev., 128, 917-946
In order to study the effect of tropical cyclone-ocean
interaction on the intensity of observed hurricanes.
The GFDL movable triply nested mesh hurricane model
was coupled with a high-resolution version of the
Princeton Ocean Model (POM, Blumberg and Mellor,
The ocean model had 1/6° uniform resolution, which
matched the horizontal resolution of the hurricane model
in its innermost grid .
The grid system for each of the triply nested meshes in
the present study is summarized in Table 1.
The outmost domain is stationary and ranged from 10oS
The two inner meshes are movable and follow the storm
The POM is a three-dimensional, primitive equation
model with complete thermohaline dynamics.
It has an ocean-bottom-following, sigma vertical
coordinate system and a free surface.
The no. of vertical
layers was set 21
and 23 which
enabled the upper
ocean dynamics to
be represented with
The wind stress, heat, moisture, and radiative fluxes
computed in the tropical cyclone model were passed into
the ocean model.
The ocean model was then integrated one step and a
new SST was calculated.
The new SST was used in the ensuing time steps of the
tropical cyclone model.
currents in the
are shown in
by the model
Fig. 4 shows the comparison of the simulated SST and
objectively analyzed observed fields from Shay et al.
(1998) along the section AB in Fig. 3.
Time series of minimum sea level pressure for the
operational forecast (solid line) and coupled experiment
(dotted-dashed line) compared to observed values (thin
The 72-h storm
tracks (thin line) for
two forecast of
Hurricane Opal made
by the coupled
model starting at
different initial time.
starting at 0000
UTC 2 Oct.
cooling of 4.5o-
In the experiments with both the coupling and the initial
cold wake included, the storm’s intensity was much
better reproduced compared to the operational forecast.
Fig. 9 indicates the
dramatic effect the
cold wake had on
period up to landfall.
The ratio for experiments was in fairly good agreement
with the estimates of Emanuel (1986).
This suggest that the relationship obtained in these
experiments between the storm intensity and the
changes in the SST from the ocean-atmospheric
interaction were reasonable.
case of Hurricane
Felix in the western
Cross section along 31.75oN
The experimental case of Hurricane Fran in the western
The SST distribution at 72-h for the two coupled
experiments for Hurricane Fran run with and without
Cross section of SSTs
along 31oN and 32oN
from 3-day composite
AVHRR satellite images
and ocean model-
predicted SSTs at the
beginning of the coupled
1995-98 hurricane seasons
The effect of ocean coupling is one of the important
mechanisms that govern the intensity of tropical
With inclusion of both the cold wake and the ocean
coupling the intensity predictions is much improved.