The atmospheric forcing for the JES application of the POM includes mechanical
and thermohaline forcing. The wind forcing is depicted by
where (u,v) and (
) are the two components of the water
velocity and wind stress vectors, respectively. The wind stress at each time
step is interpolated from monthly mean climate wind stress from COADS
(1945-1989). We interpolated the COADS wind stress of the resolution of
1
1
onto the model grid of the resolution of
10
.
Surface thermal forcing is depicted by
where 
and 
are the observed potential temperature and
salinity, 
is the specific heat, 
is the net surface heat flux
(downward positive), P is the precipitation rate, and E is evaporation
rate. The relaxation coefficient C is the reciprocal of the restoring time
period for a unit volume of water. The parameters (
, 
)
are (0,1)-type switches: 
would specify only
flux forcing is applied; 
would specify that
only restoring type forcing is applied.
Chu (1989) pointed out the importance of using compatible surface wind and
thermal boundary conditions. Chu et al. (1998c) further found that the
restoring surface boundary condition does not exist anywhere in the world
ocean. Therefore, in this study, the surface thermohaline forcing is
determined solely by the flux forcing, that is, 
in (3)-(4). The mixing coefficients 
and 
were
computed using a level two-turbulence closure scheme (Mellor and Yamada, 1982).