Paper Review

One-Dimensional Sea One-Dimensional Sea Ice-Ocean Model Ice-Ocean Model Applied to SHEBA Applied to SHEBA

Experiment in 1997-Experiment in 1997-1998 Winter1998 Winter

Wen-Yih Sun and Jiun-Dar ChernWen-Ien

IntroductionIntroduction

• SHEBA: The Surface Heat Budget of the Arctic Ocean

• The model includes 1. a mixed-layer ocean model, ( used to predict water temp., salinity, density, and turbulent kinetic energy )

2. a multi-layer snow/ice model, ( used to predict the thickness, temp., and heat transfer of snow/sea ice )

and the interfaces among atmosphere, snow/sea ice, and sea water.

1. One-Dim. Mixed-Layer Ocean 1. One-Dim. Mixed-Layer Ocean ModelModel

a.a.

zTTHcHt

zTobsfmww

)(/

Sz t

w' S' (Sobs S)z

w 0 1.0 Tc S

bb..

cc..

(Salinity)

(Density)

(Energy)

The equations for a one-dimensional ocean model, which include 27 layers.S: salinity, Δz: layer-thickness, ρ:density, T: water temperature, c: the specific heat capacity.

1. Here k-1/2 and k+1/2 stand for the value at the

top and bottom of the k- layer.

2. is the eddy flux and is derived from .

: the eddy coefficient 3. : the Newtonian forcing for salinity.

a.a. Sanity ( Sanity ( ) )

1/2k1kk)( 2/

Sz t

w' S' (Sobs S)z

S w )(''z

SSw T

T

zSSobs )(

1. : the density of sea water, = 1000 and

= 273.15 K.

2.

b.b. Density ( Density ( ) )

w 0 1.0 Tc S

w 0

1. is the specific heat capacity of sea water.

2 . : the Newtonian forcing for temperature. 3. : the net latent heat released from freezing or

melting.

: is the mass loss (gain) due to freeze (melt) at the

open water surface or ice-water interface. are precipitation rate for rain and snow. is the new fallen snow density.4. The freezing point of seawater: .

c.c. Energy ( Energy ( ) )

zTTHcHt

zTobsfmww

)(/

zTTobs )(

(wz)t

{w Prnew snowPs Eevap}surface M f m

Tsw( fre ) 273.15 55S

5. H is the heat flux inside the seawater.

c.c. Energy Energy

2/3kfor , ''

1/2kfor ,)1(

www

w

RsTwc

RRRsHpHHsH

Sensible Heat Flux

LatentHeat Flux

Heat Transfer of Precipitation albedo

Downward Shortwave Radiation

Upward and Downward Longwave Radiations Eddy Heat Flux

:wind speed near surface;

c.c. EnergyEnergy

Hscaawa' a

' caau** acach Va (sfc a )

H Lvawa' qa

' Lvau*q* LvEevap Lvach Va (qsfc qa )

HpcwwTaPr, for Ta 273.15 K

csnnew snowTaPs, for Ta 273.15 K

To Be Continued…