CN102902843B - Method for simulating generating and thawing process of sea ice covered by thin snow - Google Patents

Abstract

The invention discloses a method for simulating the generating and thawing process of sea ice covered by thin snow. The method comprises the steps of: setting the sea ice covered by the thin snow and environmental parameters of the sea ice; calculating parameters such as salinity, heat conductivity, and melting latent heat of the sea ice; calculating the solar shortwave radiation, the atmosphere long wave radiation and various heat fluxes of the sea ice according to the environmental parameters; calculating the temperature at the boundary of a snow layer and an ice surface according to a thermodynamic equation; and judging whether the upper boundary layer of the sea ice is thawed or not, if so, calculating the change rate of the ice thickness of the upper boundary ice layer; calculating the change rate of the thickness of the lower boundary layer of the sea ice according to an internal heat conduction equation; and finally calculating the thickness of the sea ice according to the change rates of the thicknesses of the upper and lower boundary layers of the sea ice. The method has the characteristic of high calculation efficiency and can be used for the simulation on the generating and thawing process of the sea ice covered by thin snow.

Description

A kind of thin snow covers the analogy method of sea ice generating and vanishing process

Technical field

The invention belongs to physical oceangraphy technical field, be specifically related to the analogy method that a kind of thin snow covers sea ice generating and vanishing process.

Background technology

Sea ice refers to the salt water ice directly freezed by seawater, the potpourri be made up of solid ice, bittern and the bubble etc. that contains salt.The drift of sea ice and diffusion motion can cause serious threat to offshore oil platform, Shipping etc.; Meanwhile, sea ice is at marine hydrology, and be also one of important factor in order in the research field such as general circulation and weather, especially thin sea ice plays a key effect in the research of ocean surface heat stream, steam stream and salinity stream.

The means of sea ice monitoring mainly contain the modes such as research station, marine monitoring platform and remote sensing.Marine monitoring platform belongs to on-the-spot and directly measures, and has higher precision; But the restriction of weather, the factor such as artificial can be subject to, have that monitoring range is little, high in cost of production feature.At present, remote sensing method can obtain the coverage condition of large area sea ice, and identifiable design goes out dissimilar sea ice, but still has certain deficiency in inverting sea ice thickness.And the precision improving sea ice thickness inversion algorithm that is modeled as of Sea ice bacteria process provides foundation and reference.

The seawater of the air of sea ice and top, snow deposit and below carries out various forms of material and energy exchange.Research shows, compared with kinetic factor, Thermodynamics has conclusive effect in Sea ice bacteria process, as the various thermofluxs of solar radiation, long _ wave radiation and sea ice self, pyroconductivity, the physicochemical property such as density and temperature of these heat radiations and material are closely related, especially sea ice internal temperature.When covering without snow deposit, whether the temperature solving air and ice face intersection by thermodynamical equilibrium equation decides sea ice top margin layer and melts.And when there being snow deposit to cover, usual employing thermic vibrating screen solves sea ice internal temperature with position and the rate of change of time to simulate Sea ice bacteria process, in order to obtain higher precision, usually layered method is carried out to snow and sea ice, the method efficiency is lower, and need consider the stability of algorithm.

Summary of the invention

Goal of the invention: for the deficiencies in the prior art, the object of this invention is to provide the analogy method that a kind of thin snow covers sea ice generating and vanishing process, meets request for utilization to make it.

Technical scheme: in order to realize foregoing invention object, the technical solution used in the present invention is as follows:

Thin snow covers an analogy method for sea ice generating and vanishing process, comprises following steps:

(1) environmental parameter that the thin snow of t covers sea ice parameter and described sea ice is set;

(2) according to sea ice and environmental parameter, the parameters such as the salinity of sea ice, pyroconductivity and latent heat of fusion are calculated;

(3) according to sea ice and environmental parameter, calculate solar shortwave radiation, penetrate sea ice and do not contribute the heat transfer flux of the shortwave radiation flux of heat, long _ wave radiation, the Sensible Heating Flux of sea ice, the latent heat flux of sea ice and sea ice;

(4) according to thermodynamical equilibrium equation, the temperature T of snow deposit and ice face intersection is calculated ₀, and judge whether sea ice top interlayer melts, if melt, calculate the rate of change λ of sea ice top interlayer ice thickness _up;

(5) according to ice heat conduction equation, the rate of change λ of sea ice boundary layer thickness is calculated _bot, and calculate the thickness of t+ Δ t sea ice .

Wherein, step (1) arranges the thin snow of t and covers sea ice and environmental parameter thereof, is specially:

In t, sea ice parameter has { h _si, ρ _si, T _si, T _f, wherein, h _sifor the thickness of sea ice, ρ _sifor the density of sea ice, T _sifor the temperature of sea ice, T _ffor the freezing point temperature in ice face; Parameter { the ρ of sea ice lower floor seawater _w, C _w, T _w, wherein, ρ _wfor the density of seawater, C _wfor extra large specific heat of water, T _wfor the temperature of seawater; The parameter of snow deposit has { h _s, ρ _s, T _s, α }, wherein, h _sfor the thickness of snow deposit, ρ _sfor the density of snow deposit, T _sfor the temperature of snow deposit, α is the albedo of snow deposit; The parameter of snow deposit upper air and atmosphere radiation thereof has { T _a, u _a, q _a, P ₀, C, ε _lW, e ₀, θ _z, wherein, T _afor the temperature of air, u _afor the wind speed above ice face, q _afor the specific humidity of air, C is cloud amount coefficient, ε _lWfor the emissivity of long wave, e ₀for water vapor pressure in air, P ₀for standard atmospheric pressure, θ _zfor solar zenith angle.

Wherein, step (2), according to sea ice and environmental parameter thereof, calculates the parameters such as the salinity of sea ice, pyroconductivity and latent heat of fusion; Be specially:

Environmentally parameter, calculates the salinity of sea ice $S_{\mathrm{si}}=\left\{\begin{array}{cc}14.24-19.39h_{\mathrm{si}}& h_{\mathrm{si}}\≤0.4\\ 7.88-1.59h_{\mathrm{si}}& h_{\mathrm{si}}>0.4\end{array}\right.$ ，

The pyroconductivity of sea ice $k_{\mathrm{si}}=2.03+\frac{0.117S_{\mathrm{si}}}{T_{\mathrm{si}}-273.0}$ ，

The pyroconductivity of snow $k_s=2.845\×{10}^{-6}{\mathrm{\ρ}}_s^2+2.7\×{10}^{-4}\×2^{\frac{T_s-233}{5}}$ ，

The latent heat of fusion of sea ice $L_{\mathrm{si}}=4.187{\×10}^3(79.68-0.505T_f-0.0273S_{\mathrm{si}}+\frac{4.3115S_{\mathrm{si}}}{T_f}+8\×{10}^{-4}{T}_f{S}_{\mathrm{si}}-0.009T_f^2)$ ，

The density of air ${\mathrm{\ρ}}_a=\frac{349}{T_a}$ ；

Wherein, step (3), according to sea ice and environmental parameter thereof, calculates solar shortwave radiation, penetrates sea ice and does not contribute the Sensible Heating Flux of the shortwave radiation flux of heat, long _ wave radiation, sea ice, latent heat flux and heat transfer flux thereof; Be specially:

According to sea ice and environmental parameter thereof, calculate the thermodynamic flows of following heat radiation and sea ice:

1. solar shortwave radiation $F_{\mathrm{SW}}=\frac{1368(1-0.6C^3){\cos }^2{\mathrm{\θ}}_z}{1.085\cos {\mathrm{\θ}}_z+e_0(2.7+\cos {\mathrm{\θ}}_z){\×10}^{-3}+0.10}$ ；

2. penetrate sea ice and do not contribute the shortwave radiation flux of heat $I_0=\frac{1.7\×\{1-[0.58-4.35({\mathrm{\ρ}}_s-920)\×{10}^{-4}\left]\right\}}{h_s+10}{F}_{\mathrm{SW}}$ ；

3. long _ wave radiation $F_{\mathrm{LW}}=5.670\×{10}^{-8}[(0.746+0.0066e_0)(1+0.26C)T_a^4-{\mathrm{\ϵ}}_{\mathrm{LW}}{T}_0^4]$ , wherein, T ₀for the temperature of snow deposit and ice face intersection, usual ε _lW=0.97;

4. the Sensible Heating Flux F of sea ice _sen=1004.5 (1+0.9433q _a) ρ _ac _senu _a(T _a-T ₀), wherein, C _senfor ice face sensible heat transmission coefficient, it is relevant with the thickness of sea ice; During thin ice, C _senget 0.003; During thick ice, C _senget 0.00175; During medium ice thickness, C _senget 0.0023;

5. the heat transfer flux of sea ice $F_c=\frac{k_{\mathrm{si}}{k}_s}{k_s{h}_{\mathrm{si}}+k_{\mathrm{si}}{h}_s}(T_f-T_0)$ ；

6. the latent heat flux F of sea ice _lat=ρ _au _a(q _a-q ₀) C _latr, wherein, ice face latent heat transmission coefficient $C_{\mathrm{lat}}=\{1-0.146785\exp [-0.292400(u_a-2.206648)]+1.6112292u_a^{-1}\}\&times;{10}^{-3}$ , the specific humidity of snow deposit and ice face intersection $q_0=\left\{\begin{array}{cc}\frac{0.622\left[\exp ((-6763.6/T_0)-4.9283\ln T_0+54.23\right]}{P_0-0.378\left[\exp \right((-6763.6/T_0)-4.9283\ln T_0+54.23]}& T_0\&GreaterEqual;273.15\\ \frac{0.622\left[\exp \right((-6141/T_0)+24.3]}{P_0-0.378[\exp ((-6141/T_0)+24.3]}& T_0<273.15\end{array}\right.$ ，

The heat of sublimation of sea ice $R=\left\{\begin{array}{cc}2.5\&times;{10}^6-2.375{\&times;10}^3(T_0-273.15)& T_0\&GreaterEqual;273.15\\ 2.5{\&times;10}^6-2.375\&times;{10}^3(T_0-273.15)+3.35{\&times;10}^5& T_0<273.15\end{array}\right.$ ；

Wherein, step (4), according to thermodynamical equilibrium equation, calculates the temperature T of snow deposit and ice face intersection ₀, and judge whether sea ice top interlayer melts, if melt, calculate the rate of change λ of sea ice top interlayer ice thickness _up; Be specially:

The thermodynamical equilibrium equation of snow deposit and ice face intersection is: (1-α) F _sW-I ₀+ F _lW(T ₀)+F _sen(T ₀)+F _lat(T ₀)+F _c(T ₀)=0 (a), wherein, T ₀for unknown quantity, dichotomy is adopted to solve, if T ₀< T _f, then the temperature of snow deposit and ice face intersection is still T ₀, and the top interlayer of sea ice does not melt, that is, the rate of change λ of sea ice top interlayer ice thickness _up=0; Otherwise T ₀=T _f, and the coboundary melting layer of sea ice, make the T in formula (a) ₀=T _f, try to achieve sea ice heat of fusion flux F _melt=-{ (1-α) F _sW-I ₀+ F _lW(T _f)+F _sen(T _f)+F _lat(T _f)+F _c(T _f), then ;

Wherein, step (5), according to ice heat conduction equation, calculates the rate of change λ of sea ice boundary layer thickness _bot, and calculate the thickness of t+ Δ t sea ice ; Be specially:

According to ice heat conduction equation, calculate the rate of change of sea ice boundary layer thickness , then in t+ Δ t, sea ice thickness , wherein, Δ t is time step.

Beneficial effect: compared with prior art, contemplated by the invention thin snow and covers the situation of melting in boundary layer on ice of plunging into the commercial sea.On thin snow-sea ice-seawater three layer model basis, empirical model is adopted quantitatively to calculate the important parameter relevant with Thermodynamics such as the salinity of sea ice, pyroconductivity and latent heat of fusion; According to thermodynamical equilibrium equation and ice heat conduction equation, calculate the rate of change of sea ice up-and-down boundary layer ice thickness, thus the process reaching the growth of simulation sea ice thickness and disappear, avoid layered method, therefore there is higher operation efficiency, can be used for the simulation that thin snow covers sea ice generating and vanishing process.

Accompanying drawing explanation

Fig. 1 is process flow diagram of the present invention.

Embodiment

Below in conjunction with specific embodiment, the present invention is described further.

Embodiment 1

As shown in Figure 1, thin snow covers the analogy method of sea ice generating and vanishing process, comprises the following steps:

(1) the thin snow of t is set and covers sea ice and environmental parameter thereof;

In t, sea ice parameter has { h _si, ρ _si, T _si, T _f, wherein, h _sifor the thickness of sea ice, ρ _sifor the density of sea ice, T _sifor the temperature of sea ice, T _ffor the freezing point temperature in ice face; Parameter { the ρ of sea ice lower floor seawater _w, C _w, T _w, wherein, ρ _wfor the density of seawater, C _wfor extra large specific heat of water, T _wfor the temperature of seawater; The parameter of snow deposit has { h _s, ρ _s, T _s, α }, wherein, h _sfor the thickness of snow deposit, ρ _sfor the density of snow deposit, T _sfor the temperature of snow deposit, α is the albedo of snow deposit; The parameter of snow deposit upper air and atmosphere radiation thereof has { T _a, u _a, q _a, P ₀, C, ε _lW, e ₀, θ _z, wherein, T _afor the temperature of air, u _afor the wind speed above ice face, q _afor the specific humidity of air, C is cloud amount coefficient, ε _lWfor the emissivity of long wave, e ₀for water vapor pressure in air, P ₀for standard atmospheric pressure, θ _zfor solar zenith angle.

(2) according to sea ice and environmental parameter thereof, the parameters such as the salinity of sea ice, pyroconductivity and latent heat of fusion are calculated;

Environmentally parameter, calculates the salinity of sea ice $S_{\mathrm{si}}=\left\{\begin{array}{cc}14.24-19.39h_{\mathrm{si}}& h_{\mathrm{si}}\&le;0.4\\ 7.88-1.59h_{\mathrm{si}}& h_{\mathrm{si}}>0.4\end{array}\right.$ ，

The pyroconductivity of sea ice $k_{\mathrm{si}}=2.03+\frac{0.117S_{\mathrm{si}}}{T_{\mathrm{si}}-273.0}$ ，

The pyroconductivity of snow $k_s=2.845\&times;{10}^{-6}{\mathrm{\&rho;}}_s^2+2.7\&times;{10}^{-4}\&times;2^{\frac{T_s-233}{5}}$ ，

The latent heat of fusion of sea ice $L_{\mathrm{si}}=4.187{\&times;10}^3(79.68-0.505T_f-0.0273S_{\mathrm{si}}+\frac{4.3115S_{\mathrm{si}}}{T_f}+8\&times;{10}^{-4}{T}_f{S}_{\mathrm{si}}-0.009T_f^2)$ ，

The density of air ${\mathrm{\&rho;}}_a=\frac{349}{T_a}$ 。

(3) according to sea ice and environmental parameter thereof, calculate solar shortwave radiation, penetrate sea ice and do not contribute the Sensible Heating Flux of the shortwave radiation flux of heat, long _ wave radiation, sea ice, latent heat flux and heat transfer flux thereof;

According to sea ice and environmental parameter thereof, calculate the thermodynamic flows of following heat radiation and sea ice:

1. solar shortwave radiation $F_{\mathrm{SW}}=\frac{1368(1-0.6C^3){\cos }^2{\mathrm{\&theta;}}_z}{1.085\cos {\mathrm{\&theta;}}_z+e_0(2.7+\cos {\mathrm{\&theta;}}_z){\&times;10}^{-3}+0.10}$ ；

2. penetrate sea ice and do not contribute the shortwave radiation flux of heat $I_0=\frac{1.7\&times;\{1-[0.58-4.35({\mathrm{\&rho;}}_s-920)\&times;{10}^{-4}\left]\right\}}{h_s+10}{F}_{\mathrm{SW}}$ ；

3. long _ wave radiation $F_{\mathrm{LW}}=5.670\&times;{10}^{-8}[(0.746+0.0066e_0)(1+0.26C)T_a^4-{\mathrm{\&epsiv;}}_{\mathrm{LW}}{T}_0^4]$ , wherein, T ₀for the temperature of snow deposit and ice face intersection, usual ε _lW=0.97;

4. the Sensible Heating Flux F of sea ice _sen=1004.5 (1+0.9433q _a) ρ _ac _senu _a(T _a-T ₀), wherein, C _senfor ice face sensible heat transmission coefficient, it is relevant with the thickness of sea ice; During thin ice, C _senget 0.003; During thick ice, C _senget 0.00175; During medium ice thickness, C _senget 0.0023;

5. the heat transfer flux of sea ice $F_c=\frac{k_{\mathrm{si}}{k}_s}{k_s{h}_{\mathrm{si}}+k_{\mathrm{si}}{h}_s}(T_f-T_0)$ ；

6. the latent heat flux F of sea ice _lat=ρ _au _a(q _a-q ₀) C _latr, wherein, ice face latent heat transmission coefficient $C_{\mathrm{lat}}=\{1-0.146785\exp [-0.292400(u_a-2.206648)]+1.6112292u_a^{-1}\}\&times;{10}^{-3}$ ，

The specific humidity of snow deposit and ice face intersection $q_0=\left\{\begin{array}{cc}\frac{0.622\left[\exp ((-6763.6/T_0)-4.9283\ln T_0+54.23\right]}{P_0-0.378\left[\exp \right((-6763.6/T_0)-4.9283\ln T_0+54.23]}& T_0\&GreaterEqual;273.15\\ \frac{0.622\left[\exp \right((-6141/T_0)+24.3]}{P_0-0.378[\exp ((-6141/T_0)+24.3]}& T_0<273.15\end{array}\right.$ ，

The heat of sublimation of sea ice $R=\left\{\begin{array}{cc}2.5\&times;{10}^6-2.375{\&times;10}^3(T_0-273.15)& T_0\&GreaterEqual;273.15\\ 2.5{\&times;10}^6-2.375\&times;{10}^3(T_0-273.15)+3.35{\&times;10}^5& T_0<273.15\end{array}\right.$ 。

(4) according to thermodynamical equilibrium equation, the temperature T of snow deposit and ice face intersection is calculated ₀, and judge whether sea ice top interlayer melts, if melt, calculate the rate of change λ of sea ice top interlayer ice thickness _up; The thermodynamical equilibrium equation of snow deposit and ice face intersection is (1-α) F _sW-I ₀+ F _lW(T ₀)+F _sen(T ₀)+F _lat(T ₀)+F _c(T ₀)=0 (a), wherein, T ₀for unknown quantity, dichotomy is adopted to solve, if T ₀< T _f, then the temperature of snow deposit and ice face intersection is still T ₀, and the top interlayer of sea ice does not melt, that is, the rate of change λ of sea ice top interlayer ice thickness _up=0; Otherwise T ₀=T _f, and the coboundary melting layer of sea ice, make the T in formula (a) ₀=T _f, try to achieve sea ice heat of fusion flux F _melt=-{ (1-α) F _sW-I ₀+ F _lW(T _f)+F _sen(T _f)+F _lat(T _f)+F _c(T _f), then .

(5) according to ice heat conduction equation, the rate of change λ of sea ice boundary layer thickness is calculated _bot, and calculate the thickness of t+ Δ t sea ice ;

According to ice heat conduction equation, calculate the rate of change of sea ice boundary layer thickness , then in t+ Δ t, sea ice thickness , wherein, Δ t is time step.

Embodiment 2

(1) the thin snow of t is set and covers sea ice and environmental parameter thereof;

In t, sea ice parameter has { h _is, ρ _si, T _si, T _f, wherein, sea ice thickness h _is=1.0m, sea ice density p _si=910kg/m ³, sea ice temperature T _si=272K, the freezing point temperature T in ice face _f=271.2K.

Parameter { the ρ of sea ice lower floor seawater _w, C _w, T _w, wherein, density of sea water ρ _w=1025kg/m ³, seawater specific heat C _w=4096J/ (kgK), ocean temperature T _w=272.5K.

The parameter of snow deposit has { h _s, ρ _s, T _s, α }, wherein, snow thicknes h _s=0.015m, snow deposit density p _s=320kg/m ³, snow deposit temperature T _s=268K, snow deposit albedo α=0.8.

The parameter of snow deposit upper air and atmosphere radiation thereof has { T _a, u _a, q _a, P ₀, C, ε _lW, e ₀, θ _z, wherein, air themperature T _a=268K, the wind speed u above ice face _a=7.3m/s, air specific humidity q _a=2.5 × 10 ^-3, cloud amount coefficient C=0.7, longwave transmissions rate ε _lW=0.97, water vapor pressure e in air ₀=4.0hPa, standard atmospheric pressure P ₀=1013hPa, solar zenith angle θ _z=65 °.

(2) according to sea ice and environmental parameter thereof, the parameters such as the salinity of sea ice, pyroconductivity and latent heat of fusion are calculated;

Environmentally parameter, calculates the salinity of sea ice $S_{\mathrm{si}}=\left\{\begin{array}{cc}14.24-19.39h_{\mathrm{si}}& h_{\mathrm{si}}\&le;0.4\\ 7.88-1.59h_{\mathrm{si}}& h_{\mathrm{si}}>0.4\end{array}\right.$ , obtain salinity of sea ice S _si=6.29ppt.

Calculate the pyroconductivity of sea ice , obtain sea ice pyroconductivity k _si=2.03W/ (mK).

Calculate the pyroconductivity of snow $k_s=2.845\&times;{10}^{-6}{\mathrm{\&rho;}}_s^2+2.7\&times;{10}^{-4}\&times;2^{\frac{T_s-233}{5}}$ , obtain the pyroconductivity k avenged _s=0.33W/ (mK)

Calculate the latent heat of fusion of sea ice $L_{\mathrm{si}}=4.187{\&times;10}^3(79.68-0.505T_f-0.0273S_{\mathrm{si}}+\frac{4.3115S_{\mathrm{si}}}{T_f}+8\&times;{10}^{-4}{T}_f{S}_{\mathrm{si}}-0.009T_f^2)$ , obtain the latent heat of fusion L of sea ice _si=2.73 × 10 ⁵j/kg.

Calculate the density of air , obtain the density p of air _a=1.30kg/m ³.

According to step (3) and (4) of embodiment 1, adopt dichotomy calculating formula (a), obtain T ₀=269.4, show that the upper surface of sea ice can melt, calculate F _melt=3.46 × 10 ^-13w/ m ², the rate of change λ of sea ice top interlayer ice thickness _up=-1.39 × 10 ^-21m/s.

According to the step (5) of embodiment 1, obtain the rate of change λ of sea ice boundary layer ice thickness _bot=-2.45 × 10 ^-7m/s, if make time step Δ t=24 × 3600s, namely through the time of one day, the thickness of sea ice is , namely dissolved 2.1cm.

Claims (3)

1. thin snow covers an analogy method for sea ice generating and vanishing process, it is characterized in that, comprises following steps:

(1) environmental parameter that the thin snow of t covers sea ice parameter and described sea ice is set;

(2) according to sea ice and environmental parameter, the salinity of sea ice, pyroconductivity and latent heat of fusion is calculated;

(3) according to sea ice and environmental parameter, calculate solar shortwave radiation, penetrate sea ice and do not contribute the heat transfer flux of the shortwave radiation flux of heat, long _ wave radiation, the Sensible Heating Flux of sea ice, the latent heat flux of sea ice and sea ice;

(4) according to thermodynamical equilibrium equation, the temperature T of snow deposit and ice face intersection is calculated ₀, and judge whether sea ice top interlayer melts, if melt, calculate the rate of change λ of sea ice top interlayer ice thickness _up;

(5) according to ice heat conduction equation, the rate of change λ of sea ice boundary layer thickness is calculated _bot, and calculate the thickness of t+ Δ t sea ice

In step (1), the environmental parameter of sea ice parameter and sea ice is specially: sea ice parameter has { h _si, ρ _si, T _si, T _f, wherein, h _sifor the thickness of sea ice, ρ _sifor the density of sea ice, T _sifor the temperature of sea ice, T _ffor the freezing point temperature in ice face; Parameter { the ρ of sea ice lower floor seawater _w, C _w, T _w, wherein, ρ _wfor the density of seawater, C _wfor extra large specific heat of water, T _wfor the temperature of seawater; The parameter of snow deposit has { h _s, ρ _s, T _s, α }, wherein, h _sfor the thickness of snow deposit, ρ _sfor the density of snow deposit, T _sfor the temperature of snow deposit, α is the albedo of snow deposit; The parameter of snow deposit upper air and atmosphere radiation thereof has { T _a, u _a, q _a, P ₀, C, ε _lW, e ₀, θ _z, wherein, T _afor the temperature of air, u _afor the wind speed above ice face, q _afor the specific humidity of air, C is cloud amount coefficient, ε _lWfor the emissivity of long wave, e ₀for water vapor pressure in air, P ₀for standard atmospheric pressure, θ _zfor solar zenith angle;

In step (2), detailed process is:

Environmentally parameter, calculates the salinity of sea ice $S_{\mathrm{si}}=\left\{\begin{array}{cc}14.24-19.39h_{\mathrm{si}}& h_{\mathrm{si}}\&le;0.4\\ 7.88-1.59h_{\mathrm{si}}& h_{\mathrm{si}}>0.4\end{array}\right.,$ The pyroconductivity of sea ice $k_{\mathrm{si}}=2.03+\frac{0.117S_{\mathrm{si}}}{T_{\mathrm{si}}-273.0},$ The pyroconductivity of snow $k_s=2.845\&times;{10}^{-6}{\mathrm{\&rho;}}_s^2+2.7\&times;{10}^{-4}\&times;2^{\frac{T_s-233}{5}},$ The latent heat of fusion of sea ice $L_{\mathrm{si}}=4.187\&times;{10}^3(79.68-{0.505T}_f-0.0273S_{\mathrm{si}}+\frac{4.3115S_{\mathrm{si}}}{T_f}+8\&times;{10}^{-4}{T}_f{S}_{\mathrm{si}}-{0.009T}_f^2),$ The density of air ${\mathrm{\&rho;}}_a=\frac{349}{T_a};$

In step (3), detailed process is: according to sea ice and environmental parameter thereof, calculates the thermodynamic flows of following heat radiation and sea ice: 1. solar shortwave radiation $F_{\mathrm{SW}}=\frac{1368(1-0.6C^3){\cos }^2{\mathrm{\&theta;}}_z}{1.085\cos {\mathrm{\&theta;}}_z+e_0(2.7+\cos {\mathrm{\&theta;}}_z)\&times;{10}^{-3}+0.10};$ 2. penetrate sea ice and do not contribute the shortwave radiation flux of heat $I_0=\frac{1.7\&times;\{1-[0.58-4.35({\mathrm{\&rho;}}_s-920)\&times;{10}^{-4}\left]\right\}}{h_s+10}{F}_{\mathrm{SW}};$ 3. long _ wave radiation wherein, T ₀for the temperature of snow deposit and ice face intersection; 4. the Sensible Heating Flux F of sea ice _sen=1004.5 (1+0.9433q _a) ρ _ac _senu _a(T _a-T ₀), wherein, C _senfor ice face sensible heat transmission coefficient; 5. the heat transfer flux of sea ice 6. the latent heat flux F of sea ice _lat=ρ _au _a(q _a-q ₀) C _latr, wherein, C _latfor ice face latent heat transmission coefficient, q ₀for the specific humidity of snow deposit and ice face intersection, R is the heat of sublimation of sea ice.

2. thin snow according to claim 1 covers the analogy method of sea ice generating and vanishing process, and it is characterized in that, in step (4), detailed process is: the thermodynamical equilibrium equation of snow deposit and ice face intersection is (1-α) F _sW-I ₀+ F _lW(T ₀)+F _sen(T ₀)+F _lat(T ₀)+F _c(T ₀)=0 (a), wherein, T ₀for unknown quantity, dichotomy is adopted to solve, if T ₀<T _f, then the temperature of snow deposit and ice face intersection is still T ₀, and the top interlayer of sea ice does not melt, that is, the rate of change λ of sea ice top interlayer ice thickness _up=0; Otherwise T ₀=T _f, and the coboundary melting layer of sea ice, make the T in formula (a) ₀=T _f, try to achieve sea ice heat of fusion flux F _melt=-{ (1-α) F _sW-I ₀+ F _lW(T _f)+F _sen(T _f)+F _lat(T _f)+F _c(T _f), then

3. thin snow according to claim 1 covers the analogy method of sea ice generating and vanishing process, and it is characterized in that, in step (5), detailed process is: according to ice heat conduction equation, calculates the rate of change of sea ice boundary layer thickness ${\mathrm{\&lambda;}}_{\mathrm{bot}}=\frac{F_c-[1.16\&times;{10}^{-5}{\mathrm{\&rho;}}_w{C}_w(T_w-T_f)]}{{\mathrm{\&rho;}}_{\mathrm{si}}{L}_{\mathrm{si}}},$ Then in t+ Δ t, sea ice thickness ${\tilde{h}}_{\mathrm{si}}=h_{\mathrm{si}}+({\mathrm{\&lambda;}}_{\mathrm{up}}+{\mathrm{\&lambda;}}_{\mathrm{bot}})\mathrm{\&Delta;t},$ Wherein, Δ t is time step.