New URL for NEMO forge!   http://forge.nemo-ocean.eu

Since March 2022 along with NEMO 4.2 release, the code development moved to a self-hosted GitLab.
This present forge is now archived and remained online for history.
Changeset 11544 for NEMO/trunk/doc/latex/NEMO/subfiles/chap_DIU.tex – NEMO

Ignore:
Timestamp:
2019-09-13T16:37:38+02:00 (5 years ago)
Author:
nicolasmartin
Message:

Missing modifications from previous commit

File:
1 edited

Legend:

Unmodified
Added
Removed
  • NEMO/trunk/doc/latex/NEMO/subfiles/chap_DIU.tex

    r11435 r11544  
    5757%=============================================================== 
    5858\section{Warm layer model} 
    59 \label{sec:warm_layer_sec} 
     59\label{sec:DIU_warm_layer_sec} 
    6060%=============================================================== 
    6161 
     
    6565\frac{\partial{\Delta T_{\mathrm{wl}}}}{\partial{t}}&=&\frac{Q(\nu+1)}{D_T\rho_w c_p 
    6666\nu}-\frac{(\nu+1)ku^*_{w}f(L_a)\Delta T}{D_T\Phi\!\left(\frac{D_T}{L}\right)} \mbox{,} 
    67 \label{eq:ecmwf1} \\ 
    68 L&=&\frac{\rho_w c_p u^{*^3}_{w}}{\kappa g \alpha_w Q }\mbox{,}\label{eq:ecmwf2} 
     67\label{eq:DIU_ecmwf1} \\ 
     68L&=&\frac{\rho_w c_p u^{*^3}_{w}}{\kappa g \alpha_w Q }\mbox{,}\label{eq:DIU_ecmwf2} 
    6969\end{align} 
    7070where $\Delta T_{\mathrm{wl}}$ is the temperature difference between the top of the warm layer and the depth $D_T=3$\,m at which there is assumed to be no diurnal signal. 
    71 In equation (\autoref{eq:ecmwf1}) $\alpha_w=2\times10^{-4}$ is the thermal expansion coefficient of water, 
     71In equation (\autoref{eq:DIU_ecmwf1}) $\alpha_w=2\times10^{-4}$ is the thermal expansion coefficient of water, 
    7272$\kappa=0.4$ is von K\'{a}rm\'{a}n's constant, $c_p$ is the heat capacity at constant pressure of sea water, 
    7373$\rho_w$ is the water density, and $L$ is the Monin-Obukhov length. 
     
    7979the relationship $u^*_{w} = u_{10}\sqrt{\frac{C_d\rho_a}{\rho_w}}$, where $C_d$ is the drag coefficient, 
    8080and $\rho_a$ is the density of air. 
    81 The symbol $Q$ in equation (\autoref{eq:ecmwf1}) is the instantaneous total thermal energy flux into 
     81The symbol $Q$ in equation (\autoref{eq:DIU_ecmwf1}) is the instantaneous total thermal energy flux into 
    8282the diurnal layer, \ie 
    8383\[ 
    8484  Q = Q_{\mathrm{sol}} + Q_{\mathrm{lw}} + Q_{\mathrm{h}}\mbox{,} 
    85   % \label{eq:e_flux_eqn} 
     85  % \label{eq:DIU_e_flux_eqn} 
    8686\] 
    8787where $Q_{\mathrm{h}}$ is the sensible and latent heat flux, $Q_{\mathrm{lw}}$ is the long wave flux, 
    8888and $Q_{\mathrm{sol}}$ is the solar flux absorbed within the diurnal warm layer. 
    8989For $Q_{\mathrm{sol}}$ the 9 term representation of \citet{gentemann.minnett.ea_JGR09} is used. 
    90 In equation \autoref{eq:ecmwf1} the function $f(L_a)=\max(1,L_a^{\frac{2}{3}})$, 
     90In equation \autoref{eq:DIU_ecmwf1} the function $f(L_a)=\max(1,L_a^{\frac{2}{3}})$, 
    9191where $L_a=0.3$\footnote{ 
    9292  This is a global average value, more accurately $L_a$ could be computed as $L_a=(u^*_{w}/u_s)^{\frac{1}{2}}$, 
     
    99994\zeta^2}{1+3\zeta+0.25\zeta^2} &(\zeta \ge 0) \\ 
    100100                                    (1 - 16\zeta)^{-\frac{1}{2}} & (\zeta < 0) \mbox{,} 
    101                                     \end{array} \right. \label{eq:stab_func_eqn} 
     101                                    \end{array} \right. \label{eq:DIU_stab_func_eqn} 
    102102\end{equation} 
    103 where $\zeta=\frac{D_T}{L}$.  It is clear that the first derivative of (\autoref{eq:stab_func_eqn}), 
    104 and thus of (\autoref{eq:ecmwf1}), is discontinuous at $\zeta=0$ (\ie\ $Q\rightarrow0$ in 
    105 equation (\autoref{eq:ecmwf2})). 
     103where $\zeta=\frac{D_T}{L}$.  It is clear that the first derivative of (\autoref{eq:DIU_stab_func_eqn}), 
     104and thus of (\autoref{eq:DIU_ecmwf1}), is discontinuous at $\zeta=0$ (\ie\ $Q\rightarrow0$ in 
     105equation (\autoref{eq:DIU_ecmwf2})). 
    106106 
    107 The two terms on the right hand side of (\autoref{eq:ecmwf1}) represent different processes. 
     107The two terms on the right hand side of (\autoref{eq:DIU_ecmwf1}) represent different processes. 
    108108The first term is simply the diabatic heating or cooling of the diurnal warm layer due to 
    109109thermal energy fluxes into and out of the layer. 
     
    114114 
    115115\section{Cool skin model} 
    116 \label{sec:cool_skin_sec} 
     116\label{sec:DIU_cool_skin_sec} 
    117117 
    118118%=============================================================== 
     
    121121As the cool skin is so thin (~1\,mm) we ignore the solar flux component to the heat flux and the Saunders equation for the cool skin temperature difference $\Delta T_{\mathrm{cs}}$ becomes 
    122122\[ 
    123   % \label{eq:sunders_eqn} 
     123  % \label{eq:DIU_sunders_eqn} 
    124124  \Delta T_{\mathrm{cs}}=\frac{Q_{\mathrm{ns}}\delta}{k_t} \mbox{,} 
    125125\] 
     
    128128$\delta$ is the thickness of the skin layer and is given by 
    129129\begin{equation} 
    130 \label{eq:sunders_thick_eqn} 
     130\label{eq:DIU_sunders_thick_eqn} 
    131131\delta=\frac{\lambda \mu}{u^*_{w}} \mbox{,} 
    132132\end{equation} 
     
    134134\citet{saunders_JAS67} suggested varied between 5 and 10. 
    135135 
    136 The value of $\lambda$ used in equation (\autoref{eq:sunders_thick_eqn}) is that of \citet{artale.iudicone.ea_JGR02}, 
     136The value of $\lambda$ used in equation (\autoref{eq:DIU_sunders_thick_eqn}) is that of \citet{artale.iudicone.ea_JGR02}, 
    137137which is shown in \citet{tu.tsuang_GRL05} to outperform a number of other parametrisations at 
    138138both low and high wind speeds. 
    139139Specifically, 
    140140\[ 
    141   % \label{eq:artale_lambda_eqn} 
     141  % \label{eq:DIU_artale_lambda_eqn} 
    142142  \lambda = \frac{ 8.64\times10^4 u^*_{w} k_t }{ \rho c_p h \mu \gamma }\mbox{,} 
    143143\] 
     
    145145$\gamma$ is a dimensionless function of wind speed $u$: 
    146146\[ 
    147   % \label{eq:artale_gamma_eqn} 
     147  % \label{eq:DIU_artale_gamma_eqn} 
    148148  \gamma = 
    149149  \begin{cases} 
Note: See TracChangeset for help on using the changeset viewer.