--- manual/s_overview/text/manual.tex 2001/09/27 17:45:03 1.1 +++ manual/s_overview/text/manual.tex 2001/10/09 10:48:03 1.2 @@ -1,27 +1,27 @@ -%%%% % $Header: /home/ubuntu/mnt/e9_copy/manual/s_overview/text/manual.tex,v 1.1 2001/09/27 17:45:03 cnh Exp $ -%%%% % $Name: $ -%%%% %\usepackage{oldgerm} -%%%% % I commented the following because it introduced excessive white space -%%%% %\usepackage{palatcm} % better PDF -%%%% % page headers and footers -%%%% %\pagestyle{fancy} -%%%% % referencing -%%%% %% \newcommand{\refequ}[1]{equation (\ref{equ:#1})} -%%%% %% \newcommand{\refequbig}[1]{Equation (\ref{equ:#1})} -%%%% %% \newcommand{\reftab}[1]{Tab.~\ref{tab:#1}} -%%%% %% \newcommand{\reftabno}[1]{\ref{tab:#1}} -%%%% %% \newcommand{\reffig}[1]{Fig.~\ref{fig:#1}} -%%%% %% \newcommand{\reffigno}[1]{\ref{fig:#1}} -%%%% % stuff for psfrag -%%%% %% \newcommand{\textinfigure}[1]{{\footnotesize\textbf{\textsf{#1}}}} -%%%% %% \newcommand{\mathinfigure}[1]{\small\ensuremath{{#1}}} -%%%% % This allows numbering of subsubsections -%%%% % This changes the the chapter title -%%%% %\renewcommand{\chaptername}{Section} +% $Header: /home/ubuntu/mnt/e9_copy/manual/s_overview/text/manual.tex,v 1.2 2001/10/09 10:48:03 cnh Exp $ +% $Name: $ +%\usepackage{oldgerm} +% I commented the following because it introduced excessive white space +%\usepackage{palatcm} % better PDF +% page headers and footers +%\pagestyle{fancy} +% referencing +%% \newcommand{\refequ}[1]{equation (\ref{equ:#1})} +%% \newcommand{\refequbig}[1]{Equation (\ref{equ:#1})} +%% \newcommand{\reftab}[1]{Tab.~\ref{tab:#1}} +%% \newcommand{\reftabno}[1]{\ref{tab:#1}} +%% \newcommand{\reffig}[1]{Fig.~\ref{fig:#1}} +%% \newcommand{\reffigno}[1]{\ref{fig:#1}} +% stuff for psfrag +%% \newcommand{\textinfigure}[1]{{\footnotesize\textbf{\textsf{#1}}}} +%% \newcommand{\mathinfigure}[1]{\small\ensuremath{{#1}}} +% This allows numbering of subsubsections +% This changes the the chapter title +%\renewcommand{\chaptername}{Section} %%%% \documentclass[12pt]{book} -%%%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% %%%% \usepackage{amsmath} %%%% \usepackage{html} %%%% \usepackage{epsfig} @@ -30,12 +30,12 @@ %%%% \usepackage{multirow} %%%% \usepackage{fancyhdr} %%%% \usepackage{psfrag} -%%%% + %%%% %TCIDATA{OutputFilter=Latex.dll} -%%%% %TCIDATA{LastRevised=Thursday, September 27, 2001 10:59:02} +%%%% %TCIDATA{LastRevised=Thursday, October 04, 2001 14:41:22} %%%% %TCIDATA{} %%%% %TCIDATA{Language=American English} -%%%% + %%%% \fancyhead{} %%%% \fancyhead[LO]{\slshape \rightmark} %%%% \fancyhead[RE]{\slshape \leftmark} @@ -45,20 +45,19 @@ %%%% \renewcommand{\headrulewidth}{0.4pt} %%%% \renewcommand{\footrulewidth}{0.4pt} %%%% \setcounter{secnumdepth}{3} -%%%% %%%% \input{tcilatex} %%%% %%%% \begin{document} %%%% %%%% \tableofcontents +%%%% +%%%% \pagebreak -\pagebreak - -\part{MITgcm basics} +%%%% \part{MIT GCM basics} % Section: Overview -% $Header: /home/ubuntu/mnt/e9_copy/manual/s_overview/text/manual.tex,v 1.1 2001/09/27 17:45:03 cnh Exp $ +% $Header: /home/ubuntu/mnt/e9_copy/manual/s_overview/text/manual.tex,v 1.2 2001/10/09 10:48:03 cnh Exp $ % $Name: $ \section{Introduction} @@ -82,39 +81,11 @@ \marginpar{ Fig.1 One model}\ref{fig:onemodel} -\begin{figure} -\begin{center} -\resizebox{!}{4in}{ - \rotatebox{90}{ - \rotatebox{180}{ - \includegraphics*[0.2in,0.7in][10.5in,10.5in]{part1/onemodel.eps} - } - } -} -\end{center} -\label{fig:onemodel} -\end{figure} - \item it has a non-hydrostatic capability and so can be used to study both small-scale and large scale processes - see fig.2% \marginpar{ Fig.2 All scales}\ref{fig:all-scales} - -\begin{figure} -\begin{center} -\resizebox{!}{4in}{ - \rotatebox{90}{ - \rotatebox{180}{ - \includegraphics*[0.2in,0.7in][10.5in,10.5in]{part1/scales.eps} - } - } -} -\end{center} -\label{fig:scales} -\end{figure} - - \item finite volume techniques are employed yielding an intuitive discretization and support for the treatment of irregular geometries using orthogonal curvilinear grids and shaved cells - see fig.3% @@ -136,7 +107,7 @@ give a feel for the wide range of problems that can be addressed using it. \pagebreak -% $Header: /home/ubuntu/mnt/e9_copy/manual/s_overview/text/manual.tex,v 1.1 2001/09/27 17:45:03 cnh Exp $ +% $Header: /home/ubuntu/mnt/e9_copy/manual/s_overview/text/manual.tex,v 1.2 2001/10/09 10:48:03 cnh Exp $ % $Name: $ \section{Illustrations of the model in action} @@ -147,115 +118,149 @@ kinds of problems the model has been used to study, we briefly describe some of them here. A more detailed description of the underlying formulation, numerical algorithm and implementation that lie behind these calculations is -given later. Indeed it is easy to reproduce the results shown here: simply -download the model (the minimum you need is a PC running linux, together -with a FORTRAN\ 77 compiler) and follow the examples. +given later. Indeed many of the illustrative examples shown below can be +easily reproduced: simply download the model (the minimum you need is a PC +running linux, together with a FORTRAN\ 77 compiler) and follow the examples +described in detail in the documentation. \subsection{Global atmosphere: `Held-Suarez' benchmark} -Fig.E1a.\ref{fig:Held-Suarez} is an instaneous plot of the 500$mb$ height -field obtained using a 5-level version of the atmospheric pressure isomorph -run at 2.8$^{\circ }$ resolution. We see fully developed baroclinic eddies -along the northern hemisphere storm track. There are no mountains or -land-sea contrast in this calculation, but you can easily put them in. The -model is driven by relaxation to a radiative-convective equilibrium profile, -following the description set out in Held and Suarez; 1994 designed to test -atmospheric hydrodynamical cores - there are no mountains or land-sea -contrast. As decribed in Adcroft (2001), a `cubed sphere' is used to -descretize the globe permitting a uniform gridding and obviated the need to -fourier filter. +A novel feature of MITgcm is its ability to simulate both atmospheric and +oceanographic flows at both small and large scales. -Fig.E1b shows the 5-year mean, zonally averaged potential temperature, zonal -wind and meridional overturning streamfunction from the 5-level model. - - -\begin{figure} -\begin{center} -\resizebox{!}{4in}{ - \rotatebox{90}{ - \includegraphics*[0.2in,0.7in][10.5in,10.5in]{part1/hscs.eps} - } -} -\end{center} -\label{fig:hscs} -\end{figure} +Fig.E1a.\ref{fig:Held-Suarez} shows an instantaneous plot of the 500$mb$ +temperature field obtained using the atmospheric isomorph of MITgcm run at +2.8$^{\circ }$ resolution on the cubed sphere. We see cold air over the pole +(blue) and warm air along an equatorial band (red). Fully developed +baroclinic eddies spawned in the northern hemisphere storm track are +evident. There are no mountains or land-sea contrast in this calculation, +but you can easily put them in. The model is driven by relaxation to a +radiative-convective equilibrium profile, following the description set out +in Held and Suarez; 1994 designed to test atmospheric hydrodynamical cores - +there are no mountains or land-sea contrast. + +As described in Adcroft (2001), a `cubed sphere' is used to discretize the +globe permitting a uniform gridding and obviated the need to fourier filter. +The `vector-invariant' form of MITgcm supports any orthogonal curvilinear +grid, of which the cubed sphere is just one of many choices. +Fig.E1b shows the 5-year mean, zonally averaged potential temperature, zonal +wind and meridional overturning streamfunction from a 20-level version of +the model. It compares favorable with more conventional spatial +discretization approaches. A regular spherical lat-lon grid can also be used. -\begin{figure} -\begin{center} -\resizebox{!}{4in}{ - \rotatebox{90}{ - \includegraphics*[0.2in,0.7in][10.5in,10.5in]{part1/hslatlon.eps} - } -} -\end{center} -\label{fig:hslatlon} -\end{figure} - \subsection{Ocean gyres} +Baroclinic instability is a ubiquitous process in the ocean, as well as the +atmosphere. Ocean eddies play an important role in modifying the +hydrographic structure and current systems of the oceans. Coarse resolution +models of the oceans cannot resolve the eddy field and yield rather broad, +diffusive patterns of ocean currents. But if the resolution of our models is +increased until the baroclinic instability process is resolved, numerical +solutions of a different and much more realistic kind, can be obtained. + +Fig. ?.? shows the surface temperature and velocity field obtained from +MITgcm run at $\frac{1}{6}^{\circ }$ horizontal resolution on a $lat-lon$ +grid in which the pole has been rotated by 90$^{\circ }$ on to the equator +(to avoid the converging of meridian in northern latitudes). 21 vertical +levels are used in the vertical with a `lopped cell' representation of +topography. The development and propagation of anomalously warm and cold +eddies can be clearly been seen in the Gulf Stream region. The transport of +warm water northward by the mean flow of the Gulf Stream is also clearly +visible. + \subsection{Global ocean circulation} Fig.E2a shows the pattern of ocean currents at the surface of a 4$^{\circ }$ -global ocean model run with 15 vertical levels. The model is driven using -monthly-mean winds with mixed boundary conditions on temperature and -salinity at the surface. Fig.E2b shows the overturning (thermohaline) -circulation. Lopped cells are used to represent topography on a regular $% -lat-lon$ grid extending from 70$^{\circ }N$ to 70$^{\circ }S$. - - -\begin{figure} -\begin{center} -\resizebox{!}{4in}{ -% \rotatebox{90}{ - \includegraphics*[0.2in,0.7in][10.5in,10.5in]{part1/ocean_circ_455_2030.eps} -% } -} -\end{center} -\label{fig:horizcirc} -\end{figure} - -\begin{figure} -\begin{center} -\resizebox{!}{4in}{ - \rotatebox{90}{ - \rotatebox{180}{ - \includegraphics*[0.2in,0.7in][10.5in,10.5in]{part1/moc.eps} - } - } -} -\end{center} -\label{fig:moc} -\end{figure} - - -\subsection{Flow over topography} - -\subsection{Ocean convection} - -Fig.E3 shows convection over a slope using the non-hydrostatic ocean -isomorph and lopped cells to respresent topography. .....The grid resolution -is +global ocean model run with 15 vertical levels. Lopped cells are used to +represent topography on a regular $lat-lon$ grid extending from 70$^{\circ +}N $ to 70$^{\circ }S$. The model is driven using monthly-mean winds with +mixed boundary conditions on temperature and salinity at the surface. The +transfer properties of ocean eddies, convection and mixing is parameterized +in this model. + +Fig.E2b shows the meridional overturning circulation of the global ocean in +Sverdrups. + +\subsection{Convection and mixing over topography} + +Dense plumes generated by localized cooling on the continental shelf of the +ocean may be influenced by rotation when the deformation radius is smaller +than the width of the cooling region. Rather than gravity plumes, the +mechanism for moving dense fluid down the shelf is then through geostrophic +eddies. The simulation shown in the figure (blue is cold dense fluid, red is +warmer, lighter fluid) employs the non-hydrostatic capability of MITgcm to +trigger convection by surface cooling. The cold, dense water falls down the +slope but is deflected along the slope by rotation. It is found that +entrainment in the vertical plane is reduced when rotational control is +strong, and replaced by lateral entrainment due to the baroclinic +instability of the along-slope current. \subsection{Boundary forced internal waves} -\subsection{Carbon outgassing sensitivity} - -Fig.E4 shows.... - -\begin{figure} -\begin{center} -\resizebox{!}{4in}{ - \includegraphics*[0.2in,0.7in][10.5in,10.5in]{part1/co209.eps} -} -\end{center} -\label{fig:co2mrt} -\end{figure} +The unique ability of MITgcm to treat non-hydrostatic dynamics in the +presence of complex geometry makes it an ideal tool to study internal wave +dynamics and mixing in oceanic canyons and ridges driven by large amplitude +barotropic tidal currents imposed through open boundary conditions. + +Fig. ?.? shows the influence of cross-slope topographic variations on +internal wave breaking - the cross-slope velocity is in color, the density +contoured. The internal waves are excited by application of open boundary +conditions on the left.\ They propagate to the sloping boundary (represented +using MITgcm's finite volume spatial discretization) where they break under +nonhydrostatic dynamics. + +\subsection{Parameter sensitivity using the adjoint of MITgcm} + +Forward and tangent linear counterparts of MITgcm are supported using an +`automatic adjoint compiler'. These can be used in parameter sensitivity and +data assimilation studies. + +As one example of application of the MITgcm adjoint, Fig.E4 maps the +gradient $\frac{\partial J}{\partial \mathcal{H}}$where $J$ is the magnitude +of the overturning streamfunction shown in fig?.? at 40$^{\circ }$N and $% +\mathcal{H}$ is the air-sea heat flux 100 years before. We see that $J$ is +sensitive to heat fluxes over the Labrador Sea, one of the important sources +of deep water for the thermohaline circulations. This calculation also +yields sensitivities to all other model parameters. + +\subsection{Global state estimation of the ocean} + +An important application of MITgcm is in state estimation of the global +ocean circulation. An appropriately defined `cost function', which measures +the departure of the model from observations (both remotely sensed and +insitu) over an interval of time, is minimized by adjusting `control +parameters' such as air-sea fluxes, the wind field, the initial conditions +etc. Figure ?.? shows an estimate of the time-mean surface elevation of the +ocean obtained by bringing the model in to consistency with altimetric and +in-situ observations over the period 1992-1997. + +\subsection{Ocean biogeochemical cycles} + +MITgcm is being used to study global biogeochemical cycles in the ocean. For +example one can study the effects of interannual changes in meteorological +forcing and upper ocean circulation on the fluxes of carbon dioxide and +oxygen between the ocean and atmosphere. The figure shows the annual air-sea +flux of oxygen and its relation to density outcrops in the southern oceans +from a single year of a global, interannually varying simulation. + +Chris - get figure here: http://puddle.mit.edu/\symbol{126}% +mick/biogeochem.html + +\subsection{Simulations of laboratory experiments} + +Figure ?.? shows MITgcm being used to simulate a laboratory experiment +enquiring in to the dynamics of the Antarctic Circumpolar Current (ACC). An +initially homogeneous tank of water ($1m$ in diameter) is driven from its +free surface by a rotating heated disk. The combined action of mechanical +and thermal forcing creates a lens of fluid which becomes baroclinically +unstable. The stratification and depth of penetration of the lens is +arrested by its instability in a process analogous to that whic sets the +stratification of the ACC. - -% $Header: /home/ubuntu/mnt/e9_copy/manual/s_overview/text/manual.tex,v 1.1 2001/09/27 17:45:03 cnh Exp $ +% $Header: /home/ubuntu/mnt/e9_copy/manual/s_overview/text/manual.tex,v 1.2 2001/10/09 10:48:03 cnh Exp $ % $Name: $ \section{Continuous equations in `r' coordinates} @@ -280,19 +285,6 @@ \marginpar{ Fig.5 The vertical coordinate of model}: -\begin{figure} -\begin{center} -\resizebox{!}{4in}{ - \rotatebox{90}{ - \rotatebox{180}{ - \includegraphics*[0.2in,0.7in][10.5in,10.5in]{part1/vertcoord.eps} - } - } -} -\end{center} -\label{fig:vertcoord} -\end{figure} - \begin{equation*} \frac{D\vec{\mathbf{v}_{h}}}{Dt}+\left( 2\vec{\Omega}\times \vec{\mathbf{v}}% \right) _{h}+\mathbf{\nabla }_{h}\phi =\mathcal{F}_{\vec{\mathbf{v}_{h}}}% @@ -311,63 +303,63 @@ \end{equation} \begin{equation*} -b=b(\theta ,S,r)\text{ equation of state} +b=b(\theta ,S,r)\text{ equation of state} \end{equation*} \begin{equation*} -\frac{D\theta }{Dt}=\mathcal{Q}_{\theta }\text{ potential temperature} +\frac{D\theta }{Dt}=\mathcal{Q}_{\theta }\text{ potential temperature} \end{equation*} \begin{equation*} -\frac{DS}{Dt}=\mathcal{Q}_{S}\text{ humidity/salinity} +\frac{DS}{Dt}=\mathcal{Q}_{S}\text{ humidity/salinity} \end{equation*} Here: \begin{equation*} -r\text{ is the vertical coordinate} +r\text{ is the vertical coordinate} \end{equation*} \begin{equation*} \frac{D}{Dt}=\frac{\partial }{\partial t}+\vec{\mathbf{v}}\cdot \nabla \text{ -is the total derivative} +is the total derivative} \end{equation*} \begin{equation*} \mathbf{\nabla }=\mathbf{\nabla }_{h}+\widehat{k}\frac{\partial }{\partial r}% -\text{ is the `grad' operator} +\text{ is the `grad' operator} \end{equation*} with $\mathbf{\nabla }_{h}$ operating in the horizontal and $\widehat{k}% \frac{\partial }{\partial r}$ operating in the vertical, where $\widehat{k}$ is a unit vector in the vertical \begin{equation*} -t\text{ is time} +t\text{ is time} \end{equation*} \begin{equation*} \vec{\mathbf{v}}=(u,v,\dot{r})=(\vec{\mathbf{v}}_{h},\dot{r})\text{ is the -velocity} +velocity} \end{equation*} \begin{equation*} -\phi \text{ is the `pressure'/`geopotential'} +\phi \text{ is the `pressure'/`geopotential'} \end{equation*} \begin{equation*} -\vec{\Omega}\text{ is the Earth's rotation} +\vec{\Omega}\text{ is the Earth's rotation} \end{equation*} \begin{equation*} -b\text{ is the `buoyancy'} +b\text{ is the `buoyancy'} \end{equation*} \begin{equation*} -\theta \text{ is potential temperature} +\theta \text{ is potential temperature} \end{equation*} \begin{equation*} -S\text{ is specific humidity in the atmosphere; salinity in the ocean} +S\text{ is specific humidity in the atmosphere; salinity in the ocean} \end{equation*} \begin{equation*} @@ -376,8 +368,7 @@ \end{equation*} \begin{equation*} -\mathcal{Q}_{\theta }\mathcal{\ }\text{are forcing and dissipation of }% -\theta +\mathcal{Q}_{\theta }\mathcal{\ }\text{are forcing and dissipation of }\theta \end{equation*} \begin{equation*} @@ -406,7 +397,7 @@ Here \begin{equation*} -R_{moving}=R_{o}+\eta +R_{moving}=R_{o}+\eta \end{equation*} where $R_{o}(x,y)$ is the `$r-$value' (height or pressure, depending on whether we are in the atmosphere or ocean) of the `moving surface' in the @@ -474,12 +465,12 @@ At the top of the atmosphere (which is `fixed' in our $r$ coordinate): \begin{equation*} -R_{fixed}=p_{top}=0 +R_{fixed}=p_{top}=0 \end{equation*} In a resting atmosphere the elevation of the mountains at the bottom is given by \begin{equation*} -R_{moving}=R_{o}(x,y)=p_{o}(x,y) +R_{moving}=R_{o}(x,y)=p_{o}(x,y) \end{equation*} i.e. the (hydrostatic) pressure at the top of the mountains in a resting atmosphere. @@ -589,7 +580,7 @@ \textit{Coriolis} \\ \textit{\ Forcing/Dissipation}% \end{tabular}% -\ \right. \qquad \label{eq:gu-speherical} +\ \right. \qquad \label{eq:gu-speherical} \end{equation} \begin{equation} @@ -608,9 +599,9 @@ \textit{Coriolis} \\ \textit{\ Forcing/Dissipation}% \end{tabular}% -\ \right. \qquad \label{eq:gv-spherical} +\ \right. \qquad \label{eq:gv-spherical} \end{equation}% -\qquad \qquad \qquad \qquad \qquad +\qquad \qquad \qquad \qquad \qquad \begin{equation} \left. @@ -627,9 +618,9 @@ \textit{Coriolis} \\ \textit{\ Forcing/Dissipation}% \end{tabular}% -\ \right. \label{eq:gw-spherical} +\ \right. \label{eq:gw-spherical} \end{equation}% -\qquad \qquad \qquad \qquad \qquad +\qquad \qquad \qquad \qquad \qquad In the above `${r}$' is the distance from the center of the earth and `$lat$% ' is latitude. @@ -639,20 +630,6 @@ \marginpar{ Fig.6 Spherical polar coordinate system.} -\begin{figure} -\begin{center} -\resizebox{!}{4in}{ - \rotatebox{90}{ - \rotatebox{180}{ - \includegraphics*[0.2in,0.7in][10.5in,10.5in]{part1/spherical-polar.eps} - } - } -} -\end{center} -\label{fig:spcoord} -\end{figure} - - \subsubsection{Shallow atmosphere approximation} Most models are based on the `hydrostatic primitive equations' (HPE's) in @@ -661,8 +638,8 @@ Coriolis force is treated approximately and the shallow atmosphere approximation is made.\ The MITgcm need not make the `traditional approximation'. To be able to support consistent non-hydrostatic forms the -shallow atmosphere approximation can be relaxed - when dividing through by $r -$ in, for example, (\ref{eq:gu-speherical}), we do not replace $r$ by $a$, +shallow atmosphere approximation can be relaxed - when dividing through by $% +r $ in, for example, (\ref{eq:gu-speherical}), we do not replace $r$ by $a$, the radius of the earth. \subsubsection{Hydrostatic and quasi-hydrostatic forms} @@ -688,7 +665,7 @@ vertical momentum equation (\ref{eq:mom-w}) becomes: \begin{equation*} -\frac{\partial \phi _{nh}}{\partial r}=2\Omega u\cos lat +\frac{\partial \phi _{nh}}{\partial r}=2\Omega u\cos lat \end{equation*} making a small correction to the hydrostatic pressure. @@ -769,20 +746,6 @@ stepping forward the horizontal momentum equations; $\dot{r}$ is found by stepping forward the vertical momentum equation. -\begin{figure} -\begin{center} -\resizebox{!}{4in}{ - \rotatebox{90}{ - \rotatebox{180}{ - \includegraphics*[0.2in,0.7in][10.5in,10.5in]{part1/soln_strategy.eps} - } - } -} -\end{center} -\label{fig:solnstart} -\end{figure} - - There is no penalty in implementing \textbf{QH} over \textbf{HPE} except, of course, some complication that goes with the inclusion of $\cos \phi \ $% Coriolis terms and the relaxation of the shallow atmosphere approximation. @@ -809,7 +772,7 @@ \begin{equation*} \int_{r}^{R_{o}}\frac{\partial \phi _{hyd}}{\partial r}dr=\left[ \phi _{hyd}% -\right] _{r}^{R_{o}}=\int_{r}^{R_{o}}-bdr +\right] _{r}^{R_{o}}=\int_{r}^{R_{o}}-bdr \end{equation*} and so @@ -831,7 +794,7 @@ \begin{equation*} \int_{R_{fixed}}^{R_{moving}}\left( \mathbf{\nabla }_{h}\cdot \vec{\mathbf{v}% -}_{h}+\partial _{r}\dot{r}\right) dr=0 +}_{h}+\partial _{r}\dot{r}\right) dr=0 \end{equation*} Thus: @@ -839,7 +802,7 @@ \begin{equation*} \frac{\partial \eta }{\partial t}+\vec{\mathbf{v}}.\nabla \eta +\int_{R_{fixed}}^{R_{moving}}\mathbf{\nabla }_{h}\cdot \vec{\mathbf{v}}% -_{h}dr=0 +_{h}dr=0 \end{equation*} where $\eta =R_{moving}-R_{o}$ is the free-surface $r$-anomaly in units of $% r $. The above can be rearranged to yield, using Leibnitz's theorem: @@ -855,7 +818,7 @@ (atmospheric model), in (\ref{mtm-split}), the horizontal gradient term can be written \begin{equation} -\mathbf{\nabla }_{h}\phi _{s}=\mathbf{\nabla }_{h}\left( b_{s}\eta \right) +\mathbf{\nabla }_{h}\phi _{s}=\mathbf{\nabla }_{h}\left( b_{s}\eta \right) \label{eq:phi-surf} \end{equation}% where $b_{s}$ is the buoyancy at the surface. @@ -914,18 +877,18 @@ presenting inhomogeneous Neumann boundary conditions to the Elliptic problem (\ref{eq:3d-invert}). As shown, for example, by Williams (1969), one can exploit classical 3D potential theory and, by introducing an appropriately -chosen $\delta $-function sheet of `source-charge', replace the inhomogenous -boundary condition on pressure by a homogeneous one. The source term $rhs$ -in (\ref{eq:3d-invert}) is the divergence of the vector $\vec{\mathbf{F}}.$ -By simultaneously setting $% +chosen $\delta $-function sheet of `source-charge', replace the +inhomogeneous boundary condition on pressure by a homogeneous one. The +source term $rhs$ in (\ref{eq:3d-invert}) is the divergence of the vector $% +\vec{\mathbf{F}}.$ By simultaneously setting $% \begin{array}{l} \widehat{n}.\vec{\mathbf{F}}% \end{array}% =0$\ and $\widehat{n}.\nabla \phi _{nh}=0\ $on the boundary the following -self-consistent but simpler homogenised Elliptic problem is obtained: +self-consistent but simpler homogenized Elliptic problem is obtained: \begin{equation*} -\nabla ^{2}\phi _{nh}=\nabla .\widetilde{\vec{\mathbf{F}}}\qquad +\nabla ^{2}\phi _{nh}=\nabla .\widetilde{\vec{\mathbf{F}}}\qquad \end{equation*}% where $\widetilde{\vec{\mathbf{F}}}$ is a modified $\vec{\mathbf{F}}$ such that $\widetilde{\vec{\mathbf{F}}}.\widehat{n}=0$. As is implied by (\ref% @@ -1000,7 +963,7 @@ \begin{equation} \frac{D\vec{\mathbf{v}}}{Dt}=\frac{\partial \vec{\mathbf{v}}}{\partial t}% +\left( \nabla \times \vec{\mathbf{v}}\right) \times \vec{\mathbf{v}}+\nabla % -\left[ \frac{1}{2}(\vec{\mathbf{v}}\cdot \vec{\mathbf{v}})\right] +\left[ \frac{1}{2}(\vec{\mathbf{v}}\cdot \vec{\mathbf{v}})\right] \label{eq:vi-identity} \end{equation}% This permits alternative numerical treatments of the non-linear terms based @@ -1013,10 +976,10 @@ \subsection{Adjoint} -Tangent linear and adoint counterparts of the forward model and described in -Chapter 5. +Tangent linear and adjoint counterparts of the forward model and described +in Chapter 5. -% $Header: /home/ubuntu/mnt/e9_copy/manual/s_overview/text/manual.tex,v 1.1 2001/09/27 17:45:03 cnh Exp $ +% $Header: /home/ubuntu/mnt/e9_copy/manual/s_overview/text/manual.tex,v 1.2 2001/10/09 10:48:03 cnh Exp $ % $Name: $ \section{Appendix ATMOSPHERE} @@ -1029,12 +992,12 @@ The hydrostatic primitive equations (HPEs) in p-coordinates are: \begin{eqnarray} \frac{D\vec{\mathbf{v}}_{h}}{Dt}+f\hat{\mathbf{k}}\times \vec{\mathbf{v}}% -_{h}+\mathbf{\nabla }_{p}\phi &=&\vec{\mathbf{\mathcal{F}}} +_{h}+\mathbf{\nabla }_{p}\phi &=&\vec{\mathbf{\mathcal{F}}} \label{eq:atmos-mom} \\ -\frac{\partial \phi }{\partial p}+\alpha &=&0 \label{eq-p-hydro-start} \\ +\frac{\partial \phi }{\partial p}+\alpha &=&0 \label{eq-p-hydro-start} \\ \mathbf{\nabla }_{p}\cdot \vec{\mathbf{v}}_{h}+\frac{\partial \omega }{% \partial p} &=&0 \label{eq:atmos-cont} \\ -p\alpha &=&RT \label{eq:atmos-eos} \\ +p\alpha &=&RT \label{eq:atmos-eos} \\ c_{v}\frac{DT}{Dt}+p\frac{D\alpha }{Dt} &=&\mathcal{Q} \label{eq:atmos-heat} \end{eqnarray}% where $\vec{\mathbf{v}}_{h}=(u,v,0)$ is the `horizontal' (on pressure @@ -1081,7 +1044,7 @@ The heat equation is obtained by noting that \begin{equation*} c_{p}\frac{DT}{Dt}=\frac{D(\Pi \theta )}{Dt}=\Pi \frac{D\theta }{Dt}+\theta -\frac{D\Pi }{Dt}=\Pi \frac{D\theta }{Dt}+\alpha \frac{Dp}{Dt} +\frac{D\Pi }{Dt}=\Pi \frac{D\theta }{Dt}+\alpha \frac{Dp}{Dt} \end{equation*} and on substituting into (\ref{eq-p-heat-interim}) gives: \begin{equation} @@ -1143,7 +1106,7 @@ \frac{D\theta }{Dt} &=&\frac{\mathcal{Q}}{\Pi } \label{eq:atmos-prime} \end{eqnarray} -% $Header: /home/ubuntu/mnt/e9_copy/manual/s_overview/text/manual.tex,v 1.1 2001/09/27 17:45:03 cnh Exp $ +% $Header: /home/ubuntu/mnt/e9_copy/manual/s_overview/text/manual.tex,v 1.2 2001/10/09 10:48:03 cnh Exp $ % $Name: $ \section{Appendix OCEAN} @@ -1160,7 +1123,7 @@ &=&\epsilon _{nh}\mathcal{F}_{w} \\ \frac{1}{\rho }\frac{D\rho }{Dt}+\mathbf{\nabla }_{z}\cdot \vec{\mathbf{v}}% _{h}+\frac{\partial w}{\partial z} &=&0 \\ -\rho &=&\rho (\theta ,S,p) \\ +\rho &=&\rho (\theta ,S,p) \\ \frac{D\theta }{Dt} &=&\mathcal{Q}_{\theta } \\ \frac{DS}{Dt} &=&\mathcal{Q}_{s} \label{eq:non-boussinesq} \end{eqnarray}% @@ -1242,14 +1205,14 @@ pressure in the EOS by splitting the pressure into a reference function of height and a perturbation: \begin{equation*} -\rho =\rho (\theta ,S,p_{o}(z)+\epsilon _{s}p^{\prime }) +\rho =\rho (\theta ,S,p_{o}(z)+\epsilon _{s}p^{\prime }) \end{equation*} Remembering that the term $\frac{Dp}{Dt}$ in continuity comes from differentiating the EOS, the continuity equation then becomes: \begin{equation*} \frac{1}{\rho _{o}c_{s}^{2}}\left( \frac{Dp_{o}}{Dt}+\epsilon _{s}\frac{% Dp^{\prime }}{Dt}\right) +\mathbf{\nabla }_{z}\cdot \vec{\mathbf{v}}_{h}+% -\frac{\partial w}{\partial z}=0 +\frac{\partial w}{\partial z}=0 \end{equation*} If the time- and space-scales of the motions of interest are longer than those of acoustic modes, then $\frac{Dp^{\prime }}{Dt}<<(\frac{Dp_{o}}{Dt},% @@ -1359,7 +1322,7 @@ _{nh}=0$ form of these equations that are used throughout the ocean modeling community and referred to as the primitive equations (HPE). -% $Header: /home/ubuntu/mnt/e9_copy/manual/s_overview/text/manual.tex,v 1.1 2001/09/27 17:45:03 cnh Exp $ +% $Header: /home/ubuntu/mnt/e9_copy/manual/s_overview/text/manual.tex,v 1.2 2001/10/09 10:48:03 cnh Exp $ % $Name: $ \section{Appendix:OPERATORS} @@ -1372,16 +1335,16 @@ and vertical direction respectively, are given by (see Fig.2) : \begin{equation*} -u=r\cos \phi \frac{D\lambda }{Dt} +u=r\cos \phi \frac{D\lambda }{Dt} \end{equation*} \begin{equation*} -v=r\frac{D\phi }{Dt}\qquad +v=r\frac{D\phi }{Dt}\qquad \end{equation*} $\qquad \qquad \qquad \qquad $ \begin{equation*} -\dot{r}=\frac{Dr}{Dt} +\dot{r}=\frac{Dr}{Dt} \end{equation*} Here $\phi $ is the latitude, $\lambda $ the longitude, $r$ the radial @@ -1394,13 +1357,13 @@ \begin{equation*} \nabla \equiv \left( \frac{1}{r\cos \phi }\frac{\partial }{\partial \lambda }% ,\frac{1}{r}\frac{\partial }{\partial \phi },\frac{\partial }{\partial r}% -\right) +\right) \end{equation*} \begin{equation*} \nabla .v\equiv \frac{1}{r\cos \phi }\left\{ \frac{\partial u}{\partial \lambda }+\frac{\partial }{\partial \phi }\left( v\cos \phi \right) \right\} -+\frac{1}{r^{2}}\frac{\partial \left( r^{2}\dot{r}\right) }{\partial r} ++\frac{1}{r^{2}}\frac{\partial \left( r^{2}\dot{r}\right) }{\partial r} \end{equation*} %%%% \end{document}