83 |
computational platforms. |
computational platforms. |
84 |
\end{itemize} |
\end{itemize} |
85 |
|
|
86 |
Key publications reporting on and charting the development of the model are |
Key publications reporting on and charting the development of the model are: |
87 |
listed in an Appendix. |
|
88 |
|
\begin{verbatim} |
89 |
|
|
90 |
|
Hill, C. and J. Marshall, (1995) |
91 |
|
Application of a Parallel Navier-Stokes Model to Ocean Circulation in |
92 |
|
Parallel Computational Fluid Dynamics |
93 |
|
In Proceedings of Parallel Computational Fluid Dynamics: Implementations |
94 |
|
and Results Using Parallel Computers, 545-552. |
95 |
|
Elsevier Science B.V.: New York |
96 |
|
|
97 |
|
Marshall, J., C. Hill, L. Perelman, and A. Adcroft, (1997) |
98 |
|
Hydrostatic, quasi-hydrostatic, and nonhydrostatic ocean modeling, |
99 |
|
J. Geophysical Res., 102(C3), 5733-5752. |
100 |
|
|
101 |
|
Marshall, J., A. Adcroft, C. Hill, L. Perelman, and C. Heisey, (1997) |
102 |
|
A finite-volume, incompressible Navier Stokes model for studies of the ocean |
103 |
|
on parallel computers, |
104 |
|
J. Geophysical Res., 102(C3), 5753-5766. |
105 |
|
|
106 |
|
Adcroft, A.J., Hill, C.N. and J. Marshall, (1997) |
107 |
|
Representation of topography by shaved cells in a height coordinate ocean |
108 |
|
model |
109 |
|
Mon Wea Rev, vol 125, 2293-2315 |
110 |
|
|
111 |
|
Marshall, J., Jones, H. and C. Hill, (1998) |
112 |
|
Efficient ocean modeling using non-hydrostatic algorithms |
113 |
|
Journal of Marine Systems, 18, 115-134 |
114 |
|
|
115 |
|
Adcroft, A., Hill C. and J. Marshall: (1999) |
116 |
|
A new treatment of the Coriolis terms in C-grid models at both high and low |
117 |
|
resolutions, |
118 |
|
Mon. Wea. Rev. Vol 127, pages 1928-1936 |
119 |
|
|
120 |
|
Hill, C, Adcroft,A., Jamous,D., and J. Marshall, (1999) |
121 |
|
A Strategy for Terascale Climate Modeling. |
122 |
|
In Proceedings of the Eighth ECMWF Workshop on the Use of Parallel Processors |
123 |
|
in Meteorology, pages 406-425 |
124 |
|
World Scientific Publishing Co: UK |
125 |
|
|
126 |
|
Marotzke, J, Giering,R., Zhang, K.Q., Stammer,D., Hill,C., and T.Lee, (1999) |
127 |
|
Construction of the adjoint MIT ocean general circulation model and |
128 |
|
application to Atlantic heat transport variability |
129 |
|
J. Geophysical Res., 104(C12), 29,529-29,547. |
130 |
|
|
131 |
|
|
132 |
|
\end{verbatim} |
133 |
|
|
134 |
We begin by briefly showing some of the results of the model in action to |
We begin by briefly showing some of the results of the model in action to |
135 |
give a feel for the wide range of problems that can be addressed using it. |
give a feel for the wide range of problems that can be addressed using it. |
147 |
numerical algorithm and implementation that lie behind these calculations is |
numerical algorithm and implementation that lie behind these calculations is |
148 |
given later. Indeed many of the illustrative examples shown below can be |
given later. Indeed many of the illustrative examples shown below can be |
149 |
easily reproduced: simply download the model (the minimum you need is a PC |
easily reproduced: simply download the model (the minimum you need is a PC |
150 |
running linux, together with a FORTRAN\ 77 compiler) and follow the examples |
running Linux, together with a FORTRAN\ 77 compiler) and follow the examples |
151 |
described in detail in the documentation. |
described in detail in the documentation. |
152 |
|
|
153 |
\subsection{Global atmosphere: `Held-Suarez' benchmark} |
\subsection{Global atmosphere: `Held-Suarez' benchmark} |
171 |
%% CNHend |
%% CNHend |
172 |
|
|
173 |
As described in Adcroft (2001), a `cubed sphere' is used to discretize the |
As described in Adcroft (2001), a `cubed sphere' is used to discretize the |
174 |
globe permitting a uniform gridding and obviated the need to Fourier filter. |
globe permitting a uniform griding and obviated the need to Fourier filter. |
175 |
The `vector-invariant' form of MITgcm supports any orthogonal curvilinear |
The `vector-invariant' form of MITgcm supports any orthogonal curvilinear |
176 |
grid, of which the cubed sphere is just one of many choices. |
grid, of which the cubed sphere is just one of many choices. |
177 |
|
|
208 |
visible. |
visible. |
209 |
|
|
210 |
%% CNHbegin |
%% CNHbegin |
211 |
\input{part1/ocean_gyres_figure} |
\input{part1/atl6_figure} |
212 |
%% CNHend |
%% CNHend |
213 |
|
|
214 |
|
|
276 |
|
|
277 |
As one example of application of the MITgcm adjoint, Figure \ref{fig:hf-sensitivity} |
As one example of application of the MITgcm adjoint, Figure \ref{fig:hf-sensitivity} |
278 |
maps the gradient $\frac{\partial J}{\partial \mathcal{H}}$where $J$ is the magnitude |
maps the gradient $\frac{\partial J}{\partial \mathcal{H}}$where $J$ is the magnitude |
279 |
of the overturning streamfunction shown in figure \ref{fig:large-scale-circ} |
of the overturning stream-function shown in figure \ref{fig:large-scale-circ} |
280 |
at 60$^{\circ }$N and $ |
at 60$^{\circ }$N and $ |
281 |
\mathcal{H}(\lambda,\varphi)$ is the mean, local air-sea heat flux over |
\mathcal{H}(\lambda,\varphi)$ is the mean, local air-sea heat flux over |
282 |
a 100 year period. We see that $J$ is |
a 100 year period. We see that $J$ is |
293 |
An important application of MITgcm is in state estimation of the global |
An important application of MITgcm is in state estimation of the global |
294 |
ocean circulation. An appropriately defined `cost function', which measures |
ocean circulation. An appropriately defined `cost function', which measures |
295 |
the departure of the model from observations (both remotely sensed and |
the departure of the model from observations (both remotely sensed and |
296 |
insitu) over an interval of time, is minimized by adjusting `control |
in-situ) over an interval of time, is minimized by adjusting `control |
297 |
parameters' such as air-sea fluxes, the wind field, the initial conditions |
parameters' such as air-sea fluxes, the wind field, the initial conditions |
298 |
etc. Figure \ref{fig:assimilated-globes} shows an estimate of the time-mean |
etc. Figure \ref{fig:assimilated-globes} shows the large scale planetary |
299 |
surface elevation of the ocean obtained by bringing the model in to |
circulation and a Hopf-Muller plot of Equatorial sea-surface height. |
300 |
|
Both are obtained from assimilation bringing the model in to |
301 |
consistency with altimetric and in-situ observations over the period |
consistency with altimetric and in-situ observations over the period |
302 |
1992-1997. {\bf CHANGE THIS TEXT - FIG FROM PATRICK/CARL/DETLEF} |
1992-1997. |
303 |
|
|
304 |
%% CNHbegin |
%% CNHbegin |
305 |
\input{part1/globes_figure} |
\input{part1/assim_figure} |
306 |
%% CNHend |
%% CNHend |
307 |
|
|
308 |
\subsection{Ocean biogeochemical cycles} |
\subsection{Ocean biogeochemical cycles} |
323 |
\subsection{Simulations of laboratory experiments} |
\subsection{Simulations of laboratory experiments} |
324 |
|
|
325 |
Figure \ref{fig:lab-simulation} shows MITgcm being used to simulate a |
Figure \ref{fig:lab-simulation} shows MITgcm being used to simulate a |
326 |
laboratory experiment enquiring in to the dynamics of the Antarctic Circumpolar Current (ACC). An |
laboratory experiment inquiring in to the dynamics of the Antarctic Circumpolar Current (ACC). An |
327 |
initially homogeneous tank of water ($1m$ in diameter) is driven from its |
initially homogeneous tank of water ($1m$ in diameter) is driven from its |
328 |
free surface by a rotating heated disk. The combined action of mechanical |
free surface by a rotating heated disk. The combined action of mechanical |
329 |
and thermal forcing creates a lens of fluid which becomes baroclinically |
and thermal forcing creates a lens of fluid which becomes baroclinically |
478 |
|
|
479 |
\begin{equation} |
\begin{equation} |
480 |
\dot{r}=\frac{Dr}{Dt}atr=R_{moving}\text{ \ |
\dot{r}=\frac{Dr}{Dt}atr=R_{moving}\text{ \ |
481 |
(oceansurface,bottomoftheatmosphere)} \label{eq:movingbc} |
(ocean surface,bottom of the atmosphere)} \label{eq:movingbc} |
482 |
\end{equation} |
\end{equation} |
483 |
|
|
484 |
Here |
Here |
1224 |
\label{eq:non-boussinesq} |
\label{eq:non-boussinesq} |
1225 |
\end{eqnarray} |
\end{eqnarray} |
1226 |
These equations permit acoustics modes, inertia-gravity waves, |
These equations permit acoustics modes, inertia-gravity waves, |
1227 |
non-hydrostatic motions, a geostrophic (Rossby) mode and a thermo-haline |
non-hydrostatic motions, a geostrophic (Rossby) mode and a thermohaline |
1228 |
mode. As written, they cannot be integrated forward consistently - if we |
mode. As written, they cannot be integrated forward consistently - if we |
1229 |
step $\rho $ forward in (\ref{eq-zns-cont}), the answer will not be |
step $\rho $ forward in (\ref{eq-zns-cont}), the answer will not be |
1230 |
consistent with that obtained by stepping (\ref{eq-zns-heat}) and (\ref |
consistent with that obtained by stepping (\ref{eq-zns-heat}) and (\ref |