| 10 |
|
|
| 11 |
The hydrostatic primitive equations (HPEs) in p-coordinates are: |
The hydrostatic primitive equations (HPEs) in p-coordinates are: |
| 12 |
\begin{eqnarray} |
\begin{eqnarray} |
| 13 |
\frac{D\vec{\mathbf{v}}_{h}}{Dt}+f\hat{\mathbf{k}}\times \vec{\mathbf{v}}% |
\frac{D\vec{\mathbf{v}}_{h}}{Dt}+f\hat{\mathbf{k}}\times \vec{\mathbf{v}} |
| 14 |
_{h}+\mathbf{\nabla }_{p}\phi &=&\vec{\mathbf{\mathcal{F}}} |
_{h}+\mathbf{\nabla }_{p}\phi &=&\vec{\mathbf{\mathcal{F}}} |
| 15 |
\label{eq:atmos-mom} \\ |
\label{eq:atmos-mom} \\ |
| 16 |
\frac{\partial \phi }{\partial p}+\alpha &=&0 \label{eq-p-hydro-start} \\ |
\frac{\partial \phi }{\partial p}+\alpha &=&0 \label{eq-p-hydro-start} \\ |
| 17 |
\mathbf{\nabla }_{p}\cdot \vec{\mathbf{v}}_{h}+\frac{\partial \omega }{% |
\mathbf{\nabla }_{p}\cdot \vec{\mathbf{v}}_{h}+\frac{\partial \omega }{ |
| 18 |
\partial p} &=&0 \label{eq:atmos-cont} \\ |
\partial p} &=&0 \label{eq:atmos-cont} \\ |
| 19 |
p\alpha &=&RT \label{eq:atmos-eos} \\ |
p\alpha &=&RT \label{eq:atmos-eos} \\ |
| 20 |
c_{v}\frac{DT}{Dt}+p\frac{D\alpha }{Dt} &=&\mathcal{Q} |
c_{v}\frac{DT}{Dt}+p\frac{D\alpha }{Dt} &=&\mathcal{Q} |
| 24 |
surfaces) component of velocity,$\frac{D}{Dt}=\vec{\mathbf{v}}_{h}\cdot |
surfaces) component of velocity,$\frac{D}{Dt}=\vec{\mathbf{v}}_{h}\cdot |
| 25 |
\mathbf{\nabla }_{p}+\omega \frac{\partial }{\partial p}$ is the total |
\mathbf{\nabla }_{p}+\omega \frac{\partial }{\partial p}$ is the total |
| 26 |
derivative, $f=2\Omega \sin lat$ is the Coriolis parameter, $\phi =gz$ is |
derivative, $f=2\Omega \sin lat$ is the Coriolis parameter, $\phi =gz$ is |
| 27 |
the geopotential, $\alpha =1/\rho $ is the specific volume, $\omega =\frac{Dp% |
the geopotential, $\alpha =1/\rho $ is the specific volume, $\omega =\frac{Dp |
| 28 |
}{Dt}$ is the vertical velocity in the $p-$coordinate. Equation \ref |
}{Dt}$ is the vertical velocity in the $p-$coordinate. Equation \ref |
| 29 |
{eq-p-firstlaw} is the first law of thermodynamics where internal energy $% |
{eq-p-firstlaw} is the first law of thermodynamics where internal energy $ |
| 30 |
e=c_{v}T$, $T$ is temperature, $Q$ is the rate of heating per unit mass and $% |
e=c_{v}T$, $T$ is temperature, $Q$ is the rate of heating per unit mass and $ |
| 31 |
p\frac{D\alpha }{Dt}$ is the work done by the fluid in compressing. |
p\frac{D\alpha }{Dt}$ is the work done by the fluid in compressing. |
| 32 |
|
|
| 33 |
It is convenient to cast the heat equation in terms of potential temperature |
It is convenient to cast the heat equation in terms of potential temperature |
| 36 |
\[ |
\[ |
| 37 |
p\frac{D\alpha }{Dt}+\alpha \frac{Dp}{Dt}=R\frac{DT}{Dt} |
p\frac{D\alpha }{Dt}+\alpha \frac{Dp}{Dt}=R\frac{DT}{Dt} |
| 38 |
\] |
\] |
| 39 |
which, when added to the heat equation \ref{eq-p-firstlaw} and using $% |
which, when added to the heat equation \ref{eq-p-firstlaw} and using $ |
| 40 |
c_{p}=c_{v}+R$, gives: |
c_{p}=c_{v}+R$, gives: |
| 41 |
\begin{equation} |
\begin{equation} |
| 42 |
c_{p}\frac{DT}{Dt}-\alpha \frac{Dp}{Dt}=\mathcal{Q} |
c_{p}\frac{DT}{Dt}-\alpha \frac{Dp}{Dt}=\mathcal{Q} |
| 55 |
the Exner function: |
the Exner function: |
| 56 |
\[ |
\[ |
| 57 |
c_{p}T=\Pi \theta \;\;;\;\;\frac{\partial \Pi }{\partial p}=\frac{\kappa \Pi |
c_{p}T=\Pi \theta \;\;;\;\;\frac{\partial \Pi }{\partial p}=\frac{\kappa \Pi |
| 58 |
}{p}\;\;;\;\;\alpha =\frac{\kappa \Pi \theta }{p}=\frac{\partial \ \Pi }{% |
}{p}\;\;;\;\;\alpha =\frac{\kappa \Pi \theta }{p}=\frac{\partial \ \Pi }{ |
| 59 |
\partial p}\theta \;\;;\;\;\frac{D\Pi }{Dt}=\frac{\partial \Pi }{\partial p}% |
\partial p}\theta \;\;;\;\;\frac{D\Pi }{Dt}=\frac{\partial \Pi }{\partial p} |
| 60 |
\frac{Dp}{Dt} |
\frac{Dp}{Dt} |
| 61 |
\] |
\] |
| 62 |
where $b=\frac{\partial \ \Pi }{\partial p}\theta $ is the buoyancy. |
where $b=\frac{\partial \ \Pi }{\partial p}\theta $ is the buoyancy. |
| 72 |
\end{equation} |
\end{equation} |
| 73 |
which is in conservative form. |
which is in conservative form. |
| 74 |
|
|
| 75 |
For convenience in the model we prefer to step forward (\ref{theta-equation}% |
For convenience in the model we prefer to step forward (\ref{theta-equation} |
| 76 |
) rather than (\ref{eq-p-firstlaw}). |
) rather than (\ref{eq-p-firstlaw}). |
| 77 |
|
|
| 78 |
\subsubsection{Boundary conditions} |
\subsubsection{Boundary conditions} |
| 116 |
|
|
| 117 |
The final form of the HPE's in p coordinates is then: |
The final form of the HPE's in p coordinates is then: |
| 118 |
\begin{eqnarray} |
\begin{eqnarray} |
| 119 |
\frac{D\vec{\mathbf{v}}_{h}}{Dt}+f\hat{\mathbf{k}}\times \vec{\mathbf{v}}% |
\frac{D\vec{\mathbf{v}}_{h}}{Dt}+f\hat{\mathbf{k}}\times \vec{\mathbf{v}} |
| 120 |
_{h}+\mathbf{\nabla }_{p}\phi ^{\prime } &=&\vec{\mathbf{\mathcal{F}}} |
_{h}+\mathbf{\nabla }_{p}\phi ^{\prime } &=&\vec{\mathbf{\mathcal{F}}} |
| 121 |
\\ |
\\ |
| 122 |
\frac{\partial \phi ^{\prime }}{\partial p}+\alpha ^{\prime } &=&0 |
\frac{\partial \phi ^{\prime }}{\partial p}+\alpha ^{\prime } &=&0 |
| 123 |
\\ |
\\ |
| 124 |
\mathbf{\nabla }_{p}\cdot \vec{\mathbf{v}}_{h}+\frac{\partial \omega }{% |
\mathbf{\nabla }_{p}\cdot \vec{\mathbf{v}}_{h}+\frac{\partial \omega }{ |
| 125 |
\partial p} &=&0 \\ |
\partial p} &=&0 \\ |
| 126 |
\frac{\partial \Pi }{\partial p}\theta ^{\prime } &=&\alpha ^{\prime } |
\frac{\partial \Pi }{\partial p}\theta ^{\prime } &=&\alpha ^{\prime } |
| 127 |
\\ |
\\ |