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make docs match paper. (#2006)
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AMLattanzi authored Dec 6, 2024
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2 changes: 1 addition & 1 deletion Docs/sphinx_doc/theory/Buoyancy.rst
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Expand Up @@ -5,7 +5,7 @@
.. role:: f(code)
:language: fortran

.. _sec:Buoyancy:
.. _Buoyancy:

ERF has several options for how to define the buoyancy force.

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38 changes: 19 additions & 19 deletions Docs/sphinx_doc/theory/DryEquations.rst
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Expand Up @@ -16,21 +16,20 @@ in the second, ERF solves a modified set of equations which approximates the den
hydrostatic density and imposes the anelastic constraint on the velocity field.

In compressible mode, in the absence of moisture, ERF solves the following partial differential equations
expressing conservation of mass, momentum, potential temperature, and scalars.
expressing conservation of mass :math:`(\rho)`, momentum :math:`(\rho \mathbf{u})`, potential temperature :math:`(\rho \theta_{d})`, and scalars :math:`(\rho \mathbf{\phi})`:

.. math::
\frac{\partial \rho}{\partial t} &= - \nabla \cdot (\rho \mathbf{u}),
\frac{\partial \rho_d}{\partial t} = - \nabla \cdot (\rho_d \mathbf{u}),
\frac{\partial (\rho \mathbf{u})}{\partial t} &= - \nabla \cdot (\rho \mathbf{u} \mathbf{u}) - \nabla p^\prime
+ \delta_{i,3}\mathbf{B} - \nabla \cdot \tau + \mathbf{F},
\frac{\partial (\rho_d \mathbf{u})}{\partial t} = - \nabla \cdot (\rho_d \mathbf{u} \mathbf{u}) - \frac{1}{1 + q_v + q_c} ( \nabla p^\prime - \delta_{i,3}\mathbf{B} ) - \nabla \cdot \boldsymbol{\tau} + \mathbf{F}_{u},
\frac{\partial (\rho \theta)}{\partial t} &= - \nabla \cdot (\rho \mathbf{u} \theta) + \nabla \cdot ( \rho \alpha_{T}\ \nabla \theta) + F_{\rho \theta},
\frac{\partial (\rho_d \theta_d)}{\partial t} = - \nabla \cdot (\rho_d \mathbf{u} \theta_d) + \nabla \cdot ( \rho_d \alpha_{\theta}\ \nabla \theta_d) + F_{\theta},
\frac{\partial (\rho C)}{\partial t} &= - \nabla \cdot (\rho \mathbf{u} C) + \nabla \cdot (\rho \alpha_{C}\ \nabla C)
\frac{\partial (\rho_d \boldsymbol{\phi})}{\partial t} &= - \nabla \cdot (\rho_d \mathbf{u} \boldsymbol{\phi}) + \nabla \cdot ( \rho_d \alpha_{\phi}\ \nabla \boldsymbol{\phi}) + \mathbf{F}_{\phi}.
where

- :math:`\tau` is the viscous stress tensor,
- :math:`\boldsymbol{\tau}` is the viscous stress tensor,

.. math::
\tau_{ij} = -2\mu \sigma_{ij},
Expand All @@ -41,24 +40,25 @@ with :math:`\sigma_{ij} = S_{ij} -D_{ij}` being the deviatoric part of the strai
S_{ij} = \frac{1}{2} \left( \frac{\partial u_i}{\partial x_j} + \frac{\partial u_j}{\partial x_i} \right), \hspace{24pt}
D_{ij} = \frac{1}{3} S_{kk} \delta_{ij} = \frac{1}{3} (\nabla \cdot \mathbf{u}) \delta_{ij},
- :math:`\mathbf{F}` and :math:`F_{\rho \theta}` are the forcing terms described in :ref:`Forcings`,
- :math:`\mathbf{F}_{u}` and :math:`F_{\theta_d}` are the forcing terms described in :ref:`Forcings`,
- :math:`\mathbf{B} = -(\rho - \rho_{0})\mathbf{g}` is the buoyancy term described in :ref:`sec:Buoyancy <Buoyancy>`,
- :math:`\mathbf{g} = (0,0,-g)` is the gravity vector,
- the potential temperature :math:`\theta` is defined from temperature :math:`T` and pressure :math:`p` as
- the dry potential temperature :math:`\theta_d` is defined from temperature :math:`T`, pressure :math:`p`, and reference pressure :math:`P_{00} = 10^{5}` Pa as

.. math::
\theta = T \left( \frac{p_0}{p} \right)^{R_d / c_p}.
\theta_d = T \left( \frac{P_{00}}{p} \right)^{R_d / c_p}.
- pressure and density are defined as perturbations from a hydrostatically stratified background state, i.e.
.. math::
p = \overline{p}(z) + p^\prime \hspace{24pt} \rho = \overline{\rho}(z) + \rho^\prime
p = p_{0}(z) + p^\prime \hspace{24pt} \rho = \rho_{0}(z) + \rho^\prime
with

.. math::
\frac{d \overline{p}}{d z} = - \overline{\rho} g
\frac{d p_{0}}{d z} = - \rho_{0} g
We note that there is an alternative option under development in ERF that solves the governing
equations with an anelastic constraint rather than the fully compressible equations. The equation set is described below.
Expand All @@ -74,27 +74,27 @@ The assumptions involved in deriving these equations from first principles are:
- Viscous heating is negligible
- No chemical reactions, second order diffusive processes or radiative heat transfer
- Newtonian viscous stress with no bulk viscosity contribution (i.e., :math:`\kappa S_{kk} \delta_{ij}`)
- Depending on the simulation mode, the transport coefficients :math:`\mu`, :math:`\rho\alpha_C`, and
:math:`\rho\alpha_T` may correspond to the molecular transport coefficients, turbulent transport
- Depending on the simulation mode, the transport coefficients :math:`\mu`, :math:`\rho\alpha_{\phi}`, and
:math:`\rho\alpha_{\theta}` may correspond to the molecular transport coefficients, turbulent transport
coefficients computed from an LES or PBL model, or a combination. See the sections on :ref:`DNS vs. LES modes <DNSvsLES>`
and :ref:`PBL schemes <PBLschemes>` for more details.

Diagnostic Relationships
------------------------

In order to close the above prognostic equations, a relationship between the pressure and the other state variables
must be specified. This is obtained by re-expressing the ideal gas equation of state in terms of :math:`\theta`:
must be specified. This is obtained by re-expressing the ideal gas equation of state in terms of :math:`\theta_{d}`:

.. math::
p = \left( \frac{\rho R_d \theta}{p_0^{R_d / c_p}} \right)^\gamma = p_0 \left( \frac{\rho R_d \theta}{p_0} \right)^\gamma
p = \left( \frac{\rho R_d \theta_{d}}{P_{00}^{R_d / c_p}} \right)^\gamma = P_{00} \left( \frac{\rho R_d \theta_{d}}{P_{00}} \right)^\gamma
Nomenclature
------------
Here :math:`\rho, T, \theta`, and :math:`p` are the density, temperature, potential temperature and pressure, respectively;
Here :math:`\rho, T, \theta_{d}`, and :math:`p` are the density, temperature, dry potential temperature and pressure, respectively;
these variables are all defined at cell centers.
:math:`C` is an advected quantity, i.e., a tracer, also defined at cell centers.
:math:`\phi` is an advected scalar, also defined at cell centers.
:math:`\mathbf{u}` and :math:`(\rho \mathbf{u})` are the velocity and momentum, respectively,
and are defined on faces.

:math:`R_d` and :math:`c_p` are the gas constant and specific heat capacity for dry air respectively,
and :math:`\gamma = c_p / (c_p - R_d)` . :math:`p_0` is a reference value for pressure.
and :math:`\gamma = c_p / (c_p - R_d)` . :math:`P_{00}` is a reference value for pressure.
25 changes: 19 additions & 6 deletions Docs/sphinx_doc/theory/Microphysics.rst
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Expand Up @@ -20,15 +20,28 @@ Governing equations for the microphysical quantities for Kessler microphysics fr
.. math::
\frac{\partial q_c}{\partial t} = C_c - E_c - (A_c + K_c)
.. math::
\frac{\partial q_p}{\partial t} = \frac{1}{\overline{\rho}}\frac{\partial}{\partial z}(\overline{\rho}Vq_p) + (A_c + K_c) - E_r
\frac{\partial q_p}{\partial t} = \frac{1}{\rho_{d}}\frac{\partial}{\partial z}(\rho_{d} w_{t} q_p) + (A_c + K_c) - E_r
.. math::
\frac{\partial q_t}{\partial t} = \frac{\partial q_v}{\partial t} + \frac{\partial q_c}{\partial t}
= E_r - (A_c + K_c)
where :math:`C_c` is the rate of condensation of water vapor to cloud water, :math:`E_c` is the rate of evaporation of cloud water to water vapor,
:math:`A_c` is the autoconversion of cloud water to rain, :math:`K_c` is the accretion of cloud water to rain drops, :math:`E_r` is the evaporation of
rain to water vapor and :math:`F_r` is the sedimentation of rain. The parametrization used is given in `klemp1978simulation`_, and is given
below. Note that in all the equations, :math:`p` is specified in millibars and :math:`\overline{\rho}` is specified in g cm :math:`^{-3}`. The parametrization
rain to water vapor and :math:`F_r = \rho_{d} w_{t} q_p` is the sedimentation flux. The source terms that enter into the governing equations are then given by:

.. math::
\mathbf{F_{n}} \equiv [F_{q_v}, F_{q_c}] = \left[ -C_c, \;\; C_c \right],
\mathbf{G_{p}} = \left[ E_r, \;\; -A_c - K_c \right],
H_{n} = \rho_d \frac{L_v}{c_p} \frac{\theta_d}{T} C_c,
F_{p} = A_c + K_c - E_c,
H_{p} = -\rho_d \frac{L_v}{c_p} \frac{\theta_d}{T} E_r.
The parametrizations provided in `klemp1978simulation`_ are given below for each term.
Note that in all the equations, :math:`p` is specified in millibars and :math:`\overline{\rho}` is specified in g cm :math:`^{-3}`. The parametrization
of the source terms are given below.

.. _`gabervsek2012dry`: https://journals.ametsoc.org/view/journals/mwre/140/10/mwr-d-11-00144.1.xml
Expand All @@ -47,12 +60,12 @@ From `klemp1978simulation`_, we have the following expressions.
If the air is not saturated, i.e. :math:`q_v > q_{vs}`

.. math::
C_c = \frac{q_v - q_{vs}}{1 + \cfrac{q_{vs}^*4093L}{C_p(T-36)^2}}
C_c = \frac{q_v - q_{vs}}{1 + \cfrac{q_{vs}^*4093L}{c_p(T-36)^2}}
If the air is not saturated, i.e. :math:`q_v < q_{vs}`, then cloud water evaporates to water vapor at the rate

.. math::
E_c = \frac{q_{vs} - q_v}{1 + \cfrac{q_{vs}^*4093L}{C_p(T-36)^2}}
E_c = \frac{q_{vs} - q_v}{1 + \cfrac{q_{vs}^*4093L}{c_p(T-36)^2}}
Rate of autoconversion of cloud water into rain
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Expand Down Expand Up @@ -90,7 +103,7 @@ Terminal fall velocity of rain
The terminal fall velocity of rain is given by

.. math::
V = 3634(\overline{\rho}q_r)^{0.1346}\Bigg(\cfrac{\overline{\rho}}{\rho_0}\Bigg)^{-\frac{1}{2}}~\text{[cm/s]}
w_{t} = 3634(\overline{\rho}q_r)^{0.1346}\Bigg(\cfrac{\overline{\rho}}{\rho_0}\Bigg)^{-\frac{1}{2}}~\text{[cm/s]}
.. raw:: latex

Expand Down
52 changes: 23 additions & 29 deletions Docs/sphinx_doc/theory/WetEquations.rst
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Expand Up @@ -16,7 +16,7 @@ Model 1: Warm Moisture with no Precipitation
With this model, which is analogous to that in FASTEddy, we
consider a mixture of dry air :math:`\rho_d` and nonprecipitating water vapor :math:`\rho_v`,
assumed to be a perfect ideal gas with constant heat capacities
:math:`C_{vd}`, :math:`C_{vv}`, :math:`C_{pd}`, :math:`C_{pv}`, and
:math:`c_{vd}`, :math:`c_{vv}`, :math:`c_{pd}`, :math:`c_{pv}`, and
(non-precipitating) cloud water :math:`\rho_c`.

Neglecting the volume occupied by all water not in vapor form, we have
Expand All @@ -32,30 +32,28 @@ relative to the density of dry air, i.e. :math:`q_s = \frac{\rho_s}{\rho_d}`.

Governing Equations
-------------------
The governing equations for this model are
The governing equations without precipitating moisture variables are

.. math::
\frac{\partial \rho_d}{\partial t} &= - \nabla \cdot (\rho_d \mathbf{u})
\frac{\partial \rho_d}{\partial t} = - \nabla \cdot (\rho_d \mathbf{u}),
\frac{\partial (\rho_d \mathbf{u})}{\partial t} &= - \nabla \cdot (\rho_d \mathbf{u} \mathbf{u}) -
\frac{1}{1 + q_v + q_c} ( \nabla p^\prime + \delta_{i,3}\mathbf{B} ) - \nabla \cdot \tau + \mathbf{F}
\frac{\partial (\rho_d \mathbf{u})}{\partial t} = - \nabla \cdot (\rho_d \mathbf{u} \mathbf{u}) - \frac{1}{1 + q_v + q_c} ( \nabla p^{\prime} - \delta_{i,3}\mathbf{B} ) - \nabla \cdot \boldsymbol{\tau} + \mathbf{F}_{u},
\frac{\partial (\rho_d \theta_d)}{\partial t} &= - \nabla \cdot (\rho_d \mathbf{u} \theta_d)
+ \nabla \cdot ( \rho_d \alpha_{T}\ \nabla \theta_d) + \frac{\theta_d L_v}{T_d C_{pd}} f_{cond}
\frac{\partial (\rho_d \theta_d)}{\partial t} = - \nabla \cdot (\rho_d \mathbf{u} \theta_d) + \nabla \cdot ( \rho_d \alpha_{\theta}\ \nabla \theta_d) + F_{\theta} + H_{n},
\frac{\partial (\rho_d q_v)}{\partial t} &= - \nabla \cdot (\rho_d \mathbf{u} q_vi) + \nabla \cdot (\rho_d \alpha \nabla q_v) - f_{cond}
\frac{\partial (\rho_d \boldsymbol{\phi})}{\partial t} = - \nabla \cdot (\rho_d \mathbf{u} \boldsymbol{\phi}) + \nabla \cdot ( \rho_d \alpha_{\phi}\ \nabla \boldsymbol{\phi}) + \mathbf{F}_{\phi},
\frac{\partial (\rho_d q_c)}{\partial t} &= - \nabla \cdot (\rho_d \mathbf{u} q_c) + \nabla \cdot (\rho_d \alpha \nabla q_c) + f_{cond}
\frac{\partial (\rho_d \mathbf{q_{n}})}{\partial t} = - \nabla \cdot (\rho_d \mathbf{u} \mathbf{q_{n}}) + \nabla \cdot (\rho_d \alpha_{q} \nabla \mathbf{q_{n}}) + \mathbf{F_{n}},
the non-precipitating water mixing ratio vector :math:`\mathbf{q_{n}} = \left[ q_v \;\; q_c \;\; q_i \right]` includes water vapor, :math:`q_v`, cloud water, :math:`q_c`, and cloud ice, :math:`q_i`, although some models may not include cloud ice. The source terms for moisture variables, :math:`\mathbf{F_{n}}`, and their corresponding impact on potential temperature, :math:`H_{n}` are specific to the employed model. For the Kessler microphysics scheme, these terms are detailed in :ref:`sec:Kessler Microphysics model <Microphysics>`.

Here :math:`L_v` is the latent heat of vaporization, :math:`\theta_d` is the (dry) potential temperature
:math:`\mathbf{B}` is the buoyancy force, which is defined in :ref:`sec:Buoyancy <Buoyancy>`.

The pressure perturbation is computed as

.. math::
p^\prime = p_0 \left( \frac{R_d \rho_d \theta_m}{p_0} \right)^\gamma - p_0
p^\prime = P_{00} \left( \frac{R_d \rho_d \theta_m}{P_{00}} \right)^\gamma - p_{0}
where :math:`\gamma = C_{pd} / C_{vd}` and
where :math:`\gamma = c_{p} / (c_{p} - R_{d})` and

.. math::
\theta_m = \theta_d (1 + \frac{R_v}{R_d} q_v)
Expand All @@ -67,7 +65,7 @@ Model 2: Full Moisture Including Precipitation

With this model, in addition to dry air :math:`\rho_d` and nonprecipitating water vapor :math:`\rho_v`,
assumed to be a perfect ideal gas with constant heat capacities
:math:`C_{vd}`, :math:`C_{vv}`, :math:`C_{pd}`, :math:`C_{pv}`,
:math:`c_{vd}`, :math:`c_{vv}`, :math:`c_{pd}`, :math:`C_{pv}`,
we include
non-precipitating condensates :math:`\rho_c + \rho_i`,
and precipitating condensates :math:`\rho_p = \rho_{rain} + \rho_{snow} + \rho_{graupel}`.
Expand Down Expand Up @@ -102,9 +100,9 @@ and write the EOS as
or

.. math::
p = p_0 (\frac{\Pi}{C_p^\star})^{\frac{C_p^\star}{R^\star}}
p = P_{00} (\frac{\Pi}{c_p^\star})^{\frac{c_p^\star}{R^\star}}
where :math:`p_0` is the reference pressure. and
where :math:`P_{00}` is the reference pressure. and

.. math::
\Pi = C_p^\star (\frac{p}{\alpha p_0})^\frac{R^\star}{C_p^\star}
Expand All @@ -118,23 +116,19 @@ water vapor, cloud ice, and precipitating condensates, respectively.

Governing Equations
-------------------
We assume that all species have same average speed,
Then the governing equations become
The governing equations with precipitating moisture components are

.. math::
\frac{\partial \rho_d}{\partial t} &= - \nabla \cdot (\rho_d \mathbf{u} + \mathbf{F}_\rho)
\frac{\partial \rho_d}{\partial t} = - \nabla \cdot (\rho_d \mathbf{u}),
\frac{\partial (\rho_d \mathbf{u})}{\partial t} = - \nabla \cdot (\rho_d \mathbf{u} \mathbf{u}) - \frac{1}{1 + q_v + q_c} ( \nabla p^{\prime} - \delta_{i,3}\mathbf{B} ) - \nabla \cdot \boldsymbol{\tau} + \mathbf{F}_{u},
\frac{\partial (\rho_d \mathbf{u})}{\partial t} &= - \nabla \cdot (\rho_d \mathbf{u} \mathbf{u} + \mathbf{F}_u) -
\frac{1}{1 + q_T + q_p} \nabla p^\prime - \nabla \cdot \tau + \mathbf{F} + \delta_{i,3}\mathbf{B}
\frac{\partial (\rho_d \theta_d)}{\partial t} = - \nabla \cdot (\rho_d \mathbf{u} \theta_d) + \nabla \cdot ( \rho_d \alpha_{\theta}\ \nabla \theta_d) + F_{\theta} + H_{n} + H_{p},
\frac{\partial (\rho_d \theta)}{\partial t} &= - \nabla \cdot (\rho_d \mathbf{u} \theta + F_{\theta}) + \nabla \cdot ( \rho_d \alpha_{T}\ \nabla \theta) + F_Q
\frac{\partial (\rho_d \boldsymbol{\phi})}{\partial t} = - \nabla \cdot (\rho_d \mathbf{u} \boldsymbol{\phi}) + \nabla \cdot ( \rho_d \alpha_{\phi}\ \nabla \boldsymbol{\phi}) + \mathbf{F}_{\phi},
\frac{\partial (\rho_d q_T)}{\partial t} &= - \nabla \cdot (\rho_d \mathbf{u} q_T +F_{q_{T}}) - Q
\frac{\partial (\rho_d \mathbf{q_{n}})}{\partial t} = - \nabla \cdot (\rho_d \mathbf{u} \mathbf{q_{n}}) + \nabla \cdot (\rho_d \alpha_{q} \nabla \mathbf{q_{n}}) + \mathbf{F_{n}} + \mathbf{G_{p}},
\frac{\partial (\rho_d q_p)}{\partial t} &= - \nabla \cdot (\rho_d \mathbf{u} q_p + F_{q_{p}}) + Q
\frac{\partial (\rho_d \mathbf{q_{p}})}{\partial t} = - \nabla \cdot (\rho_d \mathbf{u} \mathbf{q_{p}}) + \partial_{z} \left( \rho_d \mathbf{w_{t}} \mathbf{q_{p}} \right) + \mathbf{F_{p}}.
In this set of equations, the subgrid turbulent parameterization effects are included with fluxes
:math:`F_\rho`, :math:`F_u`, :math:`F_C`, :math:`F_{\theta}`, :math:`F_{q_{T}}`, :math:`F_{q_{r}}`.
:math:`\mathbf{F}` stands for the external force, and :math:`Q` and :math:`F_Q` represent the mass and energy transformation
of water vapor to/from water through condensation/evaporation, which is determined by the microphysics parameterization processes.
:math:`\mathbf{B}` is the buoyancy force, which is defined in :ref:`sec:Buoyancy <Buoyancy>`.
the non-precipitating water mixing ratio vector :math:`\mathbf{q_{n}} = \left[ q_v \;\; q_c \;\; q_i \right]` includes water vapor, :math:`q_v`, cloud water, :math:`q_c`, and cloud ice, :math:`q_i`, although some models may not include cloud ice; similarly, the precipitating water mixing ratio vector :math:`\mathbf{q_{p}} = \left[ q_r \;\; q_s \;\; q_g \right]` involves rain, :math:`q_r`, snow, :math:`q_s`, and graupel, :math:`q_g`, though some models may not include these terms. The source terms for moisture variables, :math:`\mathbf{F_{p}}`, :math:`\mathbf{F_{n}}`, :math:`\mathbf{G_{p}}`, and their corresponding impact on potential temperature, :math:`H_{n}` and :math:`H_{p}`, and the terminal velocity, :math:`\mathbf{w_{t}}` are specific to the employed model. For the Kessler microphysics scheme, these terms are detailed in :ref:`sec:Kessler Microphysics model <Microphysics>`.

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