Merge updates for NOAH-MP Interface

Docs/sphinx_doc/CouplingToNoahMP.rst

@@ -0,0 +1,99 @@
+   .. role:: cpp(code)
+      :language: c++
+
+Coupling to Noah-MP
+===================
+
+Overview
+--------
+
+The NOAH Land Surface Model (LSM) is integrated with ERF to facilitate
+interaction with the Noah-MP (Multi-Physics) land surface processes.
+
+This documentation covers key components of this interface and its
+associated data structures and routines, which are implemented in C++
+and Fortran, and provides details on initialization and management of
+data structures necessary for these processes.
+
+Files Overview
+--------------
+
+-  **Source/LandSurfaceModel/NOAH/ERF_NOAH.H**: Contains the declaration
+   of the NOAH class, which extends the NullSurf.
+
+-  **Source/LandSurfaceModel/NOAH/ERF_NOAH.cpp**: Implements the
+   initialization routine for the NOAH class.
+
+-  **Submodules/NOAH-MP/drivers/hrldas/NoahmpIO.H**: Defines the C++
+   `NoahmpIO_type` that is used to interface with Noah-MP implementations
+   following similar structure as the underlying Fortran interface
+   (https://dx.doi.org/10.5065/ew8g-yr95).
+
+-  **Submodules/NOAH-MP/drivers/hrldas/NoahmpIO.cpp**: Contains the
+   implementation of C++ routines interfacing with Fortran.
+
+-  **Submodules/NOAH-MP/drivers/hrldas/NoahmpIO_fi.F90**: Fortran module
+   responsible for managing mapping data between C++ and Fortran.
+
+NOAH Class
+----------
+
+The NOAH class serves as the handler for initializing and managing the
+data structures required for NOAH-MP operations. It inherits from the
+`NullSurf` class. This class declares private variable `NoahmpIO_type
+noahmpio`, that is passed to NoahMP routines similar to the Fortran
+interface in the Noah-MP documentation
+(https://dx.doi.org/10.5065/ew8g-yr95)
+
+NoahmpIO_type Structure
+-----------------------
+
+This structure is key for handling the input and output operations for
+NOAH-MP through C++ and Fortran interoperation. Contains various
+variables for domain, memory, and tile configuration. Also, contains
+arrays for geographic variables. At present this type exposes only a
+select set of variables. More variables should be exposed as needed by
+applications in ERF. The process of adding new variables is as follows:
+
+#. In **Submodules/NOAH-MP/drivers/hrldas/NoahmpIO.H** add pointers to
+   the desired variable and set their initialization for
+   `NoahmpIO_type_fi` similar to implementation of `WSLAKEXY` and
+   `XLAT`.
+
+#. In **Submodules/NOAH-MP/drivers/hrldas/NoahmpIO.H** declare objects
+   for Fortran-style multidimensional arrays for the same variables in
+   `NoahmpIO_type` similar to implemnation of `NoahArray2D<double> XLAT`
+   and `NoahArray2D<double> WSLAKEXY`.
+
+#. In **Submodules/NOAH-MP/drivers/hrldas/NoahmpIO.cpp** cast the
+   pointers from `NoahmpIO_type_fi` to multidimensional arrays in
+   `NoahmpIO_type` within the implementation of `void
+   NoahmpIOVarInitDefault(NoahmpIO_type* noahmpio)`.
+
+Fortran Interoperability
+------------------------
+
+The connection between C++ and Fortran is managed through `NoahmpIO_fi`.
+This module contains a mirroring of the C++ structure for NOAH-MP
+input-output operations.
+
+The following functions are used to operate on the `NoahmpIO_type` and
+interface with their respective Fortran implementations:
+
+-  `void NoahmpIOVarInitDefault(NoahmpIO_type* noahmpio)`: Initializes
+   default variables of `NoahmpIO_type`. Create C pointer for Fortran
+   data.
+
+-  `void NoahmpInitMain(NoahmpIO_type* noahmpio)`: Main initialization
+   function for the NOAH-MP operations in C++.
+
+Usage
+-----
+
+To use the NOAH class and associated functions, ensure the correct
+initialization sequence is followed within the simulation setup. The
+interplay between C++ and Fortran necessitates careful memory and data
+handling, which is crucial for ensuring performance and correctness in
+simulations. The interface is designed to mimic the Fortran interface
+from documentation(https://dx.doi.org/10.5065/ew8g-yr95), therefore
+similar practices should be followed.

Docs/sphinx_doc/index.rst

@@ -88,6 +88,7 @@ In addition to this documentation, there is API documentation for ERF generated
 
    CouplingToAMRWind.rst
    CouplingToWW3.rst
+   CouplingToNoahMP.rst
 
 .. toctree::
    :caption: ERF vs WRF

Source/LandSurfaceModel/NOAH/ERF_NOAH.H

@@ -31,11 +31,10 @@ public:
           const amrex::Geometry& geom,
           const amrex::Real& dt) override;
 
-
 private:
 
-   // C++ variable for NoahmpIO struct
-   NoahmpIO_struct noahmpio;
+   // C++ variable for NoahmpIO type
+   NoahmpIO_type noahmpio;
 
 };
 #endif

Source/LandSurfaceModel/NOAH/ERF_NOAH.cpp

@@ -20,7 +20,29 @@ NOAH::Init (const MultiFab& cons_in,
      * noahmpio.xend = 4;
      * noahmpio.ystart = 1;
      * noahmpio.yend = 2;
+     * noahmpio.nsoil = 1;
+     * noahmpio.nsnow = 3;
      *
+     * noahmpio.ids = 1;
+     * noahmpio.ide = 1;
+     * noahmpio.ims = 1;
+     * noahmpio.ime = 1;
+     * noahmpio.its = 1;
+     * noahmpio.ite = 1;
+     *
+     * noahmpio.jds = 1;
+     * noahmpio.jde = 1;
+     * noahmpio.jms = 1;
+     * noahmpio.jme = 1;
+     * noahmpio.jts = 1;
+     * noahmpio.jte = 1;
+     *
+     * noahmpio.kds = 1;
+     * noahmpio.kde = 1;
+     * noahmpio.kms = 1;
+     * noahmpio.kme = 1;
+     * noahmpio.kts = 1;
+     * noahmpio.kte = 1;
      */
 
     NoahmpIOVarInitDefault(&noahmpio);