Changes between Version 8 and Version 9 of doc/tec/topography

Timestamp:

Jun 6, 2017 2:06:48 PM (8 years ago)

Author:

suehring

Comment:

--

doc/tec/topography

@@ -209 +209 @@
 == Surface-bounded code ==
 
-
-
+To execute surface-bounded code, a new Fortran data-structure {{{surf_type}}} is introduced, encompassing all required surface attributes. 
+Arrays belonging to these data-structure are allocated for the exact number of surface elements on a local processor, and loops can run on the exact number of surface elements without any need of IF-ELSE clauses. 
+Following example shows the general structure of the data-structure:
+
+{{{
+#!Latex
+\begin{verbatim}
+TYPE surf_type
+    INTEGER(iwp), DIMENSION(:), ALLOCATABLE ::  I, j, k
+    REAL(wp), DIMENSION(:), ALLOCATABLE ::  shf
+    . 
+    . 
+    .
+END TYPE surf_type 
+\end{verbatim}
+}}}
+
+Using this data structure approach, new arrays for different surface types are defined: 
+{{{
+#!Latex
+\begin{verbatim}
+   TYPE (surf_type), DIMENSION(0:2) :: surf_def_h
+   TYPE (surf_type), DIMENSION(0:3) :: surf_def_v
+   TYPE (surf_type)                 :: surf_lsm_h
+   TYPE (surf_type), DIMENSION(0:3) :: surf_lsm_v
+   TYPE (surf_type)                 :: surf_usm_h
+   TYPE (surf_type), DIMENSION(0:3) :: surf_usm_v
+\end{verbatim}
+}}}
+
+The term ''def'', ''lsm'', ''usm'' indicates the type of surface, i.e. default-type, natural-type, or urban-type, respectively, while the term at the end indicates either horizontal  ''h'' or vertical surfaces ''v''.  For the different kinds of surfaces, partly different code is executed. \\
+
+For all the different surface types, MOST (see ...) is applied to model surface fluxes of momentum. 
+For default-type surfaces, surface fluxes of latent and sensible heat as well as scalars are either prescribed or model by MOST.
+In contrast, for natural- and urban-type surfaces, an energy-balance solver is applied in order to model surface fluxes of sensible and latent heat.  \\
+
+Further, in addition to the different types of surfaces, surface elements are further distinguished according to its orientation: \\
+''surf_X_h(0)'' encompass all horizontally upward-facing surfaces of its respective type, \\
+''surf_X_h(1)'' encompass all horizontally downward-facing surfaces of its respective type, \\
+''surf_X_h(0)'' encompass the model top grid points. \\
+
+Please note, downward-facing (and model top) surfaces belong always to the default type at the moment.  
+
+''surf_X_v(0)'' encompass all vertically northward-facing surfaces of its respective type, \\
+''surf_X_v(1)'' encompass all vertically southward-facing surfaces of its respective type, \\
+''surf_X_v(2)'' encompass all vertically eastward-facing surfaces of its respective type, \\
+''surf_X_v(3)'' encompass all vertically westward-facing surfaces of its respective type. \\
+
+'''Remark:''' At the moment it is only possible to have one surface type at once, .e.g. only natural surfaces treated by the land-surface model. 
+In the future, however, different surface types can co-exist next to each other, i.e. it is possible to define areas where the urban-surface model and areas where the land-surface model is executed at the same time. 
+