% Define whether this is a chapter/section/subsection in the master document

\documentclass[10pt,letterpaper, final]{report}
\usepackage{../preamble/myWEPS}

\begin{document}

Choosing a location within WEPS defines the physical location of the field to be simulated.
This location information is then normally used within WEPS to automatically select the representative climate stations
(Cligen and Windgen) to be used for the simulation.
There are multiple methods available to select the site location (or representative approximate site location).
Location information is entered through the upper right panel of the main interface screen, labeled Location (\cref{fig:Loc_Info_panel}).

By default, the Cligen and Windgen stations nearest to the latitude and longitude coordinates
displayed in the \textbf{Latitude/Longitude} fields will automatically be determined
and made available in a sorted list
with the nearest stations selected by default.\footnote{
Note that there are several station selection "modes" available for Cligen and Windgen
as well as a special "NRCS" mode that determines which selection method is used based upon specific criteria.
All of this is configurable within WEPS and can be specified via the Config Panel settings (if appropriately configured to do so).
}
The \textbf{Elevation} field will automatically be populated by default with the elevation of the selected Cligen station.

If configured, only the nearest station may be selected by default
or if the polygon regions approach is used, then the assigned station for that polygon region is specified.
Also, if configured, and the site is located within the "interpolated" polygon region,
then an interpolated station will be created and used.\footnote{
Interpolation currently only implemented for Windgen stations.
PRISM adjustment of the selected Cligen station is used instead of station interpolation within the conterminous U.S.
}
Some or all of the station selection options can be made available and selected for use via the WEPS configuration settings and accessible via the Config Panel.
A special "NRCS" setting is also available that determines the specific criteria for the selection options applied
under all siting scenarios for both Cligen and Windgen station determinations.

Notice that the \textbf{Cligen} and \textbf{Windgen} fields display not only the station name,
but also the distance from the specified lat/long location above.
By clicking on the down arrow \img{images/icons/down_arrow.png} to the right of the individual station fields,
the user can override the default nearest station selection if desired.
The radius range distance used for populating the nearest station lists is also displayed immediately above the weather station fields.
There are other options available that can be used to determine the stations selected.
They are accessible via the \img{images/Interface_Ref/ellipses.jpg} button left of the weather station fields.
This button does not display if only one weather station selection option has been specified in the WEPS configuration settings.
These options are discussed in more detail later in this section.\footnote{
Note that the default weather station selection behavior can be modified and is in fact configured differently for various WEPS versions,
including the NRCS WEPS releases.
}

Likewise, there are configuration options that control whether the \textbf{Country}, \textbf{State} and \textbf{County} fields are displayed,
or the \textbf{lat/long} fields and even the \textbf{Map Viewer} button (labeled either "Please Select Field Location" or "Field Location Selected").
Thus, the \textbf{Location} panel will often appear somewhat differently than the one shown in \cref{fig:Loc_Info_panel}
for those alternatively configured WEPS versions.
\begin{figure}[H]
	\centering
	\includegraphics[scale=0.76]{images/Interface_Ref/Loc_Info_panel_Please_Select_Field_Loc.jpg}
	\caption{Location information panel on main WEPS screen.}
	\label{fig:Loc_Info_panel}
\end{figure}
\subsection{Country/State/County Site Selection Method} \label{subsec:Country/State/County_Site_Selection_Method}
This method provides an approximation of the site location.
Select the \textbf{Country}, if configured to display that input field\footnote
{
Note that the NRCS configured version of WEPS
does not display the \textbf{Country} field and assumes the country is the United States.
To display this field or not can be specified in the WEPS configuration settings.
},
then the \textbf{State} (or \textbf{Province}, etc.) and finally the \textbf{County} (or \textbf{Parish}, etc.)
of interest from their respective drop-down lists
by clicking the down arrow \img{images/icons/down_arrow.png}
to the right of the individual fields.
The centroid\footnote
{
We use the term “centroid” in this document, but if the county polygon is shaped such that the true centroid is located outside the county (polygon) region,
we adjust the coordinates such that the lat/long displayed will always fall within the county border.
}
latitude and longitude coordinates of the county will automatically be displayed.
\subsection{Lat/Long Site Selection Method} \label{subsec:Lat/Long_Site_Selection_Method}
As an alternative, the Latitude and Longitude of the site location can also be directly entered,
which will automatically display the country(if configured for display), state and county
in which the coordinates reside and then select
the nearest Cligen and Windgen stations to those latitude/longitude coordinates.
Note that the hemisphere is displayed in the lat/long fields.
The “N” (northern) and “E” (eastern) hemispheres are represented as positive values
and the “S” (southern) and “W” (western) hemispheres are represented as negative values
when a user clicks in those fields to edit them.
The default hemispheres are the Northern and Western hemispheres for the United States.
If the Southern hemisphere is desired,
the user should select Cligen stations and management files with appropriate operation dates for this hemisphere. 
\subsection{Map Viewer Site Selection Method} \label{subsec:Map_Viewer_Site_Selection_Method}
Another alternative method to choosing a site location is by using the \textbf{Map Viewer}
(button labeled either "Please Select Field Location" or "Field Location Selected"),
if configured to display the \textbf{Map Viewer} button.
Clicking on the Map Viewer button (as shown in \cref{fig:Loc_Info_panel})
will bring up a window containing a map of the world
zoomed into the region centered about the currently listed lat/long coordinates,
which is highlighted as a red cross (+ sign) on the map (\cref{fig:Map_Viewer_window}).
The current lat/long coordinates of the red cross are displayed in the upper left corner of the map screen.
\begin{figure}[H]
	\centering
	\includegraphics[scale=0.67]{images/Interface_Ref/Map_Viewer_window.jpg}
	\caption{Default WEPS Map Viewer displayed with lat/long coordinates specified in the Location panel.}
	\label{fig:Map_Viewer_window}
\end{figure}
The user can select any location on the map to change the lat/long values in the \textbf{Location} panel on the main WEPS interface screen.
They can move the mouse cursor to the desired site location within the map
(current mouse cursor lat/long coordinates are displayed in the lower right side of the screen
and are continuously updated when the mouse cursor is moved).
The user can set the red cross (+ sign) by clicking the left mouse button once.
Double clicking the left mouse button will set the location at the cursor
and automatically close the \textbf{Map Viewer} window.
This will then execute the same function as  clicking on the \textbf{Map Viewer} window's "Done" button, i.e.
populate the \textbf{Location} panel Lat/Long fields, then update
the Country, State and County fields as well as re-selecting the default Cligen and Windgen stations, if necessary.

The user can move the map left, right, up and down by selecting the appropriate directional controls
(4 white arrows surrounded by a blue background) at the top left of the screen.
By clicking the appropriate arrows, the user can move the map in the specified direction in the window.
Likewise, the user can zoom the map in or out by selecting the “+/-“ controls (+/- symbols surrounded by a blue background)
that are located directly beneath the directional controls.
The user may also perform these functions directly with the mouse and mouse cursor.
By selecting a location within the map using the mouse cursor.
By pressing and holding the right mouse button down, the user can move (drag) the map left, right, up or down within the window.
By clicking the left mouse button with the cursor in the map and then scrolling the mouse wheel, the user can zoom the map in and out on the screen.
The currently selected lat/long coordinates are displayed in the upper left corner of the window
and the Country, State and County, including the Crop Management Zone (CMZ) the lat/long coordinates reside in are also displayed. 

\hl{Move the following paragraph to a new section to be created called "Additional Map Viewer Features", or something along those lines.}

Clicking the check boxes at the left side of the \textbf{Map Viewer} window will enable (display)
various GIS (Graphical Information System) layers on the map (\cref{fig:Map_Viewer_window}).
Map layers currently enabled by default are:
a) World (country) borders outline; b) U.S. states (borders) outline;
c) U.S. counties; d) (satellite) Imagery ArcGis; and e) the Current Location
(identified by a red cross (+ sign) on the map) as listed in the Location panel on the main WEPS screen.
Additional useful map layers available include:
a) Cligen station names and locations;
b) Windgen station names and locations;
c) (nearest) Cligen station boundaries;
d) NRCS CMZ (Crop Management Zone) regions;
e) Windgen interpolation \& polygon regions;
f) Windgen triangulation lines (used for displaying station interpolation regions);
g) Streets overlay ArcGIS (street map), etc.
Additional layers are also available primarily for debugging/testing purposes and other WEPS builds provide access to some of them by default.

\subsection{Weather Station Selection Methods} \label{subsec:Weather_Station_Selection_Methods}
As mentioned previously,
WEPS can be configured to automatically select both Cligen and Windgen stations differently than the default method(s) specified above.
All methods will be described here, including the NRCS method (last method listed),
which employs several of the other methods, depending upon where the lat/long location resides.
The options made available and the default method to use are configurable and can be accessible via the Config Panel for both Windgen and Cligen.
Here are the current list of all options as displayed in the Config Panel for station selection (\cref{fig:WEPS_Station_Selection_Options}).
The "Windgen Modes" and "Cligen Modes" screenshot sections came from the "Windgen" and "Cligen" tabs respectively of the Config Panel.
\hl{Include a reference to the Config Panel screen here after we add that section to the User's Manual.}

\begin{figure}[H]
	\centering
		\subcaptionbox{Windgen Modes}{\includegraphics[width=0.40\textwidth,scale=3.0]{images/Interface_Ref/Windgen_Modes.jpg}}%
	\hfill
		\subcaptionbox{Cligen Modes}{\includegraphics[width=0.40\textwidth,scale=3.0]{images/Interface_Ref/Cligen_Modes.jpg}}%
	\caption{WEPS Config Panel Windgen and Cligen Station Selection Modes.}
	\label{fig:WEPS_Station_Selection_Options}
\end{figure}

The station selection methods made available for the current instantiation of WEPS are the checkmarked option \textbf{Modes}
displayed in \cref{fig:WEPS_Station_Selection_Options}
with the default mode specified in the \textbf{default mode} field.
The available options and default settings displayed in the Config Panel
can be individually configured so some may be set "readonly" or "hidden".
Therefore, specific WEPS build configurations may appear differently than shown in \cref{fig:WEPS_Station_Selection_Options}.

The weather station inputs on the main WEPS screen with the \cref{fig:WEPS_Station_Selection_Options} settings displayed
will appear like a) below in \cref{fig:Example_Weather_Station_Inputs_Selections}.
If there are multiple station selection modes specified in the Config Panel for either weather station,
there will appear an additional \img{images/Interface_Ref/ellipses.jpg} button next to the dropdown choice list arrow.
If the \img{images/Interface_Ref/ellipses.jpg} button to the left of the Windgen station field is selected (highlighted) as shown in (a) below,
it will display the popup window as shown in (b) within \cref{fig:Example_Weather_Station_Inputs_Selections}.
This window displays the available Windgen station selection options with the default mode currently specified by the solid filled radio button.
The user can change that selection here for this instance of WEPS, if desired. 

%\ref{subfig:subfig:Weather_Station_Selection_Inputs}

\begin{figure}[H]
	\qquad
		\subcaptionbox{Weather Station Selection Input Fields}{\includegraphics[width=0.40\linewidth,scale=3.0]{images/Interface_Ref/Weather_Stations_display.jpg}}%
	\qquad\qquad\qquad
		\subcaptionbox{Windgen Selection Mode Choices}{\includegraphics[width=0.40\linewidth,scale=3.0]{images/Interface_Ref/Windgen_Mode_choices.jpg}}%
		\caption{Example Weather Station Inputs/Selections.}
	\label{fig:Example_Weather_Station_Inputs_Selections}
\end{figure}
Here is the list of weather station selection modes. Those used for Cligen and/or Windgen are specified for each selection mode listed.
\begin{itemize}
\item{\textbf{Station Choice list}} - This is the default method and has been explained above.
Briefly, a list of stations within a specified radius
(note "Radius" fields in \cref{fig:WEPS_Station_Selection_Options})
of the lat/long location is determined and sorted by distance from the lat/long location.
The nearest station in the list is displayed as the default choice, but the user has the option of overriding that selection, if desired.
\end{itemize}

\begin{itemize}
\item{\textbf{Nearest Station}} - This method selects and displays only the nearest station to the lat/long location specified.
No option is available to override this selection.
\end{itemize}

\begin{itemize}
\item{\textbf{File}} - This method allows the user to specify a previously generated weather file to use (in the Cligen or Windgen generator output file format)
rather than having the weather generators create them automatically prior to the WEPS simulation being executed.
This option is useful for developers and researchers if they need to use field weather data for research needs, etc.
This option is not normally selected for use in typical WEPS usage.
\end{itemize}

\begin{itemize}
\item{\textbf{GIS}} - This option allows GIS (Graphical Information System) map "shape" files consisting of polygon maps with stations assigned to the polygons to be used.\footnote{
The current version of WebStart WEPS no longer has any polygons defined for Cligen.
We are now applying the 4km grid PRISM adjustments by default in the conterminous U.S. to the Cligen monthly and yearly average temperatures and precipitation values,
which provides improved representative station data for the Western U.S. where we previously employed the polygon mapping approach for Cligen.}
If the lat/long location resides within a polygon, the assigned station is selected and displayed.
If the lat/long location does not reside within a polygon region, then the weather station field will display “None Selected”,
necessitating the user to manually make the choice, if no other options are made available.
The user will not be allowed to make a WEPS run until both weather stations, Cligen and Windgen, are selected.
\end{itemize}

\begin{itemize}
\item{\textbf{Interpolated}} - This option only applies to Windgen stations at this time.
Based upon a specific Windgen interpolation polygon map and a corresponding “reflected” Windgen stations map,
if the lat/long location falls within an “interpolated region” polygon,
then the Windgen record is interpolated from data within three nearby Windgen stations.
The lat/long location is used for the “interpolated” station’s location.
Note that since Windgen generated data is dependent upon the statistical parameters in the station record,
having an interpolated station that is even slightly different,
e.g. even a few feet from another location will give a completely different sequence of weather (wind) data,
even though, statistically, the two interpolated stations would be essentially the same.
Thus, care must be taken when selecting the use of the “interpolated” mode alone. (See NRCS mode for how this issue is addressed there.)
\end{itemize}

\begin{itemize}
\item{\textbf{NRCS}} - This option was developed for use by NRCS and is the default,
and only option, specified for “NRCS configured specific versions of WEPS.
It is also the recommended mode for most other WEPS users to use in the United States as well.
The NRCS mode uniquely combines several of the above listed individual options.
Note that this mode uses the list of NRCS Windgen stations for interpolation purposes,
even if the entire list of available Windgen stations has been selected for use,
e.g. like most alternative WEPS configurations available in the public release are configured.
Here is the decision tree that defines the “NRCS” Windgen station selection when the "NRCS mode" is specified:

\begin{enumerate}
\item{For Windgen only, if the lat/long location is within an “interpolated” polygon, then an “interpolated” Windgen station is created and used.
In this case, the lat/long used for interpolation is always the “centroid” lat/long for the specified county,
which may or may not be the lat/long specified on the main WEPS Location panel.
This guarantees that the NRCS user will always get the same sequence of generated wind data in that county
because it will produce the same “interpolated” Windgen record for all locations within the county.}

Due to sometimes big differences in Windgen station data and the relatively large distances between stations (at least compared to Cligen stations),
it was deemed beneficial to use interpolation rather than the “nearest station” approach
and have potentially very large differences in generated wind data occur across those nearest station boundaries.
Most of the eastern half of the U.S. is currently contained in the “interpolated” polygon region (see \cref{fig:Windgen_Interpolation_polygon}).
These Windgen interpolated polygon region(s) are selectable for viewing within the \textbf{Map Viewer} (\cref{fig:Map_Viewer_window}).
\begin{figure}[H]
%	\hspace*{0.5cm}
	\centering
	\centerline{\includegraphics[scale=1.1]{images/Interface_Ref/Windgen_Interpolation_polygon.jpg}}%
	\caption{Windgen Interpolation Polgyon region as displayed within the WEPS Map Viewer.}
	\label{fig:Windgen_Interpolation_polygon}
\end{figure}
\item{If the lat/long falls within a Cligen or Windgen polygon region, it will use the assigned station for that polygon.}

Most of the Cligen\footnote{
The current version of WebStart WEPS no longer has any polygons defined for Cligen.
We are now applying the 4km grid PRISM adjustments by default in the conterminous U.S. to the Cligen monthly and yearly average temperatures and precipitation values,
which provides improved representative station data for the Western U.S. where we previously employed the polygon mapping approach for Cligen.}
and Windgen polygons have been created by NRCS for use in the western U.S.
due to mountains separating neighboring valleys, large elevation differences between nearby weather stations, etc.
not being conducive to allowing the nearest station or interpolation selection methods to work well in these regions.
These polygon regions are selectable layers for viewing within the \textbf{Map Viewer} (\cref{fig:Map_Viewer_window}).

\item{If the lat/long location does not fall within either an “interpolated” polygon region (Windgen only) or a Windgen/Cligen polygon region,
then the nearest station is automatically selected with the user having the option to override that selection from a sorted list of other nearby weather stations.}
\end{enumerate}
\end{itemize}

\hl{Add additional info on how the "PRISM adjustment" is applied to Cligen records and where it can be changed within WebStart WEPS.}
\end{document}