Diffuse irradiance on an inclined plane Di [W/m],

where:

if plane is in shade (e.g. ?iexp < 0 and ho > 0); FxFiYN)

P{yN) = + (sinY/v - Ywcosy/v - JCsin ()) 0.252271

if plane is sunlit under clear sky: ifho>0.\rad:

Fx = F(7/v)(l - Kb) Л- Kb sin&exp/sinfio ifho<Q.lrad: Fx = F{yN){l-Kb)+KbsmyNCOBALN/iO-i -O.OOS/iq)

LN =Ao~An

Aln =

Aln = - 2л

/-я<л;д, < л

/(Y/v) = ( (Y/v) + (siajN -Ywcosyw - rtsin )) (0.00263 -0.71 гА ;, -0.688.3A:2)

= Bh/Goh ri{yN) = U+cosyN)/2

Diffuse ground reflected irradiance on an inclined plane R, [W/m].

where:

g(Yw) = (l-cos7w)/2 Gh=Bh + Dh

with Gb in [W/m

Symbols.

Position of the grid cell (solar plane):

Ф geographical latitude [rad] Z elevation above sea level [m] slope angle [rad]

An aspect (orientation, azimuth) - angle between the projection of the normal on the horizontal plane and east [rad]

ф relative geographical latitude of an inclined plane [rad]

relative geographical longitude [rad]

Parameters of the surface (plane):

mean ground albedo Date-related parameters: day day number 1-365 (366) j Julian day number expressed as a day angle [rad] T time of computation [decimal hours/rad]

time of sunrise and sunset over the local horizon Tpr i time of sunrise and sunset over the inclined grid cell (plane) solar declination [rad]

correction of the variation of sun-earth distance from its mean value Solar position:

fto solar altitude - an angle between sun and horizon [rad]

Aq solar azimuth - an angle between sun and meridian measured from east [rad]

angle between the vertical plane containing the normal to the surface and vertical plane passing through the center of the solar disc [radi

solar incidence angle - an angle between sun and the (inclined) plane [rad] Solar radiation: /о solar const= 1367 W/m

Go extraterrestrial irradiance on a plane perpendicular to the solar beam [W/m] G/, G/, = S/, +Df,- global solar irradiance on a horizontal plane [W/m] Gj Gi - Bi \ Di f Ri - global solar irradiance on an inclined plane [W/m]

beam irradiance on a horizontal plane

beam irradiance on an inclined plane

diffuse irradiance on an horizontal plane Di diffuse irradiance on an inclined plane [W/m] Ri diffuse ground reflected irradiance on an inclined plane [W/m] Parameters of the atmosphere:

correction of station elevation [-] Tlk Linke turbidity factor [-]

Tl corrected Linke turbidity factor ( Ti = 0.8662 Tik), see Kasten, 1996)

m relative optical air mass [-]

5 (m) Rayleigh optical thickness [-]

Parameters of the radiation transmission:

F(i{h<f) diffuse solar elevation function

1n{Tix) diffuse transmission function

F{n) function accounting for the diffuse sky irradiance distribution

proportion between beam irradiance and extraterrestrial solar irradiance on a horizontal plane

fraction of the sky dome viewed by an inclined plane [-] fraction of the ground viewed by an inclined plane [-]

Appendix C

UMN/MapServer sample configuration

This appendix section contains a sample UMN/MapServer definition file and a sample UMN/MapServer HTML template. The example contains read routines for vector data (SHAPE format) and raster data (GeoTIFF and GRASS LOCATION). Please refer to Section 13.4 for further details.

C.1. UMN/MapServer DEFINITION FILE

This sample UMN/MapServer definition file defines the map, projection and coordinates settings.

# UMN/MapServer / GRASS:

# this file contains the map definitions

# This program is Free Software under the GNU GPL (>=2).

# Markus Neteler 2001

# You need:

# * .grassrc5 stored in $DOCUMENT ROOT

# (e.g. /usr/local/httpd/htdocs/ ),

# which may be the HOME of the apache user,

# containing the entries:

# GISDBASE: /usr/local/share/grassdata

# LOCATION NAME: spearfish

# MAPSET: PERMANENT

# * a tmp directory: /tmp/mapserver (with Apache Alias)

# * a start file with this URL to the cgi-bin inside:

# http: localhost/cgi-bin/mapserv?map=\

# /usr/local/httpd/map-script/mapserver. map

# * the spearfish.html defining the map/html template

# * this mapserver.map containing the map definitions