SOLARZAZ

Description

SOLARZAZ calculates the solar zenith angle and azimuth for a user-specified date, time-of-day, and Earth location.

Parameters

Name	Type	Length	Value range
Date*	Integer	3 - 3
Time of Day*	Integer	2 - 3
Latitude*	Float	1 - 1	-90.0 - 90.0
Longitude*	Float	1 - 1	-180.0 - 180.0
Report	String	0 - 192	See parameter description

* Required parameter

Parameter descriptions

Date

Specifies the date for which the solar zenith and azimuth angles will be computed.

Time of Day

Specifies the time of day for which the solar zenith and azimuth angles will be computed.

If not specified, seconds default to 0.

Latitude

Specifies the latitude for which the solar zenith and azimuth angles will be computed.

Longitude

Specifies the longitude for which the solar zenith and azimuth angles will be computed.

Report

Specifies where to direct the generated report.

Available options are:

• LOG: generates a report on the terminal (default)
• <modulename.RPT>: appends a report to the module's RPT file
• DISK: generates a report on file "IMPRPT.LST"

Details

SOLARZAZ is a utility that facilitates the use of the atmospheric correction system. It outputs the solar zenith and solar azimuth angles for a specified date and time of day, and latitude and longitude coordinates.

The solar zenith angle is the angle between the ground-to-zenith and ground-to-sun directions and can vary from 0 to 180, with 0 being when the sun is directly above the observed ground position.

The solar azimuth angle is the angle between the ground-to-sun and ground-to-North directions, positive clockwise from ground-to-North. The solar azimuth is 0 if the sun is to the North of the observed ground position, 90, if the sun is to the East of the observed ground position, and so on.

Acknowledgements

PCI Geomatics received financial support from the Canadian Space Agency/L'Agence Spatiale Canadienne through the Earth Observation Application Development Program (EOADP) for the development of this software, under contract 9F028-0-4914/09.