LI-COR LI7200RS, Инструкция по эксплуатации

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Section 3. Operation
Roughness length:
In the logarithmic wind profile, the roughness length is the
height at which wind speed is zero (indicated by z
0
). It provides an estimate of the
average roughness elements of the surface. With vegetated surfaces, because the
vegetation itself provides a certain roughness, the logarithmic wind profile goes to
zero at a height equal to the displacement height plus the roughness length. If not
entered explicitly, EddyPro computes roughness length as:
3-2 z
0
= 0.15 x canopy height
Use SmartFlux GPS Coordinates ( mandatory ):
Uses GPS location from the
SmartFlux 2 System for the station location.
Note: If you are testing the SmartFlux 2 System in a building, the GPS signals
may be too weak for the system to find the location, and the software will not
show a location. The system will get this information whenever it gets adequate
GPS signals.
GPS format (WGS84):
Latitude and longitude coordinates are automatically detec-
ted by the SmartFlux 2 System or they can be entered manually.
Format Description Example
DDD MM SS.SSS Degrees, minutes and seconds with North,
South, East, or West suffix 12°20’44” N,
98°45’55” W
DDD MM.MMM Degrees and decimal minutes with North,
South, East, or West suffix 12°20.736’ N,
98°45.924’ W
Decimal Degrees Decimal degrees with negative numbers
for South and West 12. 3456, -98.7654
Latitude (mandatory if "Use GPS Coordinates" is not selected) :
Site latitude.
Longitude ( mandatory if "Use GPS Coordinates" is not selected ):
Site longitude.
Altitude (mandatory if "Use GPS Coordinates" is not selected) :
Altitude (in meters)
of the research site.
Entering Anemometer Information
The
Sonic Anemometer
tab allows you to enter information about the sonic anem-
ometer, including the manufacturer and model, data output format, offset from
true north, and height. Some of the available options (e.g., North Alignment) will
3-22 LI-7200RS Enclosed CO₂/H₂O Analyzer