Kipp & Zonen LAS, Инструкция по эксплуатации

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3. Effective height LAS / XLAS
The accuracy of the fluxes of sensible heat and evaporation depends strongly on the mean height of
the
LAS above the surface. In case the area is completely flat the average beam height can be easily
derived from the Transmitter height and the Receiver height. In case the area is very complex (such
as shown in Figure 37) it becomes more difficult to determine the
effective height of the LAS / XLAS .
The EVATION software has a special tool that helps the user to determine the effective height
(“
Effective height calculator ”). The “effective height calculator” needs the following input data:
transmitter installation height, receiver installation height, the elevation of the transmitter and receiver
site, and the elevation plus position of a number of points along the optical path of the
LAS (i.e.
EVATION needs a cross section of the LAS setup over the area). By entering this information in the
“Effective height calculator” the software gives you the effective height of the LAS , which finally will be
used in the actual data processing to fluxes. An example is shown in Table 6 and Figure 37. You can
use the table below for collecting a number of points to determine the effective height of your
LAS
setup.
Distance to
reference
[m]
Elevation
[m]
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26