LI-COR LI7200RS, Инструкция по эксплуатации

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Section 3. Operation
For example, you can use three months of data to calculate a spectral assessment,
and then use this spectral assessment that is summarized in a short text file, to cor-
rect fluxes calculated from data collected after those three months, if the system con-
figuration didn’t change to such an extent that the spectral assessment is no longer
representative. Similar considerations apply to the planar fit and the timelag optim-
ization procedures. Refer to EddyPro documentation for more details on when and
how to use these three advanced procedures.
The additional configuration files are created by EddyPro (3.0 and above), when
used in the standard desktop mode. If you have been running your EC system (the
EC sytem in which you intend to use the SmartFlux System or SmartFlux 2 Sys-
tem) for some time, you may have already created one or more of these files, or you
may have a .ghg dataset suitable for creating them, if the corresponding imple-
mentation is deemed necessary to calculate accurate fluxes (again, refer to EddyPro
documentation to learn more about when it is suggested to use these options). If
you do not have previously-collected .ghg files, then you will need to run the sys-
tem for a suitable amount of time (for example using SmartFlux in Express mode),
then use EddyPro in desktop mode to create the additional configuration files of
your interest, and then provide them to the SmartFlux System or SmartFlux 2 Sys-
tem as explained below.
EddyPro Advanced Setting Recommended Dataset
Planar Fit Settings 2 weeks minimum; < 2 months
Time Lag Optimization 1 to 2 months or more
Spectral Corrections, Assessment of high
frequency attenuation 1 month or more
Table 3-4 . Recommended dataset durations for Advanced settings.
Thus, assuming that you have a sufficiently long .ghg dataset ( Table 3-4 above), the
procedure to correctly configure the SmartFlux System or SmartFlux 2 System to
use planar-fit, in-situ spectral corrections or timelag optimization is illustrated here,
using the in-situ spectral corrections as an example. Analogous procedures shall be
followed for the planar-fit or the timelag optimization.
1 Open EddyPro (5.0 or above recommended) in normal desktop mode and complete the
Project
Creation
and
Basic Settings
pages as usual (refer to EddyPro documentation if needed).
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