Vaisala IRIS, User Manual

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2. For DSP Data and Data:Display , SRI products require
T
and
Z
values as input.
Make sure that both are recorded in your task.
For
Data:Display you can select if you want to see the result in
dBZ
or in intensity
mm/h (
dBZ:R
) .
In
dBZc
and
dBZc:R
, the
c
refers to the included corrections for attenuation, beam
blockage, and similar as configured for the task. Even if you display mm/h, the
convection threshold is given in
dBZ
.
For radar systems that import data, the SRI product can also run without
T
(Total
power) data. In a such a mode, the "lowest clutter-free bin" feature is unavailable, but
the product can still be run.
3. In Ref Hgt , select the reference height to which the reflectivity profile of the SRI
product is calculated.
• Fixed
Type the height (km). This is height above 0 reference.
• Map
IRIS retrieves the height information from a terrain map file. See Format of Terrain
Map File (page 81) .
4. In Max Height , set the maximum height where the "lowest clutter free bin" is searched
for.
If there are no clutter free bins below this height, no correction is performed.
You must set a reasonable level, such as below 5 km (3.1 mi). Note that at far ranges,
when the lowest beam is above the
Max Height , the lowest beam is used.
5. To use a profile in the correction, enable Use profile .
This is an easy way to switch the correction temporarily off. You do not need to
change other places of your production chain.
6. In 0C Height , select the height of the melting level with one of the following options:
• Ingest
The height of the melting level is extracted from the Setup on the radar computer at
the time of the measurement. (This is important if you process archived data.)
All the other gradient numbers are pulled from the current setup on the product
computer.
If you have a network of radars and make the products centrally in one IRIS analysis,
you can set an individual melting level for each radar at the
Setup of the IRIS radar
and use the Ingest setting here.
• Setup
IRIS uses the melting level heights given in Setup > General Setup on the product
computer.
If you want to use the same melting level for all radars and keep adjusting just one
value, use the
Setup option here.
• Type-In
When you are testing the product interactively, use Type-In to type the value.
IRIS Product and Display User Guide M211319EN-H
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