Vaisala IRIS - Figure 34 Example of 15-Tilt Volume Scan

4. In ZW Relation, select the reflectivity-water content (Z-W) relationship.
This field is desensitized if we are computing a reflectivity based product rather than a
water based product. A default value for rain is provided. For snow, reduce the
coecient to a smaller value, such as 2000, to account for the lower reflectivity of ice.
VIL can function when only one angle is in the task, but this is not recommended for
best results. If no angle in the associated task passes through the VIL layer, no VIL can
be calculated.
For a VIL layer of 5 to 10 km (3.1 to 6.2 mi), in the volume scan example in the following
figure, VIL cannot be calculated for ranges less than 5 km (3.1 mi). In the resulting
product display, black would be displayed in this region to indicate that IRIS did not
even sample the region.
0
5
10
10 20 30 40 50
44.9
34.9 26.5
18.3 13.9
11.1 9.3
7.4
6.4
5.5
4.6
3.6
2.7
1.7
0.8
Figure 34 Example of 15-tilt Volume Scan
More information
‣
LAYER: Layer Average (page 41)
‣
Display Parameters (page 27)
‣
Product Parameters (page 23)
‣
Associating Products with Tasks (page 17)
Chapter 3 – Configuring IRIS Products
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