Vaisala IRIS - Figure 12 Melting Level Height Detection

The height of the melting level is an important aspect to understanding what is happening
micro-physically within precipitation systems. Changes of melting level height can assist in
determining the likelihood of hail and lightning, and is related to estimating strength of
downdrafts due to phase change from ice to liquid. During winter conditions determining
the location of liquid versus ice precipitation at the surface is improved with knowledge of
the melting level, especially in mountainous terrain.
The presence of the bright band associated with the melting level must be accounted for
with quantitative interpretations of weather observations.
In IRIS and RDA software, the SRI product uses the melting level height to perform Vertical
Reflectivity Profile corrections, to apply Fall Speed corrections to radial velocity, to
distinguish between convective and non-convective precipitation, to account for the
dierent attenuation between liquid and ice, and as a membership function in the
Hydrometeor Classification function. Thus an automated determination of the melting level
height and how it varies spatially and temporally adds value to the overall weather radar
system software.
Figure 12 Melting Level Height Detection
IRIS Product and Display User Guide M211319EN-H
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