WMOD00580

• Project Name: Sierra Cooperative Pilot Project
• Title: Supercooled Liquid Water and Ice Crystal Distributions Within Sierra Nevada Winter Storms
• Date: 11/11/1983
• Weather Modification - Doc Type: Report

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1878

JOURNAL OF CLIMATE AND APPLIED METEOROLOGY

VOLUME 22

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seeding. Likewise, when a cloud has a greater ICC it
is less likely to respond to seeding, or at least respond
obserVably (see Cooper and Marwitz, 1980; Hobbs,
1975b; Marwitz and Stewart, 1981). Since cold-cloud

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5"K

FIG. 2, Radar PPI patterns for each of the seven precipitation
echo types. Contours are 10 dB(Z) intervals beginning with 10 dB(Z).
Range ring is 30 km in diameter, (a) Orographic echo, (b) area-wide
echo, (c) convective train echo, (d) C2 echo, (e) Cl echo, (f) time
series of PPI showing west-to-east movement of an embedded band,
(g) time series of PPI showing west to east movement of a major
band,

seeding is an attempt to introduce ice crystals into a
cloud and convert liquid water to ice crystals, we believe
that a simultaneous measure of these two variables is
necessary to develop a quantitative measure of seed-

FIG. 3. Mean lapse rates of equivalent potential temperature for the precipitation echo types.

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302.9
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302,6 -eemax(oK)
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