WMOD00454

• Title: Preliminary Analysis of the Hypotheses Used in the Utah Operational Weather Modification Program - Final Report
• Date: 11/1/1983
• Weather Modification - Doc Type: Report

18

Utah and the information network used during the field program. Table V

lists the instrumentation used, the suppliers, and operators.

This preliminary study utilizes data collected by the CIC Cheyenne II

cloud physics aircraft, the Ku-band radar, rawinsondes, the ground-based

""

supercooled water detector, and the precipitation gage network. The operation

of the supercooled water detector, precipitation gages, and the rawinsonde

facility are described in other documentsl,2. Because of the importance

of the Ku-band radar and CIC aircraft to this analysis, a complete description

of these instruments is given in Appendixes Band C. Because the primary

goal of the first year analysis is to describe the spatial and temporal

variation of supercooled cloud water, a detailed comparison of the instruments

measuring this parameter, the Johnson Williams (JW) liquid water content

meter and Forward Scattering Spectrometer Probe (FSSP), is presented.

D. A Comparison of the Cheyenne II Aircraft Liquid Water Measurements
with the JW and FSSP Probes

Analysis of Cheyenne II aircraft data during the first year at CSU

;:

concentrated on addressing the problem of determining the distribution

of supercooled liquid water during two research flights. Three devices

were available to measure liquid water contents on the Cheyenne II, a

CSIRO (King) Probe hot wire device, a Johnson-Williams (JW) hot wire

device, and a forward scattering spectrometer probe (FSSP). The CSIRO

device was experimental and produced little useful quantitative data.

Data from this probe are not included in this report. The JW and FSSP

operated reliably throughout the program.

1
Henderson, T.H., (1982): The detection of supercooled liquid water. Final
Report tothe State of Utah, Division of Water Resources. Atmospherics, Inc.,
Fresno, CA (available from UDWR).

2Swart, R.N. and D.A. Griffith, 1983: Utah/NOAA "piggy-back" research study
on the Utah operational cloud seeding project. Operations Report JLEM-83-l,
NAWC, Salt Lake City, UT (available from UDWR).

~