WMOD00315 ‎(2)‎

• Title: Colorado River Augmentation Demonstration Program - Technical Report January 1983 - March 1985
• Date: 4/1/1986
• Weather Modification - Doc Type: Report

7-2090 (4-81)
Bureau ot Reclamation

TECHNICAL REPORT STANDARD TITLE PAGE

I. REPORT NO. II. GOVERNMENT ACClSSION NO. 3. RECIPIENT'S CATALOG NO.
4. TITLE AND SUBTITLE 5. REPORT DATE
Colorado River Augmentation Demonstration April 1986
Program: Technical Report 6. PERFORMING ORGANIZATION CODE
January 1983 - March 1985 D-1230
7. A UTHOR(S) 8. PERFORMING ORGANIZATION
Arlin B. Super, Edmond W. Holroyd, III, Bruce A. REPORT NO.
Boe, and Jack T. McPartland
9. PERFORMING ORGANIZATION NAME AND ADDRESS 10. WORK UNIT NO.
Bureau of Reclamation
Montrose Skywater Office II. CONTRACT OR GRANT NO.
2075 East Main
Montrose, CO 81401 13. TYPE OF REPORT AND PERIOD
. COVERED
12. SPONSORING AGENCY NAME AND ADDRESS
Bureau of Reclamation
Division of Atmospheric Resources and Research
Engineering and Research Center
P.O. Box 25007 14. SPONSORING AGENCY CODE
Denver, CO 80225 DIBR
15. SUPPLEMENTARY NOTES
Microfiche, and/or hard copy available at E & R Center, Denver, Colorado.
Editor:RDM
16. ABSTRACT
Wintertime field investigations of clouds and precipitation were conducted from January 1983 through March
1985 over the Grand Mesa of western Colorado. Resulting analyses are discussed including spatial and
temporal distributions of SLW (supercooled liquid water), precipitation characteristics, airborne and ground-
based ice particle observations, and the meteorological conditions associated with these cloud and precipitation
phenomena.
It was observed that SLW frequently occurred over the Mesa. The large number of hours with limited amounts
contributed to a significant SLW flux. The SLW often formed over the windward slopes, persisted over the
top, and rapidly evaporated to the lee of the barrier. Nature was inefficient in converting the SLW into
precipitation in many cases.
The Mesa created distortions in the free air flow. The wind in the lowest 500 m was slowed down over the
windward slope and, for southwesterly or northwesterly directions, was turned approximately perpendicular
to the barrier axis. The wind then accelerated over the lee slopes.
A number of instrumentation intercomparisons are described. Systems include microwave radiometers, icing
detectors, precipitation gauges, and radars used for cloud top observations.
17. KEY WORDS AND DOCUMENT ANALYSIS
a. DESCRIPTORS-- weather modification/cloud seeding/cloud physics/orographic precipitation/water
resources management/induced precipitation/precipitation (atmospheric) / precipitation gauges/meteorology /
weather/wind
b. IDENTlF/ERS-- Grand Mesa, Colorado/Colorado River Basin/Colorado River Augmentation Dem-
onstration Program/Rocky Mountains/Colorado
c. COSATI Field/Group 04A COWRR: 0401 SRIM:
18. DISTRIBUTION STATEMENT 19. SECURITY CLASS ~t. NO. OF PA GES
Available from the Notional Technical Information Service, Operations (THIS REPORT) 42
UNCLASSIFIED
Division, 5285 Port Royal Road, Springfield, Virginia 22/6/. 20. SECURITY CLASS 22. PRICE
(Microfiche and/or hard copy available from NTIS) (THIS PAGEl
UNCLASSIFIED

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