Due to increasing demands on water supplies and the negative effDue to increasing demands on water supplies and the negative effects of climate ects of climate

variability and change, south east Queensland frequently suffersvariability and change, south east Queensland frequently suffers severe water severe water

shortages. Based on recent scientific advances in cloud seeding shortages. Based on recent scientific advances in cloud seeding techniques, a techniques, a

research project was commissioned by the Queensland Government research project was commissioned by the Queensland Government in 2007. The in 2007. The

aim of the project is to investigate the potential for cloud seeaim of the project is to investigate the potential for cloud seeding technologies in the ding technologies in the

Somerset and Wivenhoe catchments of south east Queensland as parSomerset and Wivenhoe catchments of south east Queensland as part of the solution t of the solution

to the regions water shortages.to the regions water shortages.

The ongoing project has involved over 40 dedicated personnel, reThe ongoing project has involved over 40 dedicated personnel, research aircraft and search aircraft and

the Bureau of Meteorologythe Bureau of Meteorology’’s advanced weather radar facilities located at Redbank s advanced weather radar facilities located at Redbank

Plains and Mt Plains and Mt StapyltonStapylton. During the first season, which took place from December . During the first season, which took place from December

2007 to March 2008, randomised seeding experiments were carried 2007 to March 2008, randomised seeding experiments were carried out to quantify the out to quantify the

effect of hygroscopic seeding using pyrotechnic flares which releffect of hygroscopic seeding using pyrotechnic flares which release small particles of ease small particles of

potassium chloride at the base of convective clouds (potassium chloride at the base of convective clouds (BruintjesBruintjes, 1999)., 1999).

Research into the Research into the climatologicalclimatological characteristics of precipitation in the target area characteristics of precipitation in the target area

including the frequency of cumulus clouds suitable for seeding hincluding the frequency of cumulus clouds suitable for seeding has also been as also been

undertaken. The CP2 undertaken. The CP2 polarimetricpolarimetric radar at Redbank Plains and the local Bureau of radar at Redbank Plains and the local Bureau of

Meteorology radar network are used to evaluate the effects of seMeteorology radar network are used to evaluate the effects of seeding on precipitation eding on precipitation

flux, duration and storm dynamics including secondary cell initiflux, duration and storm dynamics including secondary cell initiation. Radar estimates ation. Radar estimates

of precipitation are calibrated using a groundof precipitation are calibrated using a ground--based video based video disdrometerdisdrometer. Cloud . Cloud

microphysical data was collected by the research aircraft which microphysical data was collected by the research aircraft which was equipped with was equipped with

over 20 microphysical recording instruments.over 20 microphysical recording instruments.

The program has been highly successful in providing cloud statisThe program has been highly successful in providing cloud statistical data for the tical data for the

target area in addition to evaluating aircraft based hygroscopictarget area in addition to evaluating aircraft based hygroscopic seeding activities. Subseeding activities. Sub--

tropical maritime warm shallow convective clouds rather than thetropical maritime warm shallow convective clouds rather than the more potentially more potentially

suitable deep convective cloud systems were a feature of the firsuitable deep convective cloud systems were a feature of the first seasons weather. st seasons weather.

Although positive trends in terms of increased cell duration areAlthough positive trends in terms of increased cell duration are apparent in the data, apparent in the data,

the number of randomised cases (27) is not sufficient to draw stthe number of randomised cases (27) is not sufficient to draw statistically significant atistically significant

conclusions regarding the efficacy of hygroscopic seeding of theconclusions regarding the efficacy of hygroscopic seeding of these clouds. This se clouds. This

important scientific research program has continued into the 200important scientific research program has continued into the 20088--2009 season. 2009 season.

Based on results to date there is strong incentive for further rBased on results to date there is strong incentive for further research into the esearch into the

hygroscopic seeding of deep convective clouds throughout south ehygroscopic seeding of deep convective clouds throughout south east Queensland ast Queensland

and its potential for inland catchments.and its potential for inland catchments.

BruintjesBruintjes, R. 1999 A review of cloud seeding experiments to enhance preci, R. 1999 A review of cloud seeding experiments to enhance precipitation and pitation and

some new prospects. Bull. Am. Met. Soc. 80(5) 805some new prospects. Bull. Am. Met. Soc. 80(5) 805--820.820.

TessendorfTessendorf, S.A., and co, S.A., and co--authors, 2008: Preliminary observations of cloud and authors, 2008: Preliminary observations of cloud and

precipitation characteristics in the Brisbane, Australia region.precipitation characteristics in the Brisbane, Australia region. International Conf. on International Conf. on

Clouds and Precipitation, International Commission on Clouds andClouds and Precipitation, International Commission on Clouds and Precipitation, Precipitation,

Cancun, MexicoCancun, Mexico

Queensland Cloud Seeding Research Program

QCSRP

Ian Craig and Roger StoneAustralian Centre for Sustainable Catchments (ACSC)

University of Southern Queensland, Australia

Project overview

Contact Details: craigi@usq.edu.au@usq.edu.auACSC Website: www.usq.edu.au/acsc

Figure 1: Figure 1: SAWS/WITSSAWS/WITS AerocommanderAerocommander 690A research aircraft (upper left), DMT CAPS probe (upper righ690A research aircraft (upper left), DMT CAPS probe (upper right), t),

BOM/NCAR CP2 dual wavelength BOM/NCAR CP2 dual wavelength polarimetricpolarimetric radar (centre left), vertical section image through a hail storradar (centre left), vertical section image through a hail storm (centre m (centre right), hygroscopic flare in operation below a convective cloud right), hygroscopic flare in operation below a convective cloud (lower left), WMI/MIPD Cheyenne II randomised (lower left), WMI/MIPD Cheyenne II randomised

seeding aircraft (lower right), seeding aircraft (lower right),

Craig I1, Stone R 1, Bruintjes R2, Tessendorf S2, Axisa D2, Dixon M2, Pocernich M2, Brandes E2,

Ikeda K2, Wilson J2, Roberts R2, Breed D2, Ziady L2, Peter J3, Manton M3, Seims S3, May P4

Keenan T4, Glasson K4, Gunn B4, Collis S4, Abbs D5 Piketh S6, Orsmond R6, McGarry H6,

Edwards S6, Burger R6, Kruger H6, Wiggins G6, Hingst J6, Broccardo S6, Nierop N6, Waal K6,

Kroese N6, Nchpa X6, Brailall S6, Walton N6, Brady P7, Choma G7, Smith D7, O’Donnell N7,

Carr J7, O’Doherty N7 McRae D8 Fitzmaurice L8

1 University of Southern Queensland (USQ); 2 US National Centre for Atmospheric Research (NCAR)

3 Monash University, Melbourne (Monash) 4 Australian Bureau of Meteorology (BoM)

5 Commonwealth Scientific and Industrial Research Organisation (CSIRO)

6 Witwatersrand University / South African Weather Service (WITS/SAWS)

7 Weather Modification Inc / MIPD (WMI / MIPD)

8 Queensland Climate Change Centre of Excellence/Environmental Protection Agency (QCCCE/EPA)

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