|
<br />26
<br />
<br />were generally more interested in the effeot of seeding rate, or 101 tial
<br />
<br />conoentration of ice nuclei, on modeled precipitation.
<br />
<br />Similar results were achieved in both models. It was conoluded
<br />
<br />_....~-'......-.-_...,~---.~-_..._--~ --~.,,,-,,",-",....". , ,,,. ~""","""r__""""""
<br />
<br />that the impact of ioe nucleation~~e. amount and location of
<br />
<br />....
<br />
<br />precipitation at the surface and precipitation efficienoy, strongly
<br />.,'."."-,,. ", '-' - ..... ,-,.. . "-:","-",_,":',.,,.,~.- .,',c...,...._._'..'"_."'_,_._ .~".,..:..".i..;.d-.'-....' --.,.....__..,...
<br />
<br />LO__""'"''''''-~''~:'''''='=':''''"'''''''''--"'~<''=-'''''''-:,V-''-''''' ..
<br />
<br />depend on the location of ice initiation and tile initi.el. oo,noentrati(>,n
<br />
<br />~,........~,~,...,_.......".~.>~""'.._"___,:_.-"...."'"'J":~".,,'_,,."___<~'__.:_'~_ ' ",-
<br />
<br />of ioe embryos.
<br />
<br />"......'".,'~.-_.""""'."..,.,~,.."._---..._',... ,--"":.",,,.,."
<br />
<br />2.4 Use of A2I-NaI in Weather Modi~ication Prc1ects
<br />
<br />A comprehensive explaination of the conoepts and methods of weather
<br />
<br />modification for preoipitation enhancement can be tound in Dennis
<br />
<br />(l'SO). Basioall7, when clouds are seeded with ioe nuclei, increased
<br />
<br />oonversion of water vapor or liquid water to ice is sought. Weather
<br />
<br />modification projects, for the most part, used 2AgI'NaI aerosol
<br />
<br />particles until approximatel7 1970. At that time AgI-HH4I-acetone
<br />solutions became more widely used in an effort to optimize the
<br />etfectivity/oost ratio of AgI in weather modification and to improve the
<br />likelihood ot oloud response at warmer temperatures (W. G. Finnegan,
<br />
<br />personal oClllDlun1cation). Only one major weather modification project..
<br />
<br />the Israeli program.,. ~92P~J,ll\l"to use 2AgI"..NaI seeding material from
<br />" '.-': '..... .. .--, - '...-' ','- ':-.c',:" "0-'_ i'_:'''~h:..:",..'", .. ..:..
<br />
<br />acetone combustion generators CA. Oagin, personal oommunication).
<br />
<br />Aerosols of 2AgI'NaI partioles have been used for both orographio
<br />and conveotive oloud seeding in countries worldwide (Dennis, 1980). The
<br />
<br />most notable of these programs are the Climax experiments and the
<br />
<br />Israeli program. Climax was a wintertime, orographio snowfall
<br />
<br />enhanoement projeot conducted in the Colorado Rocky Hountainsfrom 1960
<br />
<br />to 1'70. The Israeli program, still in progress, is a convective
<br />
<br />rainfall enhancement project which began in 1961. Seeding in both
<br />
<br />I
<br />I
<br />I
<br />I
<br />I
<br />I
<br />I
<br />I
<br />I
<br />I
<br />I
<br />I
<br />I
<br />I
<br />I
<br />I
<br />I
<br />I
<br />I
<br />
|