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<br />positions of inlcrest an.: the liAS seeding location, the <br />TAR instrum...'Tlted weather station, the four target <br />gauges GSC. GTR. GSO and GDN listed in order of <br />inc~asing downwind distance, and the GNO <br /> <br />crosswind control gauge. Figure 2 shows the <br />instrumented TAR station instruments atop a <br />platform at about 25 11 ahove ground level. <br /> <br /> <br />FIgure 2.1 he TAR InSlrumcnt...-d target faelhul'S In early wmler 101lkmg toward lhe we't.soulh....C'oI. The po....er gcrn:n.llJr and <br />salellile dIsh for Imemel connection arc on {he far righl. The inslrumcnllllion plulfllrm wu immedialcly .....C"t of the hcated trailer <br />....hich housed eompulCf'S, clectronics and other equipment. <br /> <br />l'limnry measuren~nts for statistical e\'aluation <br />wcre from high resolution precipitation gauges <br />protected from the wind in small natural clearings in <br />evergreen forest. They were equipped with Aller- <br />type wind shields to fur1her n..-duce .....ind-caused <br />undercatch, a serious problem for snowfall <br />observations. Gauge time resolution was about I <br />minute and data logger times were quite stable, <br />frequently checked agninst a standnrd time signal. <br />Each of the highly sensitive load cell gauges was <br />carefully calibratcd and the individual coefficients <br />were used in mat gaugc's data logger program .....hich <br />COl1ve:-nl-d the weight oflhe antifre:-eze and melted <br />sno..... wat!.'r solution into recorded I minute averages. <br />1ne gauges proved to ~ ,'cry reliable, ~ult1l1g in no <br />missing Jatn for any e.'lpcrimcntal period. figure 3 <br />show the control gauge with data from the data <br />logger being do.....nloaded into a Palm rilot de:\'ice a~ <br />was done during approximall"ly wcckly SC'T'\'ice visits. <br />1nl."!lC data "'ere transmitted 10 projl."Ct scie:ntists via <br />the Inlem~t. Running means offiw "'ere lined 10 all <br />I minutl." glluge samples. eelllered on the middll." <br /> <br />minute. before making calculations ofSWE <br />accumulations on"r time. Examination of res lilting <br />smooth time hi~tory plots suggested that gauge <br />resolution was bclwa'l\ 0.002 and 0.1)()3 inch SWE, <br /> <br />Thrl"C propan~ dispensers .....ere: used at the liAS <br />SC'l-ding site. located aboUlIOO feet apar1 on an axis <br />across the prevailing southwest wind to reduce <br />aggregation losses of the high initial concentralions <br />of seeded ice crystals. Two noules were used with <br />each disp.=nSl."f at the ends of a 10 foot horizontal <br />tube, again to reduce aggregation. All dispenser <br />valve controllers, propane no.....mcters and <br />lemperalure sensors ncar ~ach propane noale .....ere <br />hard-wired into a dala logger at the central dispenser. <br />Figure 4 sho.....s the central propane dispenser and <br />instrutllC'nloo lOwer at liAS with the view toward the:- <br />south-southeast. The propane conlrolkr and data <br />logger were in the box atlhe base of the tower, A <br />propane dispenser is a relalively simple and <br />inexpensive device, consisting of a prupane supply. <br />readily available from commercial sources, an <br /> <br />4 <br />