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Pyramid Lake Pilot Project The Desert Research Institute (DR!) ran the Pyramid Lake Pilot Project as a part of Project Skywater from 1972 to 1975. 13/ It was concluded in the DRI report that "The measurement of precTj)'itation in the form of snow by means of typical recording gages is inaccurate * * *" It was also concluded that even if precipitation could be measured with sufficient accuracy at a number of gage sites in mountainous terrain, serious problems are involved in deriving an estimate of the total volume of precipitation over a !Jiven area for a given period. The method of interpolating between observations is the simplest procedure but is not reliable in mountainous terrain. Therefore, DRI tested an X-band radar on ~quaw Peak, California, for estimating areal precipitation. The radar was remote controlled and operated at about 2700 meters (8900 feet) elevation. Although conclusive evidence was not developed during the program, case studies did show that the radar data indicate similar levels of precipitation as reported from ground measurements, and there appears to be potential for further development. ,- High Plains Cooperative Program Technology development has continued in Project Skywater through work on the High Plains Cooperative Program (HIPLEX), a research program with field sites in Montana, Kansas, and Texas. The program incor- porates a full range of instrumentation for measuring precipitation from a dense network of "fence post" gages to satellite. In order to compensate for the sparsity of rain gages, remotely sensed measu rements are bei ng made for the HI PLEX IVlil E~S City, Montana site. In making a gage to radar intercomparison, the ideal situation is to compare the data from the most representative sector observed by the radar with the gage data, taking into consideration the horizontal movement of precipitation particles and time correc- tions to account for the time interval oetween radar detection and gage detecti on. A compari son' between data collected l)y the Skywater 5-cm raoar dnd 18 precipitation gages at Miles City iMicated that under some storm conditions radar can provide estimates of precipita- tion. 14/ However, with small echoes, over a large area with short lifetimes and with intentional modification of the nOl"mal drop-size distribuClor, the difficulty of using radar increases for detecting small changes. 'U Another remo~e measuring device is the SMS/GOES satellite which is capable of mbnitoring clouds and ClOUd systems and is now being tested for making remute rainfall measurements. 15/ The most promising technique is the Scofield-Oliver method which momtors the decrease 6