TY - Generic T1 - The Documentation of Extreme Events: Two Case Studies in Utah, Water Year 2005 T2 - 73rd Annual Western Snow Conference Y1 - 2005 A1 - Bardsley, T. A1 - Julander, R. KW - NRCS, SNOTEL, extreme precipitation, Santa Clara River, flooding AB - The Natural Resources Conservation Service (NRCS), formerly the Soil Conservation Service, has monitored mountain snowpack and precipitation in the Western United States since 1934. The automation of measurement sites began in the late 1970s and now over 700 SNOw TELemetry (SNOTEL) sites are installed, most reporting hourly. The established length of record and hourly records now make it possible to evaluate and document extreme hydrometeorlogical events. Two recent events in Utah brought attention to the current lack of protocol for documenting extreme events. During October 20 - 22, 2004 the twenty four hour precipitation intensities for six Utah sites exceeded the National Weather Service estimated 100-year average return interval, and eleven of seventy seven Utah sites with 15 years or longer record, measured the maximum twenty four hour precipitation intensity of record. A second event Jan 8th to 12th hit SW Utah with high intensity rains and snow leading to the flooding of the Santa Clara River and the destruction of over twenty homes. JF - 73rd Annual Western Snow Conference T3 - Proceedings of the 73rd Annual Western Snow Conference PB - Western Snow Conference CY - Great Falls, MT UR - sites/westernsnowconference.org/PDFs/2005Bardsley.pdf ER - TY - Generic T1 - Investigations toward understanding the spatial representativeness of SNOTEL measurements of snow water equivalence T2 - 70th Annual Western Snow Conference Y1 - 2002 A1 - Bardsley, T. A1 - McConnell, J. KW - SWE, Topography, Snow distribution, Temperature profile AB -

The spatial distribution of snow water equivalence (SWE) is important for accurately predicting water availability, particularly in semi-arid, high elevation regions typical of the Western United States where as much as 75 of stream flow originates as snowmelt. The Natural Resource Conservation Service (NRCS), formerly the Soil Conservation Service, provides much of the data currently available for operational snow hydrology in the Western United States through its Snow Telemetry (SNOTEL) and snow course network. While this network provides a valuable index to seasonal runoff, little is known about how well these stations represent the local snow distribution. This is of utmost importance as snow hydrologists look for data sources for ground truth of remote sensing applications and move towards physically based snowmelt models. Intensive field campaigns in the Colorado Rockies and the Sierra Nevada have been conducted to address these issues on the scales of 30m x 30m and 1km2. Both grid sizes are commonly used in Digital Elevation Models (DEM) and satellite remote sensing.Our results indicate that the measured SNOTEL sites tend to over represent SWE in their local areas.

JF - 70th Annual Western Snow Conference T3 - Proceedings of the 70th Annual Western Snow Conference PB - Western Snow Conference CY - Granby, Colorado UR - sites/westernsnowconference.org/PDFs/2002Bardsley.pdf ER -