TY - Generic T1 - Understanding Trends in Snow Accumulation, Water Availability, and Climate Changes Using Snow Telemetry and Streamflow Observations in the Missouri River Headwaters T2 - 81st Annual Western Snow Conference Y1 - 2013 A1 - Matthews, Tom KW - climate KW - Missouri KW - SNOTEL KW - snow hydrology KW - temporal trends AB -

The Missouri River headwaters are located in the mountains of southwestern Montana, and serve as a water source for 10 states and approximately 10 million people. A key component of the annual water budget in this headwater region is from snowfall, accounting for around 70% of the total annual flow. The Western U.S. is comprised of semi-arid to arid regions that exhibit a high degree of inter-annual to multi-decadal variability. Changing trends in water availability due to climate change and yearly variations must be understood and quantified for proper allocation and forecasting of water resources. Here we use snow, temperature and precipitation records from the Natural Resource Conservation Service (NRCS) and streamflow records from the U.S. Geological Survey (USGS) in a coupled analysis designed to assess recent changes in these temperature sensitive high alpine headwaters over the last 40 years of record. Snow water equivalence, snow depth, temperature and streamflow are key metrics that are indicative of changes in these headwater regions and are useful in determining the amount, timing and duration of hydrologically important snow-driven events. These data are being examined to determine what role inter annual and decadal drivers such as the El Niño Southern Oscillation (ENSO), the Pacific North American Pattern (PNA), and the Pacific Decadal Oscillation (PDO) play in controlling the amount and timing of water availability in this catchment. Metadata from the weather stations used in this study are being analyzed to determine how changes to the station, such as vegetation growth or equipment updates, could help explain any trends or relationships seen in the data beyond the natural climate variations.

JF - 81st Annual Western Snow Conference T3 - Proceedings of the Western Snow Conference CY - Jackson Hole, Wyoming UR - sites/westernsnowconference.org/PDFs/2013Matthews.pdf ER -