TY - Generic T1 - Improving Streamflow Forecasts in the NOAA National Water Model Using Observational Constraints on Snowpack Albedo and Snow-Covered Area from STC-MODSCAG (Extended Abstract) T2 - 88th Annual Western Snow Conference Y1 - 2021 A1 - Thomas L. Enzminger A1 - Aubrey L. Dugger A1 - Karl Rittger A1 - Edward H. Bair A1 - James L. McCreight A1 - Mark S. Raleigh A1 - Mary J. Brodzik KW - MODSCAG KW - National Water Model KW - snow-covered area KW - snowpack albedo KW - streamflow AB -

The NOAA National Water Model (NWM) is a physically-based modeling system which simulates major hydrologic processes across the conterminous United States (US). Difficulties in accurately simulating snowpack states hinder the NWM’s ability to provide high-quality streamflow forecasts, particularly in snow-dominated western US mountains. Errors in snowpack simulations propagate into streamflow time series as errors in both magnitude and timing of peak streamflow in snow-dominated basins.


We imposed observation-based constraints on simulated fractional snow-covered area (fSCA) and snowpack albedo in the NWM using remotely sensed data and investigated the impacts on simulated snow states and streamflow over the Upper Colorado River Basin. We identified a set of parameters that influence the relationship between snow depth and fSCA (the snow depletion curve) and seasonal snowpack evolution. For each parameter, we derived spatially-distributed values using 15 years of data from STC-MODSCAG (Spatially and Temporally Complete MODIS Snow-Covered Area and Grain Size), which provides daily estimates of fSCA, snowpack albedo, and other variables at ~500 m spatial resolution. When implemented into the NWM’s snow model, the derived values tended to shift simulated streamflow peaks lower and earlier, often improving agreement with observed streamflow. Results from these experiments will help to improve streamflow forecasting for water management and inform NWM data assimilation strategies with model parameter uncertainties.

JF - 88th Annual Western Snow Conference CY - Bozeman, MT UR - /files/PDFs/2021Enzminger.pdf ER - TY - Generic T1 - Impact of Future Climate On Water Availability of Snowmelt-Dominated Watersheds of the Upper Rio Grande Basin T2 - 82nd Annual Western Snow Conference Y1 - 2014 A1 - Emile Elias A1 - Albert Rango A1 - Caiti Steele A1 - John F. Mejia KW - climate change KW - Rio Grande Basin KW - snowmelt runoff model KW - water resources AB -

Climate change is predicted to further limit the water availability of much of the arid southwestern U.S. In this study, the Snowmelt Runoff Model is used to evaluate the impacts of increased temperature and altered precipitation of a changed climate on snow covered area, streamflow timing and seasonal and total volume in the Upper Rio Grande. Simulations investigate a fairly hot and dry future condition at the end of the 21st century using a regionally recommended general circulation model downscaled to existing climate stations. Twenty-four subbasins of the Upper Rio Grande containing appreciable snowmelt and a long-term gauging station are simulated. Total basin snow covered area decreased by 55%due to future temperatures. SRM simulation shows that total annual 2099 volume for all basins was between 13% and 33% lower than 1999 total annual volume. Among the 24 basins there is considerable range in decrease in snow covered area (6-87%), total volume reduction (4-34%) and runoff timing shift (0-60 days early) indicating that climate change impacts are best evaluated at the subbasin scale in mountainous regions. Daily hydrographs for the snowmelt basins show higher streamflow in March and April, but less from mid-May until the end of the water year. SRM simulation provides a rapid and effective evaluation of the most resilient basins under a changed climate for planning and management purposes.

JF - 82nd Annual Western Snow Conference T3 - Proceedings of the Western Snow Conference CY - Durango, Colorado UR - sites/westernsnowconference.org/PDFs/2014Elias.pdf ER - TY - Generic T1 - Relational databases as a tool to manage environmental data at the research plot scale T2 - 70th Annual Western Snow Conference Y1 - 2002 A1 - Erickson, T. A1 - Donahue, D. KW - Relational database, Environmental data, Mammoth Mountain, Meteorological data AB - Relational databases management systems (RDBMS) can be used as highly effective storage systemsenvironmental data. RDBMS are most suited to storing large volumes of repetitive data. RDBMS offer significantadvantages over data storage methods (such as ASCII text files or spreadsheet programs) by offering flexibility in the types of information stored, speed of retrieval, and the ability to share data with other computer programs. Information contained in RDBMS can be accessed through desktop programs or may be distributed over the Internet. However, RDBMS may not be appropriate for all types of collected data, especially when the format ofthe data changes frequently. Snow hydrology data can be efficiently stored in a RDBMS, particularly if many repetitive measurements aremade in time or in space, such as automated meteorological measurements obtained from data loggers. Intelligently designed RDBMS link metadata to the collected data and allow scientists to analyze and store comments on the quality of the data. Design issues encountered during the processes of data modeling, database design, and data distribution are described. Examples are taken from the currently operational Mammoth Mountain Energy Balance Monitoring Site database and a sample data model created to store information on Western Snow Conference(WSC) members and papers. 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/2002Erickson.pdf ER - TY - Generic T1 - Comparison of spatial interpolation methods for estimating snow distribution in the Colorado Rocky Mountains T2 - 70th Annual Western Snow Conference Y1 - 2002 A1 - Erxleben, J. A1 - Elder, K. A1 - Davis, R.E. KW - SWE, Spatial interpolation, Colorado, Kriging, Binary regression tree AB - In this study, the relative performances of four spatial interpolation methods were evaluated to estimate snow water equivalent (SWE) for three 1 km2 study sites in the Colorado Rocky Mountains. Each study site is representative of different topographic and vegetative characteristics. From 1-11 April 2001, 550 snow depth measurements and approximately 16 snow density profiles were obtained within each study site. The analytical methods used to estimate snow depth over the 1 km2 areas were 1) inverse distance weighting, 2) ordinary kriging,3) modified residual kriging and co-kriging, and 4) a combined method using binary regression trees and geostatistical methods. The independent variables used were elevation, slope, aspect, net solar radiation, and vegetation. Using cross-validation procedures, each method was assessed for accuracy. The tree-based models provided the most accurate estimates for all study sites, explaining 18-30 of the observed variability in snowdepth. Binary regression trees may have generated the most accurate estimates out of all methods evaluated, however, substantial portions of the variability in observed snow depth were left unexplained by the models. While the data may have simply lacked spatial structure, it is recommended that the characteristics of the study sites, sampling strategy, and independent variables be explored further to evaluate the causes for the relatively poor model results. 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/2002Erxleben.pdf ER - TY - Generic T1 - LANDSCAPE CONTROLS ON SNOW ACCUMULATION IN AN ALPINE CATCHMENT T2 - 69th Annual Western Snow Conference Y1 - 2001 A1 - Erickson, T. A1 - Williams, M.W. A1 - Tomaszewski, M. KW - Roughness, Snow distribution, Topographic control AB - The central question addressed by this poster is relationship between landscape types and snow accumulation. Of particular interest is the relative amount of snow accumulation in talus areas. Talus areas play an important role in alpine hydrology because these areas have been shown to provide water late into the summer growing season. One reason that talus areas may provide important sources of water late into the growing season is because they accumulate more snow than other landscape types in alpine basins. The roughness of talus areas reduces the redistribution of snow by wind, which may cause an increase in accumulation. Furthermore, talus areas are often located beneath steep rock faces, and these areas may accumulate relatively high amounts of snow due to sluffs and avalanches.Snow surveys were conducted at maximum accumulation in the Green Lakes Basin in the Colorado Front Range during the years 1997 through 2000. This basin has been extensively studied in the past, and the major landscape types have been mapped and digitized onto a GIS. Using a combination of field measurements and geostatistical techniques we have estimated the distribution of snow water equivalent throughout the basin and compared it to the mapped landscape types. JF - 69th Annual Western Snow Conference T3 - Proceedings of the 69th Annual Western Snow Conference PB - Western Snow Conference CY - Sun Valley, Idaho UR - sites/westernsnowconference.org/PDFs/2001Erickson.pdf ER - TY - Generic T1 - Measuring and monitoring snow depth using the global positioning system T2 - 67th Annual Western Snow Conference Y1 - 1999 A1 - Elder, K. A1 - Gray, M. A1 - Major, P. A1 - Nyberg, C. KW - GPS, Snow depths AB - Ski resorts need to monitor snow depth over their slopes from the start of the accumulation or snowmaking season until spring closure. There is currently no system available that provides real-time, high-resolution, high-frequency data for mapping snow over space on an operational basis. Air- and space-borne sensors either lack the spatial resolution or temporal frequency necessary for daily ski resort operations. In addition, inclement weather reduces the capabilities of sensors in the visible portion of the spectrum. We evaluated the potential of the Global Positioning System (GPS) to meet the operational needs. We used post processed kinematic GPS equipment for a static survey over a fixed transect to find the capabilities of the system to detect changes in the elevation of the snow surface through time and over space. The GPS equipment was also mounted on over-snow vehicles to determine the effect of vehicle movement on GPS accuracy. Our results suggest that GPS equipment should allow ski resorts to measure snow depth well within the study design constraints of 0.15 m. JF - 67th Annual Western Snow Conference T3 - Proceedings of the 67th Annual Western Snow Conference PB - Western Snow Conference CY - South Lake Tahoe, California UR - sites/westernsnowconference.org/PDFs/1999Elder.pdf ER - TY - Generic T1 - Estimating spatial distribution of snow water equivalence in a montane watershed T2 - 65th Annual Western Snow Conference Y1 - 1997 A1 - Elder, K. A1 - Rosenthal, W. A1 - Davis, R.E. KW - Kings River, LandSat, Modeling AB - We describe an approach to model distributed snow water equivalence (SWE) that merges field measurements of depth and density with remotely sensed snow-covered area (SCA). In 1993 two teams conducted an intensive snow survey in the 92.8 km2 Blackcap Basin of the Kings River. We measured snow depth at 709 points and density in five snow pits and along five transects using a Federal Sampler. Sample locations were chosen to be representative of the range of elevations, slopes and aspects of the basin. Regression tree models showed that net radiation, elevation, and slope angle account for 60- 70% of the variance in the depth measurements. Density was distributed over the basin on a 30 m grid with a multiple linear regression model that explained 70% of the observed variance as a function of the same three variables. The gridded depth estimates combined with modeled density produced spatially distributed estimates of SWE. An unsupervised spectral unmixing algorithm estimated snow cover fractions from Landsat-5 Thematic Mapper data acquired at the time of the snow survey. This method provides a snow cover fraction estimate for every pixel. We used this subpixel map as our best estimate for SCA and combining it with the SWE map allowed us to compute SWE volume. We compared the estimated volume using the subpixel SCA map with several SCA maps produced with simulations of binary SCA mapping techniques. Thresholds of 40%, 50% and 60% fractional cover were used to map binary cases of full snow cover or no snow cover. The difference in basin SWE volume was up to 13% depending on the threshold used to classify snow-covered versus snow-free areas. The percent differences in volumes roughly couesponded to the percent differences in SCA between the methods. JF - 65th Annual Western Snow Conference T3 - Proceedings of the 65th Annual Western Snow Conference PB - Western Snow Conference CY - Banff, Alberta UR - sites/westernsnowconference.org/PDFs/1997Elder.pdf ER - TY - Generic T1 - Windy gap project streamflow forecasting T2 - 53rd Annual Western Snow Conference Y1 - 1985 A1 - Eckhardt, J.R. A1 - Leaf, C.F. A1 - Baker, D. KW - Snowmelt runoff, Streamflow forecasting AB - The recently constructed Windy Gap Project is operated by the Municipal Subdistrict of the Northern Colorado Water Conservancy District. Key elements of the project include: (a) a diversion dam on the Colorado River, and (b) a pumping plant and pipeline which transports diverted water to the Colorado-Big Thompson System for subsequent storage and distribution to the Platte River Power Authority and the cities of Boulder, Estes Park, Greeley, Longmont, and Loveland. The basis for timely residual volume streamflow forecasts is a remote hydrologic data collection network which utilizes the GOES Satellite for data transmission to project headquarters in Loveland, Colorado. Snowpack, soil moisture, streamflow, precipitation, temperature, and wind data collected at 16 remote sites in the Fraser River Basin are used to update a computerized hydrologic simulation model. This process-oriented model, developed from Forest Service research and pilot-tested in NASA's Colorado ASVT on Satellite Snow Cover Observations, is being used for making forecasts of residual streamflow available to the Windy Gap Project. JF - 53rd Annual Western Snow Conference T3 - Proceedings of the 53rd Annual Western Snow Conference PB - Western Snow Conference CY - Boulder, Colorado UR - sites/westernsnowconference.org/PDFs/1985Eckhardt.pdf ER - TY - Generic T1 - Eastern snowpack conditions - characteristics and significance T2 - 50th Annual Western Snow Conference Y1 - 1982 A1 - Eschner, A.R. KW - Eastern U.S., Runoff, Snow accumulation, Snowpack AB - Eastern snowpack conditions are sharply different from those in the west; but not necessarily in the ways we might imagine. In New York, the seasonal snowfall approaches the average seasonal snowfall in many western areas, and is well correlated with melt season streamflow volumes. In spite of a substantial annual precipitation uniformly delivered over the year, the seasons when snow is present on the ground or in the process of melting provide the bulk of streamflow for many areas in the East. Although approximately as much precipitation falls in the growing season as the dormant season, its contribution to streamflow is small, and the snowpack is a significant parameter for predicting even total annual runoff. JF - 50th Annual Western Snow Conference T3 - Proceedings of the 50th Annual Western Snow Conference PB - Western Snow Conference CY - Reno, Nevada UR - sites/westernsnowconference.org/PDFs/1982Eschner.pdf ER - TY - Generic T1 - Microwave characteristics of snow T2 - 45th Annual Western Snow Conference Y1 - 1977 A1 - Ellerbruch, D.A. A1 - Little, W.E. A1 - Boyne, H.S. A1 - Bachman, D.D. KW - Microwave, Snow measurement AB - A program is underway at NBS to measure the microwave scattering characteristics of snow. Microwave signals nondestructively penetrate snow, but they are modified by the material properties of snow (density, free moisure content, resistance, temperature). There is a distinct possibility of developing miniaturized microwave instrumentation to remotely sense and measure those undisturbed snow properties as a function of time and depth. A portable FM-CW system was developed to measure electromagnetic profiles of snow packs down to ground level. This system was used to monitor changes in snow stratigraphy as a function of time of day. An Automated Network Analyzer system was used to measure the elecromagnetic scattering properties of snow at discrete frequencies over the range 250 MHz - 18 GHz. the snow was physically analyzed in terms of resistance, temperature, and density profiles, and by visual characterization. Some experiments included measurement of global radiation and liquid water at the snow surface. JF - 45th Annual Western Snow Conference T3 - Proceedings of the 45th Annual Western Snow Conference PB - Western Snow Conference CY - Albuquerque, New Mexico UR - sites/westernsnowconference.org/PDFs/1977Ellerbruch.pdf ER - TY - Generic T1 - Value of water supply forecasts to irrigated agriculture T2 - 45th Annual Western Snow Conference Y1 - 1977 A1 - Elliott, S.J. KW - Economics of water supply forecasting, Snow survey economic benefits, Water supply forecasting AB - A linear programming model is applied to three study areas of irrigated agriculture to produce matrices of revenues at various combinations of forecast and actual water supplies. Optimization techniques reveal value of forecast accuracy and the impact of error on revenues. Empirical data indicate value of agricultural production, number of irrigated acres served and vulnerability to water shortages for each forecast point. Comination of these data reveal potential loss of agricultural production due to forecast error and to lack of forecast. For various assumptions as to supplemental water supply the model shows net benefit to irrigators of water supply forecasts. JF - 45th Annual Western Snow Conference T3 - Proceedings of the 45th Annual Western Snow Conference PB - Western Snow Conference CY - Albuquerque, New Mexico UR - sites/westernsnowconference.org/PDFs/1977Elliott.pdf ER - TY - Generic T1 - Progrss in measuring snow cover from ERTS imagery T2 - 42nd Annual Western Snow Conference Y1 - 1974 A1 - Evans, W.E. KW - Snow cover photo analysis, Snow cover photo mapping, Snow line measurement, Snow measurement - aerial, Snow Measurement - photographic AB - A hybrid of digital and analog analysis techniques are being employed to determine the accuracy with which snow area and temporal change in snow area can be determined from ERTS satellite imagery. The principal analysis tool is an Electronic Satellite Image Analysis Console (ESIAC) which permits display of time-lapse sequences of color composite images on a color TV monitor. Binary snow maps are generated electronically, superimposed on the image display for any necessary human editing, them measured for area in a digital counter. Results are checked against high altitude aircraft photography.Bright snow is relatively easy to measure. Snow in shadow or illuminated at low incidence angles is harder to identify unambiguously. Several potential solutions for this problem and for the problem of snow-tree mixtures are being studied. A time-lapse movie showing a full year of ERTS imagery of a typical mountian snowfield will be shown. JF - 42nd Annual Western Snow Conference T3 - Proceedings of the 42nd Annual Western Snow Conference PB - Western Snow Conference CY - Anchorage, Alaska UR - sites/westernsnowconference.org/PDFs/1974Evans.pdf ER - TY - Generic T1 - Watershed hydrometeorological data required for weather modification T2 - 40th Annual Western Snow Conference Y1 - 1972 A1 - Elliott, R.D. A1 - Hannaford, J.F. KW - Cloud seeding, Water supply forecasting, Weather modification evaluation AB - The hydrometeorological data in five western mountain watersheds were reviewed and deficiencies in existing data required for planning of large scale research weather modification projects were noted. Ideally the additional data needed for each major watershed includes a base station for project control, several climate stations to record areal coverage of precipitation and standard meteorological parameters and one mountain observatory unit for the observation of special meteorological parameters and snow quality data. Studies of existing data reveals little or no tendency for snowpack to level off or to decrease at higher elevations. Estimates of ten percent increase in precipitation during the October through April seeding periods could increase the average annual runoff by 2.5 million acre feet within the five large watersheds and an additional 1 million acre feet around the periphery of these watersheds. Extending the seeding program into May and June could increase the runoff from the five study basins by 440,000 acre feet, but caution is needed in seeding during this period because of undesirable flood potentials. JF - 40th Annual Western Snow Conference T3 - Proceedings of the 40th Annual Western Snow Conference PB - Western Snow Conference CY - Phoenix, Arizona UR - sites/westernsnowconference.org/PDFs/1972Elliott.pdf ER - TY - Generic T1 - The optimum use of water for power calculated by Datatron electronic computer T2 - 26th Annual Western Snow Conference Y1 - 1958 A1 - Ellis, J.D. KW - Electronic computer, Hydro power, Water management AB - A description of the use of electronic computer for routing procedures of water supply of the Lewis River in southwest Washington for hydro-power development along a series of 7 plants, is presented. The computer complex is described and read-out sheets are shown to present the data available to the operator of reservoirs and to meet the power demands.In discussion Mr. David Rockwood describes electronic computer procedures carried on by the Corps of Army Engineers in the North Pacific Division Office at Portland, Oregon. He mentions the many advantages of Automatic Data Processing machines where large amounts of the data must be handled in a short time. JF - 26th Annual Western Snow Conference T3 - Proceedings of the 26th Annual Western Snow Conference PB - Western Snow Conference CY - Bozeman, Montana UR - sites/westernsnowconference.org/PDFs/1958Ellis.pdf ER - TY - Generic T1 - The Santa Barbara randomized cloud seeding program T2 - 25th Annual Western Snow Conference Y1 - 1957 A1 - Elliott, R.D. KW - Nucleation, Research program, Silver iodide, Weather modification AB - The seeding program began in January 1957 and is scheduled to continue for 3 years. The organization, history, operations thus far conducted, and the manner in which the seeding is carried out under the randomizing plan are discussed. No complete statistical analysis of results can be accomplished prior to completion of the project. However, thus far (January 10 - April 12, 1957), 4 storms have occurred yielding over an inch of precipitation in the mountains. Of these, two were seeded completely and one partially. The ground based silver iodide smoke generator layout and the recording rain gage network are shown on the location map. JF - 25th Annual Western Snow Conference T3 - Proceedings of the 25th Annual Western Snow Conference PB - Western Snow Conference CY - Santa Barbara, California UR - sites/westernsnowconference.org/PDFs/1957Elliott.pdf ER - TY - Generic T1 - Snow survey data in the Water Resources Review T2 - 21st Annual Western Snow Conference Y1 - 1953 A1 - Eisenlohr, W.S. KW - Data publication, Water supply forecasting AB - A plan is presented by the U.S. Geological Survey office at Washington D.C. to expand the distribution of the Water Supply Forecast volumes by publishing them in the April 1 issue of their nationally circulated WATER RESOURCES REVIEW. This publication and distribution would greatly enhance the reader volume of this information to a diversified number of readers. JF - 21st Annual Western Snow Conference T3 - Proceedings of the 21st Annual Western Snow Conference PB - Western Snow Conference CY - Boise, Idaho ER - TY - Generic T1 - Methods of evaluation of cloud seeding T2 - 20th Annual Western Snow Conference Y1 - 1952 A1 - Elliott, R.D. KW - Weather modification evaluation AB - Cloud-seeding experiments are hard to evaluate because of difficulty in segregating artificially created effects of seeding from natural processes. Control areas in the immediate vicinity which, from previously established records, are not liable to produce abnormal precipitation, should be chosen. It becomes increasingly difficult to find a control area which is not influenced by another cloud-seeding operation conducted nearby. JF - 20th Annual Western Snow Conference T3 - Proceedings of the 20th Annual Western Snow Conference PB - Western Snow Conference CY - Sacramento, California ER - TY - Generic T1 - Present trends in improving forecasting in the Humboldt Basin, Nevada T2 - 8th Annual Western Interstate Snow Survey Conference Y1 - 1940 A1 - Elges, C. KW - Water supply forecasting, Water supply forecasting AB - A hydrologic history of the Humboldt River in Central Nevada is presented. The geophysical features that cause so many discrepancies in the climatic changes and resulting difficulties in forecasting streamflow from the area are discussed. Mention is made of the 1910 flood and an attempt at analysing the causes from fragmentary hear-say data is given. Progress is reported in establishing climatological stations and some 31 show courses that will aid materially in the future to forecast the flow of the streams at the Paradise gaging station. Irrigation diversions are being measured. JF - 8th Annual Western Interstate Snow Survey Conference T3 - Proceedings of the 8th Annual Western Interstate Snow Survey Conference PB - American Geophysical Union, Transactions, Part III-B: CY - Seattle, Washington UR - sites/westernsnowconference.org/PDFs/1940aElges.pdf ER - TY - Generic T1 - Problems of using calcium chloride in precipitation gages T2 - 8th Annual Western Interstate Snow Survey Conference Y1 - 1940 A1 - Elges, C. KW - Calcium chloride, Storage precipitation gages AB - Cans of aqueous solution of Calcium Chloride of various concentrations were placed in a low temperature room at temperatures varying from -6 to -30 deg F. The results confirm data in the Chemical Engineers Handbook by John H. Perry (1934). An 8-in. gage charged to protect an expected 10 inches of precipitation to -20deg F will require an initial charge of 26.9 lb. commercial Calcium Chloride and 35.8 lb. water. The storage precipitation gage is not recommended if the gage must be unattended for month or more at below 0deg F temperatures. JF - 8th Annual Western Interstate Snow Survey Conference T3 - Proceedings of the 8th Annual Western Interstate Snow Survey Conference PB - American Geophysical Union, Transactions, Part III-B: CY - Seattle, Washington UR - sites/westernsnowconference.org/PDFs/1940aElges.pdf ER - TY - Generic T1 - Unit -- hydrograph T2 - 8th Annual Western Interstate Snow Survey Conference Y1 - 1940 A1 - Elliott, R.H. A1 - Sherman, L.K. KW - Flood control prediction, Snowmelt and runoff, Unit hydrograph AB - The application of the Unit-Hydrograph method of forecasting floods from rainfall is described. The same basic principals are suggested for designing a procedure of forecasting floods from snow covered portions of the river basin. The Unit-Hydrograph procedure involves searching the several snowmelt factors, to establish the unit of time with the unit of snowmelt resulting in a unit of runoff volume. These units are applied to the area of the basin involved. No sample calculation is presented. JF - 8th Annual Western Interstate Snow Survey Conference T3 - Proceedings of the 8th Annual Western Interstate Snow Survey Conference PB - American Geophysical Union, Transactions, Part III-B: CY - Seattle, Washington UR - sites/westernsnowconference.org/PDFs/1940aElliott.pdf ER - TY - Generic T1 - Relation of fall streamflow to spring runoff T2 - 7th Annual Western Interstate Snow Survey Conference Y1 - 1939 A1 - Eagle, H.C. KW - Fall precipitation, Fall streamflow, Water supply forecasting AB - Precipitation measurements and snow survey data together with fall runoff (mean October, as an index to soil priming and groundwater conditions) are used in water supply forecasting procedures, for the Yellowstone River, Montana. Data exhibited in the table form the basis for a regression equation. Results of actual and forecasted values are shown on a graph. October runoff is weighted by cut-and-try procedure, which reduces the forecast error. Winter and spring precipitation are also adjusted. These adjustments are show in tabulations and are also plotted on a histogram to show the effects of the adjustments. JF - 7th Annual Western Interstate Snow Survey Conference T3 - Proceedings of the 7th Annual Western Interstate Snow Survey Conference PB - American Geophysical Union, Transactions, Part I: CY - Spokane, Washington ER - TY - Generic T1 - Applying the Chatillon iso-elastic springs to the Mount Rose spring balance T2 - 6th Annual Western Interstate Snow Survey Conference Y1 - 1938 A1 - Elges, C. KW - Snow scales spring balance, Snow survey equipment AB - Temperature variations affecting the elasticity, creep and hysteresis of the metal of the springs and deviations from the shape in the stresses and transmitting machinery cause inaccuracies in spring scales. A new spring developed by J. Chatillon and Sons, made of an alloy called Iso-Elastic Metal eliminated the effects of temperature changes in the spring. The creep at stress of 60,000 lbs/sq in was reduced to less than 0.02% in deflection. The hysteresis was not over 0.02-0.04% of the full load deflection. A linear relationship of spring between load and deflection was obtained by using wire coiled with the axis of the wire parallel to the axis of the helix. Iso-Elastic springs were used in a Chatillon spring scale weighing 6 lbs, 5 oz. which gave an accuracy of 99.92%. A Mount Rose type of spring balance scale weighing 2 lbs. 12 oz. was constructed using Iso-Elastic springs. Further development of the scales is necessary to reduce it in size and weight before it can be used for snow surveys. JF - 6th Annual Western Interstate Snow Survey Conference T3 - Proceedings of the 6th Annual Western Interstate Snow Survey Conference PB - American Geophysical Union, Transactions, Part I: CY - Los Angeles, California ER - TY - Generic T1 - Improvements in the methods of forecasting streamflow T2 - 6th Annual Western Interstate Snow Survey Conference Y1 - 1938 A1 - Elges, C. KW - Water supply forecasting, Water supply forecasting methods AB - Various methods of forecasting streamflow from snow surveys are reviewed. Data for Lamoille Creek, Nevada in 1938 are used to compare 3 different systems of obtaining average water content of the snow cover. Boardman’s Percent Normal System, and the direct curve method of computing the average water content are illustrated. The direct method retains all the desirable features of the percentage system yet eliminates computing normals and percentages.Discussions are presented by Fred H. Paget, J.E. Phillips, James C. Marr, and R.D. Goodrige. JF - 6th Annual Western Interstate Snow Survey Conference T3 - Proceedings of the 6th Annual Western Interstate Snow Survey Conference PB - American Geophysical Union, Transactions, Part I: CY - Los Angeles, California ER - TY - Generic T1 - Possible research projects in snow surveying and stream flow forecasting in the Western States T2 - 5th Annual Western Interstate Snow Survey Conference Y1 - 1937 A1 - Elges, C. KW - Snow research program AB - Recommendations are made for the establishment of one or more mountain meteorological stations to study the factors involved in the occurrences and ablation of snow and snow melt runoff, mainly temperature, snow accumulation, precipitation at the source of the runoff. Evaporation as effected by chinook winds east of the Continental Divide and Sierra, should be investigated. Other recommendations include snow courses of approximately 20 measurements with adequate cross courses, and improvements in forecasting, runoff, lake or reservoir elevations and the effects of forest fires and added protection of protecting the local environment around a snow course. JF - 5th Annual Western Interstate Snow Survey Conference T3 - Proceedings of the 5th Annual Western Interstate Snow Survey Conference PB - American Geophysical Union, Transactions, Part II: CY - Denver, Colorado ER - TY - Generic T1 - Snow cover conditions for winter sports in the Western States T2 - 5th Annual Western Interstate Snow Survey Conference Y1 - 1937 A1 - Ewing, P.A. KW - Winter sports reporting, Winter sports snow conditions AB - Winter sports snow conditions terminology has been confused by colloquialisms, terms vary with the number of reports. An attempt is made by creating a symposium, bringing together reporters and knowledgeable ski instructors and experts to set up a set of terms to be used and definitions. Such a listing is exhibited. In the Western Unites Stated, some 2,000,000 people are taking advantage of the winter sports radio broadcasts and newspaper releases. With the cooperation of the National Parks, U.S. Forest, State Parks, and many other companies and private ski tower operators, the reporting program to this ever-growing business is progressing. JF - 5th Annual Western Interstate Snow Survey Conference T3 - Proceedings of the 5th Annual Western Interstate Snow Survey Conference PB - American Geophysical Union, Transactions, Part II: CY - Davis, California ER - TY - Generic T1 - Lamoille creek basin normals: a case in which extension of normals by comparison with precipitation-data proved more valuable by comparison with another stream T2 - 4th Annual Western Interstate Snow Survey Conference Y1 - 1936 A1 - Elges, C. KW - Snow survey normals, Water supply forecasting AB - An example is given of extended snow cover normals by comparison with precipitation data for a small basin in Eastern Nevada. The expansion was accomplished by comparing the snow cover and an elevation of 7400 ft on March 1 with Nov.-Feb. precipitation. In this case the expansion from precipitation data yielded better results than could be expected by comparison to the stream flow data of the Humboldt River. Tabulation of data and a graph illustrates the results with detailed text analysis. JF - 4th Annual Western Interstate Snow Survey Conference T3 - Proceedings of the 4th Annual Western Interstate Snow Survey Conference PB - American Geophysical Union, Transactions, Part II: CY - Pasadena, California ER - TY - Generic T1 - Improvements in forecasting the flow of the Humboldt River, Nevada T2 - 2nd Annual Western Interstate Snow Survey Conference Y1 - 1934 A1 - Elges, C. KW - Water supply forecasting AB -

A description of the revised system of stream-flow forecasting for the Humboldt River in North Central Nevada is presented. The lack of existing records of the streamflow and snow survey data and other meteorological factors in the Humboldt Mountains has hampered accurate results of forecasting. The isolation of the river basin surrounded by wide expanses of dry desert lands poses a major problem to locate correlation data with streamflow. The gageing stations are far downstream and below many diversions for irrigation that are also not measured. A list of six (6) recommendations for new stations to measure the several factors necessary for better forecasting.

JF - 2nd Annual Western Interstate Snow Survey Conference T3 - Proceedings of the 2nd Annual Western Interstate Snow Survey Conference PB - American Geophysical Union, Transactions 15: CY - Berkeley, California ER -