摘要:

This paper demonstrates the application of a groundwater quantity and quality model to large‐scale groundwater basin management. The model employs a finite difference formulation of groundwater flow to compute the groundwater elevations at the node points of a two‐dimensional homogeneous aquifer. A compatible groundwater quality model uses a control volume or mass balance approach to compute the concentration of a conservative constituent at each node. The model was calibrated to a 1200 mi2groundwater basin in central California. Over 300 nodes were used in a symmetrical network. Water and waste water management alternatives are input to the model: amounts of pumping, natural infiltration, surface water use, and waste water recharge at selected future dates are specified. The impact of five alternatives on the groundwater basin over a simulated 45 years of operation is shown. Thus the evaluation of alternative water resource management schemes was based, in part, on model performance. This type of groundwater model shows promise as an integral tool in planning and managing the development of groundwater bas

ISSN:0043-1397    

DOI:10.1029/WR008i001p00231

年代:1972

数据来源: WILEY

摘要:

There is an observable trend toward the use of subsurface reservoirs for storing different fluids. This trend is rapidly changing the picture of investigative programing for evaluating such reservoirs. Historically, studies were focused chiefly on the consequences of the withdrawal of fluids. Projecting the changing emphasis toward the broader use of storage capacity, one should expect problems arising from the injection of fluids to attain a similar significance. The injection of fluids with dissolved substances of kinds and in concentrations incompatible with the rocks can cause thermal and chemical stresses in addition to the more prosaic pressure stress. All three types of stress can produce changes: (1) in the reservoir, (2) of the land surface, and (3) of structures on the land surface. Subsidence, seismic response, water quality degradation, and plugging of the pore space are already recognized as undesirable consequences of withdrawal and injection. Earth scientists are not yet fully cognizant of the need to define such responses in the subsurface quantitatively, and therefore planners cannot become fully aware of the total cost of various alternatives for using the sub‐surface. Hopefully, research emphasis and data collection practices will be altered to answer successfully the new and more complex question

ISSN:0043-1397    

DOI:10.1029/WR008i001p00238

年代:1972

数据来源: WILEY

摘要:

The precipitation committee organized a symposium given at the AGU National Fall Meeting in December 1969. The session contained seven invited papers:1. Snow Measurement Predicament.2. Weight Capacity Requirements for Precipitation Measurements in the Wasatch Mountains.3. Precipitation Telemetry in Mountainous Areas.4. Optimum Gaging of Thunderstorm Rainfall in Southeastern Arizona.5. Rainfall Intensity‐Duration‐FrequencyRelations for the Wasatch Mountains of Northern Utah.6. Measurement of Atmospheric and Ground Level Precipitation.7. Variance Spectra of Short Duration Rainfall in Time and Sp

ISSN:0043-1397    

DOI:10.1029/WR008i001p00243

年代:1972

数据来源: WILEY

摘要:

Increased interest in snow and snowmelt runoff has resulted in the need for a better knowledge of snowfall and the water equivalent of snow cover. Present measuring methods have proven valuable for seasonal runoff prediction and other water management requirements in major snow areas. However, more accurate estimates of the actual snowfall and the average areal snow cover are required for detailed water budget and water use studies and for input for the conceptual forecasting models now being developed. The limitations of present measuring systems are analyzed, and guidelines for their usefulness as indices are presented. The basic problems involved in determining more representative values are discussed, and suggestions are given for methods to improve measurements.

ISSN:0043-1397    

DOI:10.1029/WR008i001p00244

年代:1972

数据来源: WILEY

摘要:

The reasonable readout resolution and the accuracy of the data from the telemetering precipitation measurement stations of the Wasatch Weather Modification Project are inversely related to the assigned measurement range. Consequently, provision for precipitation amounts much in excess of the amounts actually experienced results in an unnecessary loss of information. The results of this study indicate that for the winter season and insofar as the liquid water equivalent is concerned only a few locations need the 70‐inch capacity; 60 inches will suffice for most high altitude‐high yield stations; 36 inches is ample for low altitude‐high yield stations; 20 inches is more than adequate for low altitude‐low yield stations. Volume capacity requirements are somewhat higher because of the delay of melting in the collect

ISSN:0043-1397    

DOI:10.1029/WR008i001p00249

年代:1972

数据来源: WILEY

摘要:

A battery‐operated telemetry system having high resolution and accuracy has been developed at the Utah Water Research Laboratory. The sysem is used for telemetering precipitation data from 45 remote mountain sites in the Wasatch and Uinta mountain ranges. At selected sites temperature, wind, and the water content of snow have also been telemetered. The use of a unique pick‐off sensor on the transducer also permits the system to be readily adapted to telemeter information from many recording‐type instruments such as a baro

ISSN:0043-1397    

DOI:10.1029/WR008i001p00255

年代:1972

数据来源: WILEY

摘要:

About 70% of the annual precipitation on the Walnut Gulch Experimental Watershed in southeastern Arizona occurs as thunderstorm rainfall during the 3‐month period from July through September. The summer thunderstorms produce high intensity, short duration rains of limited areal extent. Records from long‐term stations give good estimates of the average annual and seasonal precipitation for a region, but networks of recording gages are necessary to describe individual storms and seasonal rainfall on finite watersheds. The optimum rain gage density varies inversely with watershed size and directly with the required accuracy. For example, to correlate rainfall and runoff, a 1‐mi2watershed with a length‐width ratio of 4 requires a network of three recording rain gages. For watersheds of approximately 120 acres or less, the optimum network for rainfall‐runoff correlation is one recording rain gage. Generally, the number of gages required per unit area decreases as the watershed size increases up to about 10 mi2. A network of gages located at 1.5‐mile intervals is necessary to correlate adequately the thunderstorm rainfall and runoff for watersheds of 10

ISSN:0043-1397    

DOI:10.1029/WR008i001p00259

年代:1972

数据来源: WILEY

摘要:

The results of data analyses for 25 precipitation intensity stations in central and north central Utah at altitudes of 4350–10,150 feet are presented. All data were collected from May 1 to October 31. Each station has 10 or more years of record; one station has 30 years of record. Analyses were made of (1) record consistency, (2) definition of local precipitation zones, (3) intensity‐duration‐frequency characteristics, (4) 24‐hour depths, (5) monthly depths and number of storms, (6) storm occurrence by hour of the day, and (7) storm occurrence by storm duration. The precipitation zone at 6500–8000 feet altitude is expected to receive the greatest rainfall intensities. There is a trend toward reduced intensities with increasing elevation, but the trend is not uniform. However, those precipitation zones receiving the greatest intensity of rainfall do not coincide with those zones receiving the greatest depth of rainfall. Rainfall depth generally increases with altitude, but on one study area the zone of greatest depth was not the highest zone. There is a marked difference between the two study areas with respect to the distribution of storm occurrence by hour. This difference is attributed to differences in storm type and in the principal source of summer moisture. Average storm length varies inversely with

ISSN:0043-1397    

DOI:10.1029/WR008i001p00266

年代:1972

数据来源: WILEY

摘要:

Variance spectra for rainfall amounts were determined for time series composed of 5‐, 10‐, 30‐, and 60‐minute rainfalls from selected storms at individual gages in dense networks. Space series were developed from rainfalls at fixed intervals along transects in the direction of storm movement. The areas considered in the analysis range in size from less than 1 mi2to 1000 mi2and cover several rainfall regimes. Diagrams display such relationships as the correlation coefficient as a function of distance between rain gages and time series duration, the autocorrelation coefficient as a function of lag and time series duration, and the power spectral density as a function of wave number for both the time and the space

ISSN:0043-1397    

DOI:10.1029/WR008i001p00272-02

年代:1972

数据来源: WILEY