Simulation of Summer Rainfall Occurrence in Arizona and New Mexico
AffiliationSouthwest Watershed Research Center, Agricultural Research Service, Tucson, Arizona
Department of Hydrology and Water Resources, University of Arizona, Tucson, Arizona
KeywordsHydrology -- Arizona.
Water resources development -- Arizona.
Hydrology -- Southwestern states.
Water resources development -- Southwestern states.
Maximum probable flood
MetadataShow full item record
RightsCopyright ©, where appropriate, is held by the author.
Collection InformationThis article is part of the Hydrology and Water Resources in Arizona and the Southwest collections. Digital access to this material is made possible by the Arizona-Nevada Academy of Science and the University of Arizona Libraries. For more information about items in this collection, contact firstname.lastname@example.org.
PublisherArizona-Nevada Academy of Science
AbstractThunderstorms produce most of the annual rainfall and almost all runoff from arid and semiarid rangelands in the southwest U.S. A model was developed to be used for predicting runoff in river basins, flood plane zonings, estimating flood damage, erosion, and sediment transport, and estimating precipitation available for forage growth. This rainfall occurrence model has three parameters: elevation, latitude and longitude, and takes into account rainfall occurrence in 22 stations located in Arizona and New Mexico. From these variables, mathematical equations were developed in an effort to predict point rainfall occurrence. Estimates of the number of seasonal occurrences were used as a check of the equations within the model.
Showing items related by title, author, creator and subject.
A methodology of rainfall data analysis and stochastic rainfall/runoff synthesisJones, Allen Douglas. (The University of Arizona., 1981)Precipitation data analysis procedures are presented that allow development of the random variables of interest describing the summer and winter rainfall process in semiarid regions of the West. These procedures include programs that define the variables of event interarrival time and rainfall amount per event and a process of grouping months within these variables. A program for analyzing winter frontal storm activity is presented. Procedures are developed describing the actual distributions of the annual rainfall process. A methodology for fitting theoretical distributions to each of these actual distributions is explained. Climactic data from the Hanford Meteorology Station NW of Richland, Washington is used to develop these procedures. Results of the analysis procedures for the Hanford data are included. The results of the above analysis are incorporated into a stochastic rainfall model that includes a direct surface runoff calculation process. This runoff is calculated using the Soil Conservation Service method. The resulting stochastic model allows a study of the change in watershed practices that can greatly assist in making management decisions concerning possible water harvesting practices on western mine sites.
Comparison of rainfall sampling schemes using a calibrated Stochastic Rainfall GeneratorWelles, Edwin. (The University of Arizona., 1994)Accurate rainfall measurements are critical to river flow predictions. Areal and gauge rainfall measurements create different descriptions of the same storms. The purpose of this study is to characterize those differences. A stochastic rainfall generator was calibrated using an automatic search algorithm. Statistics describing several rainfall characteristics of interest were used in the error function. The calibrated model was then used to generate storms which were exhaustively sampled, sparsely sampled and sampled areally with 4X4 km grids. The sparsely sampled rainfall was also kriged to 4X4 km blocks. The differences between the four schemes were characterized by comparing statistics computed from each of the sampling methods. The possibility of predicting areal statistics from gauge statistics was explored. It was found that areally measured storms appeared to move more slowly, appeared larger, appeared less intense and have shallower intensity gradients.
Elucidating the role of vegetation in the initiation of rainfall-induced shallow landslides: Insights from an extreme rainfall event in the Colorado Front RangeMcGuire, Luke A.; Rengers, Francis K.; Kean, Jason W.; Coe, Jeffrey A.; Mirus, Benjamin B.; Baum, Rex L.; Godt, Jonathan W.; Univ Arizona, Dept Geosci; U.S. Geological Survey; Denver Colorado USA; U.S. Geological Survey; Denver Colorado USA; U.S. Geological Survey; Denver Colorado USA; U.S. Geological Survey; Denver Colorado USA; U.S. Geological Survey; Denver Colorado USA; U.S. Geological Survey; Denver Colorado USA; U.S. Geological Survey; Denver Colorado USA (AMER GEOPHYSICAL UNION, 2016-09-16)More than 1100 debris flows were mobilized from shallow landslides during a rainstorm from 9 to 13 September 2013 in the Colorado Front Range, with the vast majority initiating on sparsely vegetated, south facing terrain. To investigate the physical processes responsible for the observed aspect control, we made measurements of soil properties on a densely forested north facing hillslope and a grassland-dominated south facing hillslope in the Colorado Front Range and performed numerical modeling of transient changes in soil pore water pressure throughout the rainstorm. Using the numerical model, we quantitatively assessed interactions among vegetation, rainfall interception, subsurface hydrology, and slope stability. Results suggest that apparent cohesion supplied by roots was responsible for the observed connection between debris flow initiation and slope aspect. Results suggest that future climate-driven modifications to forest structure could substantially influence landslide hazards throughout the Front Range and similar water-limited environments where vegetation communities may be more susceptible to small variations in climate.