21. Modeling Transport And Sedimentation Processes In Watersheds And Coastal Regions

Predicting the rate of sediment transport is a complicated fundamental problem with many important applications. The U.S. Geological Survey is expanding fundamental and applied research towards development and testing of predictive numerical models of modern sedimentary processes in coastal watersheds, estuaries, and coastal marine environments. In particular, we are interested in developing and applying numerical models to gain better understanding the transport and sedimentation processes in two areas:

1. The removal of dams is anticipated to increase significantly during the next century, and the USGS is in a position to make a substantial contribution toward understanding the effects of these actions upon watersheds and coastal environments. The delivery of sediment through a watershed to the coastal ocean is important to both environments as it influences their physical, geological, and ecological evolution. In particular the transport and fate of different sediment size fractions is important to coastal morphology and sediment distribution, as well as related issues such as water quality. Recent progress in technology such as the development of optical and acoustical instrumentation has enabled specific investigation into the distribution and effects of sediment grain size upon sediment dynamics and system behavior. The objectives of this research are to use theory and field measurements to test and improve existing models, to advance the development of new numerical models or submodels, and to apply predictive models in regional and site studies where marine or coastal geologic processes play a key role.
2. Internal waves/tides are known to play key roles in ocean circulation, and the transport and redistribution of sediments on continental shelves, slopes, and in submarine canyons. However, the processes are poorly understood. A wealth of observational field data has been collected during USGS experiments, but field data alone are deemed inadequate to understand the complicated process of the generation, transformation, and dissipation of internal waves/tides and their impact on the transport of pollutants/nutrients/sediments. The objectives of this research will focus on developing and applying numerical models to investigate transport processes related to linear and/or nonlinear internal waves/tides/bores in the coastal ocean. We are interested in applying numerical models to gain a better understanding of the processes in general and to determine the transport patterns associated with a specific process.

Applicants with a Ph.D. and research experiences in fluid mechanics, oceanography, engineering, marine geology and sediment transport, or applied mathematics, and a strong background in numerical modeling are sought to work independently with a dynamic research group dedicated to understanding processes of pollutant, nutrient, and sediment transport on both local and regional scales. Successful candidates must have expertise in computer modeling and code development as well as experience in data processing and analysis, and field experience. Ongoing work involves the development and application of multi-scale, process based numerical models for coastal sediment transport and coastal evolution; analysis of meteorological, hydrologic, oceanographic, and geological data; application of numerical models to specific coastal systems; and analysis of model results. These modeling activities are linked to ongoing site investigations in California, Washington, South Carolina, and North Carolina.

Proposed Duty Station: Menlo Park, CA or Santa Cruz, CA

Areas of Ph.D.: Fluid mechanics, oceanography, marine geology and sediment transport, or related field

Qualifications: Applicants must meet one of the following qualifications: Research Oceanographer, Physical Scientist, Research Engineer

(This type of research is performed by those who have backgrounds for the occupations stated above. However, other titles may be applicable depending on the applicant's background, education, and research proposal. The final classification of the position will be made by the Personnel specialist.)

Research Advisor(s): Dan Hanes, (831) 427-4718, dhanes@usgs.gov; Dave Rubin, (831) 427-4736, drubin@usgs.gov; Marlene Noble, (650) 329-5486, mnoble@usgs.gov; Jingping Xu, (650) 329-5283, jpx@usgs.gov

Personnel Office contact: Marie Guillory, (650) 329-4112, guillory@usgs.gov

Summary of Opportunities