Hindcasting of decadal-timescale estuarine bathymetric change with a tidal-timescale model

This paper is not subject to U.S. copyright. The definitive version was published in Journal of Geophysical Research 114 (2009): F04019, doi:10.1029/2008JF001191.Hindcasting decadal-timescale bathymetric change in estuaries is prone to error due to limited data for initial conditions, boundary forcing, and calibration; computational limitations further hinder efforts. We developed and calibrated a tidal-timescale model to bathymetric change in Suisun Bay, California, over the 1867–1887 period. A general, multiple-timescale calibration ensured robustness over all timescales; two input reduction methods, the morphological hydrograph and the morphological acceleration factor, were applied at the decadal timescale. The model was calibrated to net bathymetric change in the entire basin; average error for bathymetric change over individual depth ranges was 37%. On a model cell-by-cell basis, performance for spatial amplitude correlation was poor over the majority of the domain, though spatial phase correlation was better, with 61% of the domain correctly indicated as erosional or depositional. Poor agreement was likely caused by the specification of initial bed composition, which was unknown during the 1867–1887 period. Cross-sectional bathymetric change between channels and flats, driven primarily by wind wave resuspension, was modeled with higher skill than longitudinal change, which is driven in part by gravitational circulation. The accelerated response of depth may have prevented gravitational circulation from being represented properly. As performance criteria became more stringent in a spatial sense, the error of the model increased. While these methods are useful for estimating basin-scale sedimentation changes, they may not be suitable for predicting specific locations of erosion or deposition. They do, however, provide a foundation for realistic estuarine geomorphic modeling applications.This study was supported by the U.S. Geological Survey’s Priority Ecosystems Science program, CALFED Bay/Delta Program, and the University of California Center for Water Resources. Use of ROMS and the CSTMS was supported by the U.S. Geological Survey, with assistance from John Warner

Discontinuous hindcast simulations of estuarine bathymetric change : a case study from Suisun Bay, California

This paper is not subject to U.S. copyright. The definitive version was published in Estuarine, Coastal and Shelf Science 93 (2011): 142-150, doi:10.1016/j.ecss.2011.04.004.Simulations of estuarine bathymetric change over decadal timescales require methods for idealization and reduction of forcing data and boundary conditions. Continuous simulations are hampered by computational and data limitations and results are rarely evaluated with observed bathymetric change data. Bathymetric change data for Suisun Bay, California span the 1867–1990 period with five bathymetric surveys during that period. The four periods of bathymetric change were modeled using a coupled hydrodynamic-sediment transport model operated at the tidal-timescale. The efficacy of idealization techniques was investigated by discontinuously simulating the four periods. The 1867–1887 period, used for calibration of wave energy and sediment parameters, was modeled with an average error of 37% while the remaining periods were modeled with error ranging from 23% to 121%. Variation in post-calibration performance is attributed to temporally variable sediment parameters and lack of bathymetric and configuration data for portions of Suisun Bay and the Delta. Modifying seaward sediment delivery and bed composition resulted in large performance increases for post-calibration periods suggesting that continuous simulation with constant parameters is unrealistic. Idealization techniques which accelerate morphological change should therefore be used with caution in estuaries where parameters may change on sub-decadal timescales. This study highlights the utility and shortcomings of estuarine geomorphic models for estimating past changes in forcing mechanisms such as sediment supply and bed composition. The results further stress the inherent difficulty of simulating estuarine changes over decadal timescales due to changes in configuration, benthic composition, and anthropogenic forcing such as dredging and channelization.This study was supported by the U.S Geological Survey’s Priority Ecosystems Science program, CALFED Bay/Delta Program, and the University of California Center forWater Resources

Motor Performance and Quality of Life in a Community Exercise Program for Parkinson Disease

We investigated the effect of a comprehensive community program composed of exercise, mindfulness practice, and education on motor function and quality of life in individuals with Parkinson disease (PD). Thirty-six participants completed physical and quality-of-life assessments independently at baseline and 12 months. Physical assessments showed stability or improvement in functional mobility, integrated strength, and walking ability over the 1-year interval. PDQ-39 measures showed improvement in 6 of 8 indices: mobility, activities of daily living, emotional well-being, stigma reduction, social support, and bodily discomfort. Our results demonstrate the effectiveness of exercise, mindfulness, and education in community and group settings

Building governance and energy efficiency: Mapping the interdisciplinary challenge

Improving the energy efficiency of multi-owned properties (MoPs)—commonly known as apartment or condominium buildings—is central to the achievement of European energy targets. However, little work to date has focused on how to facilitate retrofit in this context. Drawing on interdisciplinary Social Sciences and Humanities expertise in academia, policy and practice, this chapter posits that decision-making processes within MoPs might provide a key to the retrofit challenge. Existing theories or models of decision-making, applied in the MoP context, might help to explain how collective retrofit decisions are taken—or overlooked. Insights from case studies and practitioners are also key. Theories of change might then be employed to develop strategies to facilitate positive retrofit decisions. The chapter maps the issues and sets an agenda for further interdisciplinary research in this novel area

Is the Risk for Sexual Revictimization Cumulative? A Prospective Examination

Introduction: Sexual abuse during childhood is associated with risk for sexual assault as an adult, known as revictimization. Although multiple experiences of sexual assault in adulthood are also common, it is unclear how risk trajectories might continue to evolve in emerging adulthood, defined as ages 18 to 25. Clarifying risk trajectories is important to inform the development of targeted risk reduction interventions. To fill this gap, we examined cumulative risk for sexual assault in emerging adult women following multiple experiences of childhood sexual abuse (CSA) and adulthood sexual assault (ASA). Methods: Women (n = 447; aged 18–25 years at enrollment) completed behaviorally specific assessments of unwanted sexual experiences at up to nine time points across 3 years. Logistic regression was used to predict any sexual assault during the 3-year period as a function of victimization history at baseline. A multilevel logistic regression analysis among ASA survivors was then used to determine whether each successive ASA increased risk for further victimization. Results: Extending prior research, findings revealed that the risk for sexual assault during the 3-year study was greater for women reporting more prior experiences of CSA and ASA. Unexpectedly, each ASA increased the risk for a subsequent ASA to a lesser extent among women with more experiences of CSA. Conclusions: Findings suggest that the risk for sexual revictimization can be cumulative, but that risk does not increase indefinitely. Future research should investigate the points at which survivors of multiple assaults may begin to experience a decreased risk for later assaults, as well as the factors associated with change in risk status (e.g., removal from violent environments or relationships, changes in institutional policies). Such research could inform intervention targets