Publications

We present the formulation, validation, and application of a nonlinear, implicit one-line model to simulate long-term (decadal and longer) shoreline change. The purpose of the implicit numerical method presented here is to allow large time steps without sacrificing model stability compared to explicit approaches, and thereby improve computational efficiency. The model uses a Jacobian...

The Cook Islands (CIs) Exclusive Economic Zone (EEZ) encompasses 1,977,000 km2 and includes the Penrhyn and Samoa basins abyssal plains where manganese nodules flourish due to the availability of prolific nucleus material, slow sedimentation rates, and strong bottom currents. A group of CIs nodules was analyzed for mineralogical and chemical composition, which include many critical...

Using older and in part flawed data, Ruff (1989) suggested that thick sediment entering the subduction zone (SZ) smooths and strengthens the trench-parallel distribution of interplate coupling. This circumstance was conjectured to favor rupture continuation and the generation of high-magnitude (≥Mw8.0) interplate thrust (IPT) earthquakes. Using larger and more accurate compilations of...

A substantial increase in fluvial sediment supply relative to transport capacity causes complex, large-magnitude changes in river and floodplain morphology downstream. Although sedimentary and geomorphic responses to sediment pulses are a fundamental part of landscape evolution, few opportunities exist to quantify those processes over field scales. We investigated the downstream effects...

Two dams on the Elwha River, Washington State, USA trapped over 20 million m3 of mud, sand, and gravel since 1927, reducing downstream sediment fluxes and contributing to erosion of the river's coastal delta. The removal of the Elwha and Glines Canyon dams, initiated in September 2011, induced massive increases in river sediment supply and provided an unprecedented opportunity to examine...

A one-dimensional numerical model describing tidally varying vertical mixing and settling was used to interpret sediment concentrations and vertical fluxes observed in the shoals of South San Francisco Bay by two acoustic Doppler velocimeters (ADVs) at elevations of 0.36 m and 0.72 m above bed. Measured sediment concentrations changed by up to 100 g m−3 over the semidiurnal tidal cycle...

In 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP), designed to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats, and geology within the 3-nautical-mile limit of California’s State Waters. The CSMP approach is to create highly detailed seafloor maps through collection, integration...

Changes in future wave climates in the tropical Pacific Ocean from global climate change are not well understood. Spatially and temporally varying waves dominate coastal morphology and ecosystem structure of the islands throughout the tropical Pacific. Waves also impact coastal infrastructure, natural and cultural resources, and coastal-related economic activities of the islands. Wave...

Understanding landscape responses to sediment supply changes constitutes a fundamental part of many problems in geomorphology, but opportunities to study such processes at field scales are rare. The phased removal of two large dams on the Elwha River, Washington, exposed 21 ± 3 million m3, or ~ 30 million tonnes (t), of sediment that had been deposited in the two former reservoirs...

One-dimensional shear-wave velocity (VS ) profiles are presented at 50 strong motion sites in New South Wales and Victoria, Australia. The VS profiles are estimated with the spectral analysis of surface waves (SASW) method. The SASW method is a noninvasive method that indirectly estimates the VS at depth from variations in the Rayleigh wave phase velocity at the surface.

From the contributions collected in this publication have emerged two important observations that have significance locally, nationally, and internationally. First, the fringing coral reef along the south coast of Moloka'i is one of the most extensive and luxuriant reefs in the eight main Hawaiian Islands. It is longer and more continuous and has denser coral cover than reefs at any of...

From changes in traditional foods to concerns of displacement from rising seas, this coastal community in the Pacific Northwest is assessing potential impacts to make decisions for their future.