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This dataset contains ascii text files of latitude, longitude, and water depth data which were collected using a pole-mounted multibeam echosounder system from the R/V Ukpik in July-August, 2021. Dr. Emily Eidam was the team lead and Dan Duncan was the multibeam operator. The data were collected along discrete tracklines across Harrison Bay. The general study was seaward of the Colville Delta between Cape Halkett to the west and Oliktok Point to the east, with a maximum seaward extent to water depths of approximately 30 meters (m) (about half to three-quarters of the way across the shelf from the shoreline). The dataset also contains a netcdf file of bathymetric change which was computed as the difference between the combined 2021 and 2022 data contained in this archive and a 1950s dataset which was recently corrected and is publicly available through Zimmerman et al., 2022 (doi.org/10.1016/j.csr.2022.104745). The multibeam data provide information about a rich diversity of seabed features including large and small ice-keel scours, sand waves, strudel scour pits, and unusual scoured substrates. A detailed description of these datasets is provided in an in-preparation manuscript (Eidam et al., Seafloor sediments and morphologic features of Harrison Bay in the Alaskan Beaufort Sea). The bathymetric change data illustrates erosion of the inner and inner-middle shelf over the past ~70 years, including erosion of up to ~3 m near Cape Halkett and on the Colville Delta front. These changes are addressed in detail in Heath, 2024 (Oregon State University Master of Science Thesis, "Sedimentation and Erosion on an Arctic Continental Shelf: Harrison Bay and Colville River Delta, Alaska"). 

Sediments covering Arctic continental shelves are uniquely impacted by ice processes. Delivery of sediments is generally limited to the summer, when rivers are ice free, permafrost bluffs are thawing, and sea ice is undergoing its seasonal retreat. Once delivered to the coastal zone, sediments follow complex pathways to their final depocenters—for example, fluvial sediments may experience enhanced seaward advection in the spring due to routing under nearshore sea ice; during the open-water season, boundary-layer transport may be altered by strong stratification in the ocean due to ice melt; during the fall storm season, sediments may be entrained into sea ice through the production of anchor ice and frazil; and in the winter, large ice keels more than 20 m tall plow the seafloor (sometimes to seabed depths of 1–2 m), creating a type of physical mixing that dwarfs the decimeter-scale mixing from bioturbation observed in lower-latitude shelf systems. This review summarizes the work done on subtidal sediment dynamics over the last 50 years in Arctic shelf systems backed by soft-sediment coastlines and suggests directions for future sediment studies in a changing Arctic. Reduced sea ice, increased wave energy, and increased sediment supply from bluffs (and possibly rivers) will likely alter marine sediment dynamics in the Arctic now and into the future. 

In Fall of 2024, central Florida was impacted by Hurricane Helene (landfall in Perry, FL as a Cat 4 hurricane on Sept 27) and by Hurricane Milton (landfall in Siesta Key, FL as Cat 3 on Oct 9). The hurricanes led to damages of an estimated value > $200billion. The Nearshore Extreme Events Reconnaissance Association (NEER) and the Geotechnical Extreme Events Reconnaissance Association (GEER) represented by their members from more than 10 academic institutions, federal agencies, and industry and supported by technical staff from the NHERI RAPID facility and the UF Center for Coastal Solutions initiated on Sept 23 a data collection effort that included pre-, during-, and post-storm multi-disciplinary data collections efforts. The field data collection effort was concluded on Nov 22. Data includes hydraulic information on storm surge, waves, and currents, topographic and bathymetric data sets, terrestrial and seabed mapping, and geotechnical site characterization including in-situ testing, sediment sampling, and seismic testing. Data was collected in four focus areas in Florida (Cedar Key; Horseshoe Beach; Midnight Pass and Milton Pass, both near Venice) and observational data and limited data products were collected in other areas in Florida including Orchid, Ponte Vedra, Suwannee, Panama City, and others. Data is organized by site (four primary sites and others); data collection phase with respect to the two hurricanes; and instruments or data collection method. This work included support from both the UF Center for Coastal Solutions and the NHERI RAPID facility. 

This project documents flood-induced geo-structural damage and geomorphological change due to the flooding in the Ahr Valley in Germany during the 2021 Western European floods. It contains detailed, multi-instrument measurements both within the river channel and along the river banks at five carefully selected sites. 

This dataset comprises the geotechnical data from a series of surveys conducted in Harrison Bay, Alaska in July/August of 2021 and 2021. The contribution of this specific dataset to the overall project goals was connecting geotechnical sediment properties to erodibility parameters in an Arctic coastal environment. During the 2021 survey, geotechnical sediment properties from a portable-free fall penetrometer (PFFP) were related to physical sampling to develop a regional sediment classification scheme, and the data collected during the 2022 survey aimed to connect the results from the previous year to laboratory-based erodibility parameters from the Jet Erosion Test (JET), which was conducted on gravity core samples taken from the site. The attached repository contains both raw and processed data, and the specifics of the file structure can be found in the readMe.txt file.