Data from Three Recent Studies Released in the USGS Oceanographic Time-Series Data Collection
This article is part of the November-December 2017 issue of the Sound Waves newsletter.
One of the data sets is a follow-on to the work started in 2016 at Town Neck Beach in Sandwich, Massachusetts. The other two were collected during the summers of 2016 and 2017 in West Falmouth Harbor, Massachusetts. All three support research conducted for one or more of three projects: Coastal Model Applications and Field Measurements, Barrier Island Evolution Research, and Remote Sensing Coastal Change projects.
Oceanographic, atmospheric, and water-quality measurements at Town Neck Beach, Sandwich, Massachusetts, 2017
Town Neck Beach in Sandwich has experienced chronic erosion and is the site of ongoing unmanned aerial system (UAS) mapping and monitoring with a fixed web camera. To further assess the effects of storms, short-duration measurements of waves, tides, and overwash were collected from portable pressure sensors deployed on the beach during major winter storms on these dates: January 23-26; February 9-10; February 13-15; and March 13-15, 2017. For each storm, two pressure sensors were deployed on the beach on either side of an overwash channel. These sensors were submerged only when large waves occurred at high tide, and recorded waves and water levels at 2 Hz. An atmospheric pressure sensor was deployed about 2 meters (6 feet) above sea level to provide corrections for the other pressure sensors. One of the pressure sensors deployed in the overwash zone is shown below.
A small platform (the “nanopod”) was deployed on the seafloor north of the beach in seven meters (23 feet) of water depth between December 2016 and June 2017. This period overlapped with the storm observations, subaerial mapping, and an offshore bathymetric survey. The nanopod sensors measured waves, water level, currents, temperature, salinity, and turbidity.Data from these instruments may be accessed at: http://doi.org/10.5066/F7B27T6P.
Water-level measurements collected in West Falmouth Harbor, Massachusetts, May–October 2016
Water level was measured at two sites in West Falmouth Harbor to accurately determine tidal gradients. Tide gauges were mounted under the town-owned West Falmouth boat dock and on the private Associates dock near the mouth of the Harbor. Each gauge supported two pressure sensors mounted in a stilling well to damp wave motions. The upper sensor at each site was intended to remain above the water surface to measure atmospheric pressure; the lower sensor was intended to remain constantly submerged to measure tides and surge. The upper sensor under the boat dock was often submerged at high tide, so data from the upper sensor at the Associates dock was used to make atmospheric-pressure corrections for both sites.
Data from these instruments may be accessed at: http://doi.org/10.5066/F72Z140X.
Water-level measurements collected in West Falmouth Harbor, Massachusetts, April–June 2017
The same tide gauges were deployed at the same two sites in West Falmouth Harbor for a short period in 2017 to support subaerial and seafloor mapping of the Harbor. Based on our experience in 2016, no upper sensor was installed in the gauge under the town boat dock, and the upper sensor at the Associates dock was used to make atmospheric-pressure corrections for both sites.