Online Links:
For their outstanding logistical support in collecting the oceanographic data in this report, we thank crews of the U.S. Coast Guard Cutters White Heath and Marcus Hanna and their captains Michael Frias, Buddy Blackburn, Vernon Shay, Peter Boardman, Richard Foy, Thomas Dickey, and Paul Dupuis. The USGS and the USCG safely conducted more than 90 cruises to deploy and recover hundreds of individual instruments on about 160 separate moorings to obtain this long-term data set. Mike Bothner was chief scientist on the USCG cruises. Fran Lightsom, Mary Hastings, and Ellyn Montgomery processed the time-series data. William Strahle, Marinna Martini, and Jonathan Borden oversaw the preparation and deployment of the physical oceanographic instrumentation. Michael Casso and Rick Rendigs oversaw collection and analysis of the the sediment-trap data. Ben Gutierrez helped in the preparation of version 1 of this report. Dann Blackwood took many of the photographs in this report. Bob Barton, Dann Blackwood, Jon Borden, Michael Casso, Jessica Cote, Ray Davis, Peter Gill, Joe Newell, Carol Parmenter, Andre Ramsey, Rick Rendigs, Steve Ruane, and Richard Signell carried out the work at sea, ashore, and in the laboratory. Rick Rendigs, Dan Blackwood, Larry Ball, Steve Cross, and Ken Parolski aided in the successful recovery of several bottom tripod systems by diving when the primary recovery system failed. Donna Newman and Jennifer Martin did the html coding. Mike Connor, Ken Keay, Wendy Leo, Mike Mickelson, and Andrea Rex provided guidance from MWRA. Neil Ganju and Erin Twomey (USGS) provided helpful reviews of this report. Frank Marachi, captain of the fishing vessel Christopher Andrew, provided assistance and valuable local knowledge on a number of cruises. This research was partially supported by a Cooperative Research Agreement between the U.S. Geological Survey and the Massachusetts Water Resources Authority and by an Interagency Support Agreement with the U.S. Coast Guard.
The long-term oceanographic observations were designed to understand the transport and long-term fate of sediments and associated contaminants in Massachusetts Bay. Site LT-A is located approximately 1 km south of the new ocean outfall that began discharging treated sewage effluent from the Boston metropolitan area into Massachusetts Bay on September 6, 2000. Site LT-B is located about 28 km southeast of the new outfall in the direction of the mean current in Massachusetts Bay. The observations document sediment resuspension and transport, and seasonal and inter-annual changes in currents, hydrography, and suspended-matter concentration. They also provide observations for testing numerical models of circulation and transport. This dataset contains more than 500 files providing the observations collected from December 1989 through February 2006. The background and experimental setup are described in the open file report "Long-Term Oceanographic Observations in Massachusetts Bay, 1989-2006", on line at: http://pubs.usgs.gov/ds/74/. The locations, deployment depths, sensor type and parameters measured during the deployment are presented by site in the table displayed by the Basic Sampling Interval links (http://stellwagen.er.usgs.gov/mbay_lt-a.html and http://stellwagen.er.usgs.gov/mbay_ltb-a.html). The basic sampling interval data files are provided at the rate at which the sensor made observations- no temporal averaging, filtering or subsampling was done. Hourly averaged and low pass filtered data are also available for some files. The data files are available for download by clicking the file name in the table or via OPeNDAP and THREDDS at http://stellwagen.er.usgs.gov/opendap/MBAY_LT/ and http://stellwagen.er.usgs.gov/opendap/MBAY_LTB/.
Online Links:
Online Links:
Are there legal restrictions on access or use of the data?Access_Constraints: none
Use_Constraints:Public domain data are freely redistributable with proper metadata and source attribution. Please recognize the U.S. Geological Survey (and any cooperators you feel should be recognized) as the originator of the dataset. Biological fouling often degrades light transmission data after several months of deployment. Organisms grow on the transmissometer lenses and gradually block light transmission, which results in a gradual increase of the beam-attenuation coefficient. This drift occurs more quickly and is more severe at shallower depths. The attenuation data plots have not been corrected for biological fouling and should be interpreted with care. Salinity measured by instruments on tripods during 1989-1996, were erroneously low by as much as one practical salinity unit by the end of the 4-month deployments, due to fouling of the conductivity cells. Tripod conductivity data apparently were affected by a slow, gradual build-up of a biological film on the electrodes and also occasional sudden depositions of a significant volume of material (possibly sediments) inside the measurement volume of the conductivity cell. In June 1996 (mooring 470), Sea-Bird pumps were added to the MIDAS to flush the conductivity cell prior to making a measurement, reducing the effect of deposits on the conductivity measurements. The salinity data should be used and interpreted with care.
Neither the U.S. Government, the Department of the Interior, nor the USGS, nor any of their employees, contractors, or subcontractors, make any warranty, express or implied, nor assume any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, nor represent that its use would not infringe on privately owned rights. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the USGS in the use of these data or related materials. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
| Data format: | netCDF |
|---|---|
| Network links: |
http://stellwagen.er.usgs.gov/mbay_lt.html |
The user's computer must have software to read netCDF files or import OPeNDAP.