EK80 Water Column Sonar Data Collected During PC2406_Leg1

The Ecosystem Monitoring surveys contribute to stock assessments, protected species assessments, ecosystem assessments, and climate assessments. As such, the surveys are multi-objective. Ichthyoplankton and hydrographic data are collected for stock assessments. A range of ecosystem observations are made, from nutrients and ocean acidification to marine mammals, and these measurements are used in NEFSC ecosystem assessment products. The ocean acidification and hydrographic measurements are incorporated into the regionâs climate assessments. This survey is multidisciplinary and as such will integrate all these operations. The cruise plan will evolve with input from scientists as well as the officers and crew of Pisces. A post-cruise meeting will focus on lessons learned and improvements to make for subsequent

The survey consists of 120 random-stratified and 42 fixed stations in the Middle Atlantic Bight, Southern New England, Georges Bank and the Gulf of Maine (Figure 1). These stations are distributed at varying distances, and as such there is no fixed expectation of number to be covered each day. Rather, the progress of the survey will depend on transit time, sea state, and water depth of the stations, with deeper stations requiring more time to complete operations. Some stations will also have more complex
operations scheduled, such as a water cast and a bongo tow, which will increase the amount of time spent on-station.
All station locations and a detailed cruise track will be provided to the vessel prior to sailing to allow the navigation officer ample time to load this information into the navigation systems. The Mid-Atlantic Bight, Southern New England, Georges Bank, and western Gulf of Maine stations will be prioritized for sampling. A cruise track will be planned to best sample these regions. All of this is dependent on weather conditions and may be altered by the vessel command in coordination with the Chief Scientist. The Commanding Officer and Chief Scientist will jointly modify the track during the cruise as weather conditions and time constraints vary to best achieve the cruise objectives. Highest reasonable cruising speeds should be employed to improve the potential to complete the cruise missions.
Supplemental sampling may be added to the cruise track if essential cruise objectives will be completed before the scheduled return date. Potential areas of interest include the central Gulf of Maine, warm core eddies along the northeast shelf-break, and regions near wind energy lease areas. The Commanding Officer and Chief Scientist will jointly modify the track during the cruise to add supplemental science sampling if cruise objectives are met and the cruise can continue to provide valuable science for NOAA.
The deployments of the Seabird 19+ (with and without bongos) and 911+ CTD units will use the two hydrographic winches and a CTD computer located in the dry lab.
(A) Random Plankton Stations: A Seabird CTD profiler attached to an array of two bongo nets (61 and 20 cm diameters) will be deployed at 120 randomly selected stations, time permitting (Figure 2). In addition, a Seabird CTD 19+ profiler will be deployed alone to collect seawater for salinity calibrations, at deep stations (>205 m), following the bongo tow, which only goes to a maximum depth of 200 m depth
(B) Fixed Oceanography Stations: A Seabird 911+ CTD will be deployed on a rosette frame with a carousel water sampling system (SBE32) and 12 10-liter Niskin bottles at 35 of the fixed stations (Figure 3). This package will collect profiles of water temperature, salinity, chlorophyll-a and oxygen levels to within 5 meters of the bottom, or to a maximum depth of 500 meters. Water samples collected by the Niskin sampling bottles at multiple depths along the upcast will be processed for nutrients, dissolved inorganic carbon (DIC) analysis, a water filtered for chlorophyll analysis. A sub-set of stations, approximately 18, will also conduct a bongo tow.
(C) Fixed Plankton Stations: A Seabird CTD profiler attached to an array of two bongo nets (61 and 20 cm diameters) will be deployed at five Bureau of Ocean Energy Management Wind Energy Areas in the southern New England Region adjacent to Nantucket Shoals. These five stations will be sampled after departing port and on the return to port (Figure 2).
(D) Supplemental Plankton Stations: Non-random bongo stations may be added along the track line to collect samples for use in energy density estimates of plankton for foraging right whales and collections of larval fish.
(E) Optics and Remote Sensing: Satellite remote sensing calibration data will be collected using several instruments. A bio-optical flow through package (Figure 4) to measure optical properties (absorption, backscattering, T, S and fluorometry) and two IFCBs (Figure 5) that characterizes the phytoplankton community. Continuous above-water radiometry will be collected from the bow of the ship (DALEC). A profiling radiometer over-the-side deployment hand-cast will be performed once a day at satellite overpass time (1000 â 1400), weather dependent (SOP Appendix E).
(F) Acoustic Survey Operations: EK-80 operations will be conducted continuously throughout the cruise track at the highest safe transit speed possible, and during scientific gear deployments. The retractable keel should be deployed to the intermediate depth to allow for the best acoustic data possible.
(G) Acoustic Doppler Current Profiler (ADCP): ADCP will be running and logging data throughout the cruise.
(H) Scientific Computer System (SCS): The ships SCS system is a PC-based server, which continuously collects and distributes scientific data from various navigational, oceanographic, meteorological, and sampling sensors throughout the cruise. Date and time for data collections from computers, instrumentation, and logsheets recording will be synchronized using the vesselâs GPS master clock and Dimension IV software. The NEFSC and Shipâs ET are responsible for ensuring data collection and logging. The Shipâs CST/ST are responsible for ensuring that all requested data is transferred to the provided drive and given to the NEFSCâs Chief Scientist or their CTD technician.
(I) Flow-Thru Seawater system: Flow-thru system should be cleaned prior to cruise including a freshwater flush. The system should run during the entire cruise and log the data. The flow-thru seawater system should be turned on as soon as possible after leaving the pier and start logging data. The TSG should record salinity, temperature, density. Ability to draw a very small amounts of water from the system for Imaging FlowCytoBot units and a flowthrough bio-optical package is also required.
(A) Seabird and marine mammal visual observations: Visual observations will be made during daylight hours by two observers rotating on a two hour schedule from the flying bridge. Observations may be made from the bridge during inclement weather. The flying bridge should have 110 VAC available for the observersâ laptops. The ship should supply a radio for the observerâs communications with the bridge and watch chief and an overhead canopy if available. The science party will supply a platform, desk, and deck chairs for the observers to use as an observing area.
(a) Observer Protocols:
(i) Observers will be on duty during daylight hours, approximately sunrise to sunset, on two hour shift rotations.
(ii) Observers will check in with the bridge at the start of daily observations, and when ending observations for the day.
(iii) Bridge should communicate with the observers when:
1) At the end of a designated transect line, or arrival at a sampling station, and then upon resuming the survey.
2) At a significant course change (15 degrees or greater).
3) At potential breaks in effort due to poor environmental conditions such as fog, rain, squalls, etc.
a) Bridge should provide ample warning to staff on flying bridge before sounding fog horn.
4) When the shipâs speed falls below 6kts and upon reaching 8kts.
(iv) Observers should communicate mammal sightings that may require change in ship speed or course.
1) This generally includes animals within 800 â 1000 m forward of the beam.
a) Observers can report other sightings of general interest.
b) Slowing or stopping the vessel is at the discretion of the Chief Scientist. For PC2406, we generally want to stay on course and speed except for right whale sightings.
2) Right whale sightings should be reported to the Chief Scientist or Watch Chief.
a) Observers will attempt to take pictures of right whales for use in individual identification.
b) Plankton sampling may be taken near feeding right whales at the discretion on the Chief Scientist or Watch Chief.

Tags: acoustic scattering, acoustic sounders, aquatic ecosystems, aquatic sciences, bathymetry, bathymetry/seafloor topography, benthic, biosphere, doc/noaa/nesdis/ncei, doc/noaa/nesdis/ngdc, earth science, ecosystems, fisheries, in situ/laboratory instruments, marine ecosystems, national centers for environmental information, national geophysical data center, nesdis, noaa, north atlantic ocean, ocean acoustics, oceans, pelagic, profilers/sounders, seafloor topography, u.s. department of commerce, vertical location, water column, water column mapping system, wcms
Organization: National Oceanic and Atmospheric Administration, Department of Commerce