Woods Hole Oceanographic Institution
Cruise Planning Synopsis
view revisions | |
KN200-02 | |
Ship | |
R/V Knorr | |
Cruise Party | |
Dave Hebert: Chief Scientist, Principal Investigator GSO, University of Rhode Island 215 South Ferry Road Narragansett, RI USA 02882 +1 902 426 1216 hebert@gso.uri.edu |
Departure: Feb 27, 2011 | |
Halifax | |
Arrival: Apr 4, 2011 | |
Halifax | |
Operations Area | |
northeast of Flemish Cap. off Newfoundland, Canada | |
Lat/Lon: 50° 0.0′ N / 43° 0.0′ W | |
Depth Range: 100 / 2000 | |
Will the vessel be operating within 200 NM of a foreign country? | Canada |
Are visas or special travel documents required? | no |
Science Objectives | |
The cruise track shows the area (300 km x 300 km) of the high-resolution (HR) eddy survey. The actual location of the stations will be determine just before the cruise based on satellite altimeter data and on the transit to the first CTD station. The survey would consist of north/south transects separated by 60 km along which the velocity field, using the shipboard acoustic Doppler current profiler (ADCP) will be measured continuously to about 700 m depth. Every 50 km, a CTD cast to 1000 m will be done. Between CTD stations, an underway CTD system, operating in a tow-yo mode, will provide a CTD profile to 250 m at 10 kts every 10 minutes (3 km). XBTs will be used as backup to provide temperature profiles to 800 m halfway between normal CTD casts. These surveys will take 5.5 days each to complete. Between the two HR surveys planned, a larger scale survey to map out the surrounding eddy field and fronts, the NAC from the south and the waters leaving the eddy formation region to the east. This large scale survey will allow us to detect whether previous eddies are located in the region. If so, we can determine their structure and whether it is consistent with our hypothesis of sinking or interacting with the continental shelf and producing cyclonic eddies. CTD casts will be undertaken every degree of latitude (~110 km) along the transects which are separated by approximately 80 km. This survey will take about 12 days to complete. Underway CTD casts and XBTs will be done between the CTD stations. Time permitting, we will occupy some of the CTD stations on a repeated Canadian hydrographic line from St. John’s tp Flemish Cap. Also, as a favour to the Canadians (eg. NRCan), the multibeam will collected and provided to them. Someone from NRCan will discuss settings, etc. when the ship is in Halifax. In addition to the above work, ARGO floats and surface drifters will be deployed through the survey region. | |
Science Activities | |
The Gulf Stream travels along the eastern seaboard of the United States and Canada bringing warm water northwards. South of Newfoundland, the Gulf Stream separates into two currents, one that moves around the Grand Banks and travels northward until approximately 500N where it heads eastward across the North Atlantic. This current is known as the North Atlantic Current (NAC). In this region where the NAC turns eastward, eddies are generated on a regular basis. The mechanism for their formation and their evolution is unknown. This National Science Foundation project is to investigate these processes. Our hypothetical conceptual dynamical model of the formation, growth and separation of the NWC eddy would consist of the following processes: (1) Gradual accumulation of kinetic energy in an anticyclonic loop east of Fleming Cap related to the momentum imbalance in the NAC turning from northeast to northwest along the continental slope and splitting into two branches. (2) Shedding a warm-ÂÂÂÂÂA?core eddy after the recirculation loop increases to a size when the beta-effect is able to provide substantial self-propagation. (3) Either substantial heat loss from the ocean to the atmosphere resulting in the sinking the eddy core followed by a capping of the eddy or the eddy interacts with the shallow shelf and continental slope resulting in submesoscale cyclonic eddies generation and enhanced decay of the anticyclonic eddy. Satellite-based observations suggest that the life cycle for this process is approximately 2.5 months and the eddies, while present year round, are dominate in the spring. To address whether this model is realistic, we plan two ~30 day expeditions separated by approximately 1 month. During each cruise, two high-ÂÂÂÂÂA?resolution hydrographic surveys of the eddy region will conducted. Between the two surveys, a larger scale, coarse resolution survey of the region will be undertaken
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Additional Info | |
Pre-cruise Planning Meeting: Visit WHOI | |
Meeting Notes: Will travel to WHOI week of Jan 17th. | |
Stations: | |
Station 1 Distance: 1050 Days: 1 hr Latitude: 52° 0.0 N Longitude: 40° 50.0 W | |
Supporting documentation: | |
»Knorr_cruise_track_expanded.pdf | |
»Knorr_cruise_track.pdf |
Funding |
Funding Agency: NSF | |
Grant or contract number: OCE 1027573 |
Scientific Instrumentation for R/V Knorr |
Shipboard Equipment | |||||||||||
Bathymetry System 12 kHz | |||||||||||
Sippican XBT System (Mark 21) | |||||||||||
Bathymetry System 3.5 kHz | |||||||||||
ADCP 75 kHz | |||||||||||
Science Underway Seawater System | |||||||||||
Multibeam | |||||||||||
CTD/Water Sampling | |||||||||||
Wet Labs ECO-AFL fluorometer | |||||||||||
Wet Labs C*Star transmissometer (660nm wavelength) | |||||||||||
SBE43 oxygen sensor | |||||||||||
911+ Rosette 24-position, 10-liter bottle Rosette with dual T/C sensors | |||||||||||
Critical CTD Sensors | |||||||||||
MET Sensors | |||||||||||
Barometric Pressure | |||||||||||
Air temperature | |||||||||||
Precipitation | |||||||||||
Relative Humidity | |||||||||||
Wind speed and direction | |||||||||||
Short Wave Solar Radiation | |||||||||||
Storage Notes: | |||||||||||
Navigation | |||||||||||
Will you be using Long Base Line (LBL) navigation? | no | ||||||||||
How many nets? | 0 | ||||||||||
How many tansponders? | 0 | ||||||||||
Will you be using Doppler/GPS navigation? | yes | ||||||||||
Navigation Notes: | |||||||||||
Winches | |||||||||||
CTD Winch with .322" Electro-mechanical wire | |||||||||||
Winch Notes: | |||||||||||
Wire Notes: | |||||||||||
Standard Oceanographic Cables | |||||||||||
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Specialized Deck Equipment | |||||||||||
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Over the Side Equipment | |||||||||||
Will you be bringing any equipment (winches, blocks, etc.) that lowers instruments over the side? | yes | ||||||||||
Details: Underway CTD (uCTD) system (Ocean Sciences) This will deploy off stern / fantail. Science will bring all parts and mounts. | |||||||||||
Special Requirements | |||||||||||
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Additional Cruise Items/Activities | |||||||||||
Explosive Devices: | no | ||||||||||
Portable Air Compressors: | no | ||||||||||
Flammable Gases: | no | ||||||||||
Small Boat Operations: | no | ||||||||||
SCUBA Diving Operations: | no | ||||||||||
Hazardous Material | |||||||||||
Will hazardous material be utilized? | no | ||||||||||
Describe deployment method and quantity: | |||||||||||
Radioactive Material | |||||||||||
Radioiosotopes: | no | ||||||||||
Additional Information | |||||||||||
Is night time work anticipated on this cruise? | yes | ||||||||||
Specialized tech support (Seabeam, coring, other): Seabeam used for tech training, etc. | |||||||||||
Other required equipment and special needs: Deck mounted XBT launcher |
Checklist & Notes |
Checklist | |
U.S. Customs Form: | yes |
Diplomatic Clearance: | yes |
Date Submitted: | Nov 27, 2010 |
Date Approved: | |
Agent Information: | |
Master R/V KNORR Master, R/V Knorr Phone: (902) 468-6544 Note: Agent and WHOI contacts should be copied on all communications. It is requested that shipment information of any equipment be communicated to the Agent and to WHOI contacts. | |
Countries: | |
Canada | |
Notes: | |
4455's for gear loaded at WHOI Jan 20, 2011. | |
Isotope Use Approval: | no |
Isotope Notes: | |
SCUBA Diving: | no |
Checklist | |
SSSG Tech: | |
Some items loaded on Knorr Jan 20 2011. Rest loaded in Halifax. | |