Below please find an elaboration on the KNORR cruise plan, with a timeline and figures. This was assembled with input from a number of people who provided details on their sampling plans. I welcome further comments from everyone as we continue to refine the plan.
Next Monday at 2pm Eastern time we will meet locally with the Ships Scientific Services Group and Marine Ops people to go over nuts and bolts issues about the KNORR. It will be possible for interested parties to join by conference call, though this is not a discussion of the cruise plan itself, just an opportunity to make sure we have the ship's equipment and personnel we need.
We can have a conference call on the draft cruise plan itself sometime next week.
I will soon be needing lists of the personnel joining the cruise. I understand that we do not need visas to enter the Azores.
Thanks, Ray
The basic constraints for the Knorr cruise:
Dates: Depart WH Sept. 6 – Arrive Punta Delgada, Azores, Oct. 9, 33 days at sea Distances: It is 1915 nm from Woods Hole to 25° N 38° W, about 8 days of steaming. It is 993nm from 25° N 38° W to Ponta Delgada, about 4 days of steaming. This gives our working time on site of about 21 days.
My thinking is that we can spend roughly one week deploying assets, including moorings, floats and gliders, about one week doing a small “control volume” with repeat surveys around the moorings, and about one week doing a feature survey, targeting a front or eddy identified by the satellites and models. Of course, we must always figure on some time lost to weather or chasing down the errant glider, but this is a general outline.
The moorings will require bathymetric surveys of the sites before finalizing line lengths; Tom requests that we do the surveys for all three sites first so as to give time for the mooring groups to set up. Surveying will not take long, and can be done at night; the three moorings should take no longer than three days to deploy, so long as the weather is reasonable. Obviously, some gliders, floats and drifters could be deployed during this time as well.
Steve is planning deployment of his 25 profiling floats in a 5 x 5 grid with 30 km spacing. If we steam this with a “radiator” pattern this would take about 2 days. I imagine this would be the best time to deploy the gliders, though perhaps they can self-position and get to their survey lines on their own, so could be deployed as soon as we are in the area.
The control volume around the moorings will be done with an Under Way CTD while steaming, ships ADCP, then microstructure and CTD/LADCP casts at the corners. The idea is to hit the corner stations on a 7 hour cycle, so we get four in an inertial period (~28 hrs). The corners could be the moorings or some wider square. A turbulence glider would be doing the legs, and it may be an excellent pattern for a wave glider as well. If we do this for 6 days we cover 5 inertial periods.
This would allow us about a week to chase down and survey an interesting feature (front or eddy) suggested by the satellites and models. Surveys could be stars (eddy) or butterflys (front) and the UW-CTD, CTD/LADCP and microstructure profiles will be appropriate assets.
Sept. 16: deploy North PMEL mooring
Sept. 17: deploy East PMEL mooring
Sept. 19: steam and deploy floats, surface and mixed layer drifters
Sept. 20: weather day or retrieve wayward glider or deploy mixed layer drifters
Sept. 21: structure and CTD stations at the mooring locations, ~7 hrs between stations, 4 knot steam with U/W CTD, inertial period ~28 hrs. (Figure 4).
Sept. 22: Control volume survey with U/W CTD, and micro-structure and CTD stations
Sept. 23: Control volume survey with U/W CTD, and micro-structure and CTD stations
Sept. 24: Control volume survey with U/W CTD, and micro-structure and CTD stations
Sept. 25: Control volume survey with U/W CTD, and micro-structure and CTD stations
Sept. 26: Control volume survey with U/W CTD, and micro-structure and CTD stations
Sept. 27: End box survey after 6 days (5 inertial periods), retrieve T-Glider, identify salinity frontal feature with input from satellites and models
Sept. 28: Steam to feature site, deploy surface drifter cluster, begin feature survey
Oct. 1: Feature survey with U/W CTD, and micro-structure and CTD stations
Oct. 2: Feature survey with U/W CTD, and micro-structure and CTD stations
Oct. 3: Feature survey with U/W CTD, and micro-structure and CTD stations
Oct. 4: Feature survey with U/W CTD, and micro-structure and CTD stations
Oct. 5: Check moorings, CTD stations at moorings, retrieve some gliders, begin steam for Azores
Oct. 6: Steam toward 25° N 35.5° W to deploy 7 surface drifters east of SPURS site
Oct. 7: Steam
Oct. 8: Steam
Oct. 9: Arrive Punta Delgada, Azores
Figure 1. Mooring sites with bathymetry: WHOI mooring at 24°34'N, 38°02'W PICO-East at 24°34'N, 37°49'W, PICO-North at 24°45'N, 38°02'W
Figure 2. Seaglider survey plan. 2 gliders would occupy a 140km x 140 km box centered on the WHOI mooring (red/blue), a third would perform a 50 km scale butterfly pattern around the mooring (purple).
Figure 3. Float deployment positions around central mooring. These are within the 140 x 140 km box defined by the Seagliders (plot border).
Figure 4. UnderWay CTD survey volume around moorings with microstructure and CTD/LADCP profiles at moorings.
Dates: Depart WH Sept. 6 – Arrive Punta Delgada, Azores, Oct. 9, 33 days at sea Distances: It is 1915 nm from Woods Hole to 25° N 38° W, about 8 days of steaming. It is 993nm from 25° N 38° W to Ponta Delgada, about 4 days of steaming. This gives our working time on site of about 21 days.
My thinking is that we can spend roughly one week deploying assets, including moorings, floats and gliders, about one week doing a small “control volume” with repeat surveys around the moorings, and about one week doing a feature survey, targeting a front or eddy identified by the satellites and models. Of course, we must always figure on some time lost to weather or chasing down the errant glider, but this is a general outline.
The moorings will require bathymetric surveys of the sites before finalizing line lengths; Tom requests that we do the surveys for all three sites first so as to give time for the mooring groups to set up. Surveying will not take long, and can be done at night; the three moorings should take no longer than three days to deploy, so long as the weather is reasonable. Obviously, some gliders, floats and drifters could be deployed during this time as well.
Steve is planning deployment of his 25 profiling floats in a 5 x 5 grid with 30 km spacing. If we steam this with a “radiator” pattern this would take about 2 days. I imagine this would be the best time to deploy the gliders, though perhaps they can self-position and get to their survey lines on their own, so could be deployed as soon as we are in the area.
The control volume around the moorings will be done with an Under Way CTD while steaming, ships ADCP, then microstructure and CTD/LADCP casts at the corners. The idea is to hit the corner stations on a 7 hour cycle, so we get four in an inertial period (~28 hrs). The corners could be the moorings or some wider square. A turbulence glider would be doing the legs, and it may be an excellent pattern for a wave glider as well. If we do this for 6 days we cover 5 inertial periods.
This would allow us about a week to chase down and survey an interesting feature (front or eddy) suggested by the satellites and models. Surveys could be stars (eddy) or butterflys (front) and the UW-CTD, CTD/LADCP and microstructure profiles will be appropriate assets.
Draft SPURS Cruise Timeline for KNORR, Sept. 6- Oct. 9, 2012
Sept. 6: Depart WH (~10am? high tide = 11:48 am) Steam for 25°N, 38°W Sept. 8: 1 test station (CTD/LADCP ~ 1hour)Sept. 9: 1 test station (microprofiler)
Sept. 10: 1 test station (glider, etc)
Sept. 11-13: Continue steaming with test stations as needed
Sept. 14: Deploy NW Seaglider near site. Arrive at 24° 45’N, 38° 02’W, Begin survey bottom at 3 mooring sites (Figure 1)
Sept. 15: deploy WHOI mooring
Sept. 6: Depart WH (~10am? high tide = 11:48 am) Steam for 25°N, 38°W Sept. 8: 1 test station (CTD/LADCP ~ 1hour)Sept. 9: 1 test station (microprofiler)
Sept. 10: 1 test station (glider, etc)
Sept. 11-13: Continue steaming with test stations as needed
Sept. 14: Deploy NW Seaglider near site. Arrive at 24° 45’N, 38° 02’W, Begin survey bottom at 3 mooring sites (Figure 1)
Sept. 15: deploy WHOI mooring
Sept. 16: deploy North PMEL mooring
Sept. 17: deploy East PMEL mooring
Sept. 18: steam and deploy Seagliders (Figure 2), ARGO floats, (5x5 grid for the 25 floats, 30 km spacing, ~2 days to do radiator pattern, Figure 3), Wave Gliders, 15 Surface Drifters
Sept. 19: steam and deploy floats, surface and mixed layer drifters
Sept. 20: weather day or retrieve wayward glider or deploy mixed layer drifters
Deploy T-Glider and begin control volume survey with U/W CTD, and micro-
Sept. 21: structure and CTD stations at the mooring locations, ~7 hrs between stations, 4 knot steam with U/W CTD, inertial period ~28 hrs. (Figure 4).
Sept. 22: Control volume survey with U/W CTD, and micro-structure and CTD stations
Sept. 23: Control volume survey with U/W CTD, and micro-structure and CTD stations
Sept. 24: Control volume survey with U/W CTD, and micro-structure and CTD stations
Sept. 25: Control volume survey with U/W CTD, and micro-structure and CTD stations
Sept. 26: Control volume survey with U/W CTD, and micro-structure and CTD stations
Sept. 27: End box survey after 6 days (5 inertial periods), retrieve T-Glider, identify salinity frontal feature with input from satellites and models
Sept. 28: Steam to feature site, deploy surface drifter cluster, begin feature survey
Sept. 29: Feature survey (star or butterfly) pattern with U/W CTD, and micro-structure and
CTD stations
Sept. 30: Feature survey with U/W CTD, and micro-structure and CTD stations
Sept. 30: Feature survey with U/W CTD, and micro-structure and CTD stations
Oct. 1: Feature survey with U/W CTD, and micro-structure and CTD stations
Oct. 2: Feature survey with U/W CTD, and micro-structure and CTD stations
Oct. 3: Feature survey with U/W CTD, and micro-structure and CTD stations
Oct. 4: Feature survey with U/W CTD, and micro-structure and CTD stations
Oct. 5: Check moorings, CTD stations at moorings, retrieve some gliders, begin steam for Azores
Oct. 6: Steam toward 25° N 35.5° W to deploy 7 surface drifters east of SPURS site
Oct. 7: Steam
Oct. 8: Steam
Oct. 9: Arrive Punta Delgada, Azores
Figure 1. Mooring sites with bathymetry: WHOI mooring at 24°34'N, 38°02'W PICO-East at 24°34'N, 37°49'W, PICO-North at 24°45'N, 38°02'W
Figure 2. Seaglider survey plan. 2 gliders would occupy a 140km x 140 km box centered on the WHOI mooring (red/blue), a third would perform a 50 km scale butterfly pattern around the mooring (purple).
Figure 3. Float deployment positions around central mooring. These are within the 140 x 140 km box defined by the Seagliders (plot border).
Figure 4. UnderWay CTD survey volume around moorings with microstructure and CTD/LADCP profiles at moorings.
