Cruise inventory
RRS James Clark Ross JR20120120 (JR255A)
Cruise summary report
| Cruise Info. | |
| Ship name (ship code) | RRS James Clark Ross (74JC) |
| Cruise identifier | JR20120120 (JR255A) |
| Cruise period | 2012-01-20 — 2012-02-03 |
| Status | Completed |
| Port of departure | Stanley, Falkland Islands (Malvinas) |
| Port of return | Stanley, Falkland Islands (Malvinas) |
| Purpose | Research |
| Objectives | The objectives of the GENTOO project are:
(i) to quantify and understand the possible new source of dense water overflow and its variability; to determine the outflow’s potential as an early indicator of Antarctic climate change; to assess the impact of changing dense overflows on the locations and strengths of the surface currents and frontal jets; to provide valuable constraints for climate models that describe how changes in ocean circulation feedback on and regulate climate change in polar latitudes. (ii) to determine the krill biomass distribution and (temporal and spatial) variability to the east of the Antarctic Peninsula and its likely impact on the circumpolar krill ecosystem; to assess the impact of any variations in the location of the frontal jets (from objective i) on the krill biomass distribution; to alleviate a severe regional lack of field data on krill, a key species in the Antarctic food web. To achieve the two objectives, our technological deliverable is a critical evaluation of our ability to measure (i) current velocity from a glider and (ii) krill biomass from a glider. The GENTOO fieldwork in the Weddell Sea was accomplished through a SeaGlider campaign in early 2012. A glider deployment cruise (JR255A) was the primary data gathering exercise; as well as deploying three SeaGliders, a hydrographic survey was undertaken together with nets and underway biological, chemical and physical measurements. The recovery of the three gliders was to have taken place on the recovery cruise. |
| Chief scientist | Karen J Heywood (University of East Anglia School of Environmental Sciences) |
| Project | Gliders: Excellent New Tools for Observing the Ocean (GENTOO) |
| Coordinating body | Natural Environment Research Council (NERC) |
| Cruise report |  (2.71 MB) |
| Ocean/sea areas | |
| General | Southern Ocean |
| Specific | Drake Passage, Weddell Sea, Powell Basin |
| Track charts | (0.03 MB) |
| Measurements | |
| Physical oceanography | |
| Surface measurements underway (T,S) | Quantity: activity duration in days = 12 Description: Underway Temperature and Salinity of surface water |
| Bathythermograph | Quantity: activity duration in days = 12 Description: Underway Temperature and Salinity of surface water |
| CTD stations | Quantity: number of stations = 41 Description: Vertical profiles of Salinity, Temperature, Dissolved Oxygen, Chlorophyll |
| Current profiler (eg ADCP) | Quantity: activity duration in days = 12 Description: ADCP current velocities |
| Chemical oceanography | |
| Isotopes | Quantity: number of stations = 9 Description: Nitrous oxide isotopes |
| Biology and fisheries | |
| Primary productivity | Quantity: number of stations = 37 Description: Chlorophyll and phytoplankton data |
| Crustaceans | Quantity: number of hauls = 5 Description: Krill sample catch |
| Acoustic reflection on marine organisms. | Quantity: activity duration in days = 12 Description: EK60 backscatter data |
| Moorings, landers, buoys | |
| Physical oceanography | |
| Subsurface temperature and salinity measurements | 63° 22' 17" S 52° 58' 35" W — Seaglider 522 deployment, measuring Chlorophyll fluroescence, Oxygen, Temperature, Salinity |
| Subsurface temperature and salinity measurements | 63° 22' 35" S 52° 58' 30" W — Seaglider 539 depoyment measuring dissolved oxygen, Temperature, Salinity, chlorophyll fluorescence |
| Subsurface temperature and salinity measurements | 61° 36' 29" S 48° 25' 35" W — Seaglider 546, measuring Temperature, Salinity |
| Neutrally buoyant floats | 63° 31' 17" S 51° 7' 11" W — Argo float measuring Temperature and Salinity |
| Neutrally buoyant floats | 63° 31' 17" S 51° 7' 11" W — Argo float measuring Temperature and Salinity |
| Neutrally buoyant floats | 63° 1' 29" S 51° 30' 0" W — Argo float measuring Temperature and Salinity |
