18 January 2017: – contributed by Jose Xavier
The Antarctic research cruise JR 16003 is the Western Core Box cruise of the 2016-17 voyage of the RRS James Clark Ross to the Antarctic, around South Georgia, with extra stations at the Antarctic Polar Front region.
Since 1981, the British Antarctic Survey (BAS) have undertaken cruises to determine Antarctic krill (Euphausia superba) biomass as part of the ongoing assessment of the status of the marine ecosystem in the region of South Georgia. It comprises an acoustic grid survey of 8 transects each of 80 km in length, together with associated net and oceanographic sampling and the calibration of acoustic instrumentation. In addition to the acoustic survey, which covers a wide area but has limited temporal coverage, there are three moorings (one on the shelf in the Western Core Box, and two in deep water to the southwest and northwest of South Georgia) to provide a temporal, year-round set of observations. The mooring instruments record parameters such as temperature, salinity and current velocities, as well as sediment traps that enable us to monitor the annual flux of carbon to deep waters. These moorings are recovered during the cruise, refurbished and data downloaded, and then redeployed later in the cruise. The shallow Western Core Box mooring has been in position more or less continuously since 2003.