RRS James Clark Ross Cruise JR306, 10-20 Jan 2015. Hydrographic measurements on WOCE line SR1b

Twentieth complete occupation of the Drake Passage section, established during the World Ocean Circulation Experiment as repeat section SR1b, first occupied in 1993 and re occupied most years since then. Full-depth temperature, salinity, and lowered ADCP velocity profiles were measured at the 30 repeat stations (with the 9 northern stations along 58 W, as from 2009 on). Underway measurements included navigation, VM-ADCP, sea surface temperature and salinity, water depth, and meteorological variables. The objectives were to investigate interannual variability in Antarctic Circumpolar Current (ACC) structure and Transport, the positions of the ACC fronts, and Drake Passage temperature and salinity distributions.