Using the frequent crossings of the Drake Passage by the RV/AS Gould as USAP supply ship to Palmer Station, UCSD researchers will continue the collection of upper ocean XBTs (expendable Bathythermograph for depth, temperature) and XTCD (expendable temperature, conductivity and depth profiler) salinity data in this natural chokepoint for the Antarctic Circumpolar Current (ACC). This will continue to yield hydrographic observations on seasonal to interannual timescales, and on spatial scales ranging from the current core to mesoscale eddies. These high-resolution, multi-repeat transects and depth profiles (up to 12-16 crossings per year) are quality controlled, archived and made available to the broader community in order to facilitate study of the modes of variability of the ACC, the dominant surface ocean current on the planet.
The Drake Passage XBT/XCTD transect time series now extends back to 1996, and continues to add to a number of key quantitative estimates of the long term trends in Southern Ocean fronts, surface water mass properties, their response to atmospheric forcing on climate relevant time scales, and their roles in driving the meridional overturning circulation of the Southern Ocean.
