Antarctic Circumpolar Current: transport and properties

Oceans 2025 Theme 10, Bottom Pressure Recorders for Drake Passage ACC

The Drake Passage has been identified by CLIVAR and GLOSS as a strategic choke point for the global ocean circulation. Long term monitoring of bottom pressure, temperature and sea level at this position have been shown to reflect circum-Antarctic flow (Hughes et al 1999; 2003; Meredith et al 2004). As a by-product of the pressure measurements, temperature time-series have identified processes which may have an important impact on the global ocean circulation, such as annual deep water formation events (Meredith et al 2003). In order to obtain sufficiently accurate values for annual mean transport measurement it is necessary to make measurements more frequently than every 10 days (Meredith & Hughes, 2005). Much of the bottom pressure information can also be extracted from tide gauge records on the Antarctic Peninsula (see SO 7 - UK GLOSS), which also have the advantage of accurate datum control between years. POL will maintain the key measurements to the north and south of Drake Passage, while adding deployments at different depths in order to assess the need for a continuation of the observations. This period coincides with the International Polar Year, during which a number of other observation campaigns will take place. Together, these will provide much greater contextual information to assist in interpreting the historical data and planning the appropriate scale of future activities

Team

Peter Foden
Geoff Hargreaves
Chris Hughes
Steve Mack
Miguel Angel Morales Maqueda