The Bermuda Atlantic Time-series Study (BATS) is a long-term oceanographic study by the Bermuda Institute of Ocean Sciences (BIOS). Based on regular (monthly or better) research cruises, it samples an area of the western Atlantic Ocean nominally at the coordinates 31°40′N 64°10′W / 31.667°N 64.167°W. The cruise programme routinely samples physical[1] properties such as ocean temperature and salinity, but focuses on variables of biological or biogeochemical[2] interest including: nutrients (nitrate, nitrite, phosphate and silicic acid), dissolved inorganic carbon, oxygen, HPLC of pigments, primary production and sediment trap flux. The BATS cruises began in 1988 but are supplemented by biweekly Hydrostation "S" cruises to a neighbouring location (32°10′N 64°30′W / 32.167°N 64.500°W) that began in 1954.[3] The data collected by these cruises are available online.