In oceanography, the sverdrup (symbol: Sv) is a non-SI metric unit of flow, with 1 Sv equal to 1 million cubic metres per second (260,000,000 US gal/s);[1][2] it is equivalent to the SI derived unit cubic hectometer per second (symbol: hm3/s or hm3⋅s−1). It is used almost exclusively in oceanography to measure the volumetric rate of transport of ocean currents. It is named after Harald Sverdrup.