Sverdrup

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. It is distinct from the SI unit sievert or the non-SI svedberg, which are unrelated to the sverdrup but use the same symbol.

In the context of ocean currents, a volume of one million cubic meters may be imagined as a "slice" of ocean with dimensions 1 km × 1 km × 1 m (width × length × thickness). At this scale, these units can be more easily compared in terms of width of the current (several km), depth (hundreds of meters), and current speed (as meters per second). Thus, a hypothetical current 50 km wide, 500 m (0.5 km) deep, and moving at 2 m/s would be transporting 50 Sv of water.

Examples[]

The water transport in the Gulf Stream gradually increases from 30 Sv in the Florida Current to a maximum of 150 Sv south of Newfoundland at 55° W longitude.^[3]

The Antarctic Circumpolar Current, at approximately 125 Sv, is the largest ocean current.^[4]

The entire global input of fresh water from rivers to the ocean is approximately 1.2 Sv.^[5]

References[]