Ekman spiral and Ekman transport
Espiral de Ekman y transporte de Ekman
- Date
- 1902-1905 · confidence high
- Place
- Uppsala, Sweden
- Credited to
- Vagn Walfrid Ekman
- Field
- Cosmos & Earth
What was discovered
Ekman explained theoretically why the ice observed by Nansen drifted 20-40° to the right of the wind: the Coriolis force and friction make the current turn spiral-wise with depth. The net water transport lies at 90° to the wind.
The work began from a suggestion by Nansen to Vilhelm Bjerknes; Ekman did it in his thesis (Uppsala, 1902) and developed it in 1905. The ideal spiral is rarely seen in the real ocean, but Ekman transport is a basic concept.
What it led to
- the theory of upwelling on coasts such as Peru and Namibia
- ocean circulation models of Sverdrup and Stommel
- wind measurement from satellite using altimeters and scatterometers