Thermohaline circulation of shallow tidal seas
|Title||Thermohaline circulation of shallow tidal seas|
|Publication Type||Journal Article|
|Year of Publication||2008|
|Authors||Hill, AE, Brown, J, Fernand, L, Holt, J, Horsburgh, KJ, Proctor, R, Raine, R, Turrell, WR|
|Journal||Geophysical Research Letters|
|Keywords||circulation, fronts, thermohaline|
The mechanisms controlling the temperature and salinity structure of shallow continental shelf seas have been understood for over thirty years, yet knowledge of what drives their large-scale circulation has remained relatively unknown. Here we describe a decade long programme of measurements, using satellite-tracked drifting buoys on the northwest European shelf, to draw attention to a striking picture of highly organised thermohaline circulation consisting of narrow, near surface, fast flowing jets. These are ubiquitous above sharp horizontal gradients in bottom temperatures and/or salinities. The circulation phenomena we describe are likely to be prevalent on all similar, wide, tidally energetic continental shelves including those off north-eastern China, Argentina and parts of the Arctic. The robust, repeatable observation of the key role of jets above bottom fronts results in a fundamental reassessment of how we view the dynamics of shelf seas.