The flow through the north channel of the Irish Sea

Using Acoustic Doppler Current Profilers (ADCP) and Ocean Surface Current R adar (OSCR HF Radar) a 15-month data set for the current profile and surfac e currents across the North Channel of the Irish Sea has been collected. Du ring the period July 1993-August 1994 the volume flux through the North Cha nnel between Portpatrick and Banger was estimated to be (0.077 +/- 0.013) x 10(6) m(3) s(-1) towards the Malin Shelf, concentrated near to the Scottis h coast. A simple residual current and wind stress correlation model sugges ts that large wind stresses were important for residual flow. The current p rofile in the middle of the channel showed a complex pattern with mean infl ow at the surface and mean outflow at the near-bed. Mean along-channel wind stresses for February 1994 and particularly for a large storm during 3-4 F ebruary 1994 were atypical of the last decade, with large mean wind stresse s directed towards the Malin Shelf. These resulted in: the largest monthly mean flow towards the Malin Shelf, equivalent to 34% of the volume of the I rish Sea passing through the North Channel; the two largest daily mean flow s towards the Malin Shelf, equivalent to an along-channel transport of 97 k m. Pressure gradients were calculated from elevation measurements and an at tempt to calculate the across channel momentum balance was partially succes sful using Coriolis, Pressure Gradient, Surface Stress, Local Acceleration and Bottom Stress terms. (C) 1999 Elsevier Science Ltd. All rights reserved .