Oceanologia (Feb 2013)
Modelling flow in the porous bottom of the Barents Sea shelf
Abstract
In their recent paper, Węsławski et al. (2012) showed that theSvalbardbanken area of the Barents Sea is characterized by a high organiccarbon settlement to the permeable sea bed, which consists of gravel andshell fragments of glacial origin.In the present paper, which can be considered as a supplement to the Węsławskiet al. paper, two potential hydrodynamic mechanisms of downwardpore water transport into porous media are discussed in detail.In particular, estimated statistical characteristics of the pore waterflow, induced by storm surface waves, indicate that the dischargeof water flow can be substantial, even at large water depths.During stormy weather (wind velocity V=15 m s-1 and windfetch X =200 km) as much as 117.2 and 26.1 m3 hour-1 ofwater filter through the upper 5 m of the shell pit at waterdepths of 30 and 50 m respectively. For a porous layer ofgreater thickness, the mean flow discharge is even bigger. The second possible mechanism of flow penetration in the porous layeris based on the concept of geostrophic flow and spiral formation withinthe Ekman layer. Assuming that the current velocity in the near-bottomwater layer is ū = 1 m, the resulting mean dischargethrough this layer becomes as large as 0.99 and 0.09 m3 s-1for downstream and transverse flows respectively.
