Water exchange in a Faroese fjord system

The largest fjord system in the Faroe Islands consist of a 35 km long and up to 4 km wide strait with three 4-13 km long adjacent fjords. The system includes several basins, some of which are separated by narrow sills. Generally the circulation in the system is estuarine and/or wind driven, and occasionally an isolated bottom layer appears in the deepest basins. The southern end of the area is located at an amphidromic point, which implies quite limited tidal influence in the southern part of the strait and adjacent fjords. The northern part, however, has a maximum tidal range of 2,4 m. This causes strong mixing across the shallow sill separating these areas. Over the years current profile time series are obtained at 13 locations in the system, and recently temperature, salinity and oxygen profiles are collected to describe the hydrography in the area, including its variability and seasonal changes. Particular emphasis is on describing the water exchange between the basins and the processes controlling the mixing of the water masses and renewal of the bottom layers. Of interest are also potential effects of having redirected a major fraction of the freshwater runoff from the southern part of the strait to the northern basin due to a hydro power plant construction.