Nutrient distributions in the winter regime of the northern Irish Sea

Quasi-synoptic distributions of salinity and the concentrations of dissolved inorganic nutrients in the winter regime of the northern Irish Sea are presented. Salinity to nutrient regression analyses and the distributions of nutrient ratios show that the characteristics of Atlantic waters are variously modified during their northward passage through the Irish Sea. Inherently different chemical characteristics of the fresh water sources discharging into the Northern Irish Sea generate a conglomeration of water types in the area. Marine waters along the Irish coast are relatively enriched in silicon, while waters adjacent to the eastern coastal boundary are relatively enriched by anthropogenic nitrogen sources. Possible implications of the spatial dichotomy in nutrient status for the seasonal production cycle in the northern Irish Sea are considered.