The Liverpool Bay Coastal Observatory — Analysis of Seasonal Cycles

The pilot Coastal Observatory in the eastern Irish Sea (http://coastobs.pol.ac.uk) integrates (near) real-time measurements with coupled models in a pre-operational coastal prediction system. Started in 2002 the initial setup was reported in Proctor et al. The aim is to develop the underpinning science for marine management, focusing on the impacts of storms, eutrophication and the relative importance of events viz-a-viz the mean. Measurements include: in situ vertical profiles of current, temperature, salinity, turbidity, nutrients and chlorophyll; shore-based HF radar measuring waves and surface currents out to 50 km; the Birkenhead-Belfast ferry measuring surface properties; waves; tide gauges; satellite data including infrared (for sea surface temperature) and visible (for chlorophyll and suspended sediment). In cooperation with the National Centre for Ocean Forecasting (NCOF), a suite of nested three-dimensional models (the Proudman Oceanographic Laboratory Coastal Ocean Modelling System - POLCOMS) is run daily, focusing on the Observatory area by covering the ocean/shelf of northwest Europe (at 12 km resolution), the NW European continental shelf (at 7km), the Irish Sea (at 1.8 km) and (soon) Liverpool Bay (at 200–300m resolution). Recently near-real time river discharges have become available for input to the higher resolution models. Nutrient and plankton dynamics are simulated with the ERSEM (European Regional Seas Ecosystem Model) component of POLCOMS. A critical analysis of the approach can now be made based on more than 2 years' operation. In particular the seasonal cycles of physics, nutrients and biology, and their interaction with the tides and coastal discharges is becoming apparent.