Validation of a three-dimensional biophysical model using nutrient observations in the North Sea

Abstract

A three-dimensional, coupled, physical-chemical-biological model (NORWECOM) is validated by means of observed nutrient fields in the North Sea. The observations used in this study are aggregated nutrient data for the period 1980-1989 obtained from ICES. The data have been grouped in winter, early summer and late summer sets and mean values with standard deviations are given for 0.5°latitude x 1.0°longitude boxes covering the North Sea. The nutrient fields from the NORWECOM model are used to produce an aggregated model data set that is compared with the observed values. Results of both the model's ability to reproduce the mean observed nutrient concentrations and the spatial variability are presented. Since the differences are typically larger in areas with high variability, a costfunction approach, i.e. the differences between observations and model data weighted with the standard deviation, is used in the comparison. (C) 2000 International Council for the Exploration of the Sea.