Decadal changes in ecological provinces of the Northwest Atlantic Ocean revealed by satellite observations

Abstract

Detecting the effect of climate change on ocean ecosystems is facilitated if the data are partitioned into ecological provinces. It is recognised that the boundaries of such provinces are dynamic, raising the imperative for frequent observations. Using satellite data, we have assembled a time series of ecosystem delineation for the Northwest Atlantic Ocean over a period of ten years. For each province identified in the study area, we have compiled data on sea-surface temperature, and on the biomass and community composition of phytoplankton. We find significant trends in these properties but they vary according to the province concerned, which emphasizes how the physical and biological changes are correlated at large scale. Comparisons between the trends computed using the average position of the provinces and the trends derived when accounting for the movements of the boundaries underline the value of the new approach. Copyright 2009 by the American Geophysical Union.