SEARCH Projects

Ecosystem Change in the Northern Bering Sea

Jackie Grebmeier James Overland Terry Whitledge Institution: University of Tennessee, Knoxville

Abstract

This project investigates the hypothesis that recent anomalous spring and summer productivity on the Northern Bering Sea shelf relates to decadal-scale atmospheric/sea ice/oceanographic processes, which reflect regime-induced climate changes in the western Arctic. Recent work (Grebmeier and Dunton 2002; Cooper et al. 2002) shows that there are hot spots of biological productivity southwest of Saint Lawrence Island, and that this productivity has been decreasing over the past decade. Stabeno and Overland (2001) report the Bering Sea is shifting to an earlier spring transition based on ice melt and changes in atmospheric circulation patterns. Since changes in the North Pacific Oceans show little long-term trend while the trend in Arctic Oscillation appears to be a clearly increasing climate signal, the northern Bering Sea is an important location to monitor ecosystem change. The combination of these studies demonstrate the timeliness for increased focus on the ecosystem of the northern Bering Sea. To establish such a program we propose the following tasks:

1) A retrospective analysis of all northern Bering Sea data to put future changes into context and to provide an objective measure for change detection.

2) Establishment of a northwest Bering Sea biophysical oceanographic mooring to document ongoing changes, similar to the successful multiyear FOCI mooring, M2, on the southeast Bering Sea shelf.

3) Process studies of the northern biological hot spots, primarily funded by non-NOAA sources.