Potential Feedbacks Between Pacific Ocean Ecosystems and Interdecadal Climate Variations

Abstract

Oceanic ecosystems altered by interdecadal climate variability may provide a feedback to the physical climate by phytoplankton affecting heat fluxes into the upper ocean and dimethylsulfide fluxes into the atmosphere. O ceanic ecosystems influence climate on many time and space scales. But this influence is not well understood. It is clear that interdecadal 1 physical climate variations occur in the Pacific sector. Interdecadal sea surface temperature (SST) anoma-1 We use the term "interdecadal" to loosely refer to timescales that are longer than interannual (ENSO) and shorter than centennial (greenhouse gas forcing). lies show a "canonical" structure (e.g., Tanimoto et al. 1993; Zhang et al. 1997), with central North Pacific SSTs near the subtropical front bracketed to the east, north, and south by oppositely signed SSTs. A second SST pattern is centered around the subpolar front in the Kuroshio-Oyashio Extension region (Deser and Blackmon 1995; Nakamura et al.