Climate-driven synchrony across tree, bivalve, and rockfish growth-increment chronologies of the northeast Pacific

Abstract

Interrelationships are analyzed among growth-increment chronologies of yelloweye rockfish Sebastes ruberrímus, splitnose rockfish Sebastes diploproa, and the bivalve species Pacific geoduck Panopea abrupta in the northeast Pacific. The chronologies are annually resolved, multidecadal in length, and range in location from central California through northern British Columbia. In a principal components analysis, the first component explained 52 % of the variance in the dataset and separated chronologies from the northern half of the study area from those in the southern half. The northern chronologies significantly and positively correlate with seasonally averaged records of the Multivariate ENSO Index (MEI) and the Pacific Decadal Oscillation (PDO), while the southern chronologies negatively correlate with the same variables, especially during the winter and spring. Such an inverse growth regime is consistent with primary and secondary productivity patterns in the northeast Pacific. The second principal component accounted for 23 % of the variance in the dataset and captured a growth pattern associated with climatic variability in the spring and summer months. Both principal components derived from the marine chronologies relate to tree-ring chronologies in western North America, due to shared sensitivities to climatic variability. Interrelationships among these chronologies underscore the synchronous and pervasive impacts of climate on very diverse taxa and ecosystems in western North America. © Inter-Research 2009.