April 2017

Tree-ring Talk by Candidate for Ltrr Faculty Position

Trees rings record a wealth of information on climate, disturbance, and forest dynamics, and can record these processes from the plot to regional to global scales. However, extracting plant physiological processes from the tree ring record has proved to be more difficult, as integration of leaf to whole tree processes can often lead to confounding results. My research aims to bring a plant ecophysiological perspective to interpreting the tree ring record and to ask, what processes are the rings actually recording?

Along North America's West Coast, winter sea level pressure is a top-down driver of coastal upwelling, precipitation, and river discharge. Remarkable coherence among these geophysical parameters induces covariance of biological productivity across marine and terrestrial ecosystems, as evidenced by growth-increment chronologies of fish, clams, and trees. Robust paleoenvironmental records indicate that these biologically-relevant winter climate patterns are dominated by low-frequency, 40-60 year periodicities at higher latitudes.