Tree-ring Isotopes Adjacent to Lake Superior Reveal Cold Winter Anomalies for the Great Lakes Region of North America

Authors

Steven L. Voelker, Utah State University
Simon S.-Y Wang, Utah State University
Todd E. Dawson, University of California-Berkeley
John S. Roden, Southern Oregon University
Christopher J. Still, Oregon State University
Fred J. Longstaffe, The University of Western OntarioFollow
Avner Ayalon, Geological Survey of Israel

Document Type

Article

Publication Date

3-13-2019

Volume

9

Issue

4412

Journal

Scientific Reports

First Page

1

URL with Digital Object Identifier

https://doi.org/10.1038/s41598-019-40907-w

Last Page

10

Abstract

Tree-ring carbon isotope discrimination (Δ¹³C) and oxygen isotopes (δ¹⁸O) collected from white pine (Pinus strobus) trees adjacent to Lake Superior show potential to produce the first winter-specific paleoclimate reconstruction with inter-annual resolution for this region. Isotopic signatures from 1976 to 2015 were strongly linked to antecedent winter minimum temperatures (T_min), Lake Superior peak ice cover, and regional to continental-scale atmospheric winter pressure variability including the North American Dipole. The immense thermal inertia of Lake Superior underlies the unique connection between winter conditions and tree-ring Δ¹³C and δ¹⁸O signals from the following growing season in trees located near the lake. By combining these signals, we demonstrate feasibility to reconstruct variability in T_min, ice cover, and continental-scale atmospheric circulation patterns (r ≥ 0.65, P < 0.001).