Journal article

A 500-Year Tree Ring-Based Reconstruction of Extreme Cold-Season Precipitation and Number of Atmospheric River Landfalls Across the Southwestern United States

Scott Steinschneider, Michelle Ho, A Park Williams, Edward R Cook, Upmanu Lall



This study develops a reconstruction of the frequency of extreme cold-season precipitation and the occurrence of landfalling atmospheric river (AR) storm tracks across the southwestern Unites States using a network of tree ring chronologies and the Living Blended Drought Atlas (LBDA), a 500-year tree ring based reconstruction of the summer Palmer Drought Severity Index. The first two rotated empirical orthogonal functions of the LBDA across the Southwest are shown to relate well to previously identified patterns of regional AR activity. Accordingly, the rotated empirical orthogonal functions also record patterns of extreme precipitation associated with those ARs, albeit with some uncertainty..

View full abstract

University of Melbourne Researchers


Awarded by NSF

Funding Acknowledgements

Much of the data used in this analysis are publicly available through NOAA online repositories, including the gridded precipitation, NCEP reanalysis, and LBDA. We thank Dave Stahle, Dorian Burnette, Daniel Griffin, and Max Torbenson for providing the cold-season precipitation-sensitive tree ring chronologies used here, which are available from the International Tree-Ring Data Bank at NOAA ( We also thank Swen Brands for providing the database of landfalling atmospheric rivers, which is available at The authors acknowledge support from NOAA and from NSF grants AGS1702273, AGS1702184, AGS1703029, and AGS1301587. Lamont-Doherty Earth Observatory contribution 8223.