If you have any problems related to the accessibility of any content (or if you want to request that a specific publication be accessible), please contact us at firstname.lastname@example.org.
Tree Rings and the Truckee River: Our Past, Our Future, and George Hardman
AuthorHarris, Victoria M
AdvisorCsank, Adam Z
AltmetricsView Usage Statistics
The Truckee River Basin, located on the Nevada-California border, is an area of extreme hydrologic variability. It can be subject to both prolonged multi-decadal droughts and devastating floods; however, due to the brief instrumental record, the full range of this variability and its potential cyclicity is limited. As tree rings have been shown to be well suited as proxies for annual streamflow, this study revisits the first tree-ring reconstruction of Truckee River runoff, Hardman and Reil (1936), from the perspective of both physical and historical geography.In the same way that local water managers are concerned with the current post-2000 drought, George Hardman and Orvis Reil developed their paper to address questions surrounding their contemporary drought. This study is more than just an extension of their work but in fact a replication. Hardman and Reil’s original tree cores from the 1930s were preserved University of Nevada, Reno Special Collections and Archives and thereby integrated into this new research. Using modern though parallel techniques, these cores along with newly sampled material were measured and processed to develop new tree-ring chronologies for three of Hardman and Reil’s study sites. These were then incorporated into a new Truckee River streamflow reconstruction extending from 1491 to 2003. This represents an over 400-year extension of the instrumental record and provides new insights into the basin’s natural variability. In addition to evidence of extended droughts and extreme high streamflow years, this reconstruction shows a marked hydroclimatic shift centered around 1850. Previously, the Truckee River experienced decadal to multi-decadal higher than average streamflow periods; since then, those periods have been decreasing in length until as we experience today merely 2 to 4 consecutive years of high flow. Whether this represents fundamental shift in the area to a new climatic regime remains unclear. However, as global temperatures continue to rise, fewer long-term high streamflow episodes may have lasting impacts on water availability in the basin and raises the question further of whether the post-2000 drought is a new megadrought or a sign of aridification.Additionally, this study examines George Hardman’s relationship with dendrohydrology both before and after his 1936 publication. It explored how Hardman, a water manager, learned the techniques of a dendrochronologist, which unfortunately remains unclear. Using bibliometrics, the legacy of Hardman and Reil (1936) was assessed and shows its influence on the subdiscipline to only be growing.