Oceanic Influence on Chiricahua Mountains Drought Observed in a 383-Year Douglas-Fir Reconstruction

Drought in the North American Southwest is a recurring phenomenon. The knowledge of drought recurrence and severity is crucial for sustainable water resource management in the region. Tree-ring reconstructions of climate variables provide valuable indirect evidence of climate variability and elucidate the relationship between large-scale circulation anomalies and the climate in the region. Here we have developed a May-July Palmer Drought Severity Index (PDSI) reconstruction from tree-ring chronologies of Pseudotsuga menziesii from the Chiricahua Mountains (southeastern Arizona) for the period 1634-2017 CE. The driest period occurred at the beginning of the 21st Century (2000-2005), followed by 1666-1670, 1952-1956, and 1729-1734. Reconstructed PDSI of the Chiricahua Mountains shows a weak correlation with the El Niño-Southern Oscillation, with intermittent influence as previous studies have reported. The Pacific Decadal Oscillation accounts for the majority of the variability in the Chiricahua hydroclimate, except for the period from 1860-1950 when the predominant driver was the North Atlantic Oscillation.