Drought variations in the study area significantly correlated with sea surface temperatures (SSTs) in North Pacific Ocean, suggesting a possible connection of regional
hydroclimatic variations to the Pacific
Decadal Oscillation (PDO).
Our results show that
hydroclimatic variability in the Southwest has not remained constant over the last millennia, with a shift from low to high variance at the MCA - LIA transition that was accompanied by a change in quasi-periodic variance, from a higher concentration of power in the multi-
decadal periodicities during the MCA vs. interannual and
decadal periodicities during the LIA.