PAIRED SPELEOTHEM AND LACUSTRINE PALEOCLIMATE RECORDS FROM THE BEAR RIVER RANGE, SOUTHEAST IDAHO

A paired speleothem isotope record from Minnetonka Cave and a lacustrine pollen and charcoal record from Plan B Pond are presented from the Bear River Range, Southeast Idaho. These records show significant hydroclimatic variability and ecological response through the Holocene and provide data points from a dominant hydroclimatic transition zone that divides western North America into oppositely responding north and south regions. Spatiotemporal variations in hydroclimates across the American West have been correlated with large-scale Pacific climate indices such as ENSO and PDO. The relatively consistent opposing north-south response in winter precipitation to ENSO and PDO phases provides predictive insight to understanding the water resource availability in a region dependent on snowpack to support its water needs. However, within the transition zone between these well-defined northern and southern hydroclimatic response regions, predictive capabilities are much diminished due to a weaker correlation with the large-scale climate indices. Paleoclimate timeseries from this transition zones serve to inform about the transition zone location and relative climate sensitivity over time.