ARS | Publication request: Pacific/North American teleconnection controls on precipitation isotope ratios across the contiguous United States

Submitted to: Elsevier
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: August 25, 2011
Publication Date: September 29, 2011
Citation: Liu, Z., Kennedy, C.D., Bowen, G.J. 2011. Pacific/North American teleconnection controls on precipitation isotope ratios across the contiguous United States. Earth and Planetary Science Letters. 310:319-326.

Interpretive Summary: Large-scale climate teleconnections such as the Pacific/North American (PNA) pattern strongly influence atmospheric processes and continental climate. Here we show that precipitation delta18O values in the contiguous United States are correlated with an index of the PNA pattern. The delta18O/PNA relationship varies across the study region and exhibits two prominent modes, with positive correlation in the western USA and negative correlation in the east. This spatial pattern appears not to reflect variation in local climate variables, but rather primarily reflects differences in atmospheric circulation and moisture sources associated with PNA. Our results suggest that strong antiphase variation in paired paleo-water delta18O proxy records from regions characterized by the two modes of delta18O/PNA correlation, especially in the Midwest and southwestern USA, may provide a robust basis for reconstruction of past variation in the PNA pattern. Understanding the mechanisms of these past climate variations (e.g., PNA pattern) will advance understanding and predictive capability of future climate change and its controlling factors.

Technical Abstract: Large-scale climate teleconnections such as the Pacific/North American (PNA) pattern stronglyinfluence atmospheric processes and continental climate. Here we show that precipitation deltaO-18 values in the contiguous United States are correlated with an index of the PNA pattern. The deltaO-18/PNA relationship varies across the study region and exhibits two prominent modes, with positive correlation in the western USA and negative correlation in the east. This spatial pattern appears not to reflect variation in local climate variables, but rather primarily reflects differences in atmospheric circulation associated with PNA. Our results suggest that strong antiphase variationin paired paleo-water deltaO-18 proxy records from regions characterized by the two modes of deltaO-18/PNA correlation, especially in the Midwest and southwestern USA, may provide a robust basis for reconstruction of past variation in the PNA pattern.