Document Type
Article
Journal/Book Title/Conference
Atmosphere
Volume
10
Issue
12
Publisher
M D P I AG
Publication Date
12-7-2019
Award Number
NSF, Division of Atmospheric and Geospace Sciences (AGS) 1903721
Funder
NSF, Division of Atmospheric and Geospace Sciences (AGS)
First Page
1
Last Page
15
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
Abstract
In recent years, a pair of large-scale circulation patterns consisting of an anomalous ridge over northwestern North America and trough over northeastern North America was found to accompany extreme winter weather events such as the 2013–2015 California drought and eastern U.S. cold outbreaks. Referred to as the North American winter dipole (NAWD), previous studies have found both a marked natural variability and a warming-induced amplification trend in the NAWD. In this study, we utilized multiple global reanalysis datasets and existing climate model simulations to examine the variability of the winter planetary wave patterns over North America and to better understand how it is likely to change in the future. We compared between pre- and post-1980 periods to identify changes to the circulation variations based on empirical analysis. It was found that the leading pattern of the winter planetary waves has changed, from the Pacific–North America (PNA) mode to a spatially shifted mode such as NAWD. Further, the potential influence of global warming on NAWD was examined using multiple climate model simulations.
Recommended Citation
Chien, Y.-T.; Wang, S.-Y.S.; Chikamoto, Y.; Voelker, S.L.; Meyer, J.D.D.; Yoon, J.-H. North American Winter Dipole: Observed and Simulated Changes in Circulations. Atmosphere 2019, 10, 793.
