... Globally, warmer than average sea surface temperatures in the subtropical and tropical North Atlantic, a particularly warm North Atlantic, colder-than-average western/central Pacific, and warming in parts of the northeast Pacific all tend to contribute to drought in central and southwestern North America (Woodhouse and Overpeck, 1998;Fye et al., 2004;McCabe et al., 2004;Schubert et al., 2004;Zhang and Mann, 2005;Booth et al., 2005Booth et al., , 2006Cook et al.,2007Cook et al., , 2010Cook et al., , 2011aCook et al., , 2011bSeager et al., 2008;Brönnimann et al., 2009;Kushnir et al., 2010;Shin et al., 2010;Feng et al., 2011;Nigam et al., 2011;Wang and Schubert, 2014;Donat et al., 2015). Longer-term climatic trends such as the Pacific Decadal Oscillation (PDO), Atlantic Multi-decadal Oscillation (AMO), and Arctic Oscillation (AO), all involving changing sea surface temperature and air pressure patterns, also play a role in modulating and amplifying North American drought cycles, including those in the Great Plains (e.g. ...