All climate models used by the IPCC failed to predict the “pause” in global warming since 1998. Two Georgia Tech researchers, Dr. Marcia Glaze Wyatt and Dr. Judith A. Curry, hypothesize that multi-decadal oscillations in atmospheric and oceanic circulation regimes, such as the Atlantic Multidecadal Oscillation (AMO) and the Pacific Decadal Oscillation (PDO) can amplify or diminish longer term atmospheric warming or cooling.
Their hypothesis is likened to a “stadium-wave signal that propagates like the cheer at sporting events whereby sections of sports fans seated in a stadium stand and sit as a ‘wave’ propagates through the audience. In like manner, the ‘stadium wave’ climate signal propagates across the Northern Hemisphere through a network of ocean, ice, and atmospheric circulation regimes that self-organize into a collective tempo.”
This study analyzed data from the atmosphere, ocean, and sea ice since 1900. “The study provides an explanation for seemingly incongruous climate trends, such as how sea ice can continue to decline during this period of stalled warming, and when the sea ice decline might reverse. After temperatures peaked in the late 1990s, hemispheric surface temperatures began to decrease, while the high latitudes of the North Atlantic Ocean continued to warm and Arctic sea ice extent continued to decline. According to the ‘stadium wave’ hypothesis, these trends mark a transition period whereby the future decades will see the North Atlantic Ocean begin to cool and sea ice in the Eurasian Arctic region begin to rebound.”
The Stadium Wave hypothesis predicts that the current “pause” in warming will continue well into the 2030s.
Near the end of their paper, the researchers provide this caveat: “While evidence strongly supports our hypothesis of a secularly varying climate signal propagating through a hemispheric network of synchronized ocean, atmosphere, and ice indices during the 20th century, we cannot know if this variability, tempo, and sequential chronology will continue into the future. How changes in external forcing might affect the Eurasian Arctic sea ice in context of an apparent quasi-oscillatory ocean-ice-atmosphere system is a burning question.”
They do note that study of 300 year proxy data suggests changes in tempo and amplitude of the “Stadium Wave” did occur prior to the 1800s.
The bottom line is that this hypothesis explains the behavior of global temperature while the carbon dioxide hypothesis does not.
The research is published in the September issue of Climate Dynamics.
Another paper relating the AMO and PDO cycles to conditions in the Southwestern US concludes: “If the AMO continues its quasi-cyclic behavior the US SW temperature should remain stable and the precipitation should significantly increase during the next few decades.” That bodes well for our future water supply. For that story see here.