Experiments in Objectively Predicting Some Atmospheric and Oceanic Variables for the Winter of 1971–72

Abstract

The oceanic and atmospheric anomalies of the winter of 1971?72, markedly different from those Prevailing during the 1960's, are described, analyzed, and subjected to experimental objective predictions. Sea-surface temperature patterns over the North Pacific developed in such a slow, orderly fashion from fall 1971 to the following winter that a kinematic treatment successfully captured the evolution. Physical processes associated with this evolution are investigated and show that local air-sea heat exchange played a negligible role relative to winter-mass transport around the North Pacific oceanic gyre. The resulting winter sea-surface temperature pattern appeared to place demands on the overlying circulation, producing anomalous atmospheric flow patterns at sea level and aloft. A multiple-regression analysis based on 20 independent winters? data was successfully used to predict the probable winter 1971?72 sea-level pressure pattern from the observed fall 1971 sea-surface temperature pattern. Finally the winter 1971?72 regime is considered as a break with the prevailing state of the winters since 1958, posing the unanswered question of whether a new climatic regime is emerging for the 1970's.