A coherency between the North Atlantic temperature nonlinear trend, the eastern Arctic ice extent drift and change in the atmospheric circulation regimes over the northern Eurasia

Atlantic Multidecadal Oscillation (AMO) monthly time series were investigated for last 150 years by implementation of a comprehensive smoothing technique controlled by cross-validation procedure, which provided more statistically significant trend evaluation than moving average or linear trend techniques. It was found that there is a winter sea surface temperature (SST) oscillation of around the 64–69 year scale behind a known SST fluctuation of decadal scale for winter months. The AMO trend demonstrates waters warming in the first part of 20th century, cooling period in 50th and 60th, and warming in 80th–90th years. This result confirms the global ocean conveyer theory of Broker. Weak AMO linear trend respond to the greenhouse warming effect related to carbon dioxide concentration increasing. It demonstrates a slow warming behind a more strong (in amplitude) oscillation responded to still not well understood world ocean properties. This result was confirmed by independent research based on wavelet analysis of the same time series. The ice extent (IE) smoothed curve in Barents and Kara Seas shows a coherent behavior: two minimums (in 20th–30th and in 80th–90th) and one maximum in the middle of 20th century. Coherency of the AMO/NAO/IE trends, on one hand, and SLP/SAT trends, on other hand, proved a close relationship existed in various modules of the climate system (atmosphere‐ocean‐glacial cover) in the Northern Hemisphere.