A recent study presents evidence that regional warming over the Arctic Ocean can affect mid-latitude Northern Hemisphere continental weather. This study shows that there are two key Arctic regions where regional warming can induce distinguishable cold winters over northern continents. Warming over the Barents–Kara Sea region is likely to lead to East Asian cooling, whereas northern North America cooling is closely related to warming over the East Siberian–Chukchi Sea region.
For most of the past 18,000 years warm temperatures in the North Pacific often correspond to cold temperatures in the North Atlantic and vice versa. In this study it is revealed that the occasional synchronicity in the North Pacific and North Atlantic climates correspond to periods of abrupt Northern Hemisphere warming.
Evidence from Antarctic ice cores have revealed a close correlation between surface temperature and atmospheric carbon dioxide concentration for the past 800,000 years (excluding the immediate present.) A recent analysis of Antarctic blue ice has found that the close correlation between temperature CO2 extends to 1.5 million years ago during the time when the glacial/interglacial period was 40,000 years.
Marine cores collected in the western tropical Pacific were used to compare the chronology of Southern Ocean warming near Antarctica and rising CO2 during the last deglaciation. The results provide evidence that the Southern Ocean off Antarctica warmed by ~2°C between 19,000 and 17,000 years before the present, about 1,000 years before the rise in atmospheric CO2.