Amplified Arctic warming and mid-latitude weather: new perspectives on emerging connections

The Arctic is warming and melting at alarming rates. Within the lifetime of a Millennial, the volume of ice floating on the Arctic Ocean has declined by at least half. The pace of Arctic warming is two-to-three times that of the globe; this disparity reached a new record high during 2016. While the Arctic spans only a small fraction of the Earth, it plays a disproportionate and multifaceted role in the climate system. In this article, we offer new perspectives on ways in which the Arctic's rapid warming may influence weather patterns in heavily populated regions (the mid-latitudes) of the Northern Hemisphere. Research on this topic has evolved almost as rapidly as the snow and ice have diminished, and while much has been learned, many questions remain. The atmosphere is complex, highly variable, and undergoing a multitude of simultaneous changes, many of which have become apparent only recently. These realities present challenges to robust signal detection and to clear attribution of cause-and-effect. In addition to updating the state of this science, we propose an explanation for the varying and intermittent response of mid-latitude circulation to the rapidly warming Arctic. (c) 2017 Wiley Periodicals, Inc.