Climate Change and Variability in the North Atlantic : From Tip Jets to Warming Holes

Abstract: In this talk, I’ll present recent ocean-atmosphere interaction results using both the latest models and state of the art observations with a focus on the mid-high latitude North Atlantic. The models include the new NOC coupled 1/12^o ocean-atmosphere climate run and the observations feature measurements from the novel Ocean Observatories Initiative surface flux reference site mooring in the Irminger Sea. A range of spatial and temporal scales will be considered, from the properties of Greenland tip jets (50-500km, hours-days, heat loss up to 800 Wm^-2) to anthropogenic climate change (global, centuries long, but just 0.5 Wm^-2). In between, lies the Big Blue Blob, a large region of persistently low surface temperatures, accompanied by a sharp reduction in ocean heat content, that was evident in the subpolar gyre from winter 2013-14 to 2016. The presence of this feature stimulated considerable debate and I’ll discuss the role of air-sea interaction and ocean processes in its generation. Finally, the possibility that this event and a simultaneous warm anomaly in the North Pacific represent a response to the melting Arctic will be explored.