Work Package 1 Atlantic and Irish Shelf variability 

The future climate of the North Atlantic may differ from that of every other ocean. While the surface of most oceans is predicted to warm at a similar rate to the global average, a relative cooling may occur in the Atlantic. Much of this deviation from the global mean is due to a predicted slowdown in the Atlantic Meridional Overturning Circulation (AMOC) linked to anthropogenically driven climate change. The AMOC is a system of currents that moves warm water northwards in the Gulf Stream and North Atlantic Current and returns it as cold, deep southward flow.

In recent years, the Atlantic has recorded its record coldest and record freshest values. By making new measurements and analysing observations and models, we investigate whether this behaviour is a canary in the coalmine for major AMOC change. Episodic AMOC collapse has been associated with large shifts in climate of up to 10ºC during the last glacial period. Instrumental data link the AMOC with multi-decadal phases of anomalous Atlantic sea surface temperatures that have widespread climate impacts, including climate variations in northwestern Europe.

Understanding the state of the Atlantic Ocean, its evolution and impacts on climate is a pre-eminent problem for societies in the 21st Century.