Jeff Polton¹, James Harle², Jason T Holt³, Anna Katavouta³, Dale Partridge⁴, Enda O'Dea⁵, Pierre Mathiot⁶, Diego Bruciaferri⁷, Alex Arnold⁸ and Katherine Hutchinson⁹, (1)National Oceanography Center, Liverpool, United Kingdom, (2)National Oceanography Centre, Southampton, United Kingdom, (3)National Oceanography Centre, Liverpool, United Kingdom, (4)Plymouth Marine Laboratory, Plymouth, United Kingdom, (5)Met Eireann, Dublin, Ireland, (6)CNRS - Institut des Géosciences de l'Environnement, Saint-Martin-d'Heres, France, (7)Met Office Hadley center for Climate Change, Exeter, United Kingdom, (8)Met Office Hadley Centre for Climate Change, Exeter, United Kingdom, (9)LOCEAN-IPSL, Sorbonne University, Paris, France