Valerio Lucarini,a,b,c* Klaus Fraedrichd and Frank Lunkeitd aDepartment of Meteorology, University of Reading, UK bDepartment of Mathematics, University of Reading, UK cDepartment of Physics, University of Bologna, Italy dMeteorologisches Institut, KlimaCampus, University of Hamburg, Germany *Correspondence to: Valerio Lucarini, Department of Meteorology, University of Reading, Earley Gate, PO ...