“Extreme” rain follows global warming

Heavy rain is coming more of­ten as glob­al warm­ing con­tin­ues—an in­crease that is out­strip­ping sci­en­tists’ pre­dic­tions, ac­cord­ing to a stu­dy. The find­ings imply that warm­ing-induced changes in the glob­al wa­ter cy­cle could have more dras­tic im­pacts than ev­er im­ag­ined, its au­thors said.
The find­ings “re­veal a dis­tinct link be­tween rain­fall ex­tremes and tem­per­a­ture, with heavy rain events in­creas­ing dur­ing warm per­i­ods,” wrote the au­thors, Rich­ard P. Al­lan of the Uni­ver­s­ity of Read­ing, U.K. and Bri­an J. So­den of the Uni­ver­s­ity of Mi­ami, Fla. The re­port is to ap­pear in the Aug. 8 is­sue of the re­search jour­nal Sci­ence.Al­lan and So­den used sat­el­lite ob­serva­t­ions and com­pu­ter sim­ula­t­ions to study the rela­t­ion­ship be­tween trop­i­cal rain­fall and changes in Earth’s sur­face tem­per­a­ture and at­mos­pher­ic mois­ture. The ob­serva­t­ions point to a di­rect link be­tween warm­er cli­mate and an in­crease in ex­treme pre­cipita­t­ion based on both sat­el­lite da­ta and sim­ula­t­ions, they wrote. But the ob­served in­crease in ex­treme rain­fall is larg­er than the in­creases pre­dicted by sim­ula­t­ions, sug­gest­ing the pre­dic­tions are too low, they added.The pair warned that it’s cru­cial to find out the cause for this dis­crep­an­cy as soon as pos­si­ble in or­der to un­der­stand glob­al warm­ing and its ef­fects on the wa­ter cy­cle. In past stu­dies, sci­ent­ists have also sug­gested global warm­ing may wors­en the im­pact of hurri­canes and wild­fires.