SUTTON, ENGLAND - FEBRUARY 11:  A couple walk their dogs in sub-zero temperatures on February 11, 2012 in Sutton, England. Last night the Met Office recorded the coldest temperature so far this winter, -16C, was registered in Holbeach, Lincolnshire with many areas of England experiencing temperatures between -10C and -15C.  (Photo by Oli Scarff/Getty Images)