The premise of the movie is incorrect. The ozone layer blocks harmful UltraViolet C light, which is a very important function to most life on this planet, since UVC destroys DNA (The higher the frequency the worse it is. UVA gives you a tan, UVB gives you melanoma, UVC kills everything), but Ozone is not a barrier preventing the cold of the mesosphere from reaching the ground ... that's mainly Air Pressure and Convection ... Warmer air rises, and air moves from high pressure to low pressure areas.
Ozone is an oxygen molecule with three single linked oxygen atoms in a triangle rather than two double linked atoms, and the photo-chemical reaction of oxygen to ozone and back is what absorbs the UVC wavelength energy. The ozone layer is between 12 and 19 miles above the earth, but if it were compressed to the atmospheric pressure at sea level, it would only be about 3 millimeters thick. The danger in a "rift" or hole in the ozone layer is rapid sunburn, possible genetic damage/mutation, or death depending on exposure level. for many years there has been a hole in the ozone layer in the southern hemisphere. it expands and contracts yearly, and most years it slowly moves around between Antarctica and the southern ocean and during other years it spans the entire Antarctic continent.
Ozone is an oxygen molecule with three single linked oxygen atoms in a triangle rather than two double linked atoms, and the photo-chemical reaction of oxygen to ozone and back is what absorbs the UVC wavelength energy. The ozone layer is between 12 and 19 miles above the earth, but if it were compressed to the atmospheric pressure at sea level, it would only be about 3 millimeters thick. The danger in a "rift" or hole in the ozone layer is rapid sunburn, possible genetic damage/mutation, or death depending on exposure level. for many years there has been a hole in the ozone layer in the southern hemisphere. it expands and contracts yearly, and most years it slowly moves around between Antarctica and the southern ocean and during other years it spans the entire Antarctic continent.
During the opening few minutes you hear a radio broadcast saying "It's a balmy 74 degrees here in Hobart ...." Australia uses the Celsius/Centigrade system, and has done so since 1966.
The story occurs in the spring at Hobart, and yet when the Ice fog hits London and Moscow, it appears to be summer there, when of course the northern hemisphere would be in the autumn heading for winter.
The events of the movie take place on a working/school day, and show the Salamanca Markets in operation. The Salamanca Markets are only open on a Saturday.
The two islands hit as the cloud travels towards Hobart are fictional or mislocated. There is no Cromwell Island, and Rakino Island, far from being 476 miles south of Hobart is actually 1500 miles east, near Auckland in the Hauraki Gulf.