Stratosphere around at midlatitudes, and at about at the poles. Temperatures range from an average of near the tropopause to an average of near the mesosphere. Stratospheric temperatures also vary within the stratosphere as the seasons change, reaching particularly low temperatures in the polar night (winter). Winds in the stratosphere can far exceed those in the troposphere, reaching near in the Southern polar vortex. The mechanism describing the formation of the ozone layer was described by British mathematician Sydney Chapman in 1930. Molecular oxygen absorbs high energy sunlight in the UV-C region, at wavelengths shorter than about 240 nm. Radicals produced
History of the Berlin S-Bahn that were left opened after the strike do include: The 1980 incidents turned media and political attention toward what was left of West Berlin's S-Bahn network. The city government decided to enter negotiations with East Germany, which were finally successful. By contrast, during the same period, services on the S-Bahn in East Berlin were increased and new lines built as housing projects expanded eastward from the city centre. With most of the U-Bahn located in West Berlin, the S-Bahn became the backbone of the East Berlin transit network. The DR has purchased DR Class 270 as a result, where it