A general view of London from the viewing platform of the Shard building, which has been photographed through plate glass, showing Britain's parliament, the Palace of Westminster and Big Ben's clock tower, right, visible through the haze and smog in London, Friday, April 10, 2015. Southern Britain and northern France are suffering high levels of air pollution due to stagnant air, though an Atlantic weather system will bring fresher conditions Saturday. (AP Photo/Alastair Grant)