London is underwater. The Houses of Parliament, Buckingham Palace, St Paul's Cathedral and the Bank of England are all submerged. Far away, the West Antarctic and Greenland ice sheets have collapsed, triggering accelerated sea-level rise which, combined with a storm surge in the North Sea and a high spring tide, has led to water flooding over the Thames Barrier. Thousands of shops, offices, schools and houses are several feet deep in effluent-rich water.