Global warming, the effects of which are beginning to be felt in terms of heatwaves, summer droughts and winter floods, and their harmful consequences for living beings, is set to increase by a further +4° Celsius by 2100. Faced with rising temperatures, plant and animal species are seeing their original biotopes, which have become too hot, relocate ever further north. This shift of ecosystems towards colder latitudes is estimated at over 1 m per hour. Thus, the climate of our cities today will no longer be the same in 2100 when Paris will have a climate similar to that of Mexico, Japan, north Africa, Sicily or southern Spain. Human habitat is no exception to this climate shift, and most of the largest cities in Europe will have to cope with ever-higher temperatures, up to 50°c in summer. If the city is to remain inhabitable, if living things are to remain alive, if humans are to continue to live in the same region in 2100, architecture and the city must now be designed, adapted and built in a climate similar to that which currently exists further south.