An increasing number of cities are developing digital models. It becomes thus necessary to take into account changes over time. Interoperability and thus the use of standards is also recommended. In this paper,we propose a new method, based on CityGML to take into account changes in the objects which compose the city.This method is efficient for any kind of changes of the city objects(semantic,geometry,topology or appearance).We then propose an extension of our method in order to consider more frequent changes as it is the case with sensors data that can be linked with part of city objects.