This paper presents a method for strong scatterers change de- tection in synthetic aperture radar (SAR) images based on a decomposition for multi-temporal series. The formulated de- composition model jointly estimates the background of the series and the scatterers. The decomposition model retrieves possible changes in scatterers and the date at which they oc- curred. An exact optimization method of the model is pre- sented and applied to a TerraSAR-X time series.