By using satellite data from the Copernicus project Sentinel 2 which has an infrared sensor, we are trying to assess the health of the urban trees by using time series analysis. Chlorophyll, a health indicator pigment, strongly absorbs visible light, and the cellular structure of the leaves strongly reflects near-infrared light. The idea is to use this phenonemon to develop a tree vigour index which visualize and quantify the trend of the tree health during the last 5 years. By identifying the beginning and end of the growth season through satellite imagery we will be able to monitor tree health from above.