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This study has applied an integrated airborne laser scanning (ALS) and geographic information systems (GIS) technique to estimate urban tree damages caused by an ice storm that affected the City of Norman, Oklahoma between 8 and 11th of December, 2007. Pre- and post-storm ALS data were collected and processed using GIS. The pre-storm ALS data was used to create a digital elevation model (DEM) and the pre-storm digital surface model (DSM) while the post-storm DSM was created from post-storm ALS data. The DEM were subtracted from the two DSMs to create the pre- and post-storm canopy height models (CHMs). Individual and grouped trees were then separated using a combination of Koukoulas and Blackburn and local maxima tree extraction algorithms. Finally, differences in height and canopy diameter between the pre- and post-storm CHMs within the extracted trees were calculated to measure …