1. A method of assessing changes to a region, the method comprising: receiving elevation data indicative of a region; generating a spatial model of the region based on the elevation data; identifying based on the spatial model a first representation of a portion of the region, wherein the first representation of the portion of the region is indicative of the portion of the region at a first time; and determining a difference between the first representation of the portion of the region and a second representation of the portion of the region, wherein the second representation of the portion of the region is indicative of the portion of the region at a second time.