Case Studies

Tree height, biomass and beyond What analysts and data scientists can do with high-resolution satellite imagery has increased in both value and number of applications. While we oen think of geospatial data informing defense and intelligence organizations, there are facets of commercial and academic instances as well. And recently, one academic research team proved a new methodology that will impact them all. A team from the Department of Geography at University of Québec at Montréal (UQAM) has successfully demonstrated that the height of single trees can be measured by spatial intersection of conjugate rays from a pair of WorldView-3 stereo images. Put simply, this is the first study that proves we can effectively measure and study such small objects from space.` The unique requirements for this study could only be met by imagery collected from WorldView-3, which proved to provide an accuracy close to that of field measurements–and more affordable than working on location. Utilizing highresolution satellite imagery reduces the time and resources typically spent on travel and transporting survey equipment to remote and oen difficult-to- reach places. THE BIG IMPACT OF SMALL OBJECTS: WITH THE DEPARTMENT OF GEOGRAPHY AT UQAM info@maxar.com maxar.com PROXY CALCULATIONS FOR BIOMASS Why measure tree heights? While this methodology can be applied in many diverse use cases, this study created a proxy for calculating the biomass of each individual tree. Woody biomass is roughly half carbon, which offsets the amount of CO2 in our atmosphere. To estimate biomass one can use the basal area of the tree, which can be predicted based on tree height. Individual basal area is the surface area of the cross section of a tree trunk at breast height. Plot-level basal area is a collective measurement of all trees in a defined area. case study Measuring the geolocation of trees in the field. "Traditionally, we have only estimated canopy heights and surfaces, but this is the first time we have been able to measure the height of individual trees. And this was only made possible by the very high photogrammetric accuracy and resolution of WorldView-3 images."

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