Case Studies

MXR-CS-uqam 11/20 Previous studies have used stereo satellite imagery for estimating forest height by matching stereo images to produce digital surface models (DSM), but this was the first study to leverage stereo satellite imagery to measure individual tree heights from space. And it was a very successful first attempt. Residual errors for height were on average only 0.91 m. Basal area predictions had a 14% error, resulting in very acceptable accuracy for this methodology. industry The research team at UQAM chose to conduct their study in lichen woodlands, which are sparse forests in remote subarctic regions experiencing rapid warming due to climate change. The unusually mild weather is consequently lengthening the growing season which, among other shiing environmental factors, may have a significant global impact on carbon sequestration. The methodology from this study greatly increases the capacity of scientific investigators to measure forests in inaccessible regions. find out more The complete study, Estimating the Height and Basal Area at Individual Tree and Plot Levels in Canadian Subarctic Lichen Woodlands Using Stereo WorldView-3 Images, was published in the MDPI journal of Remote Sensing. For additional detail on the methodology and study results, please download the article at: https://www.mdpi.com/2072-4292/11/3/248. info@maxar.com maxar.com Rewarding results Future applications Overall, it's a breakthrough methodology that can be used to perform measurements from space to create "virtual field plots", an especially important note as Ice, Cloud, and Land Elevation Satellite-2 (ICESAT-2) begins one of its remote sensing mission: measure forest heights across the Earth and take stock of the vegetation in forests worldwide. With the incoming ICESAT-2 datasets, researchers should be able to efficiently measure forest height and estimate biomass at a global scale—contributing research to better understand climate change and its effects. The team believes that, because trees as small as 2 m could be measured in northern atitudes, the WorldView-3 methodology can also be used to study trees in open forests around the world, as well as other small objects, such as pylons or small buildings. 1Retrieved from: https://icesat-2.gsfc.nasa.gov/mission Short and narrow individual trees visible on a WorldView-3 panchromatic image.

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