Aside from scientific enquiry, another appeal of this technology lies in its visual and artistic aspects. The images are captivating, and because the information has never been presented in this way before, they give us fresh insights which emerge at the confluence of science and art.
An aircraft or unmanned drone is usually used for LiDAR scans collecting up to 100,000 laser measurements per second. The data from scans can be used to create a set of points that show the 3D shape of the scanned objects, commonly referred to as a ‘point cloud’. Each point represents a specific location on the earth’s surface, in three dimensions: the conventional flat two-dimensional map position, plus the corresponding elevation or height. Geospatial information from satellites can be added to augment coverage.
Passing over any terrain taking LiDAR measurements achieves in minutes what could take hundreds of hours of manual surveying. Because it is so accurate and quick to collect, it can show changes over time, revealing transformations that might otherwise be missed. This is absolutely the case for the Rivers Alde and Ore, where change is constantly occurring, whether intertidal, seasonal, or across much longer time periods.
What can the measurements be used for?
LiDAR is widely used in planning and environmental management to support spatial decision-making and improve understanding of real-world features and phenomena.
Common applications include land use classification, environmental impact assessments and natural resource and climate change investigation. Data on sensitive habitats, water bodies or endangered species can be overlayed onto accurate and highly detailed surface elevation models. This can reveal existing and potential effects of flooding, river flow and erosion (of rivers and coasts), and the impact of human activity, including modifications to the built environment. LiDAR passes can assess forest inventory, tree canopy density, and monitor changes in marshland. LiDAR can even penetrate vegetation to the ground below by working out the difference between the first and last return of each emitted laser pulse.
For the complete article on river visualizations CLICK HERE.
