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If sunlight can reach the forest floor then so can LIDAR. An airframe with a LIDAR device scatter shots a medium angle "spotlight" of pulses at high frequency
by defrost 2y ago
If sunlight can reach the forest floor then so can LIDAR.
An airframe with a LIDAR device scatter shots a medium angle "spotlight" of pulses at high frequency downwards within an arc area of angles (straight down, a bit to the left, a bit to the right, a bit forward, etc.)
Of the tens of thousands of 'RAW' data points many reflect from top canopy leaf cover, many penetrate further, a lesser number reach the ground.
All the raw points are pipeline processed and the floor() of penetration is extracted from the fuzzy cloud that represents the canopy as a whole.
Ancient banks, levels, roads, et al show up where not eroded as per the image in the article.
- naikrovek 2y agoWhy do tree trunks not show up?
- defrost 2y agoStanding or fallen? .. and who says that fallen logs don't show up? Bear in mind that the final display is a processed data product with any number of artefacts smoothed, filtered, or cut away by a data processor.
- roughly 2y agoEven when eroded, the presence of straight lines in the eroded remains has typically been used to identify human-made structures.