Flight paths for flying squirrels in Espoo

The points where flying squirrels could fly over the main roads of Espoo have been investigated with the help of a point cloud. The end result is a set of lines in raster format (TIF, bitmap). The plane coordinate system is ETRS-GK25FIN (epsg:3879) and the vertical coordinate reference system N2000. When calculating the lines, the height has been calculated for each laser point. All trees over 2 m in height have been taken into account because they can be flown into. At the top and bottom of the trees, 0.5 m has been removed. The ratio of the tree level difference to the gliding distance is 1:3, so when the height difference in the trees is 10 m, the maximum flight distance is 30 m. The analysis does not take into account all terrain barriers, such as noise barriers. Possible structures should be checked in the terrain. The scanning data is from 2013.本研究借助点云（point cloud）技术，对芬兰埃斯波市（Espoo）内飞鼠可飞越主要道路的点位开展了调查。最终成果为一组栅格格式（TIF、位图）的线要素数据集。平面坐标系采用ETRS-GK25FIN（epsg:3879），垂直坐标参考系统为N2000。在计算该线要素时，已为每个激光点（laser point）解算高程信息。 所有高度超过2米的树木均被纳入分析范围，因其可作为飞鼠滑行起降的依托。在树木顶部与底部各扣除0.5米的高程范围。树木高差与滑行距离的比例为1:3，即当树木间高差为10米时，最大滑行距离可达30米。 本次分析未涵盖全部地形障碍物（如隔音屏障），地形中存在的潜在结构需另行核查。所用扫描数据采集于2013年。