Variations in multiscale curvature distribution and signatures of LiDAR DTM errors
Article first published online: 24 JAN 2013
Copyright © 2012 John Wiley & Sons, Ltd.
Earth Surface Processes and Landforms
Volume 38, Issue 10, pages 1116–1134, August 2013
How to Cite
Sofia, G., Pirotti, F. and Tarolli, P. (2013), Variations in multiscale curvature distribution and signatures of LiDAR DTM errors. Earth Surf. Process. Landforms, 38: 1116–1134. doi: 10.1002/esp.3363
- Issue published online: 17 JUL 2013
- Article first published online: 24 JAN 2013
- Accepted manuscript online: 8 NOV 2012 01:16AM EST
- Manuscript Accepted: 23 OCT 2012
- Manuscript Revised: 19 OCT 2012
- Manuscript Received: 26 MAR 2012
- DTM quality;
- error modeling;
The development of high resolution LiDAR digital terrain models (DTMs) has enabled the exploration of the statistical signature of morphology on curvature distributions. This work analyzes Minimum Curvature distributions to identify the statistical signature of two types of LiDAR-DTM errors (outliers and striping artifacts) in the derived estimates, rather than morphology itself. The analysis shows the importance of modeling these errors correctly, in relation to the scale of analysis and DTM resolution, in order to have reliable curvature estimates. Nine DTMs of different morphological areas are considered, and grouped into a training dataset (without errors) and a test dataset (with errors). In the training dataset, the original DTMs are considered as true values; errors are then applied to these data. Minimum Curvature is computed at multiple scales from each DTM: changes in curvature distributions due only to morphology and scale are characterized from the original data; error effects are then identified from the datasets with simulated errors, and validated against the test dataset. The analysis shows that outliers and striping artifacts can be realistically simulated by heavily left tailed distributions. For DTMs without errors, the scale-dependent change in curvature distribution is primarily controlled by real morphology. When DTMs include errors, curvature distributions become controlled by these errors, whose propagation depends on error distribution, error spatial correlation, and the scale of analysis. This study shows that the curvature distributions are impacted upon differently by striping artifacts and outliers, and that these are clearly distinguishable from the signal of morphological features: a scale-dependent change in curvature distribution can therefore be interpreted as the signature of these specific errors, rather than morphology. Copyright © 2012 John Wiley & Sons, Ltd.