29 Jun 2026

Automated Workflows for Airborne Lidar and Photogrammetry Snow Depth Analyses

Abstract: Lidar and photogrammetry techniques provide highly accurate methods for mapping snow depth distribution. However, postprocessing point clouds for snow depth estimation is more complex compared to other earth science applications. This paper presents ice-road-copters (IRC), an open-source Python toolkit that facilitates processing and georeferencing of lidar and photogrammetry point clouds. Case studies demonstrate the tool’s utility across different sensors and platforms over a complex mountainous study area. Results show that a well-configured digital elevation model (DEM) filter effectively removes most noise and outliers from point cloud data. The Simple Morphological Filter (SMRF) generally perform well for ground segmentation but optimal results across diverse terrains may require site-specific tuning, particularly of the elevation threshold and scalar parameters in more complex landscapes. Different methods, including manual depth measurements or snow-free features, can be used to coregister DEMs, reducing vertical errors, eliminating large bias and achieving comparable accuracy to using exposed control surfaces. Derived snow depth rasters showed strong agreement with in situ probe measurements—root-mean-square error (RMSE) of less than 16 cm. Overall, IRC simplifies the transformation of raw point clouds into high-resolution DEMs and value-added snow products, facilitating efficient multitemporal analysis to support military and hydrology applications.

18 Sep 2025

Standard Operating Procedures for the Design, Construction, and Maintenance of Summer Roads and Trails, Drop Zones, and Firebreaks in Cold Regions

Abstact: As DoD investments across Alaska increase in response to DoD Arctic strategies, expanded training opportunities are necessary to enable the military to enhance their Arctic capabilities. In addition, wildfire management is increasingly important in the area as the summer season has expanded and warmed in recent decades. This report addresses the siting, design, construction, and maintenance of summer roads and trails, drop zones, and firebreaks on DoD lands in Alaska and other cold regions. It considers the harsh weather conditions, extreme seasonality, and remoteness of these environments, in addition to the general requirements of understanding the local environment, relevant risks, permitting, and regulations. The three types of linear infrastructure are assessed together as each involves the clearing of land and maintaining it as cleared, and therefore share common risks. This report summarizes best practices throughout the project lifecycle and synthesizes risk mitigation strategies informed by a comprehensive literature review and conversations with local training land managers. Using Fort Wainwright in Interior Alaska as an example, it provides Standard Operating Procedures (SOPs) to aid land managers and military unit leadership as they navigate challenges and opportunities in their increased use of these critical linear infrastructure types in high latitude environments.