26 Aug 2025

The Quick Response Toolbox User’s Guide

Abstract: Regional-scale beach morphology, volume, and shoreline changes are quantified using the Joint Airborne Lidar Bathymetry Technical Center of Expertise (JALBTCX) ArcGIS Python toolboxes. This user’s guide details the JALBTCX toolbox framework and the operation of the Quick Response Toolbox. A walkthrough for each individual step within the toolbox will be presented along with example data from Homer, Alaska. Best practices and example data and figures are included as additional documentation for new users.

20 Aug 2025

Examining the Impact of the 2007 Zaca Fire on the Long-Term Hydrological Recovery of the Santa Cruz Creek Watershed in Southern California

Abstract: This study focuses on the Santa Cruz Creek watershed in Southern California, an area severely impacted by the 2007 Zaca Fire. The region is representative of wildfire-prone Mediterranean-climate catchments. We assess long-term post-fire hydrological recovery using a novel dual approach: (1) simulating 16 storm events over a 23-year period to evaluate pre-fire, post-fire, and recovery conditions, and (2) directly comparing two similar storm events—one pre-fire and one during recovery—to isolate changes in watershed response. Hydrological modeling employed HEC-HMS with the Deficit and Constant Loss Method, the ModClark Transform Model, and the Linear Reservoir Baseflow Model. Remote sensing data, including Enhanced Vegetation Index and SERVES Soil Moisture, enhanced modeling and analysis. Vegetation cover, soil moisture, and several watershed parameters show substantial recovery after five years. EVI reached 84 % of pre-fire values, while initial soil moisture deficit, time of concentration, and storage coefficient each recovered to roughly 70 %. Fast baseflow exceeded pre-fire levels at 143 %, but slow baseflow declined to 20 %. Peak discharge and direct runoff volume declined from post-fire highs of 173 % and 136 % to 125 % and 84 % of pre-fire levels, respectively. Although vegetative conditions stabilize, watershed hydrology remains altered.

20 Aug 2025

Trade-offs Between Field and Remote Geomorphic Monitoring of Coastal Marsh Restoration Sites

Abstract: Coastal marsh restoration presents geomorphic monitoring challenges because these sites are often remote or inaccessible, and time and financial resources for field data may be limited. Yet, elevation and shoreline characteristics contribute to the overall health and longevity of coastal marshes. The expansion of Uncrewed Aircraft System (UAS) technology and new satellite platforms offer opportunities to complement ground-based geomorphic monitoring and overcome the challenges of traditional field methods. Here, we compare field-based and remote-sensing approaches to monitor two restored coastal wetlands in Louisiana. At Spanish Pass, methods for measuring site elevation, shoreline position, and shoreline geomorphic types were compared. Ground surveys strongly correlated with UAS-lidar digital elevation model (DEM) elevations (R2 = 0.97. UAS and satellite imagery were accurate to within 3 meters of field-shoreline positions, and UAS-lidar-derived shorelines had the lowest error. At LaBranche, UAS-lidar DEM data were paired with airborne lidar and legacy ground surveys to track temporal changes in elevation, indicating minimal elevation change. The study demonstrates the accuracy and utility of satellite and UAS remote sensing for monitoring shoreline positions and elevations but notes that shoreline classifications could be improved with additional quantification. These findings help practitioners assess the trade-offs and benefits of various monitoring methods.

2 Jul 2025

Remote Detection of Soil Shear Strength in Arctic and Subarctic Environments

Abstract: Soil shear strength affects many military activities and is affected significantly by plant roots. Unfortunately, root contribution to soil shear strength is difficult to measure and predict. In the boreal forest ecosystem, soil and hydrologic dynamics make soil shear strength less predictable, while the need for prediction grows due to the rapid changes occurring in this environment. Our current study objectives are to (1) observe possible aboveground vegetation indicators of soil shear strength variation across soils and other environmental heterogeneity, (2) observe possible image-based indicators of soil shear strength variation, and (3) identify the best remote-sensing data source for predicting soil shear strength variation. A total of 65 sites were sampled from a diversity of soil and vegetation types across interior Alaska and Ontario, Canada. Ground-collected data were analyzed to develop a predictive model, while a similar approach was undertaken with Sentinel-2 imagery. Results indicate that both ground-collected data and satellite imagery can reasonably predict boreal forest soil shear strength, with satellite imagery providing the higher predictive ability. A comparison of 10 m Sentinel-2 and submeter Maxar imagery indicated that Sentinel-2 provides a better prediction of soil shear strength.

16 Jun 2025

Estuarine Dams and Weirs: Global Analysis and Synthesis

Abstract: Estuarine dams and weirs are constructed in estuaries for blocking the salt intrusion, securing freshwater, and stabilizing upstream water levels. While they can provide many social benefits, they also alter physical and sedimentary processes. To address this, we perform and extensive remote sensing and literature analysis. Remote sensing was conducted based on a global river database of 1531 rivers representing the largest rivers cumulatively draining 85 % of the landmass discharging into the global ocean. It was found that 9.7 % of global estuaries and deltas are currently affected by estuarine dams or weirs acting as the upstream limit of salt, tide, or storm surge intrusion. Most estuarine dams and weirs are located at x = 0–100 km inland from the mouth and their discharge intervals can be continuous. They are found most in river mouths which are wave-dominated followed by tide-dominated and then river-dominated. They can cause significant changes to the quantity and timing of freshwater discharge, tides, stratification, turbidity, sedimentation, oxygen conditions, phytoplankton blooms, and fish migration. We propose a conceptual model for physical and geomorphological change in mixed wave- and river-dominated and tide-dominated estuaries with estuarine dams.

13 Jun 2025

Enhanced Route Reconnaissance—Generation 1

Abstract: The movement of soldiers and materiel across battlespace is critical to a successful military operation. Knowledge of the road network condition ensures safe and successful vehicle maneuver. This research focused on remote assessment of poor-quality paved road networks for vehicle maneuver using data products derived from three-dimensional point clouds. Point clouds were generated from lidar sensors deployed from ground and airborne platforms to enable engineering analysis of the pavement surface. A series of algorithms developed to extract roughness, grade, radius of curvature, and width along the road network ensured storage of information for graphical display. A vehicle speed lookup table was calculated by conducting computer simulations using the NATO Reference Mobility Model over a range of road parameters. The lookup table enabled determination of the maximum allowable speed for a given vehicle type associated with the extracted road parameters. A graphical interface, developed for displaying the percentage speed reduction as either red, amber, or green squares along the road network, provided visual assessments of road condition. This report summarizes developing a software suite to calculate and visualize speed reduction over a road network as a function of route geometry, condition, and vehicle type. The interface developed can aid in critical logistical decisions that influence the success of military maneuver operations.

9 Jun 2025

Review of Remote-Sensing Methods for Mapping Riparian and Submerged Aquatic Vegetation: Support for Ecosystem Restoration Monitoring and Flood Risk Management

Abstract: Riparian vegetation, defined as multilayered herbaceous and woody plant communities along river margins or bank edges, and freshwater submerged aquatic vegetation (SAV), described as rooted aquatic plants in shallow rivers, lakes, and estuaries, are key factors influencing the connection between river and floodplain systems. These vegetation types are often used as indicators of riparian health. Current data on riparian vegetation and SAV are essential for addressing future water resource needs, particularly for restoration monitoring and flood risk management. The US Army Corps of Engineers (USACE), as the federal government’s largest water resources development and management agency, requires updated monitoring and assessment methods to support the development, utilization, and conservation of water and related resources. Assessing large riparian corridors involves characterizing baseline conditions, habitat extents, vegetation patterns, and health. Vegetation and habitat data are critical for evaluating the effects of project operations, resource management, and restoration outcomes downstream from USACE dams. However, obtaining such data across large, dynamic, and inaccessible river reaches is challenging. Integrating field-based techniques with remote-sensing technology offers opportunities to map larger areas comprehensively and adapt to future water resource needs. This report reviews re-mote sensing methods for mapping riparian and SAV habitats with emphasis on vegetation characteristics.

6 May 2025

Applications of the CRREL–-Geometric Optics Snow Radiative Transfer (GOSRT) Model: Incorporating Diffraction and Simulating Detection of Buried Targets

Abstract: Radiative transfer through a snow surface within the visible and near infrared (NIR) spectra is complicated by the shape, size, and configuration of the snow grains that comprise the snow surface. Ray-tracing and photon-tracking techniques combined with 3D renderings of snow resolved at the microscale have shown promise as a means to directly simulate radiative transfer through snow with no restrictions on the snow grain configuration. This report describes and evaluates the US Army Cold Regions Research and Engineering Laboratory (CRREL) Geometric Optics Snow Radiative Transfer (GOSRT) model. In particular, we describe the incorporation of the diffraction process into the photon-tracking framework and evaluate how accurately the model simulates the spectral albedo of targets buried within the snow. We find that the model simulated spectral albedo is little affected by the incorporation of diffraction for most applications. However, there are nonnegligible impacts on simulated albedo for small grains in the NIR due to a reduction in forward scattering. We conclude by recommending that diffraction is neglected in CRREL–GOSRT for most cases, as including it substantially increases the computational expense with minimal impacts on the result. Finally, we show that buried targets are only distinguishable for very shallow snowpacks.

16 Apr 2025

Sensor Fusion for Aerial Robotic Systems

Abstract: As uncrewed aerial vehicle (drone) use expands across industries so also does the complexity of sensor payloads. At present, there are no commercially available products for the management and fusion of multisensor data. Sensor Fusion for Aerial Robotic Systems (SFARS) is a sensor agnostic, modular platform for intelligent multisensor data fusion and processing. At the time of writing, SFARS exists as a root codebase, a PC application for processing of previously collected drone data and as a prototype hardware platform for real-time drone deployment. This report serves as a technical users guide to the design, development, and implementation of the suite of SFARS software.

3 Feb 2025

Overview of a Rapid Discrete Infrared Acquisition System and Method for Automated Behavioral Analysis of Multiple Emissive Objects

Purpose: Many animal species form congregations on the landscape. These concentrations of animals provide an opportunity for biologists to conduct efficient population monitoring efforts. While general use of these sites is easy to document, continual monitoring is often problematic due to limited resources (time, expertise, etc.), potential for human disturbance on animal population and behavior, and an inability to determine an accurate assessment of counts. To allow for accurate and efficient assessment of animal numbers and usage of an area, an automated technology has been developed to monitor and characterize large animal concentrations. This automated technology provides information on population size, movement behavior characteristics, and other behavioral aspects of the target species.