7 Apr 2026

Vehicle and Unpiloted Aerial System Interferometric Synthetic Aperture Radar Data Collection and Processing

Abstract: Interferometric synthetic aperture radar (InSAR) systems have a wide breadth of cold regions science and engineering applications such as determining snow water storage, permafrost thaw induced subsidence and frost heave of the active layer, and ground slope and infrastructure stability in permafrost dominated regions. Here, we present project planning, data collection, and processing workflows from two L-band InSAR systems, L-band SAR (GS-L) and UAS-mounted (GLSAR). The GS-L platform is integrated on a mobile, ground-based platform while the GLSAR is integrated on an uncrewed aerial system (UAS). We describe the postprocessing steps to produce radar back-scattered power and interferograms for the analysis of subsurface and near-surface phenomena. These steps are common to all the sensors discussed in this report and include kinematic postprocessing of the sensor positions, focusing on the raw radar returns in range and azimuth to form the radar image, and calculating the interferometric phase between acquisitions. With examples from each platform, we demonstrate the utility of these InSAR sensors and discuss acquisition scenarios in which either ground-based or UAS-borne systems may deliver higher-quality information from one another.

2 Apr 2026

Analyzing Historical Snow Trends in Interior Alaska

Abstract: This study examines 40 years (water years 1982–2021) of snowpack characteristics to consider its hydrological implications in the 5350 km² Chena River basin. Using observations and a fine-scale physics model, we analyzed trends of snow water equivalent (SWE), snow onset and disappearance, and snow cover duration (SCD). New hydrological insights for the region: Results indicate a decline in SWE across the modeled domain, averaging a decrease of 3 mm per decade, with larger decreases (up to 10 mm per decade) at lower elevations. While domain-averaged SWE trends were not statistically significant, observed SCD showed statistically significant decreases: - 5.2, - 5.0, and - 4.4 days per decade at Teuchet Creek, Fairbanks F.O., and Little Chena Ridge, respectively. Notably, observations at SNOTEL stations and modeling revealed no statistically significant change in domain-averaged Rain-on-Snow (ROS) events over the 40-year period, contrasting some regional future estimates of increased ROS frequency. Peak streamflow did not consistently correlate with peak SWE levels, suggesting that other environmental factors such as ROS events and rapid temperature increases (e.g., a 10◦C spike observed in 1992) are key drivers of hydrological outcomes. These findings improve understanding of complex subarctic hydrological processes impacting permafrost and highlight the need for adaptive water resource management to mitigate multi-factor risks like flooding and wildfire, requiring proactive planning.

2 Apr 2026

Storylines for the 1997 New Year’s Flood: The role of Watershed Antecedent Conditions and Future Warming in Shaping Discharge in the Truckee River Watershed

Abstract: The 1997 New Year’s flood was among the most devastating floods in the Truckee River watershed located in western Nevada. This event resulted from complex interactions of flood drivers, such as extreme precipitation, wet antecedent watershed conditions, warm temperatures and rapid snowmelt. We leveraged simulated forcings from the regionally refined mesh capabilities of the Energy Exascale Earth System Model (RRM-E3SM) and a process-based hydrological model to recreate the 1997 New Year’s flood for the Truckee River watershed across four climate warming levels ranging from the current temperatures to + 4◦ C. For each scenario, we conducted ensemble simulations with the same forcing but with 100 different seasonal watershed antecedent conditions, which were randomly sampled from long-term hydrological simulations. The results show that the 1997 New Year’s flood can be reproduced or exceeded consistently only when the antecedent watershed conditions are wet, specifically when streamflows are above the 75th percentile of the climatological value. There is negligible change in ensemble mean peakflows for Truckee River near Reno; however, there are increases of 18% and 14% under the warming levels of + 3◦ C and + 4◦ C, respectively. The increases in peakflows under future climate warming are attributed to wetter antecedent watershed conditions and enhanced snowmelt. Furthermore, the largest increases in peakflows occur at small, high-elevation headwater basins along the Sierra Nevada crest. This study highlights that changes in extreme flood events will result from the complex interplay of multiple flood drivers. It also demonstrates the potential of storyline approaches to analyze future realizations of these extreme events under different climate scenarios.

30 Mar 2026

Water Injection Dredging—Screening for Suitability: Research and Development of Screening Criteria to Determine the Suitability of Water Injection Dredging

Abstract: Innovative technologies for sediment management could reduce dredging costs and enhance benefits from sediment resources. Water injection dredging (WID) has the potential to improve sediment management in channels and reservoirs in the United States, but conditions for feasibility and favorable applications must first be established. WID works by fluidizing a sediment bed, causing it to flow down gradient or to spread as a density current. Fluidization testing on a range of sediments shows that the liquidity index might be an effective indicator of a sediment’s susceptibility to fluidization via WID. To assess the anticipated effectiveness of WID, a series of experiments were conducted to evaluate the fluid mud properties of sediment from Tuttle Creek Lake, Kansas, where WID has been proposed for reservoir management. Laboratory investigations were conducted to evaluate settling characteristics, viscosity, and angles of repose of the fluid mud over a range of concentrations. Large-scale flume experiments were also conducted to track the velocity and slope of the density current. Results were used to evaluate the flow characteristics of a density current generated by WID.

26 Mar 2026

Complete Genomic Sequences of Nine Bacillota Isolated from Alaskan Permafrost

Abstract: A total of nine Bacillota bacteria were isolated from Alaskan permafrost, and complete genomic sequences were obtained via hybrid assembly of long and short reads (Oxford Nanopore and Illumina paired-end sequencing, respectively). These genomes highlight the diversity of Arctic Bacillota and their potential applications in biotechnology.

26 Mar 2026

Lifecycle Cost and Benefit Analysis for Parcel-Scale Implementation of Green Stormwater Infrastructure

Abstract: Green stormwater infrastructure (GSI) is commonly implemented to reduce excess stormwater runoff while also producing secondary environmental, health, and aesthetic benefits. However, GSI is sometimes perceived to be cost prohibitive for limited-budget site development projects. This study used lifecycle cost analysis (LCCA) and benefit-cost analysis (BCA) to investigate the cost-effectiveness of GSI combined with conventional stormwater infrastructure for a proposed parcel development site in Oxford, Mississippi, USA. Hydrologic modeling was conducted for a conventional underground detention facility as well as three GSIs (permeable pavement, rain garden, and grassy ditch), all of which met regulatory runoff attenuation targets for the site. The LCCA considered capital and operation and maintenance (O&M) costs. Benefits were estimated under six categories – water, energy, climate, air quality, health, and community – based on existing tools for economic analysis of low impact development (LID). Economic benefits and costs over different scenarios of project lifecycles were compared using the present value (PV) approach in the benefit cost analysis (BCA). The lifecycle costs of two of the three GSIs (rain garden and grassy ditch) were lower than for the conventional alternative alone. However, in all three GSI cases, the long-term benefits of GSI features outweighed the costs. The methodology presented can be adapted to other locations to inform analyses of lifecycle costs and benefits and identify GSI and hybrid infrastructure options that are financially and environmentally feasible.

26 Mar 2026

Development of a Three-Dimensional (3D) Hydrodynamic, Salinity, and Sediment Transport Model of the San Francisco Bay

Abstract: The US Army Engineer Research and Development Center, Coastal and Hydraulics Laboratory (ERDC-CHL), has developed the multimodule Adaptive Hydraulics (AdH) model for San Francisco Bay, incorporating hydrodynamics, salinity, and sediment transport. This model supports the US Army Corps of Engineers San Francisco District in navigation and sediment management, particularly for the development of a Regional Dredged Material Management Plan to assess dredging methods and placement alternatives. San Francisco Bay is a dynamic estuary shaped by strong tidal currents, seasonal freshwater inflows, and complex sediment transport. As a key hub for international maritime trade, its federal navigation channels require regular maintenance dredging. Dredged sediment plays a crucial role in sustaining mudflats, tidal marshes, and intertidal habitats that mitigate coastal flooding and provide ecological benefits. This report documents the development, application, and validation of the AdH-3D model for 2022, demonstrating its ability to reproduce observed hydrodynamic, salinity, and sediment conditions. It details the model setup, boundary conditions, and validation, ensuring its reliability for informing sediment management and navigation planning. The model serves as a valuable tool for evaluating long-term sediment fate and optimizing regional dredging strategies.

24 Mar 2026

LaGrange Lock and Dam Navigation Study: Ship Simulation Results

Abstract: Located at River Mile 80.2, approximately 8 mi south of Beardstown, Illinois, the LaGrange Lock and Dam is a wicket gate structure with a single tainter gate to control pool elevation. LaGrange was constructed in the 1930s to aid navigation on the Illinois River. Due to increased commercial traffic, its existing 600 ft lock is now inadequate. To address this, the US Army Corps of Engineers' Rock Island District and the Engineer Research and Development Center (ERDC) studied the feasibility of adding a new 1,200 ft lock chamber. Initial physical model studies were conducted between 2009 and 2010 and continued in 2023. In 2024, the Coastal and Hydraulics Laboratory (CHL) used the ERDC Watercraft and Ship Simulator for a feasibility study focusing on the approaches to the new lock. The goal was to assess the navigability of the proposed design under various conditions. By analyzing simulator data and pilot feedback, CHL worked to confirm the design's feasibility and ensure its construction would not adversely affect the existing structure, which will remain as an auxiliary chamber.

24 Mar 2026

Intraspecific Variation in Rapid Cold Hardening and Acclimation of the Adventive Parrot’s Feather Weevil, Phytobius (=Parenthis) Vestitus, in the Southern USA

Abstract: Plasticity in thermal tolerance, expressed through acclimation or rapid cold hardening, for example, provides organisms with a mechanism to deal with unexpected and often rapid changes in the thermal environment. Spatial variation in response to high or low temperatures may occur due to evolutionary adaptation, particularly if a fitness increase coincides with the ability to respond quickly to environmental change. Thermal tolerances of beneficial insects used for biological control dictate where and under what thermal conditions the insects will provide value to management programs. We investigated two aspects of thermal phenotypic plasticity in response to thermal conditions using four populations of the adventive parrot’s feather weevil, Phytobius vestitus, from the southern USA. At low temperatures, we determined the presence and variation in rapid cold hardening in one of the four populations using two temperature ramping rates. In contrast, at high temperatures, all P. vestitus populations displayed a significant heat acclimation response, documented as elevated loss of motor control and motor function temperatures after acclimation. Thus, observed patterns of plasticity differed between high and low temperatures and among source populations. These results demonstrate the presence of geographic variation in phenotypic plasticity in response to thermal environments and emphasizes the need to consider plasticity when selecting climate-adapted populations of biological control agents.

24 Mar 2026

Developing a Habitat Suitability Index with Field Data and Hydraulic Models

Abstract: Linking habitat availability with hydraulic models integrates river engineering in the ecological field. Field observation for species presence and physical habitat availability mapping is inherently limited due to time and access constraints for field data collection. This study leverages hydraulic modeling to supplement larval fish population monitoring data, effectively expanding mapped physical habitat and allowing for monitoring bias analysis. The inundation extents and character of streamflow from hydraulic modeling were used to refine habitat suitability indices relative to total habitat availability from discrete fish monitoring events. Given the flexibility in hydraulic modeling to simulate a range of flows, the habitat suitability index is then translated to an effective habitat curve according to areal inundation and hydrologic frequency. With this framework, forecasting the impacts of long-term trends, such as geomorphic or hydrologic change, can be reasonably and quantitatively assessed. This manuscript uses a case study of Rio Grande silvery minnow monitoring at restoration sites where the floodplain has been lowered via earthwork. Comparisons are made for habitat suitability indices developed from field observation data alone and field observation supplemented by hydraulic modeling. Known biases of field sampling data were confirmed based on simulated hydraulic conditions across entire restoration sites. In the case of Rio Grande silvery minnow, a heavily studied species, such field monitoring biases are an effective use of resources. However, this framework may be helpful for assessing alternative management approaches and monitoring strategies of species that are less studied.