31 Oct 2023

Stage Frequency Analysis from Snowmelt Runoff near Utqiaġvik, Alaska

Abstract: For the village of Utqiaġvik, located at the North Slope of Alaska, a stone-armored revetment along the coastline is proposed to reduce coastal erosion. The inner drainage capacity of the revetment must be sufficient to handle seasonal runoff from snowmelt. For this effort, we investigated the snowmelt runoff and the hydraulic impact at the watershed outlet using numerical snow and hydraulic modeling of the study area. We validated the snow model results by comparing simulated snow water equivalent (SWE) values to field measurements. Additionally, the snow model was validated using satellite-based Moderate Resolution Imaging Spectroradiometer (MODIS) snow-covered area (SCA) products and time-lapse camera imagery during snowmelt. Our results indicate that the simulated SWE and snowmelt dates agree closely with measured values. The timing of modeled runoff onset was less accurate due to natural processes that delay snowmelt runoff such as snow dams and refreeze. The effect of the uncertainty from both runoff timing and volume was addressed with a Monte Carlo simulation of stage-frequency curves for the lagoons that receive snowmelt runoff. These stage-frequency curves can be used directly in the design of outlet, drainage or discharge structures for the proposed revetment.

20 Oct 2023

Phase I Geothermal Opportunities Assessment of the Delta Junction Area, Alaska

Abstract: To enhance energy resilience at military installations in Interior Alaska, we are exploring geothermal energy, which harvests Earth’s heat to provide thermal energy, electricity, or both. Parts of Interior Alaska have high subsurface heat flow, likely related to high-heat-producing granites. While electric load is usually the focus of energy resilience; in cold regions, the thermal load dominates energy demand, and operations can be sensitive to it. A local geothermal energy source enhances energy resilience by providing baseload energy and lessening supply chain demand. Geothermal energy technology is mature and often economical, but resource location and assessment remain challenging. We present exploration methods for a geothermal feasibility study for Interior Alaska and Phase I prefeasibility study results assessing opportunities to develop geothermal at Fort Greely, Alaska. We present possible geothermal resource types, their potential uses, likelihood of existence, and development risk. We also present custom methodology for locating the resources, associated uncertainty, and the impact of finding each resource. Phase I shows geothermal at Fort Greely survives the elimination test. Investment into a Phase II field study to address knowledge gaps should consider the higher risk in comparison to other geothermal plays due to new methodology and sparse existing data.

29 Sep 2023

Arctic Seed Sterilization and Germination

Abstract: We conducted growth chamber experiments to overcome challenges of native seed germination relating to disease and germination time. We selected five northern species, Eriophorum vaginatum, E. virginicum, Anemone patens var. multifida, Polemonium reptans, and Senecio congestus, for their native ranges and commercial-nursery availability. Recommended stratification time for each species was either unknown or a minimum of 60 days. Seeds were sterilized with 70% ethanol, 10% hydrogen peroxide, or UVC light to identify which method most effectively prevented pathogen infection. To determine if stratification time could be reduced, seeds underwent a 30-day cold, moist stratification. We tested which growth medium was most conducive to germination of the sterilized, stratified seeds: filter paper or sterilized potting soil. In a separate experiment, we tested if three different levels of gibberellic acid (GA3; 0, 500, and 1000 ppm) could reduce stratification time to 15 days. The 70% ethanol was effective in a seed surface sterilization; an average of 84% of all seeds for all species treated showed no contamination. Germination following a 30-day cold, moist stratification was unsuccessful for most species tested in both growth media. Here, 1000 ppm GA3 with a 15-day cold, moist stratification showed considerable success with P. reptans.

29 Sep 2023

Microbial Activity in Dust-Contaminated Antarctic Snow

Abstract: During weather events, particles can accumulate on the snow near the Pegasus ice and Phoenix compacted-snow Runways at the US McMurdo Station in Antarctica. The deposited particles melt into the surface, initially forming steep-sided holes, which can widen into patches of weak and rotten snow and ice. These changes negatively impact the ice and snow runways and snow roads trafficked by vehicles. To understand the importance of microbes on this process, we examined deposited dust particles and their microbial communities in snow samples collected near the runways. Snow samples were analyzed at the Cold Regions Research and Engineering Laboratory where we performed a respiration study to measure the microbial activity during a simulated melt, isolated microorganisms, examined particle-size distribution, and performed 16S rRNA gene sequencing. We measured higher levels of carbon dioxide production from a sample containing more dust than from a sample containing less dust, a finding consistent with viable dust-associated microbial communities. Additionally, eleven microorganisms were isolated and cultured from snow samples containing dust particles. While wind patterns and satellite images suggest that the deposited particles originate from nearby Black Island, comparisons of the particle size and chemical composition were inconclusive.

29 Sep 2023

Plant Phenology Drives Seasonal Changes in Shear Stress Partitioning in a Semi-Arid Rangeland

Abstract: Accurate representation of surface roughness in predictive models of aeolian sediment transport and dust emission is required for model accuracy. While past studies have examined roughness effects on drag partitioning, the spatial and temporal variability of surface shear velocity and the shear stress ratio remain poorly described. Here, we use a four-month dataset of total shear velocity (u*) and soil surface shear velocity (us*) measurements to examine the spatiotemporal variability of the shear stress ratio (R) before, during, and after vegetation green-up at a honey mesquite (Prosopis glandulosa Torr.) shrub-invaded grassland in the Chihuahuan Desert, New Mexico, USA. Results show that vegetation green-up, the emergence of leaves, led to increased drag and surface aerodynamic sheltering and a reduction in us* and R magnitude and variability. We found that us* decreased from 20% to 5% of u* as the vegetation form drag and its sheltering effect increased. Similarly, the spatiotemporal variability of R was found to be linked directly to plant phenological phases. We conclude that drag partition schemes should incorporate seasonal vegetation change, via dynamic drag coefficients and/or R, to accurately predict the timing and magnitude of seasonal aeolian sediment fluxes.

29 Sep 2023

Enhancing Building Thermal Comfort: A Review of Phase Change Materials in Concrete

Abstract: The DoD accounts for over 1% of the country's total electricity consumption. However, DoD bases heavily rely on vulnerable commercial power grids, susceptible to disruptions from outdated infrastructure, weather-related incidents, and direct attacks. To enhance energy efficiency and resilience, it is imperative to address energy demand in buildings, especially heating and cooling. This study focuses on phase change materials (PCMs) incorporated into concrete to enhance thermal control and reduce energy consumption. Though PCMs have shown promise in heat transfer and energy storage applications, their integration into concrete faces challenges. Concerns include potential reduction in compressive strength, impacts on workability and setting time, effects on density and porosity, durability, and higher cost than traditional concrete. This report examines current obstacles hindering the use of PCMs in concrete and proposes opportunities for extensive research and application. By selecting appropriate PCMs and additives, comparable strength to control samples can be achieved. Moreover, specific techniques for incorporating PCMs into concrete demonstrate greater effectiveness. Embracing PCMs in concrete can significantly contribute to energy-efficient and resilient DoD installations.

28 Sep 2023

Incorporating Advanced Snow Microphysics and Lateral Transport into the Noah-Multiparameterization (Noah-MP) Land Surface Model

Abstract: The dynamic state of the land surface presents challenges and opportunities for military and civil operations in extreme cold environments. In particular, the effects of snow and frozen ground on Soldier and vehicle mobility are hard to overstate. Current authoritative weather and land models are run at global scales (i.e., dx > 10 km) and are of limited use at the Soldier scale (dx < 100 m). Here, we describe several snow physics upgrades made to the Noah-Multiparameterization (Noah-MP) community land surface model (LSM). These upgrades include a blowing snow overlay to simulate the lateral redistribution of snow by the wind and the addition of new prognostic snow microstructure variables, namely grain size and bond radius. These additions represent major upgrades to the snow component of the Noah-MP LSM because they incorporate processes and methods used in more specialized snow modeling frameworks. These upgrades are demonstrated in idealized and real-world applications. The test simulations were promising and show that the newly added snow physics replicate observed behavior with reasonable accuracy. We hope these upgrades facilitate ongoing and future research on characterizing the effects of the integrated snow and soil land surface in extreme cold environments at the tactical scale.

27 Sep 2023

Evaluation of Non-Destructive Testing (NDT) Methods for Wood Power Poles

Abstract: This technical report aims to test the effectiveness of several non-destructive testing (NDT) technologies on wood utility poles to detect deterioration. The project will assess commercially available devices using sound velocity and drilling resistance methods for in-field measurements. The goal is to extend the lifetime of wood poles, prevent unexpected failure, and enhance their in-service life beyond the current 75-year expectation. Despite the benefits of wood poles, it is difficult to obtain reliable deterioration metrics on in-service poles, which can lead to premature decommissioning or pole failure. NDT methods have been developed to replace labor-intensive methods, but none have been largely adopted in common practice. Therefore, creating a database of validated data would expedite adoption. Integrating precise and efficient wood utility pole NDT can increase installation energy resiliency and facility sustainment in a fiscally responsible way, ensuring high standards of delivery of services.

26 Sep 2023

Isolation and Characterization of Bacterial Isolates from Alaskan Permafrost for Synthetic Biology Applications

Abstract: Operations in the Artic and other cold regions require technologies that can perform reliably under extreme cold conditions. Permafrost and frozen soils harbor a wide range of microorganisms that have adapted to extremely low temperatures and have unique metabolic capabilities relevant to military operations and that could be exploited to develop biotechnologies optimized for cold environments. Cold-tolerant bacteria (psychrophiles and psychrotrophs) are critical to the development of synthetic biology technologies meant to work in cold environments like the Arctic. Using bacteria isolated from Alaskan permafrost, we applied an experimental pipeline to test the best candidates for use as biological platforms, or chassis, for low-temperature synthetic biology. Since synthetic biology constructs will perform only as well as their chassis, it is critical that circuits expected to perform under extreme cold conditions are housed in chassis that are adapted to those conditions. We identified one permafrost isolate, PTI8, related to Rhodococcus fascians, that is capable of growing from −1°C to at least 25°C and which we experimentally confirmed to uptake and express the broad host range plasmid pBTK519, suggesting PTI8 is a candidate for use as a novel cold-adapted chassis for synthetic biology.

13 Sep 2023

Cold Impacts on Vehicle Electrical Systems: Developing a Baseline for Cold Testing Military Vehicles

Abstract: Low temperatures can significantly affect vehicle operation. While many of the effects, like increased fluid viscosity and decreased battery capacity, are well documented, the impacts on the electrical system as a whole are not. The objective of this study was to investigate the impacts of temperature on the electrical systems of select military vehicles and to develop a baseline for future testing. A High Mobility Multipurpose Wheeled Vehicle (HMMWV), a Heavy Expanded Mobility Tactical Truck (HEMTT), and a four-person diesel Polaris MRZR D4 were subjected to 15°C, 0°C, and −15°C temperatures while the loads on the battery and alternator were monitored. The HMMWV and MRZR were able to start on the first try for all tests. They both showed a slight increase in vehicle load current draw from the alternator as temperatures decreased. Future testing with more iterations and at lower temperatures will help identify clearer trends and improve testing procedures. As the Army becomes more reliant on electronic systems, it is becoming increasingly important that we understand how various climates will impact them.