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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 181 records · Page 10
All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

AmeriFlux CA-RBM Richmond Brackish Marsh

This is the AmeriFlux version of the carbon flux data for the site CA-RBM Richmond Brackish Marsh. Site Description - This site is a tidal brackish marsh on the southern side of the Sturgeon Bank Wildlife Management Area (WMA) in Richmond, British Columbia, Canada. This area is situated within the estuary of the Fraser River. The total area of Sturgeon Bank WMA is 5,152 ha, of which the tidal marsh area is 205 ha. The southern of the WMA is characterized as a brackish marsh, which transitions to a salt marsh as you go north. Human development has influenced this area for almost 200 years. Human activities in this area began in the early 1800s, which included dredging, dyke and entrainment structures, agriculture, and other uses. The areas were designated as WMA in 1998. This area experiences a semidiurnal tidal cycle. The flux tower is located near the southern edge of the marsh, where the dominant species is cattail (Typha latifolia), with a canopy height of 160 cm. The tower is in a high marsh system and was installed to analyze energy, H2O, CO2, and CH4 fluxes on June 1, 2022.

Knox, Sara [The University of British Columbia]↗
DOE OSTI2026

AmeriFlux FLUXNET-1F CA-RBM Richmond Brackish Marsh

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site CA-RBM Richmond Brackish Marsh. This is the FLUXNET version of the carbon flux data for the site CA-RBM Richmond Brackish Marsh produced by applying the standard ONEFlux (1F) software. Site Description - This site is a tidal brackish marsh on the southern side of the Sturgeon Bank Wildlife Management Area (WMA) in Richmond, British Columbia, Canada. This area is situated within the estuary of the Fraser River. The total area of Sturgeon Bank WMA is 5,152 ha, of which the tidal marsh area is 205 ha. The southern of the WMA is characterized as a brackish marsh, which transitions to a salt marsh as you go north. Human development has influenced this area for almost 200 years. Human activities in this area began in the early 1800s, which included dredging, dyke and entrainment structures, agriculture, and other uses. The areas were designated as WMA in 1998. This area experiences a semidiurnal tidal cycle. The flux tower is located near the southern edge of the marsh, where the dominant species is cattail (Typha latifolia), with a canopy height of 160 cm. The tower is in a high marsh system and was installed to analyze energy, H2O, CO2, and CH4 fluxes on June 1, 2022.

Knox, Sara [The University of British Columbia]↗
DOE OSTI2020

SMART Mobility. Urban Science Capstone Report

The U.S. Department of Energy’s Systems and Modeling for Accelerated Research in Transportation (SMART) Mobility Consortium is a multiyear, multi-laboratory collaborative, managed by the Energy Efficient Mobility Systems Program of the Office of Energy Efficiency and Renewable Energy, Vehicle Technologies Office, dedicated to further understanding the energy implications and opportunities of advanced mobility technologies and services. The Urban Science (US) Pillar focuses on maximum-mobility and minimum-energy opportunities associated with emerging transportation and transportation-related technologies specifically within the urban context. Such technologies, often referred to as automated, connected, efficient (or electrified), and shared (ACES), have the potential to greatly improve mobility and related quality of life in urban areas. Although all the SMART Mobility research pillars share some commonalities, Urban Science strives to model, analyze, and gain insights from the perspective of human settlements (the “city”) as a living organism. This is especially critical as the United States is one of the most urbanized countries, and as more and more of the global population migrates to urban areas.1 The urban mobility system consists of a complex network that reaches well beyond roads and vehicles and includes significant investments in public transit, private mobility services (such as taxis and transportation network companies, or TNCs), significant parking reserves, and curb management practices, not to mention the abundance of emerging on-demand micromobility services for the movement of people and goods such as e-bikes and scooters, which make the urban space a dynamic laboratory for mobility. Urban spaces also concentrate employment, markets, services, and attractions, which are the destinations for most trips. The concentration of human activities and ensuing density also creates the need and emphasis for space efficiency in urban environments, which is often less of a constraint in suburban or rural contexts. This mixture of transportation and mobility infrastructure and practice, combined with global urbanization trends, make urban spaces a critical focus of research for developing energy-efficient mobility systems (EEMS).

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2020

Geophysical and Planetary Acoustics on Balloons

Natural events and human activity often generate acoustic waves capable of traveling tens to tens of thousands of kilometers across the globe. Ground-based acoustic sensors are limited to dry land and often suffer from wind noise. In contrast, balloon borne acoustic sensors can cross oceans, polar ice caps, and other inhospitable areas, greatly expanding sensor coverage. Since they move with the mean wind speed, their background noise levels are exceptionally low. In the last six years, such sensors have recorded sounds from colliding ocean waves, surface and buried chemical explosions, thunder, wind/mountain interactions, wind turbines, aircraft, and possibly meteors and the aurora. These results have led to new insights on acoustic heating of the upper atmosphere, the detectability of underground explosions, and directional sound fields generated by ocean waves.

47 OTHER INSTRUMENTATION↗
DOE OSTI2020

Fire, dust, air and water: Improving aerosol biogeochemistry interactions in ACME. Final report

Aerosol-biogeochemistry interactions will have important consequences for human health, ecosystem services, and climate feedbacks over the next several decades. In this proposal we seek to link how human activities on land, including direct industrial emissions and landscape fires, impact the atmosphere and the biogeochemistry of the ocean and land. Our overall goal was to complement existing work at DOE labs to improve the capability and performance of the E3SM model in short-term, high-resolution projections of climate. Projections of ocean uptake of anthropogenic carbon are highly dependent on the details of the ocean physical and biogeochemistry parameterizations. Potentially equally important are the estimates of increases in iron and soluble nitrogen deposition in aerosols to the open ocean, but there are substantial uncertainties in these feedbacks. The E3SM land model simulates natural and anthropogenic fires, but improvement is needed to more accurately simulate fire responses to climate variability as well as fire contributions to terrestrial climate feedbacks. This proposal addressed four of the six priorities within the ACME/E3SM call by improving the representation of fire, industrial combustion sources, and desert dust and adding iron and soluble iron to the atmospheric chemistry (1). Our work focused on improving ocean biogeochemistry and the response of the oceans to anthropogenic atmospheric iron and nitrogen (3). We also improved the representation of land disturbance on fires and fire mediated carbon cycle feedbacks in the land model (4). Finally we had planned to couple the land, atmosphere and ocean biogeochemical systems (6) and explore how this coupling changes the feedbacks in the climate system. Our work under this proposal was separated into the following 5 tasks: i) improve representation of fire dynamics in both boreal and tropical ecosystems, ii) improve estimates of industrial emissions of iron and phosphorus, iii) improve representation of atmospheric iron, phosphorus and nitrogen transport, chemistry and deposition, iv) improve representation of iron, phosphorus and nitrogen deposition impacts on ocean biogeochemistry, and v) couple emissions into atmosphere, to deposition onto land and ocean biogeochemistry. For all 5 tasks, we conducted offline experiments of the historical period to enable comparison with available aerosol and land surface observations. We had planned to conduct fully coupled simulations, however, these will be conducted as part of the coupling in version 3 and 4 of the E3SM model, and thus have not been completed.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2021

A Modular System for Increasing Predictiveness for Extreme Climate Predictions

We know that climate change is poised to reshape our world, but we lack clear enough predictions about precisely how. The preponderance of these changes is associated with human activity, specifically the emission of CO 2 and other greenhouse gases. Problematically, projections of climate change continue to be marred by unacceptably large uncertainties which hamper informed decision-making and cost society a chance to adapt proactively and effectively. These uncertainties stem from deficiencies in predictions of future greenhouse gas emissions, but also from inaccuracies in the representation of the physical models used to predict the climate response to such emissions. The uncertainties in projections associated with the inaccurate representation of climate physics, chemistry and biology are similar to those that plagued the first global climate models developed fifty years ago, despite more than a factor 10 8 increase in computer performance. Our transformational question is then, how can the accuracy of climate projections be dramatically improved by applying recent advances in the computational and data sciences to train the models with the wealth of data being constantly collected about the ongoing changes in the climate system?

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2021

Bridging Multiscale Processes in Earth System Models with Physics-Guided Hierarchical Machine Learning

Focal Area(s): The focal area of this whitepaper is, “Predictive modeling through the use of AI techniques and AI-derived model components; the use of AI and other tools to design a prediction system comprising of a hierarchy of models (e.g., AI driven model/component/parameterization selection).” The ideas and frameworks described herein are deemed site agnostic. As a use case, this group will initially focus on the coupling between land processes, surface/subsurface hydrological processes, coastal processes, and human activities in the U.S. Gulf states.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

Methane Remediation using Biocatalysts in Gas-Solid Reactor – Challenges and Prospects

One of the engineering grand challenges of the 21 st century is to develop carbon sequestration methods due to human activities. Carbon dioxide and methane are the two most abundant greenhouse gases with methane having a higher global warming potential (GWP) than carbon dioxide. Methanotrophs are a time of bacteria that consumes methane and can produce different kinds of organic acids. Wild methanotrophs produce a range of products and can be specifically selected and genetically engineered to produce a specific product. Improvement of bioreactor design for a solid-gas mass transfer is necessary for this technology to move forward. Poor solubility of methane requires high energy input for the conversion of methane. This paper reviews some relevant technology in bioreactor design of gas and liquid/solid interfaces and describes the scope of the project here at LLNL and the objectives it seeks to achieve in the geometric design of reactor of methanotroph.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Gaussian Process Emulators for Volcanic Ash Dispersion Model Tephra2

It is necessary to predict volcanic ash deposition since falling ash is harmful to human activities. Because simulators built for this purpose are computationally expensive, it is popular to use statistical emulators for geophysical hazard analyses, where a large number of simulations are required. Gaussian stochastic process emulators are able to approximate expensive simulations in an accurate and efficient way. Using a relatively small number of simulation runs, a well-trained emulator can accurately predict simulation outputs at massive new input points in a few seconds. Under different explosive eruption conditions, we constructed Gaussian stochastic process emulators for Tephra2, a simulation tool for estimating the accumulation of volcanic ash over a region. Historical wind records are used as input wind data, without assuming a Gaussian wind speed profile or common wind direction among elevations. While there are several inputs for Tephra2, we use no more than three physically motivated variables as emulator inputs to reduce the computational cost of emulations. The emulator outputs predict the mass of tephra per unit area at 50281 grid points around a predetermined vent location.

58 GEOSCIENCES↗
DOE OSTI2022

Cloud And Precipitation Experiment at Kennaook

The remote Southern Ocean is an area of great interest to atmospheric scientists because of its influence on global atmospheric and oceanic circulation. With less influence from aerosols produced by human activities than most areas on Earth, the region provides a view into preindustrial conditions. Climate projections for the entire Earth are sensitive to the aerosol-cloud-precipitation interactions in the Southern Ocean atmosphere. This is particularly true of the ubiquitous low-level clouds that control the amount of sunlight absorbed at the ocean surface. Satellite data suggest that cloud properties co-vary with the seasonal cycle of aerosols in the region. Seasonal variations in Southern Ocean aerosol properties are strong and well documented, but detailed vertically resolved measurements of clouds and precipitation in the marine boundary layer are lacking. To help fill this gap, the Atmospheric Radiation Measurement (ARM) user facility will deploy a set of instruments for the Cloud And Precipitation Experiment at Kennaook (CAPE-K) from April 2024 to September 2025 in northwestern Tasmania.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

Simulating Extreme Precipitation in the United States in the Energy Exascale Earth System Model: Investigating the Importance of Representing Convective Intensity versus Dynamic Structure (Final Report)

Weather events that produce extreme precipitation are associated with severe flooding and winds that result in thousands of deaths and billions of dollars in damages annually in the United States (U.S.). This project aims to improve understanding of the small- and large-scale processes that govern these events and improve our ability to project changes in these extreme events under the influences of natural variability and human activities. We focus on two promising directions in the development of the U.S. Department of Energy’s Energy Exascale Earth System Model (E3SM) to investigate the tradeoffs between resolving the convective-scale processes that control the intensity versus the intermediate-scale processes that control the dynamic structure of the most prominent extreme precipitation events that impact the U.S. throughout the year (i.e., mesoscale convective systems, tropical cyclones, and extratropical cyclone).

58 GEOSCIENCES↗
DOE OSTI2023

Greenhouse Gases Observations 1957-2100: Past, Present & Future

Dr. David Charles Keeling’s precise CO 2 observations at the remote Mauna Loa site discerned its global rise that is attributed to emissions from human activities. His Keeling curve is the observational framework to examine anthropogenic climate change that has expanded to other greenhouse gases (GHGs) and monitoring techniques. The accelerating GHG rise and the heat absorbed by them led to concerns about climate change that have exacerbated.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2023

Thermodynamics of Minerals Stable near Earth's Surface

Project “Thermodynamics of Minerals Stable Near the Earth’s Surface” uses specialized calorimetric techniques to obtain new thermochemical data for solid phases of interest in the Earth’s “critical zone”, the near surface regions of the planet most directly affecting and affected by human activity. Major activity was in three areas: manganese oxide materials, aluminum clusters which are precursors to aluminum oxyhydroxide precipitates, and zeolites. All these classes of minerals are potential carriers of heavy metals and radionuclides in the environment, both within their crystal structures and as adsorbed layers or colloids. Their thermodynamic stability, as well as the sequence of stability of competing phases, governs the aqueous solubility of contaminants (and nutrients) in soil, groundwater, and sediments. The thermodynamics of these phases is strongly affected by particle size and crystallinity, since they often occur as very fine particles which do not coarsen in the near-surface environment. Many of these materials exhibit extensive polymorphism, multicomponent solid solution, and variable hydration states. Thus, one must define and systematize important thermodynamic variables, since one cannot make measurements on each and every possible phase, particle size, and composition. A major finding of the work on manganese oxides was labile water-induced oxidation-reduction reactions. These will be studied further by a combination of thermodynamic and synchrotron-based spectroscopic methods, the latter in collaboration with Peggy O’Day at UC Merced. The adsorption of other species, including simple organics, on such redox-active surfaces will also be investigated by a combination of thermochemical and spectroscopic studies. Studies of the energetics of water adsorption on mineral surfaces will be expanded to emphasize the adsorption of CO2 and small organic molecules, relevant to soil, groundwater, and the subsurface environment. Gas adsorption calorimetry, immersion calorimetry, and solution calorimetry will be combined with appropriate analytical and spectroscopic techniques to obtain a comprehensive picture of the interactions and their energetics. The evolution of aqueous aluminum clusters to form aluminum oxyhydroxide precipitates will be studied in detail by a combination of calorimetric and structural methods applied to aqueous samples aged at room temperature. The energetics of new classes of clusters will be explored. The project addresses several common themes relevant to the broad mission of the Department of Energy. Thermochemical data for minerals stable near the Earth’s surface, though still incomplete, are essential for understanding both natural and anthropogenic processes that affect our very existence on this planet. Such data contribute to the fundamental underpinning for mitigation and management strategies for the extraction and use of energy. Fundamental thermodynamic and mechanistic understanding is required to model processes ranging from heavy metal pollution to nuclear waste disposal to climate change.

58 GEOSCIENCES↗
DOE OSTI2024

NSA Site Science: Use of ARM Observations from Northern Alaska to Evaluate and Improve Prediction Capabilities

The Arctic is warming at a rate nearly double that of the rest of the planet, leading to profound changes in atmospheric, oceanic, and ice processes. The U.S. Department of Energy's (DOE) Atmospheric Radiation Measurement (ARM) user facility has played a significant role in Arctic research, operating observatories in Alaska's North Slope for over 25 years. These observatories provide a rich, and wide-reaching dataset that offers insight into atmospheric processes in northern Alaska. This report details the results of a nine-year research project (2015–2024) supported by the DOE Atmospheric Systems Research (ASR) program, that leverages data from ARM’s deployment of observing facilities at Utqiaġvik (known as the North Slope of Alaska, or NSA, site) and Oliktok Point, Alaska. The project was conducted in two phases: - Phase 1 (2015–2019): Focused on understanding key atmospheric processes at Oliktok Point, including cloud formation, high-latitude precipitation, aerosol-cloud interactions, and cloud properties. - Phase 2 (2019–2024): Extended the research to the broader North Slope region, using data from both Oliktok Point and Utqiaġvik. Topics explored included surface energy budgets, atmospheric stability, ice nucleation processes, and microphysics in Arctic clouds. The project resulted in numerous research products, including 50 peer-reviewed publications and dissertations, 169 presentations, and 10 data products. These products cover a variety of topics, including: - Cloud Macro- and Microphysical Properties: Arctic clouds play a crucial role in energy transfer, and accurate representation in models is critical. The study explored cloud transitions, ice crystal shapes, and dual-wavelength radar data to understand ice crystal habits and size distributions. - Aerosol Properties and Processes: The team examined aerosol sources in the Arctic, including industrial emissions and natural sources. Observations showed significant spatial gradients in aerosol concentrations due to human activities and wildfire smoke. The influence of aerosols on cloud formation and the surface energy budget was also assessed. - Aerosol-Cloud Interactions: Research revealed that aerosols might suppress cloud ice production, affecting cloud radiative forcing and precipitation. The impact of local industrial emissions on cloud properties was also investigated. - Contextualizing the North Slope of Alaska in the context of the broader Arctic: To understand broader trends, the project evaluated large-scale circulation patterns and the influence of weather systems on the Arctic. Studies indicated that large-scale processes play a significant role in temperature patterns and the timing of snowmelt. - Advancing ARM Observational and Modeling Capabilities: The project developed new radar data products and advanced measurement techniques, including clutter mitigation and drizzle detection. Uncrewed aerial systems (UAS) and tethered balloon systems (TBS) were deployed to gather detailed atmospheric data. Additionally, the project supported 10 early career scientists, providing training and mentorship to undergraduate interns, graduate students, postdoctoral researchers, and early career researchers. These efforts contributed to the advancement of ARM research capabilities and fostered a new generation of scientists skilled in Arctic atmospheric research. Ultimately, this ASR-supported project has provided valuable insights into Arctic atmospheric processes and their broader climate implications. Recommendations for future work include continuing support for long-term observing at Arctic locations to foster additional research, further exploration of aerosol-cloud interactions and the potential impacts of enhanced industrialization of the Arctic, and expanded use of uncrewed systems to gather data in this remote and harsh environment. Additionally, the data products developed by this work, and the data products developed through the ARM infrastructure, leave a treasure-trove of additional information that should be explored for many years to come to gain additional insight into physical processes in the Arctic atmosphere that drive the rapid changes occurring in at high latitudes and their global impact.

58 GEOSCIENCES↗
DOE OSTI2024

Modification of CO2/H2O Selectivity of Polymer Through Graphene Coating for Carbon Capture Materials

A harmful issue that needs attention and solution is the rising carbon dioxide (CO2) in our atmosphere. Carbon dioxide in our atmosphere is at an all time high and has continuously increased since the industrial revolution. It has increased tremendously going from 315 parts per million (ppm) in the 1960s up to 419.3 ppm in 2023 as shown in Figure 1. Moreover, CO2 emissions have increased from 11 billion tons/year in the 1960s to 38.6 billion tons/year in 2023. The increase in CO2 found in our atmosphere has a number of detrimental effects such as increase in global temperatures and an increase in the ocean’s acidity. Human activities are greatly involved in the cause of CO2 emissions. At Lawrence Livermore National Lab (LLNL) the Microencapsulated CO2 sorbents (MECS) division has been doing research and investigating formulations for their microcapsules. MECS are core-shell microcapsules consisted of a highly permeable polymer shell and a fluid (sodium carbonate solution) that reacts and absorbs carbon dioxide. An example of the microcapsules are shown in Figure 2. Equation 1 shows the chemical reaction of the fluid (sodium carbonate) contained in the polymer shell that acts as the carbon dioxide sorbent and becomes sodium bicarbonate. The LLNL MECS team is in the process of scaling up their microcapsules for potential applications in “carbon capture from flue gas streams generated by fossil fuel combustion in industrial plants and operations, carbon capture in breweries and soft drink manufacture, carbon capture directly from indoor air to improve its quality”. The microcapsule’s possibility for commercial applications was discovered in 2017.

36 MATERIALS SCIENCE↗
DOE OSTI2023

Chemical controls on the propagation and healing of subcritical fractures

Human activities involving subsurface reservoirs—resource extraction, carbon and nuclear waste storage—alter thermal, mechanical, and chemical steady-state conditions in these systems. Because these systems exist at lithostatic pressures, even minor chemical changes can cause chemically assisted deformation. Therefore, understanding how chemical effects control geomechanical properties is critical to optimizing engineering activities. The grand challenge in predicting the effect of chemical processes on mechanical properties lays in the fact that these phenomena take place at molecular scales, while they manifest all the way to reservoir scales. To address this fundamental challenge, we investigated chemical effects on deformation in model and real systems spanning molecular- to centimeter scales. We used theory, experiment, molecular dynamics simulation, and statistical analysis to (1) identify the effect of simple reactions, such as hydrolysis, on molecular structures in interfacial regions of stressed geomaterials; (2) quantify chemical effects on the bulk mechanical properties, fracture and displacement for granular rocks and single crystals; (3) develop initial understanding of universal scaling for individual displacement events in layered geomaterials; and (4) develop analytic approximations for the single-chain mechanical response utilizing asymptotically correct statistical thermodynamic theory. Taken together, these findings advance the challenging field of chemo-mechanics.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Improving North American Wildfire Prediction by Integrating a Machine-Learning Fire Model in a Land Surface Model

Wildfires have shown increasing trends in both frequency and severity across the Contiguous United States (CONUS). However, process-based fire models have difficulties in accurately simulating the burned area over the CONUS due to a simplification of the physical process and cannot capture the interplay among fire, ignition, climate, and human activities. The deficiency of burned area simulation deteriorates the description of fire impact on energy balance, water budget, and carbon fluxes in the Earth System Models (ESMs). Alternatively, machine learning (ML) based fire models, which capture statistical relationships between the burned area and environmental factors, have shown promising burned area predictions and corresponding fire impact simulation. We develop a hybrid framework (ML4Fire-XGB) that integrates a pretrained eXtreme Gradient Boosting (XGBoost) wildfire model with the Energy Exascale Earth System Model (E3SM) land model (ELM) version 2.1. A Fortran-C-Python deep learning bridge is adapted to support online communication between ELM and the ML fire model. Specifically, the burned area predicted by the ML-based wildfire model is directly passed to ELM to adjust the carbon pool and vegetation dynamics after disturbance, which are then used as predictors in the ML-based fire model in the next time step. Evaluated against the historical burned area from Global Fire Emissions Database 5 from 2001-2020, the ML4Fire-XGB model outperforms process-based fire models in terms of spatial distribution and seasonal variations. Sensitivity analysis confirms that the ML4Fire-XGB well captures the responses of the burned area to rising temperatures. The ML4Fire-XGB model has proved to be a new tool for studying vegetation-fire interactions, and more importantly, enables seamless exploration of climate-fire feedback, working as an active component in E3SM.

54 ENVIRONMENTAL SCIENCES↗