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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 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Challenges of open data in aquatic sciences: issues faced by data users and data providers

Free use and redistribution of data (i.e., Open Data) increases the reproducibility, transparency, and pace of aquatic sciences research. However, barriers to both data users and data providers may limit the adoption of Open Data practices. Here, we describe common Open Data challenges faced by data users and data providers within the aquatic sciences community (i.e., oceanography, limnology, hydrology, and others). These challenges were synthesized from literature, authors’ experiences, and a broad survey of 174 data users and data providers across academia, government agencies, industry, and other sectors. Through this work, we identified seven main challenges: 1) metadata shortcomings, 2) variable data quality and reusability, 3) open data inaccessibility, 4) lack of standardization, 5) authorship and acknowledgement issues 6) lack of funding, and 7) unequal barriers around the globe. Our key recommendation is to improve resources to advance Open Data practices. This includes dedicated funds for capacity building, hiring and maintaining of skilled personnel, and robust digital infrastructures for preparation, storage, and long-term maintenance of Open Data. Further, to incentivize data sharing we reinforce the need for standardized best practices to handle data acknowledgement and citations for both data users and data providers. We also highlight and discuss regional disparities in resources and research practices within a global perspective.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2020

Simulator for Hydrologic Unstructured Domains (SHUD v1.0): numerical modeling of watershed hydrology with the finite volume method

Abstract. Hydrologic modeling is an essential strategy for understanding and predicting natural flows, particularly where observations are lacking in either space or time or where complex terrain leads to a disconnect in the characteristic time and space scales of overland and groundwater flow. However, significant difficulties remain for the development of efficient and extensible modeling systems that operate robustly across complex regions. This paper introduces the Simulator for Hydrologic Unstructured Domains (SHUD), an integrated, multiprocess, multiscale, flexible-time-step model, in which hydrologic processes are fully coupled using the finite volume method. SHUD integrates overland flow, snow accumulation/melt, evapotranspiration, subsurface flow, groundwater flow, and river routing, thus allowing physical processes in general watersheds to be realistically captured. SHUD incorporates one-dimensional unsaturated flow, two-dimensional groundwater flow, and a fully connected river channel network with hillslopes supporting overland flow and baseflow. The paper introduces the design of SHUD, from the conceptual and mathematical description of hydrologic processes in a watershed to the model's computational structures. To demonstrate and validate the model performance, we employ three hydrologic experiments: the V-catchment experiment, Vauclin's experiment, and a model study of the Cache Creek Watershed in northern California. Ongoing applications of the SHUD model include hydrologic analyses of hillslope to regional scales (1 m2 to 106 km2), water resource and stormwater management, and interdisciplinary research for questions in limnology, agriculture, geochemistry, geomorphology, water quality, ecology, climate and land-use change. The strength of SHUD is its flexibility as a scientific and resource evaluation tool where modeling and simulation are required.

58 GEOSCIENCES↗
DOE OSTI2026

The Zooplankton International Geospatial (ZIG) dataset: A global repository of spatiotemporal freshwater zooplankton community composition data to support ecological research

Zooplankton play critical roles in aquatic ecosystem function and food webs. Nevertheless, global syntheses of their abundance and community dynamics are challenging due to methodological differences across monitoring programs, taxonomic inconsistencies, and a lack of standardized metadata. To reconcile these challenges, we assembled, curated, validated, and harmonized the Zooplankton International Geospatial (ZIG) dataset, which includes co-located and contemporaneous zooplankton, water chemistry, and limnological data from 307 lakes and reservoirs. ZIG includes waterbodies from each major lake thermal region and range in size from 0.8-2,805,8600 hectares. Temporal coverage for individual waterbodies ranges between 1-60 years of data (median = 4 years) with sampling from once annually to weekly. ZIG is publicly available and can be used to understand freshwater biodiversity change and its drivers at unprecedented scales, and we consider it to be a cornerstone for future investigations of freshwater biology, chemistry, and ecology.

Figary, Stephanie [Cornell University, Ithaca, NY]↗
NASA NTRS1972

Pollution detection in Lake Champlain using ERTS-1 imagery

The author has identified the following significant results. A major waste water discharge plume generated by a large paper mill along the New York shore of Lake Champlain was visually detected on ERTS-1 imagery. The plume is best displayed in 9.5 inch positive transparencies of MSS bands 4 and 5. Observation of the magnitude and extent of this plume is feasible, under magnification of 4 times. The chemical parameters of this plume have been documented by limnological studies. An enhancement technique useful for documenting the presence of waste water discharge plumes in Lake Champlain utilizes Polaroid MP-3 copy camera equipment and Spectral Data Corporation's multispectral viewer. The 9.5 inch, ERTS-1, positive transparency is enlarged using the Polaroid MP-3 copy camera to produce an enlarged lantern slide size positive transparency. These are projected through the multispectral viewer for enhancement and the scene is viewed directly on the screen or copied by an additional photographic step. The technique is simple and produces rapid results.

Lind, A. O.↗
NASA NTRS1972

Progress and plans of a remote sensing program for the International Field Year for the Great Lakes (IFYGL)

The author has identified the following significant results. ERTS-1 coverage of the 32,000 square mile Lake Ontario Basin is being used to study short term and seasonal changes which affect many aspects of water problems in the Great Lakes. As part of the International Field Year for the Great Lakes (IFYGL), a coordinated, synoptic study of the Lake Ontario Basin, processed ERTS-1 imagery will contribute to the data base of synchronized observations being made by investigators from many U.S. and Canadian government agencies and universities. The first set of ERTS data has been received and will be processed shortly for parameters of hydrological and limnological significance such as land use, terrain features, and water quality. When complete, nine ERTS-1 frames recorded during a substantially clear period will provide coverage of the entire Basin. Seven frames show all but a small portion of the southern and eastern end of the Basin. Many drainage basin characteristics are clearly identifiable on the imagery.

Polcyn, F. C.↗
NASA NTRS1974

Application of ERTS imagery to environmental studies of Lake Champlain

ERTS Imagery has provided data relating to a number of environmental and limnological concerns such as water quality, lake flooding and lake ice formation. Pollution plume data provided by ERTS was recently used in the Supreme Court case involving the States of Vermont and New York and a paper company. Flooding of lowland tracts has been a major concern due to a repetitive pattern of high lake levels over the past three years, and ERTS imagery is being used to construct the first series of flood maps of the affected areas. Lake ice development and turbidity patterns have also been studied from ERTS, since these have significance for shore erosion studies.

Lind, A. O.↗
NASA NTRS1974

Remote sensing and lake eutrophication

An infrared photograph of part of Clear Lake, Cal., shows complex patterns of blue-green algal blooms which were not observed by conventional limnological techniques. Repeated observations of patterns such as these can be used to chart the surface movement of these buoyant algae and can also be used to help control algal scums in eutrophic lakes. Although it is believed that most of the observed patterns resulted from Aphanizomenon (a few were also observed which resulted from suspended sediment), spectral signatures of the algal patterns varied.

Wrigley, R. C.↗
NASA NTRS1975

An ERTS-1 investigation for Lake Ontario and its basin

The author has identified the following significant results. Methods of manual, semi-automatic, and automatic (computer) data processing were evaluated, as were the requirements for spatial physiographic and limnological information. The coupling of specially processed ERTS data with simulation models of the watershed precipitation/runoff process provides potential for water resources management. Optimal and full use of the data requires a mix of data processing and analysis techniques, including single band editing, two band ratios, and multiband combinations. A combination of maximum likelihood ratio and near-IR/red band ratio processing was found to be particularly useful.

Polcyn, F. C.↗
NASA NTRS1977

Earth resources-regional transfer activity contracts review

A regional transfer activity contracts review held by the Earth Resources Office was summarized. Contracts in the earth resources field primarily directed toward applications of satellite data and technology in solution of state and regional problems were reviewed. A summary of the progress of each contract was given in order to share experiences of researchers across a seven state region. The region included Missouri, Kentucky, Tennessee, Mississippi, Alabama, Georgia, and North Carolina. Research in several earth science disciplines included forestry, limnology, water resources, land use, geology, and mathematical modeling. The use of computers for establishment of information retrieval systems was also emphasized.

Bensko, J., Jr.↗
NASA NTRS1980

Life from a plantary perspective: Fundamental issues in global ecology

Twenty-three scientists from diverse disciplines met for one week at the University of California, Santa Barbara to discuss life from a planetary perspective. The scientists represented the major disciplines concerned with the Earth's biota, oceans, atmosphere and sediments, including geochemistry, atmospheric chemistry, chemical oceanography, limnology, forestry, terrestrial ecology, microbiology, biophysics, geography and remote sensing as well as mathematics. These twenty-three scientists met to discuss whether there was, at this time, a set of scientific issues concerning life and the entire Earth as a single unit, to set down the major tractable issues, and to suggest a set of activities that would promote the study of the issues identified. Their conclusions are summarized.

Botkin, D. B.↗
NASA NTRS1980

Thermal Pollution Mathematical Model: Verification of One-Dimensional Numerical Model at Lake Keowee - Volume 2

A one dimensional model for studying the thermal dynamics of cooling lakes was developed and verified. The model is essentially a set of partial differential equations which are solved by finite difference methods. The model includes the effects of variation of area with depth, surface heating due to solar radiation absorbed at the upper layer, and internal heating due to the transmission of solar radiation to the sub-surface layers. The exchange of mechanical energy between the lake and the atmosphere is included through the coupling of thermal diffusivity and wind speed. The effects of discharge and intake by power plants are also included. The numerical model was calibrated by applying it to Cayuga Lake. The model was then verified through a long term simulation using Lake Keowee data base. The comparison between measured and predicted vertical temperature profiles for the nine years is good. The physical limnology of Lake Keowee is presented through a set of graphical representations of the measured data base.

Lee, S. S.↗
NASA NTRS1987

The effect of wind and currents on gas exchange in an estuarine system

The objectives were to develop a non-volatile tracer to use in gas exchange experiments in laterally unconfined systems and to study applications of deliberate tracers in limnology and oceanography. Progress was made on both fronts but work on the development of the non-volatile tracer proved to be more difficult and labor intensive that anticipated so no field experiments using non-volatile tracers was performed as yet. In the search for a suitable non-volatile tracer for an ocean scale gas exchange experiment a tracer was discovered which does not have the required sensitivity for a large scale experiment, but is very easy to analyze and will be well suited for smaller experiments such as gas exchange determinations on rivers and streams. Sulfur hexafluoride, SF6, was used successfully as a volatile tracer along with tritium as a non-volatile tracer to study gas exchange rates from a primary stream. This is the first gas exchange experiment in which gas exchange rates were determined on a head water stream where significant groundwater input occurs along the reach. In conjunction with SF6, Radon-222 measurements were performed on the groundwater and in the stream. The feasibility of using a combination of SF6 and radon is being studied to determine groundwater inputs and gas exchange of rates in streams with significant groundwater input without using a non-volatile tracer.

Broecker, W. S.↗
NASA NTRS1990

The biogeochemistry of metal cycling

The results of the Planetary Biology and Microbial Ecology's summer 1987 program are summarized. The purpose of the interdisciplinary PBME program is to integrate, via lectures and laboratory work, the contributions of university and NASA scientists and student interns. The 1987 program examined various aspects of the biogeochemistry of metal cycling, and included such areas as limnology, metal chemistry, metal geochemistry, microbial ecology, and interactions with metals. A particular area of focus was the use of remote sensing in the study of biogeochemistry. Abstracts and bibliographies of the lectures and reports of the laboratory projects are presented.

Nealson, Kenneth H.↗
NASA NTRS1995

AVIRIS user's guide

This paper serves as a brief overview of the AVIRIS instrument (Airborne Visible/Infrared Imaging Spectrometer). The AVIRIS sensor collects data that will be used for quantitative characterization of the Earth's surface and atmosphere from geometrically coherent spectroradiometric measurements. This data can be applied to studies in the fields of oceanography, environmental science, snow hydrology, geology, volcanology, soil and land management, atmospheric and aerosol studies, agriculture, and limnology. Applications under development include the assessment and monitoring of environmental hazards such as toxic waste, oil spills, and land/air/water pollution. Mission planning and flight operations are discussed, and recommendations are given regarding the deployment of ground truth experiments.

Johnson, Howell K.↗
NASA NTRS1995

Paleolakes on Mars

Observational evidence such as outflow channels and valley networks suggest that in the past there was flowing water on Mars. The images of fluvial features on Mars logically suggest that there must exist downstream locations in which the water pooled and the sediment load deposited (i.e. lakes). Sediments and morphological features associated with the martian paleolakes are believed to occur in Valles Marineris, and several large basins including Amazonis, Chryse and Elysium planitia. As Mars became progressively colder over geological time, any lakes on its surface would have become seasonally, and eventually perennially ice-covered. We know from polar lakes on Earth that ice-covered lakes can persist even when the mean annual temperature falls below freezing. Thus, the most recent lacustrine sediments on Mars were probably deposited in ice-covered lakes. While life outside of the Earth's atmosphere has yet to be observed, there is a general consensus among exobiologists that the search for extraterrestrial life should be based upon liquid water. The inference that there was liquid water on Mars during an earlier epoch is the primary motivation for considering the possibility of life during this time. It would be of enormous interest from both an exobiological and paleolimnological perspective to discover lakes or the evidence of former lakes on another planet such as Mars. Limnology would then become an interplanetary science.

NASA Center ARC↗
NASA NTRS2009

The Open Source DataTurbine Initiative: Streaming Data Middleware for Environmental Observing Systems

The Open Source DataTurbine Initiative is an international community of scientists and engineers sharing a common interest in real-time streaming data middleware and applications. The technology base of the OSDT Initiative is the DataTurbine open source middleware. Key applications of DataTurbine include coral reef monitoring, lake monitoring and limnology, biodiversity and animal tracking, structural health monitoring and earthquake engineering, airborne environmental monitoring, and environmental sustainability. DataTurbine software emerged as a commercial product in the 1990 s from collaborations between NASA and private industry. In October 2007, a grant from the USA National Science Foundation (NSF) Office of Cyberinfrastructure allowed us to transition DataTurbine from a proprietary software product into an open source software initiative. This paper describes the DataTurbine software and highlights key applications in environmental monitoring.

Fountain T.↗
NASA NTRS2020

Satellite and airborne remote sensing of gross primary productivity in boreal Alaskan lakes

In terrestrial and marine ecosystems, remote sensing has been used to estimate gross primary productivity (GPP) for decades, but few applications exist for shallow freshwater ecosystems.Here we show field-based GPP correlates with satellite and airborne lake color across a range of optically and limnologically diverse lakes in interior Alaska. A strong relationship between in situ GPP derived from stable oxygen isotopes (δ18O) and space-based lake color from satellites (e.g. Landsat-8, Sentinel-2 and CubeSats) and airborne imagery (AVIRIS-NG) demonstrates the potential power of this technique for improving spatial and temporal monitoring of lake GPP when coupled with additional field validation measurements across different systems. In shallow waters clear enough for sunlight to reach lake bottoms, both submerged vegetation (macrophytes and algae) and phytoplankton likely contribute to GPP. The stable isotopes and remotely sensed shallow lake color used here integrate both components. These results demonstrate the utility of lake color as a feasible means for mapping lake GPP from remote sensing. This novel methodology estimates GPP from remote sensing in shallow lakes by combining field measurements of oxygen isotopes with airborne, satellite and CubeSat imagery. This use of lake color for providing insight into ecological processes of shallow lakes is recommended, especially for remote arctic and boreal landscapes.

airborne remote sensing↗