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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 109 records · Page 6
All sourcesNASA NTRSDOE OSTI
NASA NTRS1973

Derivation of a three dimensional numerical water quality model for estuary and continental shelf application

A derivation is given for a three dimensional mass transport equation which is appropriate for numerical modeling of estuary and continental shelf water quality variations for both the time dependent and steady state cases. A finite difference approximation to the derived equation is presented and a solution scheme for the resulting equations outlined. Preliminary results are obtained using the model for the extremely simple problems which have analytical solutions. The numerical model, as presented, will provide a scheme to study water quality problems in coastal waters for both steady state and time dependent cases.

Spaulding, M.↗
NASA NTRSDate not supplied

A Lunar Water ISRU System Study for Human-Scale Propellant Production

NASA’s plans to return to the moon in the Artemis campaign include intentions for sustainable surface operations. In-Situ Resource Utilization (ISRU) is key to enabling sustainability. The use of water, which has been identified in the lunar polar regions [1-4], could be pivotal to a sustainable architecture. While water has been identified, there is limited information regarding its form and distribution. The Lunar Water ISRU Measurement Study (LWIMS) [5] outlined the current state of knowledge regarding water resources on the moon, what information is lacking, and how to approach a measurement campaign to close those knowledge gaps. However the NASA timeline necessitates that lunar surface water prospecting, or reconnaissance, efforts and ISRU system design to occur in parallel. ISRU hardware and systems development must proceed without key resource knowledge. Yet, engineering design requires come constraints and targets to work to. The goal of this study was to define a set of lunar water reference cases, based on the cur-rent lunar water information, to help focus ISRU de-sign and planning. This approach is similar to an study focused on Mars resources called Mars Water ISRU Planning (MWIP) [6].

Lunar Water↗
NASA NTRS1972

Mars - Are observed white clouds composed of H2O.

A total of 252 occurrences of white clouds are studied. Water abundances are compared with those of white clouds as a function of latitude on Mars. It appears not necessarily to be the case that observed cloud frequencies will always follow water abundances. Martian white cloud frequencies tend to follow the distribution of water both seasonally and latitudinally on the planet, which strongly suggests that most white clouds are formed from water vapor.

Wells, R. A.↗
NASA NTRS1974

Use of ERTS-1 data: Summary report of work on ten tasks

The author has identified the following significant results. Depth mapping's for a portion of Lake Michigan and at the Little Bahama Bank test site have been verified by use of navigation charts and on-site visits. A thirteen category recognition map of Yellowstone Park has been prepared. Model calculation of atmospheric effects for various altitudes have been prepared. Radar, SLAR, and ERTS-1 data for flooded areas of Monroe County, Michigan are being studied. Water bodies can be reliably recognized and mapped using maximum likelihood processing of ERTS-1 digital data. Wetland mapping has been accomplished by slicing of single band and/or ratio processing of two bands for a single observation date. Both analog and digital processing have been used to map the Lake Ontario basin using ERTS-1 data. Operating characteristic curves were developed for the proportion estimation algorithm to determine its performance in the measurement of surface water area. The signal in band MSS-5 was related to sediment content of waters by modelling approach and by relating surface measurements of water to processed ERTS data. Radiance anomalies in ERTS-1 data could be associated with the presence of oil on water in San Francisco Bay, but the anomalies were of the same order as those caused by variations in sediment concentration and tidal flushing.

Thomson, F. J.↗
NASA NTRS1981

Boundary detection criteria for satellite altimeters

A procedure for using satellite altimeter data to determine the time of crossing of a surface boundary, such as ocean land or ocean ice, with the primary objective to flag altimeter data that do not properly represent oceanographic measurements were studied. Water to land crossing and water to sea ice crossing were investigated. For ocean ice crossings, a large increase in AGC occurred. Waveform tests for increasing the probability of detecting an ocean land crossing were investigated. It is recommended that the boundary test be based on a fit of the full waveform to a limited parameter set at a rate of 5 to 10 second.

Martin, C. F.↗
NASA NTRS1982

Combining remotely sensed and other measurements for hydrologic areal averages

A method is described for combining measurements of hydrologic variables of various sampling geometries and measurement accuracies to produce an estimated mean areal value over a watershed and a measure of the accuracy of the mean areal value. The method provides a means to integrate measurements from conventional hydrological networks and remote sensing. The resulting areal averages can be used to enhance a wide variety of hydrological applications including basin modeling. The correlation area method assigns weights to each available measurement (point, line, or areal) based on the area of the basin most accurately represented by the measurement. The statistical characteristics of the accuracy of the various measurement technologies and of the random fields of the hydrologic variables used in the study (water equivalent of the snow cover and soil moisture) required to implement the method are discussed.

Johnson, E. R.↗
NASA NTRS1982

Significant results from the HCMM program

The major objectives of the HCMM program for applications in geology, agriculture, water studies, and the effects of climate on metropolitan areas are summarized. Results obtained by Principal Investigators in each of these disciplines are presented, discussed, and supported with figures and tables. In order to compare the types of observations and applications that can be derived from HCMM data with some remote sensing standard or framework for each discipline, the principal results already achieved with the LANDSAT system are included.

Source record↗
NASA NTRS2008

GEWEX Water and Energy Budget Study

Closing the global water and energy budgets has been an elusive Global Energy and Water-cycle Experiment (GEWEX) goal. It has been difficult to gather many of the needed global water and energy variables and processes, although, because of GEWEX, we now have globally gridded observational estimates for precipitation and radiation and many other relevant variables such as clouds and aerosols. Still, constrained models are required to fill in many of the process and variable gaps. At least there are now several atmospheric reanalyses ranging from the early National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) and NCEP/Department of Energy (DOE) reanalyses to the more recent ERA40 and JRA-25 reanalyses. Atmospheric constraints include requirements that the models state variables remain close to in situ observations or observed satellite radiances. This is usually done by making short-term forecasts from an analyzed initial state; these short-term forecasts provide the next guess, which is corrected by comparison to available observations. While this analysis procedure is likely to result in useful global descriptions of atmospheric temperature, wind and humidity, there is no guarantee that relevant hydroclimate processes like precipitation, which we can observe and evaluate, and evaporation over land, which we cannot, have similar verisimilitude. Alternatively, the Global Land Data Assimilation System (GLDAS), drives uncoupled land surface models with precipitation, surface solar radiation, and surface meteorology (from bias-corrected reanalyses during the study period) to simulate terrestrial states and surface fluxes. Further constraints are made when a tuned water balance model is used to characterize the global runoff observational estimates. We use this disparate mix of observational estimates, reanalyses, GLDAS and calibrated water balance simulations to try to characterize and close global and terrestrial atmospheric and surface water and energy budgets to within 10-20% for long term (1986-1995), large-scale global to regional annual means.

Roads, J.↗
NASA NTRS2017

Evolved-Lithology Clasts in Lunar Breccias: Relating Petrogenetic Diversity to Measured Water Content

Studies of the inventory and distribution of water in lunar rocks have recently begun to focus on alkali suite samples as possible water repositories, particularly the most highly evolved granitoid lithologies. Although H analyses of feldspars in these rocks have so far pointed to 'low' (less than 20 ppm) H2O contents, there is sufficient variability in the dataset (e.g., 2-20 ppm) to warrant consideration of the petrogenetic factors that may have caused some granitoid-to-intermediate rocks to be dryer or wetter than others. Given that all examples of these rocks occur as clasts in complex impact breccias, the role of impact and other factors in altering water contents established by primary igneous processes becomes a major factor. We are supporting our ongoing SIMS studies of water in evolved lunar lithologies with systematic SEM and EPMA observations. Here we report a synthesis of the observations as part of developing discriminating factors for reconstructing the thermal, crystallization and shock history of these samples as compared with their water contents.

Christoffersen, R.↗
NASA NTRS1991

Millimeter- and submillimeter-wave spectrum of highly excited states of water

To facilitate studies of water in the interstellar medium and late-type stars, the frequencies of 30 new millimeter- and submillimeter-wave transitions of H2O-16 have been measured, which lie between 100 GHz and 600 GHz. This represents almost a doubling of the number of water lines that have been observed in the laboratory in this spectral region at high resolution. All of the newly observed lines are highly excited, lying between 2400 and 4200/cm above the ground level. Some of these have large excitation energies because of their high rotational states and others because they lie in excited vibrational states. These lines are potentially of substantial astrophysical significance because they are related to the study of interstellar masers and because their high excitation eliminates the atmospheric self-absorption associated with the more well-known water lines.

Pearson, J. C.↗
NASA NTRS1984

Studies of Atmospheric Water in Storms with the Nimbus 7 Scanning Multichannel Microwave Radiometer

The new tools for the study of midlattitude cyclones by atmospheric water channels of the scanning multichannel microwave radiometer (SMMR) on Nimbus 7, were discussed. The integrated atmospheric water vapor, total cloud liquid water and rain data were obtained from the Nimbus 7 Scanning Multichannel Microwave Radiometer (SMMR). The frontal structure of several midlattitude cyclones over the North Pacific Ocean as they approached the West Coast of North America were studied. It is found that fronts are consistently located at the leading edge of the strongest gradient in integrated water vapor. The cloud liquid water content has patterns which are consistent with the structure seen in visible and infrared imagery. The rain distribution is a good indicator of frontal location. It is concluded that the onset of rain on the coast can be forecast accurately by simple advection of the SMMR observed rain areas.

Katsaros, K. B.↗
NASA NTRSDate not supplied

An Overview of the Lunar Water ISRU Measurement Study (LWIMS)

NASA announced plans for the Artemis program, which would send crewed missions to the Moon by 2024 and achieve a sustainable lunar presence by 2028 [1]. To carry out sustained crewed surface operations, In-Situ Resource Utilization (ISRU), which would use lunar resources to produce mission consumables, will be critical. Water-bearing materials have been identified at both lunar poles and are often associated with Permanently Shadowed Regions (PSRs). These constitute a geological resource that may or may not be convertible to reserves with additional exploration. This water could provide both fuel and oxygen for refueling vehicles as well as life support consumables. However, the nature and extent of this resource is not well understood. Detection of water alone is not adequate for ISRU planning. For this reason, NASA chartered the Lunar Water ISRU Measurement Study (LWIMS). The goal of this study was to assess and define the type, amount, and fidelity of the measurements needed to select mining locations for lunar water ISRU and to define resource-related requirements for ISRU hardware development and architectures (mining operations, hardware emplacement, concept of operations).

Julie Kleinhenz↗
NASA NTRS2017

Synthetic Scenarios from CMIP5 Model Simulations for Climate Change Impact Assessments in Managed Ecosystems and Water Resources: Case Study in South Asian Countries

Increasing population, urbanization, and associated demand for food production compounded by climate change and variability have important implications for the managed ecosystems and water resources of a region. This is particularly true for south Asia, which supports one quarter of the global population, half of whom live below the poverty line. This region is largely dependent on monsoon precipitation for water. Given the limited resources of the developing countries in this region, the objective of our study was to empirically explore climate change in south Asia up to the year 2099 using monthly simulations from 35 global climate models (GCMs) participating in the fifth phase of the Climate Model Inter-comparison Project (CMIP5) for two future emission scenarios (representative concentration pathways RCP4.5 and RCP8.5) and provide a wide range of potential climate change outcomes. This was carried out using a three-step procedure: calculating the mean annual, monsoon, and non-monsoon precipitation and temperatures; estimating the percent change from historical conditions; and developing scenario funnels and synthetic scenarios. This methodology was applied for the entire south Asia region; however, the percent change information generated at 1.5deg grid scale can be used to generate scenarios at finer spatial scales. Our results showed a high variability in the future change in precipitation (-23% to 52%, maximum in the non-monsoon season) and temperature (0.8% to 2.1%) in the region. Temperatures in the region consistently increased, especially in the Himalayan region, which could have impacts including a faster retreat of glaciers and increased floods. It could also change rivers from perennial to seasonal, leading to significant challenges in water management. Increasing temperatures could further stress groundwater reservoirs, leading to withdrawal rates that become even more unsustainable. The high precipitation variability (with higher propensity for localized intense rainfall events) observed in the region can be a key factor for managed ecosystems and water management and could also lead to more incidence of severe urban flooding. The results could be used to assess both mitigation and adaptation alternatives to reduce vulnerabilities in managed ecosystems (agricultural and urban) and water resources.

agriculture↗