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DOE OSTI2020

NNSS Soils Monitoring: Plutonium Valley (CAU 366) FY2019

Desert Research Institute (DRI) conducted a field assessment of the potential for radionuclide-contaminated soil to be transported from the Plutonium Valley Dispersion Sites Contamination Area (CA) because of both wind and storm water runoff. This activity supported U.S. Department of Energy (DOE) Environmental Management Nevada Program (EM NV) efforts to establish post-closure monitoring plans for the Plutonium Valley Dispersion Sites Corrective Action Unit (CAU) 366. The DRI task was intended to identify the likely mechanism(s) of transport and determine the meteorological conditions that might cause the movement of radionuclide-contaminated soils. The emphasis of the work was on collecting sediment transported by channelized storm runoff and measuring airborne dust concentrations and associated wind conditions. These data will facilitate an appropriate post-closure monitoring program. In 2011, DRI installed meteorological monitoring stations north and south of the Plutonium Valley CA—known as Pu Valley North and Pu Valley South, respectively—as well as a fluvial sediment sampling station within the CA. Since installation, temperature, wind speed, wind direction, relative humidity, precipitation, solar radiation, barometric pressure, soil temperature, volumetric soil moisture content, and airborne particulate concentrations have been collected at both meteorological stations. The maximum, minimum, and average or total (as appropriate) for each of these parameters were recorded for each 10-minute interval. The sediment sampling station included an automatically activated sampling pump with collection bottles for suspended sediment, which was activated when sufficient flow was present in the channel, and passive traps for bedload material that was transported down the channel during runoff events. This report presents data collected from these stations during fiscal year (FY) 2019. During the FY2019 (October 1, 2018, through September 30, 2019) reporting period, the warmest month was July and the coldest month was February. Monthly total solar radiation was highest in June or July (depending on the station) and lowest in December. Monthly mean wind speeds were highest during February. At the Pu Valley North station, winds were commonly northerly, northwesterly, and southerly. At the Pu Valley South station, the wind direction was more variable and winds frequently came from most directions, excluding westerly and northwesterly winds. Winds above 15.0 miles per hour (mph) (24.1 kilometers per hour [km/hr]) were frequently southerly at both stations, and less-frequent strong winds were northerly (at the Pu Valley South station) or northwesterly (at the Pu Valley North station). Monthly average relative humidity ranged from 18 percent in August to 62 percent in January and February. Monthly total precipitation ranged from zero at both stations in September to 2.23 inches (in) (56.6 millimeters [mm]) during February at the Pu Valley South station and 2.09 in (53.1 mm) during March at the Pu Valley North station. From October 1, 2018, through September 30, 2019, the total precipitation was 8.23 in (209 mm) and 8.15 in (207 mm) at the Pu Valley South and Pu Valley North stations, respectively. The largest daily precipitation totals of 1.46 in (37.1 mm) and 1.14 in (29.0 mm) occurred at the Pu Valley South and Pu Valley North stations, respectively, on March 6, 2019. However, the ISCO autosampler was not activated during any storm event in FY2019 because the channel water depth measurements were insufficient for suspended sediment sample collection. Additionally, because no significant flow through the channel was indicated, no bedload samples were collected. Light breezes of 0.0 mph to 5.0 mph (0.0 km/hr to 8.0 km/hr) occurred most frequently (approximately 55 percent to 57 percent of the time). The frequency of occurrence diminished exponentially as the wind speed increased such that winds in excess of 25.0 mph (40.2 km/hr) occurred less than 0.01 percent of the time. Winds in excess of 15.0 mph (24.1 km/hr) were most commonly southerly, which is likely controlled by the topography of the valley because topographic highs define the east and west sides of the valley and converge toward the north.The concentrations of PM2.5 (particulate matter with an aerodynamic diameter ≤2.5 micrometers [μm]) and PM10 (particulate matter with an aerodynamic diameter ≤10 μm) in the air generally increase as wind speed increases. However, the particle profiler at the Pu Valley South station regularly malfunctioned, which resulted in poor data quality and a limited period of record within FY2019. Therefore, discussion of the annual dust observations is mostly limited to the Pu Valley North station. At the Pu Valley North station, significant increases in windblown dust concentrations were observed when wind speeds exceeded 15.0 mph (24.1 km/hr), especially during southerly winds. When all wind speeds were considered, high dust concentrations at the Pu Valley North station were frequently associated with northerly, northwesterly, or southerly winds. The majority of PM10 transport at the Pu Valley North station occurred when winds were blowing northerly and northwesterly because of the high frequency of winds up to 15.0 mph (24.1 km/hr). The ratio of PM10 to PM2.5 is a qualitative indicator of the proximity of dust sources to the observation point and the values of the PM10 to PM2.5 ratio tend to be higher nearer to the source. The PM10 to PM2.5 ratio increased from 1.2 to 2.8 with higher wind speeds at the Pu Valley North station. This increase suggests that some locally sourced PM10 was present in the air when local winds exceeded 15.0 mph (24.1 km/hr). Local dust suspension is interpreted during major dust events when peaks in the PM10 to PM2.5 ratio occur simultaneously with the maximum wind speed and the peak PM10 concentration. Analysis of the five major dust events in FY2019 revealed that northerly winds were dominant in three events and southerly winds were dominant in two events. Local suspension of dust within Plutonium Valley is suspected to have occurred during two of the five major events (April 9, 2019, and September 28 to 29, 2019), and a nonlocal source of dust is presumed for the three other major dust events (October 14, 2018; May 16, 2019; and September 2, 2019). The three suspected regional dust transport events exhibited winds that typically did not exceed the 15.0 mph (24.1 km/hr) wind speed threshold for local dust transport and featured PM10 to PM2.5 ratios that indicate large-scale regional dust transport. Similar event characteristics (e.g., wind speed and PM10 concentration) were observed at air monitoring stations approximately 70 mi (113 km) to the northwest within the Tonopah Test Range (TTR). Therefore, these three regional events may not reflect transport from the Plutonium Valley CA. Routine monitoring of meteorological and hydrologic parameters at Plutonium Valley has been discontinued at the request of EM NV, effective at the conclusion of FY2019. Environmental data acquisition has been completed, and both Pu Valley North and Pu Valley South meteorological stations within Plutonium Valley as well as the ISCO autosampler station within the CA were removed on October 14, 2019.

54 ENVIRONMENTAL SCIENCES↗

NASA NTRS1990

An estimate of the maximum speed of the solar wind, 1938-1989

In an effort to estimate the highest flow velocity that the solar wind has exhibited at earth during the past 50 years, geomagnetic storms that occurred from 1938 to 1989 were surveyed, and the storms that were preceded by a major proton flare were selected. For each identified flare-storm pair, the average speed ('transit speed') of the associated interplanetary shock from the interval between the flare onset and the sudden commencement of the geomagnetic storm was calculated. In each case, the maximum solar wind flow speed was inferred from an empirical relationship (derived for a sample of recent events) between the shock transit speed and the peak flow velocity of the associated transient stream, obtaining a distribution of maximum solar wind speeds, which presumably corresponds to a sample of the most energetic events of this 50-yr period. Results show no evidence for bulk flow velocities greater than the about 2000 km/sec value deduced by Zastenker et al. (1978) and Grunwaldt (1975) for the August 4, 1972 event.

Cliver, E. W.↗

DOE OSTI2022

Revisiting the Definition of Rapid Intensification of Tropical Cyclones by Clustering the Initial Intensity and Inner‐Core Size

Abstract Rapid intensification (RI) of tropical cyclones (TCs) provides a great challenge in operational forecasting and contributes significantly to the development of major TCs. RI is commonly defined as an increase in the maximum sustained surface wind speed of at least a certain threshold within 24 hr. The most widely used threshold is 30 kt (15.4 m/s), which was determined statistically. Here we propose a new definition for RI by objectively clustering TCs using the intensification rate, initial intensity, and radius of the maximum wind speed (RMW). A group of 770 samples is separated at a threshold of 45 kt (23.2 m/s). The threshold is 40 kt (20.6 m/s) for the western North Atlantic, where TC size measurements are more reliable. Monte Carlo experiments demonstrate that the proposed threshold is robust even considering the uncertainty in RMW of as high as 30 km. We show that, when a TC undergoes RI, its maximum wind speed is approximately 60 ± 15 kt (30.9 ± 7.7 m/s) and the RMW is 45 ± 20 km. The new threshold outperforms the conventional threshold of 30 kt/24 hr in describing the bimodal distribution of lifetime maximum intensity and explaining the annual count of Category 5 TCs. This new definition provides a more physically based threshold and describes a more reliable representation of extreme events. Although more comparisons are needed for operational application, it is likely to be desirable for case‐based process studies and could provide a more valuable metric for TC intensification classification and research.

Li, Yi↗

NASA NTRS1974

Lunar Science Conference, 5th, Houston, Tex., March 18-22, 1974, Proceedings. Volume 1 - Mineralogy and petrology. Volume 2 Chemical and isotope analyses. Organic chemistry. Volume 3 - Physical properties

Numerous studies on the properties of the moon based on Apollo findings and samples are presented. Topics treated include ages of the lunar nearside light plains and maria, orange material in the Sulpicius Gallus formation at the southwestern edge of Mare Serenitatis, impact-induced fractionation in the lunar highlands, igneous rocks from Apollo 16 rake samples, experimental liquid line of descent and liquid immiscibility for basalt 70017, ion microprobe mass analysis of plagioclase from 'non-mare' lunar samples, grain size and the evolution of lunar soils, chemical composition of rocks and soils at Taurus-Littrow, the geochemical evolution of the moon, U-Th-Pb systematics of some Apollo 17 lunar samples and implications for a lunar basin excavation chronology, volatile-element systematics and green glass in Apollo 15 lunar soils, solar wind nitrogen and indigenous nitrogen in Apollo 17 lunar samples, lunar trapped xenon, solar flare and lunar surface process characterization at the Apollo 17 site, and the permanent and induced magnetic dipole moment of the moon. Individual items are announced in this issue.

Gose, W. A.↗

NASA NTRS1972

Carbon chemistry of Apollo 14 size-fractionated fines.

Experiments have been conducted on several Apollo 12 and 14 samples that confirm the identification of CH4 and C2H6 in lunar fines and breccias. In particular, data for various size fractions of sample 14240,5 are reported which show that the concentrations of these species are dependent on particle size. Results strongly support proposals that solar wind activity is a source of CH4 in lunar samples.

Holland, P. T.↗

NASA NTRS1976

The Surface Chemical Composition of Lunar Samples and Its Significance for Optical Properties

The surface iron, titanium, calcium, and silicon concentration in numerous lunar soil and rock samples was determined by Auger electron spectroscopy. All soil samples show a large increase in the iron to oxygen ratio compared with samples of pulverized rock or with results of the bulk chemical analysis. A solar wind simulation experiment using 2 keV energy alpha -particles showed that an ion dose corresponding to approximately 30,000 years of solar wind increased the iron concentration on the surface of the pulverized Apollo 14 rock sample 14310 to the concentration measured in the Apollo 14 soil sample 14163, and the albedo of the pulverized rock decreased from 0.36 to 0.07. The low albedo of the lunar soil is related to the iron + titanium concentration on its surface. A solar wind sputter reduction mechanism is discussed as a possible cause for both the surface chemical and optical properties of the soil.

Gold, T.↗

DOE OSTI2021

Dependence of Solar Wind Proton Temperature on the Polarization Properties of Alfvénic Fluctuations at Ion-kinetic Scales

In this work, we use fluctuating magnetic helicity to investigate the polarization properties of Alfvénic fluctuations at ion-kinetic scales in the solar wind as a function of β p , the ratio of proton thermal pressure to magnetic pressure, and θ vB , the angle between the proton flow and local mean magnetic field, B 0 . Using almost 15 yr of Wind observations, we separate the contributions to helicity from fluctuations with wavevectors, k, quasi-parallel and oblique to B 0 , finding that the helicity of Alfvénic fluctuations is consistent with predictions from linear Vlasov theory. This result suggests that the nonlinear turbulent fluctuations at these scales share at least some polarization properties with Alfvén waves. Furthermore, we also investigate the dependence of proton temperature in the β p –θ vB plane to probe for possible signatures of turbulent dissipation, finding that it correlates with θ vB . The proton temperature parallel to B 0 is higher in the parameter space where we measure the helicity of right-handed Alfvénic fluctuations, and the temperature perpendicular to B 0 is higher where we measure left-handed fluctuations. This finding is inconsistent with the general assumption that by sampling different θ vB in the solar wind we can analyze the dependence of the turbulence distribution on θ kB , the angle between k and B 0 . After ruling out both instrumental and expansion effects, we conclude that our results provide new evidence for the importance of local kinetic processes that depend on θ vB in determining proton temperature in the solar wind.

79 ASTRONOMY AND ASTROPHYSICS↗

NASA NTRS1981

Determination of surface stress by Seasat-SASS - A case study with JASIN data

The values of sea surface stress determined with the dissipation method and those determined with a surface-layer model from observations on F.S. Meteor during the Joint Air-Sea Interaction (JASIN) Experiment are compared with the backscatter coefficients measured by the scatterometer SASS on the satellite Seasat. This study demonstrates that SASS can be used to determine surface stress directly as well as wind speed. The quality of the surface observations used in the calibration of the retrieval algorithms, however, is important. This sample of measurements disagrees with the predictions by the existing wind retrieval algorithm under non-neutral conditions and the discrepancies depend on atmospheric stability.

Liu, W. T.↗

NASA NTRS1991

Effect of particle size of Martian dust on the degradation of photovoltaic cell performance

Glass coverglass and SiO2 covered and uncovered silicon photovoltaic (PV) cells were subjected to conditions simulating a Mars dust storm, using the Martian Surface Wind Tunnel, to assess the effect of particle size on the performance of PV cells in the Martian environment. The dust used was an artificial mineral of the approximate elemental composition of Martian soil, which was sorted into four different size ranges. Samples were tested both initially clean and initially dusted. The samples were exposed to clear and dust laden winds, wind velocities varying from 23 to 116 m/s, and attack angles from 0 to 90 deg. It was found that transmittance through the coverglass approximates the power produced by a dusty PV cell. Occultation by the dust was found to dominate the performance degradation for wind velocities below 50 m/s, whereas abrasion dominates the degradation at wind velocities above 85 m/s. Occultation is most severe at 0 deg (parallel to the wind), is less pronounced from 22.5 to 67.5 deg, and is somewhat larger at 90 deg (perpendicular to the wind). Abrasion is negligible at 0 deg, and increases to a maximum at 90 deg. Occultation is more of a problem with small particles, whereas large particles (unless they are agglomerates) cause more abrasion.

Gaier, James R.↗

NASA NTRS1980

Instrumented aircraft verification of clear-air radar detection of low-level wind shear

A technique is described in which the longitudinal wind component at airports, measured by Doppler radar, is put through a Fourier transformation to produce an energy density spectrum. The result is multiplied by the aircraft response characteristics to produce quantitative data on aircraft performance in a wind shear situation. The Doppler radar measurements are made along the intended flight path. Two case studies, along a 3 deg approach path, are described from measurements in two modes: Lagrangian, where predictions were computed one range gate ahead of the plane, and Eulerian, where samples were measured instantaneously along the flight path. Wind data obtained every second were interpolated to fit a numerical model by using a cubic spline. Eulerian data were superior to Lagrangian data in terms of ranging, and nearly equal for wind speeds. Improvements in current 75% accuracy are noted to be possible with shrouded antennas to reduce sidelobes and use of Doppler radar with higher resolution to eliminate effects of small scale disturbances within the pulse volume.

Mccarthy, J.↗

NASA NTRS1998

Aerothermal Effects of Cavities and Protuberances for High-Speed Sample Return Capsules

Extraterrestrial sample return is a growing component of solar system exploration. Currently, four missions, Stardust, 1 Muses-C, 2 Genesis, and Mars Sample Return, are under development that employ sample return as a prime component of the mission architecture. Respectively, these missions will return samples from the tail of a comet, an asteroid, the solar wind, and, Mars. An important component of these missions and the focus of this paper is the design of the sample return capsule (SRC). The purpose of the SRC is to safely return to Earth any gathered samples for terrestrial analysis. The two major design constraints for any SRC are as follows: 1) it must be able to survive a high-speed Earth entry (11 km/s to as a high as 15 km/s), 2) the mass of the SRC must be as small as possible. Because the SRC mass is carried from Earth to the sample sight and back, the SRC mass is a strong driver in the mission mass budget. Further, for the Mars Sample Return Capsule, planetary protection is another constraint. For this capsule, the probability of planetary contamination at Earth due to an SRC failure at entry must be minimal. For an SRC, a possible failure mechanism is severe local heating as a result of cavities and or protuberances in the SRC forebody heatshield. For example, the Apollo Command Module had a number of cavities and protuberances as part of the baseline designs Wind-tunnel tests of models containing small cavities and protuberances showed severe local heating augmentations in the vicinity of these surface discontinuities.4-5 As another example, the Genesis SRC forebody heat-shield contains penetrations (cavities) to mount the vehicle to the carrier bus. It is expected that these penetrations will also experience a severe local heating environment. A concern is that the large thermal gradients may produce sufficient thermal stress to cause local mechanical failure of the heatshield. Penetrations to the forebody heat-shield can also result from damage at vehicle integration, during launch, or during transportation of the sample return capsule from earth to the sample site and back. For example, the Starting SRC was damaged near the shoulder during the heatshield integration process producing a local surface discontinuity. Also, the Starting SRC traverses through the tail of a comet and is in space for 7 years. Thus, damage to the heatshield as a result of micrometeroid impact is a concern. Finally, it is difficult to characterize the effects of these potential heatshield singularities with ground-test facilities. Either detailed simulation or a dedicated flight test is required.

Olynick, David↗

NASA NTRS2004

Wind Measurements with High Energy 2 Micron Coherent Doppler Lidar

A coherent Doppler lidar based on an injection seeded Ho:Tm:YLF pulsed laser was developed for wind measurements. A transmitted pulse energy over 75 mJ at 5 Hz repetition rate has been demonstrated. Designs are presented on the laser, injection seeding, receiver, and signal processing subsystems. Sample data of atmospheric measurements are presented including a wind profile extending from the atmospheric boundary layer (ABL) to the free troposphere.

Barnes, Bruce W.↗

NASA NTRS2012

Kinetic and Potential Sputtering Enhancements of Lunar Regolith Erosion: The Contribution of the Heavy Multicharged (Minority) Solar Wind Constituents

We report preliminary results for H+, Ar+1, Ar+6 and Ar+9 ion sputtering of JSC-1A lunar regolith simulant at solar wind velocities, obtain ed at the ORNL Multicharged Ion Research Facility using quadrupole ma ss spectrometry. The multi-charged Ar ions were used as proxies for i ntermediate mass solar wind multicharged ions. Prior to the Ar beam e xposures, the sample was exposed to high fluence H+ irradiation to si mulate H-loading due to the dominant solar wind constituent. A x80 en hancement of oxygen sputtering by Ar+ over same velocity H+ was measu red and an additional x2 increase for Ar+9 over same velocity Ar+ was demonstrated, giving clear evidence of the importance of potential s puttering by multicharged ions. This enhancement was observed to pers ist to the maximum fluences investigated (approx 10(exp 16)/sq cm). As discussed in a companion abstract by N. Barghouty, such persistent s puttering enhancement has significant implications on weathering and aging of lunar regolith. In addition, XPS measurements showed strong evidence of Fe reduction for those target areas that had been exposed to high fluence Ar+ and Ar+8 beams. Preferential oxidation of the Fe -reduced beam-exposed regions during transfer to the XPS system led t o enhanced O concentrations in those regions as well. On the basis of these very promising preliminary results, a NASA-LASER project on mo re extensive measurements was recently selected for funding. The prop osal expands the collaboration with NASA-MSFC for the simulation effort, and adds a new collaboration with NASA-GSFC for lunar mission-rele vant measurements.

Meyer, F. W.↗

NASA NTRS1983

Effects of wind on turbofan engines in outdoor static test stands

Wind can affect measured thrust and can cause turbofan engine speed to fluctuate during outdoor testing. Techniques used at an outdoor test stand at NASA Lewis Research Center to make testing easier and faster and to improve data repeatability include using an inflow control device (ICD) to make fan speed steadier, taking many raw data samples for better averaging, and correcting thrust for wind direction and speed. Data from engine tests are presented to show that the techniques improve repeatability of thrust and airflow measurements under various wind conditions.

Mcardle, J. G.↗

NASA NTRS1983

Effects of wind on turbofan engines in outdoor static test stands

Mcardle, J. G.↗

NASA NTRS1971

The measurement of radiation exposure of astronauts by radiochemical techniques

Gamma analyses of the neutron-activated fecal samples from the Apollo 12 and 13 missions were completed, and the data are being evaluated. Samples of the exposed Apollo 12 solar wind composition foil and blank foils were obtained for analysis of the Po-2/0 (Pb-210, Rn-222) content. It is expected that the determination of the Po-210 content of these foils will yield the concentration of radon atoms incident on the foil while exposed to the lunar atmosphere, and this indirectly will permit an estimate of the average uranium concentration of the lunar surface. Proposals to measure the cosmic-ray intensity and energy spectra inside and outside of late Apollo and Project Skylab spacecraft by exposing and subsequently analyzing pure metal foils, and to measure the elemental mass balance in Project Skylab astronauts by instrumental neutron activation analysis of the intake and excreta are summarized.

Brodzinski, R. L.↗

NASA NTRS1972

Compounds of carbon and other volatile elements in Apollo 14 and 15 samples.

DF dissolution and pyrolysis showed that the indigenous methane and ethane contents in Apollo 14 and 15 lunar samples correlated with the amounts of solar wind gases and the deutero-carbon reaction gases. Pyrolysis evolved mainly CO and N2 and lower amounts of CO2. Other compounds detected and quantitated by these techniques were DCN, HCN, CS2, D2S, and PD3.

Holland, P. T.↗

NASA NTRS1976

Atmospheric turbulence power spectral measurements to long wavelengths for several meteorological conditions

Use of power spectral design techniques for supersonic transports requires accurate definition of atmospheric turbulence in the long wavelength region below the knee of the power spectral density function curve. Examples are given of data obtained from a current turbulence flight sampling program. These samples are categorized as (1) convective, (2) wind shear, (3) rotor, and (4) mountain-wave turbulence. Time histories, altitudes, root-mean-square values, statistical degrees of freedom, power spectra, and integral scale values are shown and discussed.

Rhyne, R. H.↗