Zincian daubreelite from the Kota-Kota and St. Mark's enstatite chondrites.
Zincian daubreelite from Kota-Kota and St. Mark enstatite chondrites, discussing appearance, occurrence and composition of mineral
Keil, K.↗
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Major lineaments and possible calderas defined by side looking airborne radar imagery, St. Francois Mountains, Missouri
Side-looking radar imagery superiority over aerial photography of geological faults and patterns in St. Francis Mountains, Missouri
Gillerman, E.↗
The ST-224 - A redundant inertial measurement system
ST-224 redundant inertial measurement system, using conventional gimbaled platforms, each with three skewed single-degree-of-freedom control gyro and one caged gyro
Oconnor, B. J.↗
Correlation of ERTS-1 and aircraft optical data with water quality parameters of Charlotte Amalie Harbor, St. Thomas, Virgin Islands
The author has identified the following significant results. Attempts to correlate optical aircraft remote sensing of water quality with the optical data from the ERTS-1 satellite using calibrated imagery of Charlotte Amalie harbor, St. Thomas, Virgin Islands are reported. The harbor at Charlotte Amalie has a concentration of a number of factors affecting water quality: untreated sewage, land runoff, and sediment from navigation and dredging operations. Calibration procedures have been originated and applied to ERTS-1 and I2S camera imagery. The results indicate that the ERTS-1 and I2S imagery are correlated with optical in situ measurements of the harbor water. The aircraft green photographic and ERTS-1 MSS-4 bands have been found most suitable for monitoring the scattered light levels under the conditions of the investigation. The chemical parameters of the harbor water were found to be correlated to the optical properties for two stations investigated in detail. The biological properties of the harbor water (chlorophyll and carotenoids), correlate inversely with the optical data near the pollution sources compared to further away. Calibration procedures developed in this investigation were essential to the interpretation of the photographic and ERTS-1 photometric responses.
Coulbourn, W. C.↗
Soil moisture ground truth, Lafayette, Indiana, site; St. Charles Missouri, site; Centralia, Missouri, site
The soil moisture ground-truth measurements and ground-cover descriptions taken at three soil moisture survey sites located near Lafayette, Indiana; St. Charles, Missouri; and Centralia, Missouri are given. The data were taken on November 10, 1975, in connection with airborne remote sensing missions being flown by the Environmental Research Institute of Michigan under the auspices of the National Aeronautics and Space Administration. Emphasis was placed on the soil moisture in bare fields. Soil moisture was sampled in the top 0 to 1 in. and 0 to 6 in. by means of a soil sampling push tube. These samples were then placed in plastic bags and awaited gravimetric analysis.
Jones, E. B.↗
Exospheric hydrogen above St-Santin /France/
The temperature and hydrogen concentration of the exosphere was determined using incoherent scatter measurements performed above St. Santin from 1969 to 1972. The hydrogen concentration was deduced from measurements of the number density of positive hydrogen and oxygen ions. A statistical analysis is given of the hydrogen concentration as a function of the exospheric temperature and the diurnal variation of the hydrogen concentration is investigated for a few selected days of good quality observation. The data averaged with respect to the exospheric temperature without consideration of the local time exhibits a distribution consistent with a constant effective Jeans escape flux of about 9 x 10 to the 7 cu cm/s. The local time variation exhibits a maximum to minimum concentration ratio of at least 3.5.
Derieux, A.↗
The ST environment: Expected charged particle radiation levels
The external (surface incident) charged particle radiation, predicted for the ST satellite at the three different mission altitudes, was determined in two ways: (1) by orbital flux-integration and (2) by geographical instantaneous flux-mapping. The latest standard models of the environment were used in this effort. Magnetic field definitions for three nominal circular trajectories and for the geographic mapping positions were obtained from a current field model. Spatial and temporal variations or conditions affecting the static environment models were considered and accounted for, wherever possible. Limited shielding and dose evaluations were performed for a simple geometry. Results, given in tabular and graphical form, are analyzed, explained, and discussed. Conclusions are included.
Stassinopoulos, E. G.↗
Long-wave stratospheric transmission of Mount St. Helens ejecta
The NASA/Ames Research C-141 aircraft underflew the Mount St. Helens ejecta plume in Utah three days after the eruption. Upward-looking 20-40-microns on-board radiometry provided data resulting in a calculated long-wave transmission of 0.93. From this value, an optical depth of 0.073 is inferred. This value is compared with an accepted background, stratospheric infrared optical depth of 0.06. Assumptions on particle size, shortwave albedo, and thermal warming imply little surface temperature change caused by the ejecta on the third day immediately following the eruption.
Kuhn, P. M.↗
Trajectories of the Mount St. Helens eruption plume
The plume of the major eruption of Mount St. Helens on May 18, 1980 penetrated 10 to 11 km into the stratosphere, attaining heights of 22 to 23 km. Wind shears rapidly converted the plume from an expanding vertical cone to a thin, slightly inclined lamina. The lamina was extruded zonally in the stratosphere as the lower part moved eastward at jet stream velocities, while the upper part slowly moved westward in the region of nonsteady transition from the westerlies to the summer stratospheric easterlies. Trajectories computed to position the NASA U-2 aircraft for sampling in the plume are described. Plume volume after 8 hours of strong volcanic emission is estimated at 2,000,000 cu km. Only about 1% of this volume is attributed to the volcano; the rest was entrained from the environment.
Danielsen, E. F.↗
Gaseous constituents in the plume from eruptions of Mount St. Helens
Measurements in the stratosphere of gaseous constituents in the plume of Mount St. Helens were obtained during five flights of the NASA U-2 aircraft between 19 May and 17 June 1980. Mixing ratios from gas chromatographic measurements on samples acquired about 24 hours after the initial eruption show considerable enhancement over nonvolcanic concentrations for sulfur dioxide (more than 1000 times), methyl chloride (about 10 times), and carbon disulfide (more than 3 times). The mixing ratio of carbonyl sulfide was comparable to nonvolcanic mixing ratios although 3 days later it was enhanced two to three times. Ion chromatography measurements on water-soluble constituents are also reported. Very large concentrations of chloride, nitrate, and sulfate ions were measured, implying large mixing ratios for the water-soluble gaseous constituents from which the anions are derived. Measurements of radon-222 present in the plume are also reported.
Inn, E. C. Y.↗
Trace element composition of the Mount St. Helens plume - Stratospheric samples from the 18 May eruption
Atmospheric particulate material collected from the stratosphere in the plume of the 18 May 1980 eruption of the Mount St. Helens volcano was quite similar in composition to that of ash that fell to the ground in western Washington. However, there were small but significant differences in concentrations of some elements with altitude, indicating that the stratospheric material was primarily produced from fresh magma, not fragments of the mountain.
Vossler, T.↗
Characterization of aerosols from eruptions of Mount St. Helens
Measurements of mass concentration and size distribution of aerosols from eruptions of Mount St. Helens as well as morphological and elemental analyses were obtained between 7 April and 7 August 1980. In situ measurements were made in early phreatic and later, minor phreatomagmatic eruption clouds near the vent of the volcano and in plumes injected into the stratosphere from the major eruptions of 18 and 25 May. The phreatic aerosol was characterized by an essentially monomodal size distribution dominated by silicate particles larger than 10 micrometers in diameter. The phreatomagmatic eruption cloud was multimodal; the large size mode consisted of silicate particles and the small size modes were made up of mixtures of sulfuric acid and silicate particles. The stratospheric aerosol from the main eruption exhibited a characteristic narrow single mode with particles less than 1 micrometer in diameter and nearly all of the mass made up of sulfuric acid droplets.
Chuan, R. L.↗
Size distributions and mineralogy of ash particles in the stratosphere from eruptions of Mount St. Helens
Samples from the stratosphere obtained by U-2 aircraft after the first three major eruptions of Mount St. Helens contained large globules of liquid acid and ash. Because of their large size, these globules had disappeared from the lower stratosphere by late June 1980, leaving behind only smaller acid droplets. Particle size distributions and mineralogy of the stratospheric ash grains demonstrate inhomogeneity in the eruption clouds.
Farlow, N. H.↗
Absorption of visible radiation by aerosols in the volcanic plume of Mount St. Helens
Samples of particles from Mount St. Helens were collected in both the stratosphere and troposphere for measurement of the light absorption coefficient. Results indicate that the stratospheric dust had a small but finite absorption coefficient ranging up to 2 x 10 to the minus 7 per meter at a wavelength of 0.55 micron, which is estimated to yield an albedo for single scatter of 0.98 or greater. Tropospheric results showed similar high values of an albedo for single scatter
Ogren, J. A.↗
Mount St. Helens aerosol evolution
Stratospheric aerosol samples were collected using a wire impactor during the year following the eruption of Mount St. Helens. Analysis of samples shows that aerosol volume increased for 6 months due to gas-to-particle conversion and then decreased to background levels in the following 6 months.
Oberbeck, V. R.↗
Thermal stability of the surface layer and its relation to the dispersion of primary pollutants in St. Louis
The present investigation is concerned with the applicability of the vertical temperature gradient, DT, as a dispersion parameter for urban area sources. Data on DT were tabulated from temperature measurements at 5 m and 30 m obtained on 30 m towers at 12 stations. DT was obtained by subtracting the value at 5 m from that at 30 m. Positive DT values represent an inversion. Accuracy of the DT data is 0.1 K. Hourly measurements of DT along with concentrations of the primary pollutants, CO, NO, and total hydrocarbons (THC), are available from the 1976 RAPS data base for St. Louis. Linear correlations between a given pollutant species concentration and DT are developed from that data set. It could be confirmed that a strong positive correlation exists at night between the thermal stability of the lowest part of the boundary layer and the urban concentration of the primary pollutants CO, NO, and hydrocarbons.
Remsberg, E. E.↗
Lidar measurements of Mount St. Helens effluents
Lidar measurements of the worldwide movement of stratospheric aerosols produced by the 18 May 1980 eruption of Mount St. Helens are described. Ground-based and airborne measurements show that the layers below 20 km produced by this eruption moved in an easterly direction while those above 20 km moved in a westerly direction. The effluent at jet stream altitudes of 10 to 12 km circled the globe in about 16 days and the effluent at 23 km (the highest altitude recorded) circled the globe in about 56 days. Mass calculations, using backscatter-to-mass conversion models, indicate that approximately half a million metric tons of new stratospheric material were produced by this eruption. Even though this represents a 200% increase in Northern Hemispheric aerosol, no significant long-term atmospheric temperature change should occur.
Mccormick, M. P.↗
Aircraft sampling of the sulfate layer near the tropopause following the eruption of Mount St. Helens
Twenty-three filter sampling flights of the NASA Lewis F-106 aircraft, were conducted in the Great Lakes region between June 4 and Dec. 23, 1980, following the major eruption of Mount St. Helens on May 18. The IPC-1478 filters were exposed over an altitude range spanning the local tropopause. A filter sample exposed above the tropopause on June 5 indicated a sulfate level 50 times the baseline measurements, which is consistent with the trajectory predictions of the leading edge of the cloud on its second transit around the earth. Subsequent measurements over a period of 7 months revealed the existence of a layer of sulfate above the tropopause that decayed to a level of about 4 times previously measured background levels by the beginning of August. Concentration of nitrate above the tropopause exhibited considerable variability and showed some enhancement compared with previously measured concentration levels. On the basis of the null results of X ray fluorescence measurements, there is no evidence of ash particle concentrations of greater than 3.4 microns/cu m persisting in the layer above the tropopause following the second transit of the cloud.
Lezberg, E. A.↗