bluuebunny/crossref_metadata_2025 huggingface dataset:
Size Distribution of phytoplankton in the central and eastern tropical Pacific
Authors: Chavez Francisco P.
Published: February 2008

Size separations of phytoplankton biomass and production were performed with Nuclepore filters in the central and eastern tropical Pacific. The results show that there is a relationship between size and distance from land forms, with larger aggregates of phytoplankton dominating close to shore and small (less than 1 μm) forms dominating offshore. Surface nutrient concentrations were high in the offshore regions of equatorial upwelling and there was no apparent relationship between nutrient concentration and size. The phytoplankton biomass and production in the equatorial Pacific from 90°W to 150°W are dominated by small algae which are not retained by 5 μm Nuclepore filters with these organisms accounting for over 80% of the biomass and production. It is hypothesized that the dominance of small forms, as well as the relatively low plant biomass found, is the result of the absence of neritic bloom‐forming centric diatoms in offshore regions. The fact that small phytoplankton dominate in the equatorial Pacific suggests a dynamic food web. A dynamic food web coupled with the vigorous horizontal circulation of the equatorial Pacific supports the notion that some of the new nitrogen upwelled in this region is first exported laterally and then vertically.
Dissolved, particulate and acid‐leachable trace metal concentrations in North Atlantic precipitation collected on the Global Change Expedition
Authors: Lim B. , Jickells T. D.
Published: February 2008

Rainwater samples from six precipitation events were collected on board ship during legs 3 and 4 of the Global Change Expedition over the North Atlantic Ocean and analyzed for dissolved, particulate (Al and Pb), and acid‐leachable trace metals (Al, Fe, Mn, Cd, Cu, Pb, Zn). Acid‐leachable concentrations of the elements (in 0.4% v/v HNO3) were similar to reported values from the North Atlantic and Pacific oceans which were measured using comparable acidification procedures. Concentrations of dissolved and particulate Al and Pb were determined in rain events concurrently sampled. Comparisons between acid‐leachable and total (dissolved plus particulate) trace metal concentrations suggest that the acid‐leachable fraction of metals can significantly underestimate total concentrations of crustal elements (e.g., Al) in rain). The solubilities of Al and Pb in precipitation were variable and mean solubilities of the elements were 13% and 45%, respectively. Recycled sea salt components were less than 14% for Al, Fe, Mn, Pb, Cd, Cu, and Zn, indicating that the net trace metal flux is from the atmosphere to the oceans. Deep‐sea particle fluxes for these metals through the western tropical North Atlantic exceed atmospheric deposition fluxes by a factor of 18‐41.
Low orthopyroxene from a lunar deep crustal rock: A new Pyroxene polymorph of space group P21ca
Authors: Smyth Joseph R.
Published: February 2008

Bronzite crystals (En86 Fs11Wo3) from a slowly‐cooled lunar troctolitic granulite, have space group P21ca, a postulated, but previously unreported space group. Diffractions violating the b‐glide extinction conditions have been observed in long‐exposure X‐ray precession photographs from three of these crystals and on an automated X‐ray diffractometer. P21ca is a subgroup of the common orthopyroxene space group Pbca, and cell dimensions; a = 18.235 ± 0.004 Å, b = 8.831 ± 0.002 Å c = 5.189 ± 0.001 Å are similar to those of terrestrial bronzites. It is postulated that the lower symmetry space group has developed as a result of very slow cooling at pressures of one to two kilobars deep in the lunar crust.
Three‐dimensional air motion measured in snow
Authors: Frisch A. S. , Miller L. J. , Strauch R. G.
Published: February 2008

In this letter, we present the results of a method that uses two Doppler radars to observe the three‐dimensional wind field during light snowfall. These radars are designed to scan in a series of tilted planes, passing through the two radar positions. From the mean Doppler shifts in the frequency spectra we can determine average radial velocities within the pulse volumes. Since the two radars do not observe the same volume increments at the same time, spatial interpolation is needed before the radial velocities can be combined into a two‐dimensional velocity field at a set of common coordinates within each plane. The estimated terminal fall velocity of the snow is subtracted from the particle velocity to obtain the true air motion in the plane. The air motion component normal to the plane is obtained by integrating the equation of continuity in cylindrical coordinates starting with the surface boundary condition at the plane of zero elevation. The velocity field in the common planes scanned by the radars is then transformed into a rectangular coordinate system with one axis oriented parallel to the average wind direction. After the mean wind field is removed from the results, a well organized “eddy” wind field is evident.
A deep research drill hole at the summit of an active volcano, Kilauea, Hawaii
Authors: Zablocki Charles J. , Tilling Robert I. , Peterson Donald W. , Christiansen Robert L. , Keller George V. , Murray John C.
Published: February 2008

Drilling and geophysical logging data for a 1,262 m‐deep bore hole in the area inferred to overlie the magma reservoir of Kilauea Volcano, Hawaii, support earlier interpretations based on surface geophysical surveys that a zone of brackish or saline water lies above the reservoir. Temperatures encountered within the hole are not sufficiently high to warrant commercial interest; the maximum temperature, 137°C, is at the hole bottom. However, the temperature gradient toward the bottom of the hole (approximately 160 m below sea level) increases sharply to about 370°C/km, perhaps partly reflecting the effect of decreased water circulation as suggested by the geophysical logging data. If this gradient persists or increases with depth, magmatic temperatures would be attained within 3 km from the hole bottom (i.e., approximately 4 km from ground surface)—a depth in accord with data from ground‐deformation and seismic studies.
Comparison of experimental and computed values for j(NO2)
Authors: Stedman D. H. , Chameides W. , Jackson J. O.
Published: February 2008

A comparison is made between two independent measurements and calculated values of j (NO2), the photolysis frequency of NO2. The calculated value was approximately 2% greater than the frequency implied by observations. This discrepancy is small enough to confirm the general accuracy of the computational technique and its associated input parameters.
Photochemistry of hydrocarbons in the Jovian upper atmosphere
Authors: Prasad S. S. , Capone L. A. , Schneck L. J.
Published: February 2008

The recently suggested possibility of catalytic destruction of H by C2H2in the Jovian upper atmosphere has been examined. For this purpose we discuss a relatively more detailed chemistry, including the possible role of the reaction C2H2+ C2H3→ C4H5*→ C4H4+ H, and wish to suggest that the catalytic destruction of atomic hydrogen is quite questionable at least under the present paucity of the required reaction rate data. Attention is also drawn to the importance of the temperature dependence of the rate coefficients in discussing Jovian aeronomy.
Satellite observations of the nitric oxide nightglow
Authors: Gerard Jean‐Claude
Published: February 2008

The NO δ‐bands have been observed photometrically by the ultraviolet telescope onboard the TD‐1 ESRO satellite. The maximum intensity for the system is about 220 R, in good agreement with a previous rocket measurement. Assuming that the excitation is due to the N + O → NO(C²Π, v=0) preassociation, we used the observed profile to derive the atomic nitrogen density distribution. We found a peak of about 9 × 107 cm−3 at about 180 km. A comparison is made with theoretical predictions, and some implications of such a high N(4S) density are discussed.
Pressure‐induced coordination changes in magmatic liquids
Authors: Waff Harve S.
Published: February 2008

It is probable that many of the gross physical properties of melts and partial melts at depth within the earth are substantially modified by pressure‐induced cationic coordination transformations. An isochemical extension of the Bottinga‐Weill viscosity model is suggested to account for the effects of coordination changes on melt viscosities. Resulting predictions are that tholeiitic and andesitic melts will undergo, with increasing pressure, decreases in viscosity of factors of 14 and 47 respectively on transformation of aluminum from four‐ to six‐fold oxygen coordination. Analogous transformations in solid phases suggest their occurrence in melts at pressures below 35 kilobars for temperatures not exceeding 1400C. Associated changes in liquid specific volume are estimated to be roughly three and four percent respectively for the aforementioned melt compositions. Transformation of aluminum from four‐ to six‐coordination also greatly decreases shear wave attenuation in partial melts.
Helium survey, A possible technique for locating geothermal reservoirs
Authors: Roberts Alan A. , Friedman Irving , Donovan Terrence J. , Denton Edward H.
Published: February 2008

Measurements were made of the helium concentration in the soil gases surrounding the Indian Hot Springs, Idaho Springs, Colorado. The helium concentration was shown to vary in a regular manner from the background level of 5.2 ppm to a high of more than 100 ppm near a warm (26°C) water seep, and more than 1,000 ppm near a hot (40°C) water seep. Such an association of helium in the soil gas with these hot waters near the earth's surface suggests the possible utility of helium surveys in locating hidden geothermal reservoirs.
Estimate of late 1974 stratospheric concentration of gaseous chlorine compounds (ClX)
Authors: Cicerone R. J. , Stedman D. H. , Stolarski R. S.
Published: February 2008

We estimate the total concentration [ClX] versus altitude of Cl‐containing molecules, principally HCl, Cl and ClO. The predicted present stratospheric concentrations appear to be due to photolysis near 30 km of man‐made CF2Cl2 and CFCl3, and CCl4 from a ground‐level source, man‐made or natural. Based on preliminary measurements of CH3Cl at ground we estimate its contribution to stratospheric ClX through the major known loss mechanism for CH3Cl, abstraction by OH. Ground‐level sources of HCl and Cl2 are large but tropospheric processes preclude significant impact on the stratosphere. Our computed profiles are consistent with first HCl concentrations measured by Lazrus et al. [1974, 1975] in the 15–27 km region.
Observation of the Farley‐Buneman Instability in laboratory plasma
Authors: John P. I. , Saxena Y. C.
Published: February 2008

An experiment simulating certain characteristics of the equatorial electrojet plasma (viz. Ve»re Vi ≳ ri) is described. High frequency (W ≳ Vi > ri) instabilities are observed when electrons stream in the E × B direction past ions with a velocity exceeding the ion acoustic speed. The observed phase velocities and frequencies agree with the results of the Farley‐Buneman instability theory, modified to take account of finite k∥. The measured instability spectrum for potential fluctuations goes as k−n⊥ with n = 2–3.5
Equations of turbulent diffusion in shear flows
Authors: Kao S. K.
Published: February 2008

An analysis of the characteristics of the eddy diffusivity is made, and the equations for turbulent diffusion in shear flows are derived. It is shown that the coefficients of the eddy diffusion can be expressed in terms of the stress tensor of the turbulent motion, a characteristic time and the velocity shear of the mean flow, which can be readily determined.
Evidence for local ion heating in solar wind high speed streams
Authors: Bame S. J. , Asbridge J. R. , Feldman W. C. , Gary S. Peter , Montgomery Michael D.
Published: February 2008

The thermal anisotropies near the peaks of proton distributions are observed to vary characteristically across two simple high speed streams. Before the time of maximum velocity gradient T∥ of the core distribution is greater than T⊥ but afterwards, and persisting throughout the remainder of the high speed region, T∥ < T⊥. This implies that it may not be necessary to invoke extended ion heating close to the sun to explain enhanced ion temperatures associated with high speed streams and that the T‐V relation may be primarily the result of local heating near 1 AU.
Winter bulge and diurnal variations in hydrogen inferred from AE‐C composition measurements
Authors: Brinton H. C. , Mayr H. G. , Potter W. E.
Published: February 2008

The atomic hydrogen distribution at 250 km during December 1974 solstice has been inferred, considering charge exchange equilibrium, from Atmosphere Explorer‐C measurements of n(H+), n(O+), and n(O). An empirical model, derived from the observations by least square analysis in terms of spherical harmonics, has the following characteristics: (a) n(H) increases by as much as a factor of two between the summer and winter hemispheres, (b) the n(H) diurnal variation is largest at the equator where nmax/nmin = 3.2, the maximum occurring at 03h LT, and (c) the diurnal variation is larger in the winter hemisphere ( nmax/nmin = 2.6 at +40°) than in the summer (nmax/nmin = 2.3 at −40°). Similar analysis of the gas temperature derived from n(N2) measurements reveals that all n(H) and Tg spherical harmonic coefficients are anticorrelated. Both the diurnal and latitudinal (annual) n(H) and Tg amplitudes are in substantial agreement with the “zero flux condition,” in which exospheric flow dominates the hydrogen distribution. The observed diurnal phase lag of n(H) with respect to Tg is about one hour, agreeing with theory. During the period of measurement the observed mean global values of Tg and n(H) were 800K and 3.6 × 105 cm−3, respectively, the latter exceeding the Kockarts‐Nicolet model concentration by a factor of two.
Temperature profile in the molecular sublayer near the interface of a fluid in turbulent motion
Authors: Liu W. Timothy , Businger Joost A.
Published: February 2008

The molecular sublayers adjacent to the air‐sea interface are assumed to undergo cyclic growth and destruction in order to explain the exponential temperature profiles measured by Khundzhua and Andreyev. The duration of such cycles is taken to be randomly distributed in forced convection and a constant period is used to determine the temperature profile in free convection.
Spatially periodic lead patterns in the Canada Basin Sea Ice: A possible relationship to planetary waves
Authors: Marko J. R. , Thomson R. E.
Published: February 2008

Satellite imagery of the ice‐covered Canada Basin in the Arctic Ocean shows the presence of large‐scale, spatially rectilinear leads separated by distances of ∼100 km. Consideration of the scales and other characteristics of these phenomena indicated the underlying water mass to be the most likely driving agent. An interpretation in terms of the reflection of planetary waves originating from the northern Basin, self consistently and in accord with other information, describes many of the observational features.
Stratospheric halogen measurements
Authors: Lazrus A. L. , Gandrud B. W. , Woodard R. N. , Sedlacek W. A.
Published: February 2008

A method for efficient collection of stratospheric hydrogen chloride has been developed. Initial measurements for HCl, HBr and particulate Cl and Br are given.
Stratospheric profiles of CCl3F and CCl2F2
Authors: Heidt L. E. , Lueb R. , Pollock W. , Ehhalt D. H.
Published: February 2008

This is a brief note intended to report recent measurements of CCl3F and CCl2F2 in stratospheric samples obtained in 1973 through 1975. The samples were collected by a balloon‐cryogenic sampling system which has been described previously (Lueb, Ehhalt, and Heidt, 1975). The method allows us to collect large air samples (10 ℓ STP) for the laboratory analysis of a number of trace gases. It has been used since September 1973. Aliquots of the samples had been stored and were analyzed this year for their halocarbon content by gas chromatography with an electron capture detector. Results of these measurements are compared to calculated predictions.
Observation of the cross‐field instability in laboratory plasma
Authors: Saxena Y. C. , John P. I.
Published: February 2008

In an experiment simulating certain characteristics of the equatorial electrojet plasma
low frequency
waves travelling in
direction are observed. These waves are identified to the modes generated by the cross‐field instability. The spectrum of the potential fluctuations has an index β ≃ −5.8. The observed spectrum also indicates generation of a mode by wave‐wave interaction of two modes, as well as a m = o mode stationary in the
direction.
High temperature solvent growth of orthoenstatite, MgSiO3, in air
Authors: Ito Jun
Published: February 2008

Precise interlaboratory measurements of various physical properties of synthetic crystals of major mantle minerals will contribute to solving current controversies in solid earth geophysics. For this purpose, high quality crystals of orthoenstatite, MgSiO3, up to 5×2×1 mm size, were obtained by the primary crystallization of a melt in the system MgO‐SiO2‐lithiumvanadomolybdate. The growth was effected by slow cooling of the melt from 930°C to 650°C at 1.5° per hour. The temperature coefficient of solubility of MgSiO3 in this solvent is 0.023 (6.5wt%/280°C). The crystals are stoichiometric, transparent, and often euhedral, elongated parallel to c without parting or cleavage. Unit‐cell dimensions are a=18.212(4), b=8. 818(2), c=5.177(2) Å with space group Pbca. Superheating of the melt before cooling induced metastable nucleation and growth of protoenstatite which readily transformed to clinoenstatite on cooling, while rapid cooling of the melt resulted in metastable forsterites, Mg2SiO4.
Correction [to “Demonstration of 26Mg excess in Allende and evidence for 26Al”]
Authors: Lee Typhoon , Papanastassiou D. A. , Wasserburg G. J.
Published: February 2008

The first two paragraphs of this paper were omitted from the January 1976 issue due to an oversight by the AGU Office.

We report the discovery of a large anomaly in the isotopic composition of Mg in a Ca‐Al rich chondrule from the Allende meteorite. This anomaly is manifest independently of instrumental fractionation and is due to an enrichment of about 1.3 percent in 26Mg while the abundances of 25Mg and 24Mg are terrestrial in value. There is a strong correlation in this chondrule between the 26Mg excess and the Al/Mg ratio so that the most plausible cause of the anomaly is the in situ decay of now extinct 26Al (τ½ = 0.72 × 106 yr). Mineral phases extracted from a Ca‐Al‐rich aggregate have distinct Al/Mg but show identical, small Mg anomalies which are apparent after correction for fractionation (δ26Mg = 0.3%). These data indicate that this aggregate was isotopically homogenized in a high Al/Mg environment after the decay of 26Al had occurred or that some of the Mg anomalies are due to effects other than in situ decay of 26Al.
Temperature of the atmosphere of Jupiter from Pioneer 10/11 radio occultations
Authors: Kliore Arvydas J. , Woiceshyn Peter M. , Hubbard William B.
Published: February 2008

Radio occultation data from the flybys of Pioneer 10 and 11 have been analyzed using a technique which accounts for the oblateness of Jupiter's atmosphere. The center of refraction is located by the radius of curvature and the normal at the closest approach point of the ray. An Abelian inversion of the data is then carried out holding the center of refraction fixed at some average value for each occultation event. Applying this approximate theory, for the three measurements described herein, the results are consistent, showing a temperature inversion between the 10 and 100 mb levels, with temperatures between 130 and 170° K at the 10 mb level and 80 to 120° K at 100 mb. These results are also in agreement with models for the temperature in the Jovian atmosphere derived from Pioneer 10 infrared radiometer data as well as those constructed from radiative‐convective balance calculations. Nevertheless, all results derived from radio occultation measurements of Jupiter are ultimately limited in their validity at the highest pressures by a lack of detailed knowledge of the shape of isobaric contours in Jupiter's atmosphere.
Characteristics of fresh Martian craters as a function of diameter: Comparison with the Moon and Mercury
Authors: Cintala Mark J. , Head James W. , Mutch Thomas A.
Published: February 2008

Martian craters defined as fresh on the basis of morphologic parameters have been analyzed for the presence and abundance of various morphologic features as a function of size. Bowl‐shaped craters dominate the fresh crater population below about 15 km. The onset of central peaks occurs at about 5 km. Craters above about 15 km often have terraced walls, central peaks, and hummocky floors; at diameters of 40 km and greater, these features dominate fresh martian crater morphology. Central peak onset occurs at smaller diameters on Mars and the Moon than on Mercury, and terrace onset occurs at similar diameters on the Moon and Mars, but at larger diameters than on Mercury. Since Mars and Mercury have a similar surface gravitational acceleration (greater than twice that of the Moon), gravity‐controlled crater features should appear at similar diameters on the two planets. However, the differences in onset and abundances of central peaks and terraces on Mars and Mercury indicate that processes other than gravitational effects may also be important.
Observations of a high‐energy ion shock spike in interplanetary space
Authors: Sarris E. T. , Krimigis S. M. , Armstrong T. P.
Published: February 2008

The first observations of a high energy ion shock spike extending in energy to > 25 MeV for protons, > 4.3 MeV/nuc for alpha particles, and > 1.6 MeV/nuc for medium nuclei with Z ≥ 6 are reported. The measurements were obtained in the course of a solar particle event on September 15, 1974 by The Johns Hopkins University/Applied Physics Laboratory (JHU/APL) experiments on the IMP‐7 and IMP‐8 spacecraft. It is shown that the observations can be reasonably accounted for by intensive acceleration of charged particles at an "almost" perpendicular interplanetary shock wave. The data are inconsistent with a one‐step d.c.‐type acceleration process.
The absolute concentration of OH(X²π) in the Earth's stratosphere
Authors: Anderson J. G.
Published: February 2008

A technique previously used to determine the concentration of O(³P) in the stratosphere is employed to determine the absolute concentration of ground state hydroxyl radicals between 29 and 43 kilometers in the earth's atmosphere. The results from two flights of the instrument, which detects OH by molecular resonance fluorescence while descending through the stratosphere suspended from a stabilized parachute platform, are reported. Both experiments were launched on a balloon from Palestine, Texas, 32°N around noon and dropped the same afternoon near the stratopause at a solar zenith angle of 80°.

From the first flight on 18 July 1975 the OH concentration is reported to be 2.0−1.0+1.5 × 107 cm−3 at 40 kilometers and from the second on 12 January 1976 the density is found to decrease from 2.8 × 107 cm−3 at 43 kilometers to 4.5 × 106 cm−3 at 30 kilometers with an experimental uncertainty of ±35 percent.
Upper limits on atmospheric ozone reductions following increased application of fixed nitrogen to the soil
Authors: Crutzen Paul J.
Published: February 2008

Our understanding of the marine and terrestrial nitrogen budgets is severely limited. For instance, atmospheric data indicate a residence time of N2O in the atmosphere of about 10 years and consequently sources and sinks of atmospheric N2O of the order of 130×106 ton N/year. Such large sources and especially sinks for atmospheric N2O have not been satisfactorily identified and it may not be excluded, a priori, that not only the N2O source, but also its sink is affected by man. The limited knowledge about the earth's N2O budget so far obtained is in favor of the view that there is no imminent danger of large ozone reductions following the predicted increase in the input of fixed nitrogen in the soil by the year 2000. However, it seems likely that, with unchanged agricultural practices, there will develop serious long term problems, certainly in a world of exponential growth, and, for best action, it is essential that a well balanced, interdisciplinary research effort now be designed to increase our knowledge of all aspects of the earth's nutrient cycles.
Statistical‐band‐model analysis and integrated intensity for the 10.8µm band of CF2Cl2
Authors: Goldman A. , Bonomo F. S. , Murcray D. G.
Published: February 2008

Quantitative laboratory absorption measurements of the 10.8µm band of pure CF2Cl2 were carried out at 25°C. Absorption cells of various lengths were used in order to obtain curves of growth. Statistical‐band‐model analysis resulted in spectral band model parameters and yielded an integrated intensity of 1.48 × 10³ ± 10% (cm−2atm−1) at 25°C.
Nitrogen cycle factors contributing to N2O production from fertilizers
Authors: Sze Nien Dak , Rice Harbert
Published: February 2008

Nitrogen cycle factors contributing to N2O production and associated ozone perturbations are examined. It is pointed out that fertilizer nitrogen losses are non‐linear and increase with application rate. Losses are apportioned between rapid denitrification (∼ 1 year) and slower transfer processes of 10² to 10³ years between nitrogen reservoirs. It is concluded that different estimates of N2O production result from selecting nitrogen models with different denitrification and transfer efficiencies. A significant ozone perturbation cannot be ruled out because of uncertainties in the relative efficiency of agricultural denitrification.
The emission of occluded gas from rocks as a function of stress: Its possible use as a tool for predicting earthquakes
Authors: Giardini A. A. , Subbarayudu Gogineni V. , Melton Charles E.
Published: February 2008

Occluded gases were studied from fifteen types of rock, including igneous, metamorphic and sedimentary. The specimens were stressed to a crushing failure at room temperature under a vacuum of about 10−9 torr. The more abundant gases were H2, CH4, H2O, N2 CO, O2 and CO2. However, each rock released gas with a characteristic composition. The volume of gas released was a variable function of stress above a threshold value. The greatest rate of emission occurred over the latter 20% of the rock's ability to withstand stress. Analyses of stress‐released occluded gases (excluding water), released as a function of stress, are given for a granodiorite and a gneiss. Volumes (STP)of most gases observed prior to and upon failure of the rocks are equivalent to several hundred liters each per ton of rock. Stress‐induced emission of a widely distributed, highly mobile gas such as H2 could serve as an useful indicator of a critical stress build‐up in the earth's crust.
Measurements of stratospheric halocarbon distributions using infrared techniques
Authors: Williams Walter J. , Kosters John J. , Goldman Aaron , Murcray David G.
Published: February 2008

Absorption bands of CF2Cl2, CFCl3 and CCl4 have been observed in infrared sunset solar spectra in the 800‐1000 cm−1 region from 30 km altitude during a balloon flight made in September 1975. The infrared absorption bands were used to derive the distribution of these constituents in the upper troposphere and lower stratosphere. The results are compared with 1968 data and with current results of other authors.
The direct measurement of nitric oxide concentration in the upper atmosphere by a rocket‐borne chemiluminescent detector
Authors: Mason Conrad J. , Horvath Jack J.
Published: February 2008

Direct measurements of the nitric oxide concentration between 42 km and 60 km have been made with a rocket‐borne chemiluminescent detector. The first flight of this instrument was primarily a demonstration of feasibility; some instrument parameters were not measured but, instead, calculated assuming a standard atmosphere (USSA 1962) and a known vehicle velocity profile. The rocket was fired from Wallops Island, Virginia on 8 April, 1975 at 1405 LT. Our results are:

Altitude (km) Mixing Ratio NO Density (number/cc)

42 (4.2 ± 2.3)× 10−9 (2.6 ± 1.4)× 10845 (3.6 ± 2.0)× 10−9 (1.5 ± 0.9)× 10850 (2.2 ± 1.4)× 10−9 (4.6 ± 2.9)× 10755 (2.5 ± 1.6)× 10−9 (3.1 ± 1.9)× 10760 (5.2 ± 2.9)× 10−9 (3.4 ± 1.9)× 107

Corrections to the data have been made to account for an ozone‐generated background emission that set a lower limit of detectability of about lppb. Since the background emission was not measured during the flight but, instead, simulated in the laboratory, we regard these results as being upper limits on the NO concentration that prevailed at that particular time and location.
altitude of pulsating aurora determined by a new instrumental technique
Authors: Brown N. B. , Davis T. N. , Hallinan T. J. , Stenbaek‐Nielsen H. C.
Published: February 2008

Measurements of the altitude of auroral lower borders using instrumentation having high spatial and temporal resolution yields the result that the average heights of pulsating auroras are lower than previous measurements indicate. Primary electric energy in the range 10 kev to 60 kev is required to explain the results.
Palus Somni: Anomalies in the correlation of Al/Si X‐ray fluorescence intensity ratios and broad‐spectrum visible albebos
Authors: Clark P. E. , Andre C. G. , Adler I. , Podwysocki M. , Weidner J.
Published: February 2008

The positive correlation between Al/Si X‐ray fluorescence intensity ratios determined during the Apollo 15 lunar mission and a broad‐spectrum visible albedo of the moon is quantitatively established. Linear regression analysis performed on 246 1° geographic cells of X‐ray fluorescence intensity and visible albedo data points produced a statistically significant correlation coefficient of .78. Three distinct distributions of data were identified as 1) within one standard deviation of the regression line, 2) greater than one standard deviation below the line, and 3) greater than one standard deviation above above the line. The latter two distributions of data were found to occupy distinct geographic areas in the Palus Somni region. It is proposed that dark material deposited southwest of Palus Somni probably caused the anomalous distribution of data greater than one standard deviation below the regression line, and that bright material recently deposited northeast of Palus Somni probably caused the distribution of data greater than one standard deviation above the regression line.
Mercury and Mars: The role of ionospheric conductivity in the acceleration of magnetospheric particles
Authors: Hill T. W. , Dessler A. J. , Wolf R. A.
Published: February 2008

Although Mercury and Mars appear to have magnetospheres of comparable size, Mercury's magnetosphere accelerates charged particles, whereas Mars' magnetosphere apparently does not. We propose that this difference results from the fact that rapid steady‐state convection, and the associated particle acceleration, cannot occur in a Martian magnetosphere because of its connection to a highly conducting ionosphere. Mercury, which has no conducting ionosphere and probably an insufficiently conducting surface, can exhibit rapid solar‐wind‐induced convection and hence particle acceleration in its magnetospheric tail.
OH ‐ Radicals in the lower troposphere
Authors: Perner D. , Ehhalt D. H. , Pätz H. W. , Platt U. , Röth E. P. , Volz A.
Published: February 2008

OH has been detected in the lower troposphere by optical absorption of the Q1 2 (A²Σ+, v = O, X²Π, v = O) line at 307.995 nm along a 7.8 km path above Jülich (51° North, 6° East). The detection limit depended on the quality of the photographic exposure and reached 2 · 106 cm−3 in the most favourable cases.

OH generally remained below 4 · 106 cm−3, the average detection limit. But on several occasions during the observation period from mid August to November 1975 concentrations up to 7 · 106 cm−3 were observed.
dynamic unloading in shock compressed feldspar
Authors: Grady D. E. , Murri W. J.
Published: February 2008

Unloading data for a perthitic feldspar from shock compressed states between 250 and 500 kilobars are reported. Continuous stress wave profiles were measured with manganin transducers and the appropriate Riemann invariant integrated to determine the stress‐volume states during unloading. The results are in agreement with data obtained on other silicate minerals. A physical mechanism based on thermal heterogeneity and partial transformation to the high coordination phase (hollandite structure) incurred during dynamic compression provides a consistent explanation for the observed stress‐volume behavior.
Atlantic water on the Chukchi Shelf
Authors: Bourke R. H. , Paquette R. G.
Published: February 2008

An anomalously warm saline layer in the bottom of the shallow Chukchi Sea in August 1975 is believed due to a surge which drove water from the Atlantic Layer of the Arctic Ocean up onto the shelf. Two earlier occurrences of this kind of water in the Chukchi Sea have been identified in historical data.
A relationship between atmospheric carbon dioxide and Pacific sea surface temperature
Authors: Newell Reginald E. , Weare Bryan C.
Published: February 2008

There is a spatial and a temporal correspondence between changes in Pacific sea surface temperature and changes in atmospheric carbon dioxide, after seasonal trends have been removed.
Possible evidence for large, transient electric fields in the magnetotail from oppositely directed anisotropies of energetic protons and electrons
Authors: Kirsch E. , Krimigis S. M. , Sarris E. T. , Lepping R. P. , Armstrong T. P.
Published: February 2008

Observations of energetic (Ep ≳ 0.29 MeV, Ee ≳ 0.22 MeV) proton and electron bursts in the magnetotail obtained with The Johns Hopkins University Applied Physics Laboratory (JHU/APL) detectors on the earth‐orbiting (∼ 40 Re × 22 Re) IMP‐8 satellite during the magnetically disturbed day of November 26, 1973 are presented. Two periods are selected (1100 to 1130 UT, and 1230 to 1300 UT) during which intensification of the auroral electrojet was seen and large fluxes of both electrons and protons appeared at the location of IMP‐8 (XSM ≃ −26 Re; YSM ≃ 17.8 Re; ZSM ; 1.7 Re). In both cases electrons and protons exhibit large anisotropies (∼ 30:1 and 5:1 for protons and electrons, respectively), with the electrons propagating tailward while the protons are propagating earthward. These oppositely directed anisotropies last as long as one minute, and are not necessarily aligned with the local magnetic field. While these enhanced fluxes are observed, there exist significant depressions (ΔB ≈ 15 γ) in the local magnetic field accompanied with the appearance of both positive and negative components of BX and BZ, i.e., a signature of the presence of the neutral sheet. We interpret these observations as suggesting the presence of an electric field in association with the acceleration region in the magnetotail. The associated spectral and species measurements are presented and discussed in the context of proposed acceleration models.
Direct measurements of stratospheric fluoride
Authors: Mroz E. J. , Lazrus A. L. , Bonelli J. E.
Published: February 2008

The first direct measurements of stratospheric fluoride mass mixing ratios from 15 km to 40 km are given. Measurements were made during each season in 1976 and an annual average is presented.
High pressure NaAlSiO4: The first silicate calcium ferrite isotype
Authors: Liu Lin‐gun
Published: February 2008

Nepheline (NaAlSiO4)has been transformed at about 1000° C and pressures greater than 180 kbar to a new phase possessing the calcium ferrite structure in a diamond‐anvil press employing YAG laser heating. The unit‐cell dimensions of the high‐pressure phase at STP are ao = 8.740 ± 0.007, bo = 2.746 ± 0.002, Co = 10.206 ± 0.008 Å for indexing as space group Pnma with Z=4. The zero‐pressure volume change associated with nepheline → calcium ferrite structure is −31.9%, and that with Jadeite + α‐NaAlO2 (the intermediate phase assemblage) → calcium ferrite structure is −11.9%. The calcium ferrite‐type NaAlSiO4 is the first example of a silicate with this structure and is thus the most closely packed A2SiO4 compound. Mg2SiO4 may possibly adopt this structure in the earth's mantle, but in any case the new phase is the most likely host for sodium in the earth's lower mantle.
Rocketborne measurement of mesospheric H2O in the auroral zone
Authors: Rogers James W. , Stair A. T. , Degges Thomas C. , Wyatt Clair L. , Baker Doran J.
Published: February 2008

Infrared emission spectra of the long‐wavelength wing of the 6.3 µm water band between 6.7 and 7.6 µm have been measured in the mesosphere using a cryogenic rocketborne spectrometer. The resulting zenith radiance profile has been compared with a high altitude radiance model resulting in a volume mixing ratio of 3.5 ± 2.2 ppm between 49 and 70 km.
Evidence for the control of Pc 3,4 magnetic pulsations by the solar wind velocity
Authors: Singer H. J. , Russell C. T. , Kivelson M. G. , Greenstadt E. W. , Olson J. V.
Published: February 2008

The amplitude of Pc 3,4 magnetic pulsations at Calgary is shown to increase as the solar wind velocity increases. The pulsation amplitude dependence on solar wind velocity can be understood in terms of the Kelvin‐Helmholtz instability at the magnetopause boundary.
An empirical equation for the austral auroral oval
Authors: Thomas I. L. , Bond F. R.
Published: February 2008

An equation is advanced through which the co‐latitude of the austral auroral oval maximum probability contour may be found, given a specific magnetic local time and Kp index.
Nonlinear theory of the collisional Rayleigh‐Taylor instability in equatorial spread F
Authors: Chaturvedi P. K. , Ossakow S. L.
Published: February 2008

The nonlinear behavior of the collisional Rayleigh‐Taylor instability is studied in equatorial Spread F by including a dominant two‐dimensional nonlinearity. It is found that on account of this nonlinearity the instability saturates by generating damped higher spatial harmonics. The saturated power spectrum for the density fluctuations is discussed. A comparison between experimental observations and theory is presented.
Longitudinal control of Jovian magnetopause motion
Authors: Dessler A. J.
Published: February 2008

The magnetopause crossings of the Pioneer 10 and 11 spacecraft in Jovian magnetic coordinates (system III) are largely restricted in longitude to one hemisphere of Jupiter. This hemisphere is the one that has been identified by Vasyliunas [1975] as the "active hemisphere". This finding is interpreted as indicating that the magnetopause of the active hemisphere moves inward and outward with a radial speed that is typically faster than that of the inactive hemisphere.
The primordial magnetic field preserved in chondrules of the Allende meteorite
Authors: Lanoix M. , Strangway D. W. , Pearce G. W.
Published: February 2008

We have studied individual chondrules from the Allende meteorite in an effort to determine the ancient magnetic field present when the chondrules formed. An unusual magnetic property of iron‐rich metal at 130°C has made it difficult to use low temperatures for paleointensity studies on samples of the whole Allende meteorite. Furthermore, an unusual property at about 300°C (probably due to troilite which becomes antiferro‐magnetic at about 320°C) makes it difficult to determine paleointensities below the temperature. Nevertheless, between 350°C and 550°C, several chondrules from the Allende meteorite behave very well and give ancient field values as high as 16 oersteds. It is possible that this reflects the field present in the early solar nebula when the chondrules formed shortly before the Allende meteorite itself was formed.
The magnetic field of Mars: Mars 3 evidence reexamined
Authors: Russell C. T.
Published: February 2008

Published reports permit the reconstruction of the Mars 3 trajectory on which the discovery of the Martian magnetic field by Dolginov and co‐workers is based. Use of this trajectory to transform the original measurements and display them in geophysically oriented coordinate systems leads to the conclusion that the observed magnetic field was draped over the Martian obstacle as expected if the field were simply shocked and compressed solar wind magnetic field. There is no conclusive evidence that Mars 3 ever entered a Martian magnetosphere.
Mineralogical contraints on Curie isotherms in deep crustal magnetic anomalies
Authors: Haggerty Stephen E.
Published: February 2008

Ferrimagnetic minerals above their respective Curie temperatures are paramagnetic. Deep crustal magnetic anomalies are constrained, therefore, to a depth detection limit which is defined by the Curie isotherm. Although magnetite, with a Curie temperature of 580°C, is widely employed to map Curie isothermal surfaces it is a relatively rare mineral as stoichiometric Fe3O4. Solid solution of magnetite towards antiferromagnetic ulvöspinel (Fe2TiO4) reduces the Curie temperature to a minimum of −153°C and a high order of ferrimagnetic behavior can only be accomplished in plutonic rocks under the most exacting conditions of equilibrium exsolution and oxidation. Magnetic anomaly models need not be constrained by the 580°C limit because the range in temperatures may vary between 300°C if maghemite (αFe2O3)dominates and 680°C if hematite (γFe2O3) is dominant. Because many magnetic anomaly interpretations require Curie isothermal depths in excess of 580°C, and because these may extend to the lower crust‐upper mantle boundary, it is proposed that these anomalies may arise from partially serpentinized ultramafic bodies which have metal alloys as the prime magnetic source material with Curie temperatures in the range 620°‐1100°C.
Electrostatic hydrogen cyclotron waves near one Earth radius altitude in the polar magnetosphere
Authors: Kintner P. M. , Kelley M. C. , Mozer F. S.
Published: February 2008

The wave plasma experiment onboard satellite S3‐3 has detected electrostatic hydrogen cyclotron waves at altitudes near 1RE in the Earth’s polar magnetosphere. The observed wave properties are in excellent agreement with the theoretical dispersion relation as well as the linear instability theory for current driven ion cyclotron waves and are used to determine that the plasma is more than 90% hydrogen, that the electron temperature is about 3.5 electron volts and that Te/T1 is in the range of 1 or larger. The strongest wave events are associated with large ⩾120mV/m) Dc electric fields described in an earlier paper (Mozer et al., 1977) as paired electrostatic shocks. Other wave events, which are not as clearly related to shock structures, usually are imbedded in or specifically correlate with fluxes of electrons from .074 keV to 5.04 keV and turbulent Dc electric fields. These results are consistent with a lower threshold for ion cyclotron waves than for shocks or double layers.
The roles of boundary friction, basal shear stress and deep mantle convection in plate tectonics
Authors: Davies Geoffrey F.
Published: February 2008

A set of forces on the lithospheric plates, including a driving basal shear stress, is deduced and found to be plausibly consistent with the possibility that large‐scale, whole‐mantle convection cells contribute significantly to driving the plates. Fractional and driving plate boundary forces are estimated, and a basal shear stress (BS) is assumed to complete the force balance on each plate. Boundary frictional stresses are assumed to be large (of the order of kilobars), as suggested by Hanks [1977]. All BS stresses of significant magnitude are roughly aligned with plate motions. The BS is the only available driving force for the South American and Eurasian plates, and is probably significant in driving most other plates. More generally, the results demonstrate that force models are possible which differ substantially from previous models.
The distortion of the Moon due to convection
Authors: Cassen P. , Young R. E. , Schubert G.
Published: February 2008

Numerical calculations of the dynamical ellipticity of the moon due to finite amplitude solid state convection indicate that convection could be the cause of the non‐hydrostatic gravitational figure, but only if the lunar lithosphere is capable of resisting global scale deformation. Thus lithospheric inhomogeneities and surface loads could also contribute substantially to the disequilibrium of the gravity figure. The calculations also show that it is unlikely that the geometrical distortion is due to convection.
Island arc curvature, velocity of convergence and angle of subduction
Authors: Tovish Aaron , Gerald Schubert
Published: February 2008

We report data on the curvature RC, rate of subduction vc and slab dip α for 28 convergent boundary segments of oceanic plates. Slowly converging plates (vc < 5 cm/yr) are associated with arcs having RC < 10°, while more rapidly converging plates produce arcs with RC ranging from 10° to greater than 90°. This provides a way of estimating former convergence rates of extinct arcs. Slab dip α is independent of vc for vc < 10 cm/yr; the inverse relation between α and vc proposed by Luyendyk (1970) is not substantiated by our larger data set. Slab dip and arc curvature are not correlated.
Martian cratering V: Toward an Empirical Martian Chronology, and Its Implications
Authors: Hartmann William K.
Published: February 2008

This paper estimates ages of Martian features by dividing least‐square‐fitted crater densities by an estimated Martian crater production rate. This method is more rigorous than methods based purely on assumptions about correspondence of lunar and Martian cratering rates. Results are interpreted as supporting the conclusion of Burns et al. (in press) that Mars shifted climatic states due to a change in obliguity caused by buildup of massive volcanics. Prior to a few gy. ago, conditions favored erosion, deposition, and fluvial channel formation. Recent volcanics postdate this era, and the surfaces of the major shields are fairly well constrained in age to a few hundred my, in agreement with Masursky et al.
A simple method for approximating the annual temperature of the northern hemisphere
Authors: Landsberg H. E. , Groveman B. S. , Hakkarinen I. M.
Published: February 2008

Using annual temperature values for only nine northern hemisphere stations, in the latitude belt from 43° to 67°N, an estimate can be quickly obtained for the departure of hemispheric temperature from its average. A multiple correlation coefficient between this independent variable and the station values of 0.81 accounts for nearly two thirds of the variance. In the 77‐year interval 1899‐1975 the regression equation gave values with the correct sign of departure in 68 years, or 88 per cent of the cases.
Indication of gravity wave‐meanflow interaction in upper atmospheric radar observations
Authors: Klostermeyer J. , Liu C. H.
Published: February 2008

Acoustic‐gravity waves detected by the Jicamarca VHF radar at tropospheric and stratospheric heights have properties that cannot be explained by simple theoretical models. The sign of the vertical wavenumber, in particular, reverses in a region with considerable background wind shear indicating wave‐wind interaction in a critical layer. A model is analyzed in which a gravity wave propagates into a critical layer with small Richardson number so that near total reflection and strong transmission take place due to the extraction of momentum and energy from the mean flow. Solutions of the linearized hydrodynamic equations describing gravity wave propagation in a viscid compressible atmosphere with shear flow show that this model is consistent with the observed data.