摘要:

Anyone who has a bookshelf on which he keeps his issues of theJournal of Geophysical Researchknows that the volume and quality of published material have been increasing from year to year. So also have the costs of publishing it. The section of theJournal of Geophysical Researchnow devoted to the earth had become too big, and so this issue starts a new division of the Journal to produce three, instead of the former two, sections. This section of the Journal will contain papers related to the oceans and the atmosphere, another will cover the surfaces and interior of planets, and a third will cover space physics.

ISSN:0148-0227    

DOI:10.1029/JC074i013p03311

年代:1969

数据来源: WILEY

摘要:

A bulk heat‐transfer relation applicable to unstable conditions is proposed. The relation incorporates the assumptions that heat transfer near the surface is by molecular conduction, and the bulk transfer relation does not depend explicitly on the surface roughness characteristics, provided that roughness elements are not large in comparison with the thickness of the thermal boundary layer. The predicted heat flux compares favorably with heat‐transfer rates determined in the Great Plains field program and with measurements made by J. E. Vehrenkamp over a desert dry lake under conditions of extreme upward heat flux. The limiting case of very small surface stress is discussed, and the proposed formulation in this limit is compared with the heat‐transfer relation observed in laboratory experiments on parallel‐plate con

ISSN:0148-0227    

DOI:10.1029/JC074i013p03313

年代:1969

数据来源: WILEY

摘要:

Observations of sky emission and absorption in the far infrared (mean wavelength 120 μ) and, simultaneously, sky emission at wavelength 6 μ have been made by P. Kuhn (ESSA) from the NASA CV‐990 aircraft flying at 12‐km altitude over the middle Pacific at latitudes 10°–15°N. A lack of correlation between the near‐ and far‐infrared data, especially during times of visible cirrus cloud cover above the aircraft, indicates a wavelength‐dependent atmospheric phenomenon, which is interpreted as scattering. The contributions of scattering by molecules, aerosols, water drops, and ice crystals in the upper atmosphere are estimated, and it is shown that the latter water drops and ice crystals may account for the observed phenomenon. The possible influence of scattering on past high‐altitude solar observations is

ISSN:0148-0227    

DOI:10.1029/JC074i013p03322

年代:1969

数据来源: WILEY

摘要:

Laboratory reflection spectra have been obtained for very small frost particles (less than 2 μ in diameter) in the spectral range from 0.9 to 3.4 μ. These spectra differ from the spectra of large ice particles, particularly in the near‐absence of reflectivity minima near 1.5 and 2.0 μ. Clouds of these particles would exhibit a reflection spectrum in close agreement with that of the Venus clouds, despite any question of gaseous CO2absorption in the Venus atmosphere. Ice remains the best candidate for the principal constituent of Venus cl

ISSN:0148-0227    

DOI:10.1029/JC074i013p03331

年代:1969

数据来源: WILEY

摘要:

The spectral reflectivity of clouds of ice spheres is calculated for the near‐infrared wavelength region (1 ≲ λ ≲ 4 μ) for comparison with laboratory observations of ice clouds. The laboratory cloud particles were highly nonspherical ice crystals; however, it is shown that the major feature of the theoretical spectrum is in close agreement with the observations when spheres of equal volume are employed in the radiative transfer problem. The results provide some support for the contention that randomly oriented nonspherical particles may be replaced by equivalent spheres for calculations of reflected intensities. The reflectivities are shown to be sensitive to the particle size, especially the reflectivity minima near 1.5 and 2.0 μ. Changes by a factor of 2 in the particle size cause significant variations in the major reflectivity features; this result verifies that spectral reflectivity measurements can be of considerable value for cloud identification. The agreement of the theoretical and experimental spectra also indicates that it should be possible to obtain meaningful conclusions from infrared reflectivity measurements of planetary atmospheres, such as the observations that have been made on the atmosphere

ISSN:0148-0227    

DOI:10.1029/JC074i013p03337

年代:1969

数据来源: WILEY

摘要:

Measurements of radiation emitted by the atmosphere of the earth in an infrared absorption band of water vapor, obtained with satellite‐borne instrumentation, contain information on atmospheric relative humidity. Two methods are developed for estimating tropospheric relative humidity profiles from infrared spectral measurements for which the spectral resolution elements are narrow in comparison with the total width of the absorption band but wide in comparison with a single absorption line. The methods, which are essentially complementary, consist of a direct estimation technique, which requires a minimum of a priori knowledge of the behavior of the relative humidity profile, and a statistical estimation technique, which can make full use of a knowledge of the statistics of tropospheric humidities in situations where such knowledge exists. An analysis of the propagation of errors in the measured spectral intensities indicates that meaningful estimates should be obtained from the 6.3‐μ water vapor band in the presence of realistic instrumental noise for most types of atmospheres. One exception is the polar winter atmosphere, where strong error propagation occurs because of the behavior of the temperature profile. An examination of the effects on the inferred relative humidity profile of errors in the temperature profile employed in the estimation reveals that the relative humidities inferred in the lowest layers of the troposphere are extremely sensitive to errors in the surface temperature, which may prove to be the limiting factor in obtaining complete relative humidity profiles. Examples of applications of the techniques to synthetic data from model atmospheres and to real data obtained with a balloon‐borne infrared interferometer spectrometer are

ISSN:0148-0227    

DOI:10.1029/JC074i013p03347

年代:1969

数据来源: WILEY

摘要:

Atmospheric dust samples were collected on a cruise in the eastern equatorial Pacific during the spring of 1967 in the general area of 8°N to 17°S and 80°W to 110°W. The measured dust loads ranged from 0.04 to 1.2 μg/m3air, the highest concentrations occurring principally along a track between 5° and 8°N. The mineralogical composition of the samples collected north of the equator differs markedly from the more southerly samples. The northern dust contains a plagioclase as the dominant mineral and subordinate amounts of quartz; in the southerly samples, quartz is prevalent and appreciable quantities of micas, chlorites, and smectites are also present. All samples contain significant amounts of organic material. The relatively high dust loadings encountered along the northern track suggest that windborne dust may be of significance to sedimentation in large areas of the Pacific to the west of Central A

ISSN:0148-0227    

DOI:10.1029/JC074i013p03362

年代:1969

数据来源: WILEY

摘要:

The physical and chemical properties of particles collected from the eruption fume of Kilauea, Mayon, and Arenal volcanoes were determined by colorimetric chemical techniques, neutron activation, atomic absorption, X‐ray diffraction, an electron microprobe, and electron microscopy. As in previous studies, more than 95% of the Kilauea particles were largely dilute sulfuric acid droplets plus some mainly needle‐like crystals, which previously had been tentatively identified as sulfur and calcium and ammonium sulfates. The wet chemical analysis demonstrated the presence of soluble calcium, ammonium, and magnesium sulfates. Each type of particle observed at Kilauea was also observed at Mayon, but most of the droplets from Mayon were much less acidic. Some Mayon particles were ‘ash’ or minute spheres; this type of particle was not observed at Kilauea. Particles in the fume from Arenal were more like the particles from Mayon than like those from

ISSN:0148-0227    

DOI:10.1029/JC074i013p03372

年代:1969

数据来源: WILEY

摘要:

Study of the variation of intensity of the solar beam with altitude reveals a significant attenuation due to aerosol. Analysis of data obtained during three balloon flights indicates that the areosol layers are quite variable and on occasion can attenuate the direct solar radiation at altitudes in excess of 30 km.

ISSN:0148-0227    

DOI:10.1029/JC074i013p03379

年代:1969

数据来源: WILEY

摘要:

This note predicts surface temperature and heat flux variations induced by a progressive wave on a thin layer of water across which steep thermal gradients exist. It is shown that molecular conduction and convection due to the wave alone (this excludes any buoyancy induced convection) do not account for the behavior of the surface temperature that has been observed in a wave tank.

ISSN:0148-0227    

DOI:10.1029/JC074i013p03384

年代:1969

数据来源: WILEY