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On the measurement of atmospheric extinction of solar radiation and the sun's aureole
Atmosphere to Solar Radiation", Applied Optics, Sept. 1963, Vol. 2, No. 9, 12 pp., Illus. The paper reports measurements of atmospheric absorption coefficients obtained from solar observations with a prism instrument. The atmospheric attenuation for infrared solar radiation wavelengths passing through a clear sky is of two types: (a) Selective absorption by the polyatomic gaseous constituents of the atmosphere; and (b) continuum attenuation due to scattering and absorption by particulate m a t t e r and water droplets suspended in the atmosphere, and the integrated absorption effect of the wings of the multitude of absorption lines which are distributed throughout the spectrum. The selective absorption is characterized by many thousands of absorption lines forming the absorption bands due to the various molecules. With a very high-resolution spectrometer it is possible to observe these individual lines and to deduce the frequency dependence of the atmospheric absorption coefficients with a detail commensurate with the observed line structure. For many applications, such detail is unnecessarily complex and it is sufficient to obtain absorption coefficients for the gross band structure as deduced from data obtained by means of lower resolution prism spectrometers. In this case it is necessary that the bandpass of the spectrometer be large compared with the width and spacing of single rotation lines and small compared to the width of an entire absorption band. The present paper is an extension of the earlier one to cover the atmospheric infrared spectrum throughout the wave-length range 1.0 to 12.5~.
Karapiperis, P. P., University of Athens, "Interdiurnal Variability of Total Solar and Sky Radiation on a Horizontal Surface at Athens, Greece", COMPLES, Bulletin, 5, Nov. 1963, 4 pp. This paper refers to the difference between the total solar and sky radiation measured for the same hours in consecutive days and the integrated daily total solar and sky radiation in consecutive days during the months of January, April, July and October which are the most representative months of the four seasons. The lower and higher average values of the variability occur respectively with low and high position of the sun during the day. Owing to small changes in the amount of cloudiness from one day to the next in July, the minimum diurnal range occurs in this summer month. The maximum diurnal range is observed in April and this behavior is due to the seasonal height of the sun and to alternation of air masses. The average hourly values of risings (increasing radiation) and fallings (decreasing radiation) are closely correlated for all the months under consideration.
Robinson, N., and L. Stoch, "Sky Radiation Measurement and Corrections", COMPLES, Bulletin, 5, Nov. 1963, 12 pp. Formulae for the correction for any time of the year, caused by the obstruction of part of the sky by the shading frame, (described in Sec. I I hereof) are derived. Correction tables are compiled and are also represented graphically. With the aid of these tables, the sky radiation, as recorded by the apparatus described in Sec. II, should be corrected, thereby standardizing the measured radiation and permitting unbiased comparison of the sky radiation for different regions.
Masterson, John E., Sidney Teweles, and William Nordberg, "Meteorological Observations Above 30 Kilometers", Part of the Proceedings on Conference on Meteorological Support for Aerospace Testing and Operation, NASA SP-49, 1964, 57 pp. This report consists of three papers. The first by Masterson discusses the small solid propellant sounding rocket systems which have been used to measure the atmospheric structure from 30-60 kin. The second by Teweles is a comprehensive survey of the meterology of the 30 to 60 km. region based on the sounding rocket observations. The third by Nordberg Vol. 9, No. 1, 1965
carries the discussion to the vicinity of 90 km. covering the engineering and meterological aspects of the sounding rocket observations which employ the two-stage solid propellant rocket systems.
Detwiler, C. R., J. D. Purcell, and R. Tousey, U. S. Naval Research Laboratory, "The Extreme Ultraviolet Spectrum of the Sun", Mdmoires Soc. R. Sc. Liege, 1960, 17 pp., Illus. A report on the several great advances in the exploration of the extreme ultraviolet spectrum of the sun during the years 1959 and 1960.
Psarouthakis, John, Martin Marietta Corporation, "Apparent Thermal Emissivity from Surfaces with Multiple V-Shaped Grooves", AIA A Journal, Vol. 1, No. 8, Aug. 1963, 4 pp. A requirement of the advancement in space and high-temperature technology is the transfer of heat by thermal radiation. The efficient transfer of heat by radiation can be accomplished by surfaces of high thermal emissivity. Such surfaces are difficult to obtain, particularly at very high temperatures. This paper presents certain experimental and analytical results on metallic surfaces with multiple V-shaped grooves. The radiant interchange within an infinitely long V-shaped groove is studied, and its apparent thermal emissivity is found as a function of the included angle and the emissivity of the surfaces including the angle. The view factor and the apparent emissivity are plotted for various angles vs the surface emissivity. The experimental results for a 30 ° included angle are in agreement with the analysis. It is found that, with an included angle of 30 ° and surface emissivity of 0.3, an apparent emissivity of 0.64 can be obtained. Experimental measurements of the total thermal emissivity of a ground molybdenum surface at various temperatures also are presented. A discussion on actual application of grooves on radiating surfaces and the effects of imperfections present in the grooves due to cutting processes is given.
Sekihara, K., and K. Mural, Meteorological Research Institute, Tokyo, "On the Measurement of Atmospheric Extinction of Solar Radiation and the Sun's Aureole", March 1961, 18 pp. A new type of spectrophotometer is designed for the measurement of the angular distribution of sky radiation in a monochromatic range and also for that of spectral distribution of direct solar radiation. Using this instrument the spectral intensities of direct sunlight and those of the sun's aureole as far as 10 degrees with an interval of one degree for various altitudes of the sun were measured. On the basis of the results of observation the spectral distribution of sky radiation were considered. As regards the spectral distribution of extinction coefficient observed curves showed two regions of different tendencies, namely a steep rising toward the shorter wave-length in the blue and ultra-violet region and a comparatively fiat tendency in the yellow and red region.The anomalous transmission in the near ultra-violet which was discussed by Deirmendjian and Sekera (1956) could not be found according to this observation. One of the observed characteristics of the angular distribution of sky radiation is the tendency in the ultra-violet region at a very low sun elevation, where the sign of the gradient is reversed as compared with the other wave-lengths. This tendency was explained by calculation as the effect of multiple scattering. As to the effect of dust particles, a preliminary analysis was done using the results of calculations of Deirmendjian (1957) and those of Bullrich (1952) concerning, respectively, the measurement of extinction coefficients and that of aureole. Marked deviation from the inverse fourth power law seems to exist concerning the size distribution of dust particles as far as the preliminary results are concerned.
XIV--Geophysical and Meteorological: Weather, 71
Karapiperis, P. P., University of Athens, "Interdiurnal Variability of Total Solar and Sky Radiation on a Horizontal Surface at Athens, Greece", COMPLES, Bulletin, 5, Nov. 1963, 4 pp. This paper refers to the difference between the total solar and sky radiation measured for the same hours in consecutive days and the integrated daily total solar and sky radiation in consecutive days during the months of January, April, July and October which are the most representative months of the four seasons. The lower and higher average values of the variability occur respectively with low and high position of the sun during the day. Owing to small changes in the amount of cloudiness from one day to the next in July, the minimum diurnal range occurs in this summer month. The maximum diurnal range is observed in April and this behavior is due to the seasonal height of the sun and to alternation of air masses. The average hourly values of risings (increasing radiation) and fallings (decreasing radiation) are closely correlated for all the months under consideration.
Robinson, N., and L. Stoch, "Sky Radiation Measurement and Corrections", COMPLES, Bulletin, 5, Nov. 1963, 12 pp. Formulae for the correction for any time of the year, caused by the obstruction of part of the sky by the shading frame, (described in Sec. I I hereof) are derived. Correction tables are compiled and are also represented graphically. With the aid of these tables, the sky radiation, as recorded by the apparatus described in Sec. II, should be corrected, thereby standardizing the measured radiation and permitting unbiased comparison of the sky radiation for different regions.
Masterson, John E., Sidney Teweles, and William Nordberg, "Meteorological Observations Above 30 Kilometers", Part of the Proceedings on Conference on Meteorological Support for Aerospace Testing and Operation, NASA SP-49, 1964, 57 pp. This report consists of three papers. The first by Masterson discusses the small solid propellant sounding rocket systems which have been used to measure the atmospheric structure from 30-60 kin. The second by Teweles is a comprehensive survey of the meterology of the 30 to 60 km. region based on the sounding rocket observations. The third by Nordberg Vol. 9, No. 1, 1965
carries the discussion to the vicinity of 90 km. covering the engineering and meterological aspects of the sounding rocket observations which employ the two-stage solid propellant rocket systems.
Detwiler, C. R., J. D. Purcell, and R. Tousey, U. S. Naval Research Laboratory, "The Extreme Ultraviolet Spectrum of the Sun", Mdmoires Soc. R. Sc. Liege, 1960, 17 pp., Illus. A report on the several great advances in the exploration of the extreme ultraviolet spectrum of the sun during the years 1959 and 1960.
Psarouthakis, John, Martin Marietta Corporation, "Apparent Thermal Emissivity from Surfaces with Multiple V-Shaped Grooves", AIA A Journal, Vol. 1, No. 8, Aug. 1963, 4 pp. A requirement of the advancement in space and high-temperature technology is the transfer of heat by thermal radiation. The efficient transfer of heat by radiation can be accomplished by surfaces of high thermal emissivity. Such surfaces are difficult to obtain, particularly at very high temperatures. This paper presents certain experimental and analytical results on metallic surfaces with multiple V-shaped grooves. The radiant interchange within an infinitely long V-shaped groove is studied, and its apparent thermal emissivity is found as a function of the included angle and the emissivity of the surfaces including the angle. The view factor and the apparent emissivity are plotted for various angles vs the surface emissivity. The experimental results for a 30 ° included angle are in agreement with the analysis. It is found that, with an included angle of 30 ° and surface emissivity of 0.3, an apparent emissivity of 0.64 can be obtained. Experimental measurements of the total thermal emissivity of a ground molybdenum surface at various temperatures also are presented. A discussion on actual application of grooves on radiating surfaces and the effects of imperfections present in the grooves due to cutting processes is given.
Sekihara, K., and K. Mural, Meteorological Research Institute, Tokyo, "On the Measurement of Atmospheric Extinction of Solar Radiation and the Sun's Aureole", March 1961, 18 pp. A new type of spectrophotometer is designed for the measurement of the angular distribution of sky radiation in a monochromatic range and also for that of spectral distribution of direct solar radiation. Using this instrument the spectral intensities of direct sunlight and those of the sun's aureole as far as 10 degrees with an interval of one degree for various altitudes of the sun were measured. On the basis of the results of observation the spectral distribution of sky radiation were considered. As regards the spectral distribution of extinction coefficient observed curves showed two regions of different tendencies, namely a steep rising toward the shorter wave-length in the blue and ultra-violet region and a comparatively fiat tendency in the yellow and red region.The anomalous transmission in the near ultra-violet which was discussed by Deirmendjian and Sekera (1956) could not be found according to this observation. One of the observed characteristics of the angular distribution of sky radiation is the tendency in the ultra-violet region at a very low sun elevation, where the sign of the gradient is reversed as compared with the other wave-lengths. This tendency was explained by calculation as the effect of multiple scattering. As to the effect of dust particles, a preliminary analysis was done using the results of calculations of Deirmendjian (1957) and those of Bullrich (1952) concerning, respectively, the measurement of extinction coefficients and that of aureole. Marked deviation from the inverse fourth power law seems to exist concerning the size distribution of dust particles as far as the preliminary results are concerned.
XIV--Geophysical and Meteorological: Weather, 71