共查询到20条相似文献,搜索用时 31 毫秒
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Lorenzo Casertano 《Pure and Applied Geophysics》1956,33(1):177-186
Riassunto Si analizzano andamenti sperimentali della luminosità del cielo nelle zone rossa e bleu dello spettro. Dal confronto con diversi
andamenti teorici si ottiene la spiegazione per la diversità di comportamento della luminosità nelle due zone considerate,
e si riconosce la possibilità che — sotto certe condizioni — è consentito tener conto della sola diffusione primaria. Considerando
anche la diffusione non molecolare si indica un metodo per calcolare, dalle misure di luminosità, il valore di un parametro
che rappresenta un indice del contenuto di polveri nell’atmosfera. Si discutono alcuni valori trovati in base a misure eseguite
all’Osservatorio Vesuviano.
Prof.Lorenzo Casertano, Osservatorio Vesuviano,Resina (Napoli) 相似文献
Summary Experimental outlines of sky brightness in the red and blue fields of spectrum are analized. From comparison with theoretical predictions one desumes the explanation about the different behaviour of brightness in the two considered fields and possibility — under certain conditions — of taking account only primary scattering. Considering also non-molecular scattering a method is shown to deduce, from the measurements of intensities of sky radiation, the value of a parameter representing the content of dust into atmosphere. Some experimental values found in measurements made at the ? Osservatorio Vesuviano ? are discussed.
Prof.Lorenzo Casertano, Osservatorio Vesuviano,Resina (Napoli) 相似文献
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Catherine Constable 《Surveys in Geophysics》2016,37(1):27-45
The natural spectrum of electromagnetic variations surrounding Earth extends across an enormous frequency range and is controlled by diverse physical processes. Electromagnetic (EM) induction studies make use of external field variations with frequencies ranging from the solar cycle which has been used for geomagnetic depth sounding through the 10\(^{-4}\)–10\(^4\) Hz frequency band widely used for magnetotelluric and audio-magnetotelluric studies. Above 10\(^4\) Hz, the EM spectrum is dominated by man-made signals. This review emphasizes electromagnetic sources at \(\sim\)1 Hz and higher, describing major differences in physical origin and structure of short- and long-period signals. The essential role of Earth’s internal magnetic field in defining the magnetosphere through its interactions with the solar wind and interplanetary magnetic field is briefly outlined. At its lower boundary, the magnetosphere is engaged in two-way interactions with the underlying ionosphere and neutral atmosphere. Extremely low-frequency (3 Hz–3 kHz) electromagnetic signals are generated in the form of sferics, lightning, and whistlers which can extend to frequencies as high as the VLF range (3–30 kHz).The roughly spherical dielectric cavity bounded by the ground and the ionosphere produces the Schumann resonance at around 8 Hz and its harmonics. A transverse resonance also occurs at 1.7–2.0 kHz arising from reflection off the variable height lower boundary of the ionosphere and exhibiting line splitting due to three-dimensional structure. Ground and satellite observations are discussed in the light of their contributions to understanding the global electric circuit and for EM induction studies. 相似文献
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Jinhai Yu 《中国科学D辑(英文版)》1997,40(3):322-328
The following Poisson’s equation with the Stokes’ boundary condition is dealt with $$\left\{ \begin{gathered} \nabla ^2 T = - 4\pi Gp outside S, \hfill \\ \left. {\frac{{\partial T}}{{\partial h}} = \frac{1}{\gamma }\frac{{\partial y}}{{\partial h}}T} \right|_s = - \Delta g, \hfill \\ T = O\left( {r^{ - 3} } \right) at infinity, \hfill \\ \end{gathered} \right.$$ whereS is reference ellipsord. Under spherical approximation transformation, the ellipsoidal correction terms about the boundary condition, the equation and the density in the above BVP are respectively given. Therefore, the disturbing potentialT can he obtained if the magnitudes aboveO(ε4) are neglected. 相似文献
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Accumulation of salts in lakes with small catchment areas and substrate composed of magmatogene, metamorphized, and sedimentary rocks have been studied. Direct dependence of the chemical composition of salt-lake waters on that of deep-seated endogenous waters is demonstrated. Groups of salt lakes have been found to form linear rows or ellipses.Translated from Vodnye Resursy, Vol. 32, No. 1, 2005, pp. 13–17.Original Russian Text Copyright © 2005 by Dzyuba, Kulagina. 相似文献
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M. Yu. Reshetnyak 《Izvestiya Physics of the Solid Earth》2012,48(4):326-334
The eigenvalue problem for Parker’s dynamo model is considered. We study how the intensity of convection in the liquid core
of the Earth affects the generation of the geomagnetic field with different directions of latitudinal field propagation. The
scenarios of transition of the geomagnetic field from frequent to rare reversals are suggested. 相似文献
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Information included in this summary is based on more detailed reports published in the Bulletin of the Global Volcanism Network, vol. 28, no. 8, August 2003 (on the Internet at ). Edited by scientists at the Smithsonian, this Bulletin includes reports provided by a worldwide network of correspondents. The reports contain the names and contact information for all sources. Please note that these reports are preliminary and subject to change as events are studied in more detail. The Global Volcanism Program welcomes further reports of current volcanism, seismic unrest, monitoring data, and field observations. 相似文献
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Matthew D. Palmer 《Surveys in Geophysics》2012,33(3-4):351-357
Under equilibrium conditions, climate can be viewed in simple terms as the average energy pathways that incoming solar radiation takes before exiting the system in order to maintain overall energy balance. Similarly, future climate change will ultimately be determined by how the Earth’s energy balance and average energy pathways change in response to external radiative forcings, such as anthropogenic greenhouse gases, and internal redistributions. Here, we give an overview of climate research in the context of Earth’s energy flows and make the case for improved observations of total energy as a more physically robust metric of climate change than the commonly used surface temperature record. 相似文献
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Edward Venzke 《Bulletin of Volcanology》2005,67(6):599-600
Information included in this summary is based on more detailed reports published in the Bulletin of the Global Volcanism Network, v. 29, no. 9, September 2004 (on the Internet at ). Edited by scientists at the Smithsonian, this Bulletin includes reports provided by a worldwide network of correspondents. The reports contain the names and contact information for all sources. Please note that these reports are preliminary and subject to change as events are studied in more detail. The Global Volcanism Program welcomes further reports of current volcanism, seismic unrest, monitoring data, and field observations. 相似文献