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1.
Shved G. M. Novikov S. S. Gavrilov N. M. 《Izvestiya Atmospheric and Oceanic Physics》2020,56(1):43-51
Izvestiya, Atmospheric and Oceanic Physics - A spatial distribution model for air density perturbations during the propagation of internal gravity waves (IGWs) is used to derive estimates for... 相似文献
2.
The near-infrared (NIR) emission of the Martian atmosphere in the CO2 bands at 4.3, 2.7, 2.0, 1.6, 1.4, 1.3, 1.2, and 1.05 µm and in the CO bands at 4.7, 2.3, 1.6, and 1.2 µm is mainly generated under nonlocal thermodynamic equilibrium (NLTE) conditions for vibrational states, the transitions from which form the specified bands. The paper presents the results of simulations of the population of these states under NLTE for daytime conditions. In the cold high-latitude troposphere, the NLTE takes place much lower than in the troposphere under typical temperature conditions. If the NIR-radiation reflection from the surface is ignored, the population of high vibrational states substantially decreases, at least, in some layer of the lower atmosphere. However, inelastic collisions of CO2 and CO molecules with O atoms produce no considerable influence on the values of populations. The population of vibrational states, the transitions from which form NIR bands, is also almost insensitive to possible large values of the quenching-in-collision rate constants of vibrational states higher than CO2(0001). However, very large errors in the estimates of the population of vibrational states of the CO2 molecule (rather than the CO molecule!) can be caused by the uncertainty in the values of the rate constant of exchange between CO2 molecules by the energy quantum of the asymmetric stretching vibrational mode. For this intermolecular exchange, we recommend a possible way to restrict the vibrational excitation degree of the molecule that is a collision partner and to maintain simultaneously a sufficiently high accuracy in the population estimate. 相似文献
3.
Advances in attacking the problem of radiative transfer in the near infrared (NIR) bands of CO2 and CO under nonlocal thermodynamic equilibrium (NLTE) conditions depend on the accuracy of taking into account the radiation processes and inelastic collisions of CO2 and CO molecules. The focus of the paper is to substantially improve the physical model of the problem and update the calculation method. It is the first time the surface albedo is introduced into the problem of the molecular emission under NLTE conditions. The values of the rate constants for inelastic molecular collisions and their temperature dependences have been radically updated. In some cases, since laboratory measurements of these constants are lacking, different versions are provided for them. The relative abundance of CO2 and CO isotopologues is based on the ratios of isotope abundances for the elements C and O obtained from the measurements in the atmosphere of Mars. The intensity of extraterrestrial solar NIR radiation is specified on the base of the high-accuracy ground-based measurements. In the method for calculating the populations of vibrational states, we pioneer in completely taking into account the overlapping of spectral lines in the NIR bands of CO2 and CO. 相似文献
4.
G. M. Shved 《Solar System Research》2016,50(2):161-164
The isotopic composition of carbon dioxide in the Martian atmosphere from the measurements of Mars Science Laboratory have been used to estimate the relative abundances of CO2 isotopologues in the Martian atmosphere. Concurrently, this study has revealed long-standing errors in the amounts of some of low-abundance CO2 isotopologues in the Earth’s atmosphere in the databases of spectroscopic parameters of gases (HITRAN, etc.). 相似文献
5.
V. P. Ogibalov A. I. Pogoreltsev I. N. Fedulina G. M. Shved 《Izvestiya Atmospheric and Oceanic Physics》2006,42(1):84-92
The effect of tidal perturbations in temperature on the rate of cooling the upper mesosphere and lower thermosphere in the
CO2 15-μm band is revised. It is shown that the effect of solar semidiurnal tide on radiative cooling can be neglected. However,
the solar diurnal tide leads to a marked increase in the rate of radiative cooling (up to a relative increase by about 0.1
to 0.2) near the equator at altitudes below 100 km. It is possible that this additional cooling is responsible for the air
descent observed in the near-equatorial thermosphere at altitudes above 105 km.
Original Russian Text ? V.P. Ogibalov, A.I. Pogoreltsev, I.N. Fedulina, G.M. Shved, 2006, published in Izvestiya AN. Fizika
Atmosfery i Okeana, 2006, Vol. 42, No. 1, pp. 92–101. 相似文献
6.
The estimates of the population of excited vibrational states of the CO2 molecule and of the rate of radiative cooling of the atmosphere in the 15-m CO2 band are given for the nighttime mesosphere and thermosphere of Mars. For the first time, these estimates are made (1) with allowance for the overlap of lines in the 15-m band; (2) for a wide set of vibrational states of seven isotopes of the CO2 molecule, which was used earlier in the solution of a similar terrestrial problem; and (3) using the rate constant for quenching of the CO2(0110) state in collisions with oxygen atoms, which has been recently measured for low temperatures by Khvorostovskaya et al. (2002). The main results are as follows. 1. The approximation of isolated lines provides a satisfactory accuracy of determining the radiative cooling rate and overestimates vibrational temperatures of the states of the 2 mode by no more than 3 K for the 12C16O2 molecule and by no more than 2 K for low-abundant isotopes of the CO2 molecule. 2. A reasonably high accuracy of estimating the cooling rate can be achieved by taking into account only fundamental vibrational transitions in 12C16O2, 13C16O2, 16O12C18O, and 16O12C17O molecules and the hot transitions 22 2 and 32 22 in the 12C16O2 molecule. 3. The vertical profile of the total rate of radiative cooling displays two peaks. The maximum near a height of 130 km is very sensitive to temperature and to the ratio of the mixture for oxygen in the atmosphere. 相似文献
7.
Shved G. M. Golitsyn G. S. Ermolenko S. I. Kukushkina A. E. 《Doklady Earth Sciences》2018,481(1):958-962
Doklady Earth Sciences - Based on the five-year record of the superconducting gravimeter in Strasburg (48.6° N, 7.7° E), the correlation is calculated between the long-period free... 相似文献
8.
Shved G. M. Ermolenko S. I. Karpova N. V. Wendt S. Jacobi Ch. 《Izvestiya Physics of the Solid Earth》2013,49(2):278-288
Izvestiya, Physics of the Solid Earth - We briefly overview the periodic atmospheric motions in the period range from 1 h to a few dozen days. It is shown that many oscillations recorded by... 相似文献
9.
In any planetary atmosphere there is an uppermost layer in which the molecular thermal conduction is a significant mechanism of forming the thermal structure of the atmosphere. In this paper, the similarity approach is first used to develop the 1-D general model of aforementioned layer. The main concepts of the model are (i) the radiative equilibrium condition at the lower boundary of the layer and (ii) taking into account a single rovibrational band for radiative cooling of the layer. Five dimensionless parameters of the model characterize both “strengths” and altitudinal distributions of heat sources and sinks in the layer, including an effect of the atmosphere under the layer. By fitting the modeled temperature profile to the mean empirical profile, both the magnitudes of the parameters and the relations between them have been determined for the Earth and Mars. Distinctions between these planets in both the parameter magnitudes and relationships can be accounted for by distinction in composition of their atmospheres. For both planets the model shows weak sensitivity of the modeled temperature profile to significant changes in the state of the underlying atmosphere. The model demonstrates some prognostic capabilities. Namely, the fitting reveals presence of O in the martian thermosphere. (However, the fractional O abundance is overestimated.) From drag deceleration of the MGS orbiter the mean temperature profile of the martian thermosphere between 115 and 170 km has been derived for the solar zenith angle of 45°-70°, the solar longitude of 30°-80°, and the latitude range from −10° to 60°at a moderate level of solar activity. 相似文献
10.
The standard problem of radiative transfer in a rovibrational band is formulated for an optically semi-infinite plane-parallel planetary atmosphere using a model of a linear molecule with two vibrational states. The solution of the problem describes the variation with height of the population of the excited vibrational state due to the existence of the upper boundary of the atmosphere. We seek this solution as a function of the specially introduced dimensionless parameters—the atmosphere depth and four similarity parameters—and study it for the parameter values that can be realized in the planetary atmospheres, including the atmospheres of extrasolar planets. It is shown that an increase in the optical density of the atmosphere can reduce the population of an excited vibrational state in the band at the upper boundary of the atmosphere by as much as several orders of magnitude as compared to the population corresponding to the optically thin band limit. The anomalous decrease in the opacity of the atmosphere, when only several lines of the band are involved in radiative transfer, is predicted. We also determined the accuracy of calculating the population in the approximation of the Doppler line profile. An approximate formula is obtained for the dimensionless height of the boundary of the layer in which the local thermodynamic equilibrium exists for vibrational states. We propose a model and the formula following from this model to roughly evaluate the decrease in this height due to the impact on the population of additional radiative transitions between the state being considered and the underlying state belonging to another vibrational mode of the molecule. 相似文献