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171.
Karel Pěč Jana Pěčová Oldřich Praus Reviewer M. Hvoždara 《Studia Geophysica et Geodaetica》1977,21(3-4):383-393
n ¶rt;a, n¶rt;mau 531 au ¶rt; u aum m u¶rt;uu n mumu ana¶rt;, ¶rt; u -m n, aauum ¶rt;um u u amuaa n¶rt;naa ma ua aama. uu nmam an¶rt;u ¶rt; u aum aam ¶rt;au cuu uP
n
m
, n¶rt;am mn n=1, 2, 3 u 5 (m n). u uua ¶rt;a¶rt;amu uu n¶rt;mauu uum au (a. 1) u u n aumam uu nmu, m n¶rt;mam u¶rt; am uuu ¶rt; u aum (u. 1–4). annuau 2
u 5
mn nm ma am mmmu m (u. 5, 6). ama uuu u m aam amu uu uma. 相似文献
172.
Summary The 272 kHz ionospheric absorption has been measured at the Prhonice Observatory by the A3 method (oblique incidence) for a long period. The results of the comparison of these absorption data with indices of solar, geomagnetic and cosmic ray activity are presented for large solar zenith angles. The day-time absorption (x 75° – 85°) is described well by these indices and appears to be affected particularly by direct solar Lyman- radiation. The night-time absorption (x>100°), however, is not described sufficiently by the indices used. 相似文献
173.
Václav Bucha Reviewer F. Rein Reviewer J. Bochníček 《Studia Geophysica et Geodaetica》1977,21(3-4):350-360
Summary As a result of investigating the relations between the variations of geomagnetic activity and meteorological factors [1, 2] a mechanism of solar-terrestrial relationships and a model of the changes of atmospheric circulation in the Northern Hemisphere are proposed; this provides an explanation of the causes of the fluctuation of the climate, of dry and cold periods and differing vegetation conditions in various years in dependence on the intensity of geomagnetic activity. 相似文献
174.
Summary The theory of secondary vorticity is used to explain the essence of so-called secondary or upper vorticity centres, discovered on satellite photographs. The general equation of vorticity, which is then adjusted by means of the equations of state and motion, is transformed into a specially selected intrinsic co-ordinate system. Three-component equations of vorticity are discussed for cases important meteorologically. The conclusion could be drawn that the secondary vorticity centres may be identified with centres of so-called secondary vorticity and that the theoretical facts about their origin and occurrence may be used, together with satellite photographs, to improve weather forecasts. 相似文献
175.
176.
Summary Relatively good correlation between such remote phenomena as microseisms, geomagnetic activity and ionospheric absorption of radio waves has been observed. These phenomena are probably connected by a considerably increased penetration of energetic particles into the atmosphere under conditions of geomagnetic activity. 相似文献
177.
Summary As a result of investigating the energy flow, transmitted by short-period HM waves, the existence of a frequency limitation was found at the theoretical investigation of the propagation of these HM waves. 相似文献
178.
179.
180.
On 13 May 2000 parts of a penumbra were observed in an active region NOAA 8990 with the La Palma Stokes Polarimeter attached
to the Swedish Vacuum Solar Telescope. The stratification over the solar atmosphere of different physical parameters is retrieved
from these data by using the Stokes inversion based on response functions. The results confirm the previous findings of the
penumbral structure. In general, the magnetic field becomes weaker and more horizontal with increasing distance from the umbra
and the line-of-sight velocities are increasing towards the outer boundary of the penumbra. The results also suggest the existence
of the unresolved fine structure of the penumbra. The stratifications of the temperature and of the magnetic field strength
indicate the presence of rising flux tubes, which were predicted theoretically by Schlichenmaier, Jahn and Schmidt (1998,
Astron. Astrophys.
337, 897). 相似文献