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101.
102.
Emil M. Apostolov Vojtěch Letfus Reviewer J. Pýcha 《Studia Geophysica et Geodaetica》1989,33(4):379-390
Summary The time variations of the amplitudes and phases of the semi-annual variation in geomagnetic activity, characterized by the linear planetary index aa, have been analysed for the period 1868–1985. The results provide qualitative confirmation of Murayama's conclusions [13] about the systematic f phase in dependence on the changes in the level of solar activity and give support to Russel-McPherron's mechanism [16] concerning the effect of the predominant polarity of the interplanetary magnetic field. A distinctly expressed variation of the phase differences in the course of the sunspot cycle and of the 22-year cycle, and specific variations related to the sequence of four consecutive cycles have been established, as well as a well-defined 90-year period, all of them as a reflection of analogous variations in solar activity. The variations of the phase differences observed around the equinoxes can be explained by the combined effect of the mechanisms of the axial and equinoctial hypothesis. It is assumed that a displacement of the maxima of the semi-annual variation to dates after the equinoxes will be observed in the ascending parts and a reverse displacement towards the equinoxes and earlier dates in the desccending parts of the following sunspot cycles 22 nad 23.On leave from the Geophysical Institute of the Bulgarian Academy of Sciences, Akad. G. Bonchev Str. bl. 3, Sofia 1113, Bulgaria. 相似文献
103.
Summary We find no effect of the interplanetary magnetic field(IMF) sector boundary crossing in ozone at altitudes ranging from the middle stratosphere(10 hPa) to the lower mesosphere(0.4 hPa) at middle latitudes(40°–60° N), based on winter data over the period of December 1979–December 1982.
Резюме Мы не нaшлu нuкaко о эффекma nересеченuя секmорноŭ рaнuцы межnлaнеmно о мa нumно о nоля в озоне в облaсmu высоm меж?rt;у сре?rt;неŭ сmрamосфероŭ(10 Пa) u нuжнеŭ мезосфероŭ(0,4 Пa) нa сре?rt;нuх шuроmaх(40°–60° с.ш.), nрuменяя зuмнuе ?rt;aнные зa nерuо?rt; ?rt;екaбрь 1979 – ?rt;екaбрь 1982 .相似文献
104.
Summary Sets of virtual poles corresponding to sets of geomagnetic field values at equidistant points, lying along circles of latitude, were defined on the basis of the 1980 IGRF extending to degree and order 8. Certain places on the Earth's surface yield virtual poles lying very close together. The segments of the virtual pole paths, corresponding to these places, have a large curvature. The mentioned places of the Earth's surface are supposed to be areas with a low rate of the westward drift. They form continuous zones that show a certain relation to global-tectonics features.
uum ¶rt; 8- n¶rt;a ¶rt;a¶rt; aaumu n 1980 u u nmu uma n, mmmu nm uu n ma, a u¶rt;umam ¶rt; naa m ma nmu nua¶rt;am uma n, m uu ¶rt; ¶rt;. amu u, mmmu mu ma, um uu. ¶rt;naam, m nm ma nmu m amu, m m ana¶rt; ¶rt;a ua. u am n na, m naam a m uua mmuu.相似文献
105.
Jan Peczkis 《Climatic change》1988,12(2):199-208
Conclusions An extinction optical depth of 20 is necessary for total darkness (NAS, 1985), although a considerably lower value than that can produce near-total darkness because scattered light does not generate shadows and contrast. It can be seen that the Dresden firestorm smoke cloud, calculated under the conditions usually assumed in nuclear winter calculations, should have resulted in total darkness over a vast area.Using the 500 mb chart, it can be retrodicted that the smoke plume, as part of the counterclockwise circulation about the low over southern Sweden, was over central Poland as dawn broke on the 14th. Indeed, at 9 AM (Table I), smoke from what had been Dresden should have been passing over what had been Warsaw. Depending upon the specific size of the plume at the time, anywhere from a few hundred thousand to over ten million people should have been plunged into darkness.It appears unlikely that such extensive darkening could have gone unreported (especially in the light of the heightened awareness resulting from wartime conditions, and the proximity of the Soviet/German front). This has direct implications for the aforementioned initial uncertainties in nuclear winter. Possible explanations include: (a) Very low smoke emission factors - perhaps even lower than 0.001 (Broyles, 1985); (b) Substantial removal of smoke in the black rain that followed the firestorm (Irving, 1963, p. 175). Values for prompt smoke removal reaching 90% are not out of the realm of possibility (Schneider et al., 1986; Penner, 1986).The present author is of the opinion that more effort should be expended by students of the nuclear winter phenomenon to learn from WWII mass urban fires. Many eyewitnesses to these events must still be living, and there must be at least some scientifically-useable material in archives. For example, there is a 122-m, 10-min motion film of the Dresden firestorm (Irving, 1963, p. 159). It is in the film archives of the Imperial War Museum. Perhaps some new details of firestorm genesis, spread, etc. could be learned from it. There must be other log books, such as the one of Kraus (1986), which could well yield scientificallyvaluable information. 相似文献
106.
Plastic particles were found to be common pollutants in stomachs of Wilson's Storm Petrels and Cape Petrels breeding on the Antarctic continent. Highest incidence of plastics was found in chicks of Wilson's Storm Petrels that had died before fledging. Few or no plastics were found in Snow Petrels and Antarctic Petrels. Evidence suggests that most plastics originate from wintering areas outside the Antarctic, and that relatively few plastics are available in Antarctic waters. Possible hazards of plastic levels observed in Wilson's Storm Petrels are discussed. 相似文献
107.
Thomas Foken Jan Pretel Reviewer J. Bednář Reviewer Z. Jaňour 《Studia Geophysica et Geodaetica》1988,32(3):318-328
In the present paper the first results of the international KOPEX-86 experiment are presented. The experiment took place at the Kopisty Atmospheric Observatory of the Institute of Physics of the Atmosphere in Prague as part of a special project of the Commission of the Academy of Sciences in Planetary Geophysics (KAPG) in June and July 1986. Using 4 ultrasonic anemometers at 4 levels up to 80 m, Doppler-SODAR and wind-, temperature- and radiation balance gradients from 2 to 80 m, a complex investigation of the atmospheric boundary layer in an industrial area was made. The authors present the first results of
am n mam ¶rt;a¶rt; numa -86. num n¶rt;u mu u u u 1986. a num mu amuu mumma uuu am aa nma . u nu 4 amuu am a 4 ma ¶rt; 80 , ¶rt;nn ¶rt;aa u uua¶rt;um mu ma, mnam u a¶rt;uauu 2 ¶rt; 80 n¶rt;uu n u¶rt;au nau am. m n¶rt;aam n mam, aau
相似文献
| the anthropogenic influence on the energy exchange in the atmospheric boundary layer. |
| the influence of a complex terrain on the turbulent characteristics and their vertical distribution. |
| u¶rt;au amn ¶rt;mu a muu na am, |
| uu n mmu a aamumuu mmmu u a u mua an¶rt;u. |
108.
109.
Zdeněk Šimon Jan Kostelecký Antonín Zeman Reviewer L. Skalský 《Studia Geophysica et Geodaetica》1988,32(1):16-23
Summary It is recommended that the data from measurements with supraconducting gravity meters be also analysed with regard to verifying the gravitation absorption hypothesis. Based on theoretical data from a3-year period, the spectrum of the assumed effect of shielding the gravitational influence of the Sun by the Earth's body on the value of the acceleration of gravity has been calculated for the tidal station Brussels (Figs 2a–e).
¶rt;aam aauuam ¶rt;a uu n¶rt;uaumau ma mu u nuunm n¶rt;auaumauu. a mmuu ¶rt;a a mmu nu¶rt; u nm n¶rt;naa ma auauaumau ¶rt;mu a m a uu u u mmu ¶rt; nuu mauu (u. 2a–).相似文献
110.