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[en] A method is described for the analysis of the natural 14CO concentration in the atmosphere. It is based on the separation of CO from ambient air, followed by the determination of its 14C-content by proportional gas counting employing a low volume counter. The method is described in detail. The concentration of 14CO at midlatitudes (510N) exhibits a marked seasonal variation with a winter maximum of 25 +- 2 molecules/cm3 and a minimum of 11 +- 1 molecules/cm3 during summer. Measurements at different latitudes show a decrease of the 14CO concentration from the pole to the equator. Interpretations of the data are based on calculations with a 2-d-time dependent model. From the simultaneous examination of the 14CO and 12CO balance in the troposphere it is possible to derive the two most important parameters for the global cycle of atmospheric CO: the concentration of OH radicals in the troposphere - and thus the lifetime of CO - and the contribution of biological sources to the CO budget. From this work the concentration of OH radicals in the troposphere is estimated to average around 6.5 x 105 molecules/cm3, biological sources are shown to contribute about 12.5 x 1014g 12CO per year to the CO budget. (orig.)
[en] A brief introduction is given on how the ozone layer formed and about the factors depleted ozone layer such as chloro bromo compounds and so on; then, it follows the processes which destroy the troposphere. The damaging effect of ultraviolet radiation is described. Finally,the action taken to reduce the depletion of ozone layer is presented
[en] Complete text of publication follows. As was recently found, the atmospheric boundary layer comprises aeroelectric structures manifested in short-period electric-field pulsations (with period from several to several hundred seconds). The formation of aeroelectric structures is most rapid under conditions of intensive convection. The sizes of such structures are determined by characteristic variation scales of aerodynamic and electrodynamic parameters of the atmosphere (including the surface-layer height and the atmospheric 'electrode' layer scale) as well as heating inhomogeneities of the ground (water) surface. Formed as a result of convective processes or capture of positive and negative charged particles (both ions and aerosols) by convective cells, aeroelectric structures move in an air flow along the Earth's surface. Since the further evolution of convective cells results, in particular, in cloud formation relationship between such convective cells of the atmosphere and the aeroelectric-structure evolvement leads to the assumption that charge separation and accumulation processes are characteristic of even early stages of cloud formation. Obviously, development of the methods of diagnostics and modeling of aeroelectric structures is important for a study of both convective and electric processes in the lower troposphere. The test-structure method developed in this paper is aimed, first of all, at solution of the mentioned problems. This paper is devoted to numerical modeling of the electric-field dynamics in the atmosphere by the test-structure method. The method of diagnostics of aeroelectric-structure (AES) parameters based on measurement of short-period electric-field fluctuations is proposed and implemented. Thunderstorm applications of the test-structure method based on the local experimental data is considered. Aerosol influence on relaxation time of AES is investigated.
[en] Complete text of publication follows. We present some observed effects of the equatorial QBO and the Sun on polar atmospheric dynamics. The analysis primarily uses data from mesospheric wind radars and ECMWF and NCEP reanalysis. The results demonstrate the importance of treating the atmosphere as a single connected system both vertically from the troposphere to the thermosphere, and horizontally from one pole to the other. Examples include the combined solar and QBO influence on (i) planetary wave propagation between the winter troposphere and summer polar mesosphere, (ii) the dynamics of the polar vortex in the Antarctic mesosphere, and (iii) the variability of major polar atmospheric modes.
[en] The solar-troposphere effect is discovered in the Southern Hemisphere as well as in the Northern one. At the fourth-fifth day after the entering of the Earth into the solar corpuscular streams, an increase of instability of the troposphere is observed in the moderate latitudes of the Southern Hemisphere. (The variance of the 24-hour pressure differences increases at 16% on the average). The assumption of its being accidental is rejected at the significance level of 0.2 per cent. But the hypothesis of the solar-troposphere effect being absent both in Southern Hemisphere and the Northern one is rejected at the significance level of 2x10-6
[en] Complete text of publication follows. Differences in the external part of the vertical geomagnetic component point to the existence of local inhomogeneities in the magnetosphere or the ionosphere. The correlations between the new magnetic index η and the ionospheric characteristics - foE (E layer critical frequency) monthly median deviations - are analysed. The analysis was based on one-minute data recorded at each of 20 European Magnetic Observatories working in the INTERMAGNET network and from 18 ionosondes for 2004. The high peaks (2-2.7) of the new magnetic index correlate in time with large (+1.6 MHz and -1.1 MHz) punctual median deviations of foE. Such punctual deviations can suggest local inhomogeneities (vertical drifts) in the ionosphere. The correlation in space is not trivial. The strong peak of ? is situated on the map between the positive and negative deviations of foE. Additional observation is connected with correlation in time of the high ? value with the negative median deviations of h'F2 (in some cases up to -90 km). The increase of the electromagnetic activity can cause lightnings in troposphere. Ionospheric data are sparse in time and in space in opposite to the magnetic data. The map of the magnetic indices can suggest the behaviour of ionospheric characteristics in the areas where we have no data.
[en] An apparatus capable of directly sampling ions in the troposphere has been developed. This device can mass analyse and detect ions at concentrations as low as 102 - 103 ion/cm3 at atmospheric pressures (760 torr) and makes use of a flow opposed drift tube to concentrate and extract the ions to be sampled. High pressure ion optics are used to keep the ion density constant while increasing the ion drift velocity. The high ion drift velocity is used to push the ions through an inert buffer gas and an exit aperture into a high speed differentially pumped high vacuum region where they are focused, mass analysed, and detected. This type of apparatus can contribute considerably to both our understanding of ion chemistry and to our knowledge of certain trace neutral concentrations in the troposhere. (Authors)
[en] Complete text of publication follows. It is well known that the interannual variability of the stratospheric winters over the Arctic is very large. Based on data of more than 60 winters this variability has been studied with the aim of understanding and possibly forecasting the type of the coming winter, in the stratosphere and also in the troposphere. Today, there is general agreement that the variability of the stratospheric circulation during the Arctic winters is due to different forcing mechanisms: To the tropospheric planetary waves which penetrate into the stratosphere; to the Quasi-Biennial Oscillation (QBO) and the Southern Oscillation (SO) in the Tropics which influence the stratospheric polar vortex; and to the 11-year sunspot cycle (SSC) which interacts with the QBO and probably also with the SO. For the winter 2008/09 all of the known signals pointed to a stable, cold stratospheric polar vortex throughout the winter, but in the real atmosphere a Major Midwinter Warming (MMW) developed in January and February with record breaking temperatures. The synoptics of this winter will be discussed in the context of all of the above mentioned forcing mechanisms.
[en] Complete text of publication follows. Vertically propagating diurnal tides are a leading agent of coupling between the troposphere and the thermosphere. Due to their exponential increase in amplitude with height, tides often dominate the spectrum of lower thermospheric variability, and can influence the variability of atmospheric composition and ionization. Nonmigrating tides are known to play a key role in these processes. However, direct measurements of neutral atmospheric variables above the highest levels of TIMED sampling (105 km for winds and 120 km for temperature) appear to be confined to winds at 400 km. We present direct observations of nonmigrating tides in the 90--270 km range inferred from the UARS wind imaging interferometer (WINDII). Analyses of daytime winds at low latitudes show a prominent zonal wavenumber 4 wave extending to 180 km, that we convincingly interpret as an eastward-propagating diurnal wavenumber 3 (DE3) viewed from the satellite perspective. This finding supports the idea that DE3 is a leading source of Fregion anomalies reported in electron density. We also identify a large wavenumber one pattern in the daytime horizontal wind, that may indicate nonlinear tide-planetary wave interactions.
[en] Thishs monographic study presents the dynamics of hydrogen in t e Earth's atmosphere. Atomic hydrogen is produced in the homosphere through a complex system of chemical reaction in wich molecules of 2, H2O, C 4 s ''parent '' molecules are involved. The maximum production of H appears at 8O km resulting a concentration of the order of 108 cm-3. There is a correlation between the total mixing ratio of hydrogen in the homosphere and the global escape flux from the Earth's atmosphere. Two new physical mechanisms which may have a substantial contribution to the total escape flux are presented: ''polar wind'' and charge exchange of H with ''hot'' protons. The possibilities of accretion of hydrogen, as atomic hydrogen or as water from the Earth's atmosphere, are analysed in brief. (authors)