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1.
I.N. Fedulina 《Studia Geophysica et Geodaetica》1998,42(4):521-532
The variations of total ozone at Alma-Ata (43°N, 76 °E) and ozone profiles obtained by balloon sounding at Tateno (36°N, 140°E), Wallops Island (38°N, 75°W) and Cagliari (39°N, 9°E) in the periods of Forbush decreases (FD) in galactic cosmic rays have been analysed. A decrease of total ozone was observed in the initial stage of the FD and an increase 10–11 days later. The average total deviations calculated using the superposed epoch method for 9 FD events are equal to 30 D. U. in the positive and to –18 D. U. in the negative phase. The changes of average ozone profiles, associated with 26 FD events, are more significant in the lower stratosphere and upper troposphere. The decrease of the partial ozone pressure at a height of 12–15 km is about 30 mb. These vertical variations of ozone coincide with the average changes of the respective temperature profiles. A cooling, on the average, of 3°C was observed at 12–15 km, and a heating of 4°C below this level. 相似文献
2.
Ozone depression in the polar stratosphere during the energetic solar proton event on 4 August 1972 was observed by the backscattered ultraviolet (BUV) experiment on the Nimbus 4 satellite. Distinct asymmetries in the columnar ozone content, the amount of ozone depressions and their temporal variations above 4 mb level (38 km) were observed between the two hemispheres. The ozone destroying solar particles precipitate rather symmetrically into the two polar atmospheres due to the geomagnetic dipole field These asymmetries can be therefore ascribed to the differences mainly in dynamics and partly in the solar illumination and the vertical temperature structure between the summer and the winter polar atmospheres. The polar stratosphere is less disturbed and warmer in the summer hemisphere than the winter hemisphere since the propagation of planetary wave from the troposphere is inhibited by the wind system in the upper troposphere, and the air is heated by the prolonged solar insolation. Correspondingly, the temporal variations of stratospheric ozone depletion and its recovery appear to be smooth functions of time in the (northern) summer hemisphere and the undisturbed ozone amount is slighily, less than that of its counterpart. On the other hand, the tempotal variation of the upper stratospheric ozone in the winter polar atmosphere (southern hemisphere) indicates large amplitudes and irregularities due to the disturbances produced by upward propagating waves which prevail in the polar winter atmosphere. These characteristic differences between the two polar atmospheres are also evident in the vertical distributions of temperature and wind observed by balloons and rocker soundings. 相似文献
3.
4.
Kaichi Maeda 《Pure and Applied Geophysics》1987,125(1):147-165
The global structures of annual oscillation (AO) and semiannual oscillation (SAO) of stratospheric ozone are examined by applying spherical harmonic analysis to the ozone data obtained from the Nimbus-7 solar backscattered UV-radiation (SBUV) measurements for the period November 1978 to October 1980. Significant features of the results are: (1) while the stratospheric ozone AO is prevalent only in the polar regions, the ozone SAO prevails both in the equatorial and polar stratospheres; (2) the vertical distribution of the equatorial ozone SAO has a broad maximum of the order of 0.5 (mixing ratio in g/g) and the maximum appears earlier at high altitude (shifting from May [and November] at 0.3 mb [60 km] to November [and May] at 40 mb); (3) above the 40 km level, the maximum of the polar ozone SAO shifts upward towards later phase with altitude with a rate of approximately 10 km/month in both hemispheres; (4) vertical distributions of the polar ozone AOs and SAOs show two peaks in amplitude with a minimum (nodal layer) in between and a rapid phase change with altitude takes place in the respective nodal layers; and (5) the heights of the ozone AO- and SAO-peaks decrease with latitude. The main part of AOs and SAOs of stratospheric ozone including hemispheric asymmetries is ascribable to: (i) temperature dependent ozone photochemistry in the upper stratosphere and mesosphere, (ii) variations of radiation field in the lower stratosphere affected by the annual cycle of solar illumination and temperature in the upper stratosphere and (iii) meridional ozone transport by dynamical processes in the lower stratosphere. 相似文献
5.
Homer T. Mantis Christos C. Repapis Christos S. Zerefos 《Pure and Applied Geophysics》1980,119(2):213-230
Station records of ozone observations have been critically reviewed to investigate the reality of the reported maximum in total ozone over northwest Europe in July. The existence of a longitudinal excess of ozone over the British Isles is confirmed but strong horizontal gradients can be verified only over central Europe and there is no evidence for east-west gradients over the Atlantic. Ozone sounding data as well as total ozone daily variability make it most plausible that the ozone excess over northwest Europe is confined to the lower stratosphere. The isopleths in the region of strong ozone gradients are parallel to the mean flow at 100 mb as required by the calculated constraint on the magnitude of the mean flow advection. It is proposed that analyses of the ozone distribution over oceanic areas could be improved by extending ozone isopleths parallel to the mean lower stratospheric flow from land areas where the pattern is better defined. 相似文献
6.
Mani A. Sreedharan C. R. Joseph P. V. Sinha S. S. 《Pure and Applied Geophysics》1973,106(1):1192-1199
A series of ozone soundings were made at New Delhi (77°E 28°N) from 21 to 30 January 1969 and 10 to 22 February 1972 to study the changes in the vertical distribution of atmospheric ozone associated with western disturbances. The sonde used was the Indian ozonesonde made in the Instruments Laboratories at Poona.In February 1972, two western disturbances moved eastwards in quick succession across the western Himalayas, the first between the 11th and 13th and the second between the 13th and 15th. Associated with the first tropospheric trough was a high-speed jet stream with wind speeds reaching 180 knots, when the tropopause descended to 304 mb over Delhi. The second trough had no high-speed jet associated with it and the tropopause was at 227 mb. Ozone maxima were observed at 350, 180 and 125 mb in addition to the main peak at 35 mb in association with the upper tropospheric troughs over Delhi and its neighbourhood. A similar lowering of the tropopause and the influx of ozone in shallow layers was observed during the passage of two upper air troughs in January 1969. The study shows that with the approach of upper tropospheric troughs and the simultaneous lowering of the tropopause there is an increased influx in shallow layers of middle latitude ozone-rich air through breaks in the tropopause, replacing the subropical ozone-poor air over the station. 相似文献
7.
Summary The intensity of the polar vortex at 10 mb is used to calculate theoretical values of mean total ozone north of 40° latitude. A satisfactory fit is attained between the development in time of the theoretical ozone and that of the mean of the observed total ozone. The results lead to the conclusion, that a one-cell mean meridional motion relative to the polar night vortex is important for the transport of heat and ozone. 相似文献
8.
The global distribution of total ozone is derived for the period April, May, June and July of 1969 from Nimbus-3 Infrared Interferometer Spectrometer (IRIS) experiment. Preliminary estimates of ozone amounts from Nimbus-4 IRIS for the same period of 1970 show similar results. The standard error of estimation of total ozone from both IRIS experiments is 6% with respect to Dobson Spectrophotometer measurements. A systematic variation in the ozone distribution from April to July in the tropical, middle and polar latitudes is observed indicating the changes in the lower stratospheric circulation.The total ozone measurements show a strong correlation with the upper tropospheric geopotential height in the extratropical latitudes. From this relationship total ozone is used as a quasi-stream function to deduce geostrophic winds at the 200 mb level over extratropical regions of the northern and southern hemispheres. These winds reveal the subtropical and polar jet streams over the globe.Allied research associates. 相似文献
9.
Summary Recent satellite experiments have measured the radiance of the earth at ultraviolet wavelengths and the data thus obtained has been used to determine atmospheric ozone concentrations. It is pointed out in this paper that in the presence of significant concentrations of aerosols at high altitudes, it is not possible from observations of backscattered ultraviolet radiation to separate the effects of aerosols from those attributable to ozone.The earth's daytime horizon was scanned on several occasions between 1963 and 1967 from an altitude of 80 km. For at least one of the flights analyzed we interpret the data to indicate the existence of an aerosol layer at 50 km. This observation, in combination with related observations of other experimenters, implies a limitation on the ability of the backscattered ultraviolet technique to determine ozone concentrations, particularly at altitudes in the region between 35 and 50 km. This limitation may be overcome by altering the viewing geometry and making observations of the earth's horizon. Data thus obtained may be used to deduce the concentrations of both ozone and aerosols. 相似文献
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11.
Heath Donald F. Mateer Carlton L. Krueger Arlin J. 《Pure and Applied Geophysics》1973,106(1):1238-1253
Summary In April 1970 the Backscatter Ultraviolet (BUV) experiment was placed into orbit aboard the Nimbus-4 satellite. This double monochromator experiment measures ultraviolet terrestrial radiance at twelve discrete wavelengths between 2550 Å and 3400 Å. Approximately 100 scans covering a 230 km square are made between terminator crossings on the daylight side of the earth. A colinear photometer channel with the same field of view is used to derive the Lambert reflectivity of the lower boundary of the scattering atmosphere. The extraterrestrial solar irradiance is measured at the northern terminator. The instrument has currently produced almost three years of nearly continuous data which are being used to infer the high-level ozone distribution and total ozone on a global basis. The high-level ozone data have been verified by independent coincident rocket ozone soundings, and the total ozone values show good agreement with Dobson spectrophotometer determinations as well as those made with the Infrared Interferometer Spectrometer also on Nimbus-4. An increase has been observed in equatorial radiance at 2550 Å relative to 2900 Å, which seems to indicate that the amount of ozone in the upper stratosphere is related to the eleven-year solar cycle. 相似文献
12.
For the period December 1970, comparison is made between the monthly average analyses (mapped fields) of the Backscatter Ultraviolet (BUV) total ozone data and the ground-based observations. In particular, significant differences of over 50 Dobson units are noted over the region of the North Atlantic Ocean with the BUV of greater magnitude than the ground-based data. As part of the overall verification program, both analyses are compared against the 100 mb height fields. The results indicate that the BUV analysis in the region of question is the more consistent of the two. 相似文献
13.
《Journal of Atmospheric and Solar》2002,64(3):283-289
A sudden transient increase of the solar ultraviolet (UV) radiation was detected with a ground-based photometer in Madrid (Spain, 41°N, 3°W) on 25 November 1996 (Cordoba et al., 2000. UV-B irradiance at Madrid during 1996, 1997 and 1998. J. Geophys. Res. 105 (D4) (2000) 4903–4906). The data obtained by the TOMS satellite instrument revealed that this event was related to a reduction of the total ozone column values. This low ozone episode has been analysed. The ozone decrease was accompanied by a reduction of air temperature in the lower stratosphere. The anti-correlation between total ozone and air parcel height along the three-dimensional isentropic back-trajectories suggests that the adiabatic uplift of air contributed significantly to both the ozone and the temperature decreases observed. The uplift could be caused by the propagation into the lower stratosphere of the high-pressure cell located over the mid-Atlantic region. 相似文献
14.
This study demonstrates that ordinary kriging in spherical coordinates using experimental semi-variograms provides highly usable results, especially near the pole in winter and/or where there could be data missing over large areas. In addition, kriging allows display of the spatial variability of daily ozone measurements at different pressure levels. Three satellite data sets were used: Total Ozone Mapping Spectrometer (TOMS) data, Solar Backscattered UltraViolet (SBUV), and the Stratospheric Aerosol and Gas Experiment (SAGE II) ozone profiles. Since SBUV is a nadir-viewing instrument, measurements are only taken along the sun-synchronous polar orbits of the satellite. SAGE II is a limb-viewing solar occultation instrument, and measurements have high vertical resolution but poor daily coverage. TOMS has wider coverage with equidistant distribution of data (resolution 1° × 1.25°) but provides no vertical information. Comparisons of the resulting SBUV-interpolated (column-integrated) ozone field with TOMS data are strongly in agreement, with a global correlation of close to 98%. Comparisons of SBUV-interpolated ozone profiles with daily SAGE II profiles are relatively good, and comparable to those found in the literature. The interpolated ozone layers at different pressure levels are shown. 相似文献
15.
The intensity of stars at wavelengths in the Hartley continuum region of ozone has been monitored by the University of Wisconsin stellar photometers aboard the OAO-2 satellite during occultation of the star by the earth's atmosphere. These occultation data have been used to determine the ozone number density profile at the occultation tangent point. The nighttime ozone number density profile has a bulge in its vertical profile with a peak of 1 to 3×108 cm–3 at approximately 83 km and a minimum near 75 km. The ozone number density at high altitudes varies by as much as a factor of 4, but does not show any clear seasonal variation or nighttime variation. The retrieved ozone number density profiles define a data envelope that is compared with other nighttime observations of the ozone number density profile and also the results of theoretical models.Calculations are also presented that illustrate the difference in retrieving the bulge in the ozone number density profile from stellar and solar occultation data.The National Center for Atmospheric Research is sponsored by the National Science Foundation. 相似文献
16.
The vertical profiles of ozone and temperature from a series of balloon soundings at Delhi (28°N), Poona (18°N) and Trivandrum (8°N) were studied with synoptic meteorological data. While both ozone and temperature profiles show similar variations over all three stations, ozone maxima being always associated with thermally stable layers, the variations are most pronounced over Delhi, particularly in winter and in early spring when a series of western disturbances pass over north India. Both ozone and temperature profiles over Delhi show a layer structure characterized by a series of maxima and minima in both the vertical distribution of ozone and temperature and these are most pronounced in the lower stratosphere. These variations are associated with the influx of ozone-rich middle latitude stratospheric air over Delhi replacing subtropical air. 相似文献
17.
Fernando Calvo Canales 《Pure and Applied Geophysics》1965,62(1):215-223
Résumé L'analyse des sondages effecturés au cours de quinze mois à partir de la Station Scientifique du Val-Joyeux près de Paris, montre que les couches où la pression partielle d'ozone est maximale ne sont pas celles où la température est maximale. La pression partielle d'ozone de ces couches n'est pas en relation avec la température de la tropopause, mais est conditionnée par la position géographique sur l'Europe du plus proche thalweg.L'épaisseur réduite totale d'ozone est indépendante de la direction du flux à 100mb, mais présente une relation non linéaire avec l'altitude de la deuxieme tropopause.L'existence d'une relation entre l'allure de la courbe de répartition verticale de l'ozone et la situation météorologique au niveau du sol quarte jours après le sondage, est mise en évidence.
Summary An analysis of the soundings launched at the Val-Joyeux Scientific Station during 15 months shows that the layers containing higher ozone partial pressure are not those of higher absolute temperature. Their ozone pressure has no relation with the temperature of the tropopause but is conditioned by the position of Europe nearest through.The total ozone amounts are independent of the direction of the 100-mb flow but present a non-linear correlation with the second tropopause height.The existence of certain relations between ozone vertical profiles and the meteorological situation at the surface four days after the sounding is pointed out.相似文献
18.
V. N. R. Mukku 《Pure and Applied Geophysics》1991,136(2-3):211-216
The temporal variations in mean zonal wind, horizontal temperature gradient at 30 mb and Total Ozone in Antarctic Spring (1 Sept.–30 Nov.) for nine seasons (1979–1987) were examined. The ozone hole filling commenced when the zonal flow decelerated to 50–58 m.sec–1 at 30 mb. Our calculation of Rossby critical wave number with vertical shear suited for Antarctic Spring indicated that flow is preconditioned for vertical propagation of Rossby critical wave number two at this range of zonal flow. This preconditioning can be attributed to the diabatic heating in the Antarctic Spring since no sudden minor warmings/coolings have occurred during the period. 相似文献
19.
Newell Reginald E. Boer George J. Dopplick Thomas G. 《Pure and Applied Geophysics》1973,106(1):1531-1543
Computations of the mean meridional motion field in the stratosphere are applied to ozone distributions to evaluate the associated ozone concentration changes. These changes are compared with those produced by photochemical and quasi-horizontal eddy processes. For the period January–April 1964 there is a cooperative action between the mean and eddy motions with mean subsidence in middle latitudes supplying ozone to be carried polawards and equatorwards by quasi-horizontal eddy processes. At low latitudes mean horizontal motions offset the eddy transport while at high latitudes mean rising motion is the offsetting term. The mean ozone flux through 50 mb, 3.5×1029 molecules sec–1, is comparable with the fluxes evaluated by other techniques.The spring maximum is thought to be due to a modulation of the energy supply to the stratospheric eddies which, in turn, force the mean motions. Longer-term changes are to be expected; for example during Ice Ages when increased tropospheric eddy activity is anticipated there should be higher total ozone. 相似文献
20.
The results of the observations of both total and layered ozone content of the atmosphere, the latter from C wavelength Umkehr observations, made in Lisbon (38° 46N; 09° 09W) during the period 1967 to 1971 by the Serviço Meteorológico Nacional, are analysed on a statistical basis in relation to the flow and temperature fields of the atmosphere, namely in relation to the position of the tropospheric jet axis and thê 100 mb air temperature.The preliminary results of the analysis show that the yearly mean variation of the total O3 follow the very well-known trend as observed for other geographical coordinates, with a winter to spring maximum. In addition, the same parameter is positively correlated to the 100 mb temperature field for the seasons of the year, and it was found, both on a large time-scale and for synoptic distributions, that the total amount of O3 is significantly higher a few hundreds of kilometres to the left of the jets looking downstream than to the right, so that mean cross-flow gradients of O3 are field features to be taken into account.The time-height distributions of ozone from the Umkehr technique has revealed, in the long-term mean used, a descent of the level of the maximum of around 20 mb depth from the summer-winter period to spring, but this descent may be much more pronounced on occasions, as revealed by the preliminary analysis of a few days' period of important ozone changes in relation to the potential temperature and jet axis position. this showed, in addition, the existence of varying gradients along the stream, whereby differences in circulation along the jet complex may be implied.Work done for the Project LF2 of the IAC 相似文献