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1.
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   

2.
Total ozone observations in the international network have been used as a basis for the analysis of the mean monthly ozone distribution over the globe for the period 1957–75. It has been found that during the period 1961–70 the total ozone amount increased in the Northern Hemisphere by about 12 percent and that this increase seems to be significant at all latitudes. Although the data were sparse for the Southern Hemisphere, there did not appear to be any significant ozone changes during the 10 year period. Relatively large geographic variations were found in the ozone trends and it is suggested that these variations are related to large scale changes in the atmospheric circular pattern.  相似文献   

3.
A comparison is made of the first two years of Nimbus-4 backscattered ultraviolet (BUV) ozone measurements with the predictions of the Ames two-dimensional model. The ozone observations used in this study consist of the mixing ratio on the 1-, 2-, 5-, and 10-mb pressure surfaces. These data are zone and time averaged to obtain seasonal means for 1970 and 1971 and are found to show strong and repeatable meridional and seasonal dependencies. The model used for comparison with the observations extends from 80°N to 80°S latitude and from altitudes of 0 to 60 km with 5° horizontal grid spacing and 2.5-km vertical grid spacing. The chemical reaction and photolysis rate constants used in the model are those recommended in the report of the NASA Panel for Data Evaluation (1979) Chemical reaction and photolysis rates are diurnally averaged, and the photodissociation rates are corrected for the effects of scattering.It is found that the large altitude, latitude, and seasonal changes in the ozone data agree well with the model predictions. Also shown are model predictions of the sensitivity of the comparisons to changes in the assumed mixing ratios of water vapor, odd nitrogen, and odd chlorine, as well as to changes in the ambient temperature and transport parameters.  相似文献   

4.
Summary Ground-based photometric measurements of spectral sky radiation have been made using a simple filter instrument. Sky radiation intensities measured in the solar vertical at =3200 Å and 3600 Å are compared to infer total ozone. A model of multiple scattering Rayleigh atmosphere serves as a primary reduction parameter. Spectral measurements of all-sky radiance distribution are used to study the effects of haze and clouds on the inference of total ozone. The brightness distribution of clear and overcast sky in ultraviolet is also described.  相似文献   

5.
Bremer and Berger (J. Atmos. Solar Terr. Phys. 64 (2002) 805) applied a correction for trends in the NO concentration and αeff in the interpretation of trends in the low frequency (LF) phase height measurements and obtained results less consistent with model simulations as well as the observed trends in mesospheric temperatures. The correction is shown to be too large most probably due to the application of inappropriate trends in αeff of Chakrabarty (Adv. Space Res. 20 (1997) 2117), which yield a trend in electron density opposite to that which is observed. The discrepancy between the observational data and model-simulated trends of Bremer and Berger (J. Atoms. Solar. Terr. Phys. 64 (2002) 805) in the LF phase heights can be largely removed. Even more important, the trends in mesospheric temperatures inferred by Bremer and Berger (J. Atmos. Solar Terr. Phys. 64 (2002) 805) from trends in the LF phase heights without the inappropriate correction agree well with the results of analysis of a global set of results on trends in the mesospheric temperatures by Beig et al. (Rev. Geophys. 41 (2003) 1015).  相似文献   

6.
A spectroscopic method for optical remote sensing of total ozone (O3) is described. It involves detailed spectral matching of near ultraviolet solar observations with synthetic profiles containing various amounts of ozone absorption. Application of this technique is made to airborne solar measurements in the 3100 to 3600 Å wavelength region. In the 3100 to 3200 Å region, measurements made above the tropopause (around geographic latitude 36.7°N, longitude 121.7°W at 0045 UT on 1/23/74) generally fit synthetic profiles constructed with 0.3 atm cm of O3 absorption andBroadfoot's (1972) extra-terrestrial solar irradiance values. However, there are several sections of the solar spectra where the observed intensity is either significantly higher or lower than the calculated value. In addition, several maxima and minima in the observed spectra do not coincide in wavelength with corresponding features in the synthetic profile. Such problems also appear when comparison is made with synthetic profiles based onArvesen et al.'s (1969) extra-terrestrial solar irradiance measurements. These discrepancies may arise from a combination of sources, including errors in laboratory measured O3 absorption coefficients, the extra-terrestrial solar irradiance values and the presence of other UV absorbing species in the stratosphere.  相似文献   

7.
Total ozone errors for satellite observations at Zhongshan Station in Antarctica are characterized using their relative difference(RD) from ground-based Brewer observations during 1993–2015. All satellite total ozone observations slightly overestimated ground-based ones(with RD less than 4%). This is in contrast to conclusions drawn from global-scale validation studies, where main ground-based reference stations are located in middle latitudes. Given multiple total ozone data per day at Zhongshan Station, observed by a sun synchronous orbit satellite, measurements at the lowest solar zenith angle(SZA)show greatest consistency with Brewer ones, having an overall RD of.0.02–1.15%. Algorithm-retrieved total ozone data from the Total Ozone Mapping Spectrometer(TOMS), including Solar Backscatter Ultra Violet(SBUV), TOMS-Earth Probe(EP), Ozone Monitoring Instrument(OMI)-TOMS, show best agreement with ground-based values; followed by the Global Ozone Measurement Experiment-type Direct Fitting(GOD-FIT) algorithm for the GOME-2A, and finally the Differential Optical Absorption Spectroscopy(DOAS) —Algorithm retrieved products for satellites-detectors of Global Ozone Measurement Experiment(GOME), Scanning Imaging Absorption spectroMetr for Atmospheric CHartographY(SCIAMACHY), and OMI.Satellite total ozone RD presents some statistical characteristics, but no specific trends. DOAS and GOME-2A algorithms have values that significantly increase, when the SZA is above 60°–70°, whereas values for GOME-2A decrease, when the SZA is80–85°. Satellite total ozone RD is a minimum, when the Brewer total ozone is 300–350 DU, with an obvious increase in RD values for DOAS-and GOME-2A, when the Brewer total ozone is 150–300 DU. Satellite total ozone RD obviously increases,as the time difference between satellite overpasses and Brewer measurements grows. Specifically, RD rises as the absolute time difference increases to more than 4 h, yielding an OMI-TOMS RD of more than 10% as this difference increases to 8 h. The DOAS-RD may be up to 15%, while GOME-2A RD does not exceed 10%. The satellite total ozone RD may reach.5%, as the distance between the satellite overpass pixel and the station become more than 100 km. Possibly because of the discrepancy in surface albedo, the TOMS-algorithm retrieved total ozone produced underestimation, when the pixel on the south-east side of the station(the Antarctica continent) is used, but overestimation on the north-west side of the station(the Indian Ocean). Consistency between space and ground-based total ozone data is least for the "ozone hole". Typically, the RD of TOMS-algorithm retrieved total ozone is within 1%/10 yr. Thus, the SBUV and Brewer monthly averaged total ozone anomalies from 1996 to 2015 were1%/10 yr and 0.9%/10 yr, respectively. Both indicate slight, but consistent, ozone layer recovery.  相似文献   

8.
It is shown how to retrieve the atmospheric ozone profile by means of ground based microwave measurements of the radiative intensity. Chahine's iteration method is used. The method is tested by a numerical experiment. The retrieval rms about the mean error is approximately 0.4 ppm. The required measurement accuracy for the brightness temperatures is ±0.01 K.  相似文献   

9.
由卫星和航空磁测成果推断中国岩石圈的磁性特征   总被引:11,自引:2,他引:11  
根据前人所得卫星和航磁异常解释结果,作者的综合研究表明:(1)在塔里木、四川和松辽盒地,地壳呈强磁性,至少可分为两层,上层磁化强度为1A/m,下层为2A/m或更强一些。在上述盆地中央,地幔顶部约10km厚,也是强磁性的,此外,在南中国海,地壳和地幔顶部也是强磁性的,卫星磁异常的源位于上述部位。(2)西藏高原,中国东南沿海一带以及其他一些褶皱带之下,地壳是弱磁性的,磁性层在地表以下30km以内,磁化强度约0.66A/m。特别要指出的是,在东南沿海一带,磁性层底面和莫霍面重合,而居里等温面恰在莫霍面之下,因此这个带可能是Wasilewsky PJ等提出的“莫霍面是一个磁性界面”的一例。  相似文献   

10.
The transport mechanisms responsible for the seasonal behavior of total ozone are deduced from the comparison of model results to stratospheric data. The seasonal transport is dominated by a combination of the diabatic circulation and transient planetary wave activity acting on a diffusively and photochemically determined background state. The seasonal variation is not correctly modeled as a diffusive process. The buildup of total ozone at high latitudes during winter is dependent upon transient planetary wave activity of sufficient strength to cause the breakdown of the polar vortex. While midwinter warmings are responsible for enhanced ozone transport to high latitudes, the final warming marking the transition from zonal mean westerlies to zonal mean easterlies is the most important event leading to the spring maximum. The final warming is not followed by reacceleration of the mean flow; so that the ozone transport associated with this event is more pronounced than that associated with midwinter warmings.  相似文献   

11.
The comparative analysis of the Earth’s surface deformations measured by ground-based and satellite geodetic methods on the regional and zonal measurement scales is carried out. The displacement velocities and strain rates are compared in the active regions such as Turkmenian–Iranian zone of interaction of the Arabian and Eurasian lithospheric plates and the Kamchatka segment of the subduction of the Pacific Plate beneath the Okotsk Plate. The comparison yields a paradoxical result. With the qualitatively identical kinematics of the motion, the quantitative characteristics of the displacement velocities and rates of strain revealed by the observations using the global navigational satellite system (GNSS) are by 1–2 orders of magnitude higher than those estimated by the more accurate methods of ground-based geodesy. For resolving the revealed paradoxes, it is required to set up special studies on the joint analysis of ground-based and satellite geodetic data from the combined observation sites.  相似文献   

12.
Résumé On déduit les expressions donnant le géopotentiel et la pesanteur sur un ellipso?de triaxial extérieur, de même que la pesanteur sur la surface de niveaux extérieure et les valeurs moyennes intégrales de ces grandeurs. On discute la convergence des séries et l'usage des formules déduites à la détermination des paramètres de la forme du corps terrestre.

Address: Politickych vězŭů 12, Praha 1-Nové Město.  相似文献   

13.
The possibility of comparing in detail CLUSTER satellite data with data on pulsating spots registered with a TV camera at the Lovozero Observatory when the satellite crossed the magnetospheric region related to the camera’s field of view is discussed. The satellite ionospheric projections were calculated using the T89, T96, and T01 models. It was shown that the projection allows us to judge with confidence whether or not a satellite will find itself in a region of pulsating auroras when only the level of geomagnetic activity and the characteristics of the interplanetary medium are a priori known. When different models are used in the projection, the spread is not less than the characteristic dimensions of the pulsating spots and can be as high as 100 km. The corresponding satellite flight time is ∼4 min. Such a large spatial and time uncertainty does not allow us to compare in detail the satellite data with ground-based optical measurements without a priori information on, e.g., the character of precipitation above a spot, as has been done by other researchers in the case of auroral arcs. The situation becomes even more complex if a satellite is in the region of greatly stretched magnetic field lines.  相似文献   

14.
By means of a meridional chain of 19 stations between Tromso, Norway, and Hermanus, South Africa, a permanent registration of ozone near the ground has been obtained since 1970. From the first year of operation surprisingly systematic annual variations come out, which agree with theoretical calculations on stratospheric-tropospheric exchange.  相似文献   

15.
The mesopause kinetic temperature at an altitude of 87 km measured with a SABER broadband radiometer installed on the TIMED satellite and the hydroxyl molecule rotational temperature measured with a ground-spectrograph installed in high-latitude eastern Siberia (Maimaga optical station; φ = 63°N, λ = 129.5°E) are compared. The data of the observations performed from 2002 to 2006 have been analyzed. The temperatures measured during the satellite passes at distances not larger than 300 km from the intersection of the spectrograph sighting line with the hydroxyl emitting layer (∼87 km) have been compared. An analysis of 130 cases of coincident measurements indicated that the average hydroxyl molecule rotational temperatures are systematically lower than the average kinetic temperature at an altitude of the hydroxyl layer measured with SABER by 4.4 K (with a standard deviation of 11.4 K). A seasonal dependence is observed regarding the difference between the ground-based and satellite measurements. The difference decreases from 10 K in January to zero towards March. However, the time variations in the temperature obtained with the ground-based device and on the satellite are similar. Based on the performed analysis, it has been concluded that a series of hydroxyl rotational temperatures can be used to study temperature variations on different time scales, including long-term trends at the temperature emission altitude (∼87 km).  相似文献   

16.
A commercial version of the prototype New Zealand narrowband interference filter instrument has been run at Garmisch-Partenkirchen since autumn 1977. The vicinity of the Dobson stations Hohenpeissenberg and Arosa permitted a check of the filter instrument's utility, reliability and long-term stability in total ozone measurement by (i) station to station-or short-range intercomparisons of daily means and (ii) a several days' direct intercomparison at Arosa in spring 1978.The regression analysis with the Hohenpeissenberg data-covering the five month autumn-winter 1977/78 period with highly variable ozone-shows that the filter instrument's direct-sun modeX AD total ozone values were systematically too low by a conversion factor of 0.93. The excellent proportionality between the instruments is indicated by the standard deviation of only 1,3%. The (–7.0±1.3%) bias perfectly agrees with the result reported byBasher [1] for a similar, yet direct, intercomparison.During the direct Arosa intercomparison the filter instrument also tracked down short-time variations in a remarkable, though biased, parallelism with the Dobson instruments, and theX AD daily means fit well into the prognostic relationship derived from the preceding autumn-winter short-range intercomparison.A creeping deterioration of the characteristics of the 305.5 nm double filter then prevented any furtherX AD total ozone intercomparison. No final decision is possible whether this behaviour after a half year's run is typical or just an unusual exception. The otherwise excellent long-term stability is demonstrated by the comparison of theX CD daily means with the HohenpeissenbergX AD data for a 1 1/2 year's period (autumn 1977–spring 1979), resulting in the same bias relationship as for theX AD total ozone measurements.  相似文献   

17.
本文基于1979-2014年臭氧总量的卫星遥感数据,利用多元线性回归模型对臭氧总量数据序列进行模拟计算,考察了北太平洋上空臭氧总量长期变化趋势及其影响因素的作用.结果表明,北太平洋地区大气臭氧总量长期变化呈现减少趋势,但是减少速率随季节和纬度带表现出差异性,在各纬度带臭氧峰值季节臭氧下降趋势最为显著.在0°-15°N地区臭氧高值出现在夏秋季节并在8月达到峰值,峰值月份臭氧年均下降率约为0.2DU/a;15°-30°N亚热带地区臭氧高值出现在春夏季并在5月达到峰值,峰值月份臭氧年均下降速率约为0.22DU/a;而在30°-45°N中纬度地区臭氧高值出现在冬春季并在2月达到峰值,峰值月份臭氧年均下降率0.75DU/a.在臭氧分布年平均态基础上,影响臭氧总量分布变化的因素主要有臭氧损耗物质(EESC)、太阳辐射周期(Solar)、准两年振荡(QBO)和厄尔尼诺-南方涛动(ENSO)等.其中,EESC导致臭氧损耗效应随着纬度升高而增大,在从低到高的三个纬度带损耗最大值分别为11DU、16DU和66DU;Solar增强导致臭氧增加,在三个纬度带的增加效应最大值分别为16DU、17DU和19DU;QBO@10 hPa和QBO@30 hPa对臭氧影响幅度基本在±10DU内波动,只有QBO@10 hPa对30°-45°N区域的影响作用达到14DU,值得注意的是QBO影响作用随着纬度变化存在相位差异,在0°-15°N区域臭氧变化与QBO呈现相同相位,而在15°-30°N和30°-45°N区域臭氧变化与QBO呈现相反相位;ENSO对各个纬度带臭氧影响幅度也在±10DU内,ENSO影响作用在不同纬度带也存在相位差异,臭氧总量变化在0°-15°N、15°-30°N区域与ENSO相位相反,在30°-45°N区域与ENSO相位一致.  相似文献   

18.
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   

19.
A scheme of a system of physical and chemical processes controlling the production, transport and destruction of ozone and its gaseous catalysts, as well as other related gases in the low and high stratosphere is presented. An account is made of temperature variations of the stratospheric layer resulting from changes in ozone content; also included is the effect of temperature variations on photochemical reaction rates and ozone and other gases transport between atmospheric layers. Parameters describing major relations of the system are inferred from the analysis of ozone and trace gas data and from the results of model calculations of interdependence between variations in temperature and ozone content of the layer.An analysis of minor fluctuations of the linearized system shows that photochemical processes are responsible for its aperiodic stability and that gas transport between atmospheric layers destabilizes the system.  相似文献   

20.
In order to study the behavior of stratospheric minor constituents related to aeronomic processes and atmospheric transport in the meridional plane, a numerical two-dimensional model is established.This model is applied to the study of chlorine compounds in the stratosphere. A special attention is devoted to the effect in the ozonosphere of an increase of CIX due to anthropogenic activities.  相似文献   

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