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1.
Stray light in single-monochromator Brewer instruments increases the uncertainty of solar ultraviolet spectral irradiance measurements and ozone retrievals. To study how spectral irradiance within and outside the measurement ranges of the instruments affects stray light, two Brewer MKII instruments were characterized for the level of in- and out-of-range stray light at multiple laser wavelengths. In addition, several solar-blind filters utilized in single-monochromator Brewers to limit out-of-range stray light were characterized for spectral and spatial transmittances. Finally, the measurement results were used to simulate the effect of stray light and stray light correction on spectral irradiance and ozone measurements at different wavelength regions. The effect of stray light from wavelengths above 340?nm was found to be negligible compared with other sources of uncertainty. On the other hand, contributions from wavelengths between 325 and 340?nm can form a significant portion of the overall stray light of the instrument, with 325?nm being the upper limit of the nominal measurement range of the instrument.  相似文献   

2.
Comparisons of total column ozone measurements from Dobson, Brewer and SAOZ instruments are presented for the period 1990 to 1995 at seven stations covering the mid- and the high northern latitudes, as well as the Antarctic region. The main purpose of these comparisons is to assess, by reference to the well established Dobson network, the accuracy of the zenith-sky visible spectroscopy for the measurement of total ozone. The strengths and present limitations of this latter technique are investigated. As a general result, the different instruments are found to agree within a few percent at all stations, the best agreement being obtained at mid-latitudes. On average, for the mid-latitudes, SAOZ O3 measurements are approximately 2% higher than Dobson ones, with a scatter of about 5%. At higher latitudes, both scatter and systematic deviation tend to increase. In all cases, the relative differences between SAOZ and Dobson or Brewer column ozone are characterised by a significant seasonal signal, the amplitude of which increases from about 2.5% at mid-latitude to a maximum of 7.5% at Faraday, Antarctica. Although it introduces a significant contribution to the seasonality at high latitude, the temperature sensitivity of the O3 absorption coefficients of the Dobson and Brewer instruments is shown to be too small to account for the observed SAOZ/Dobson differences. Except for Faraday, these differences can however be largely reduced if SAOZ AMFs are calculated with realistic climatological profiles of ozone, pressure and temperature. Other sources of uncertainties that might affect the comparison are investigated. Evidence is found that the differences in the air masses sampled by the SAOZ and the other instruments contribute significantly to the scatter, and the impact of the tropospheric clouds on SAOZ measurements is displayed.  相似文献   

3.
比较分析了2017年南极中山站3种仪器测量地面太阳紫外B(UVB)波段和紫外A(UVA)波段的辐照度。以Brewer光谱仪测值为参考,国产宽波段FSUVB日射表在UVB(波段280~315 nm)的辐照度相对误差为(55±75)%,误差随大气臭氧总量的增加呈上升趋势,但在南极“臭氧洞”期间偏低。Yankee UVB宽波段日射表在UVB(波段280~320 nm)的辐照度相对误差为(-31±22)%;国产宽波段FSUVA日射表在UVA(波段315~400 nm)的辐照度相对误差为(23±5.9)%。太阳天顶角低于80°的晴天以Tropospheric Ultraviolet Visible(TUV)辐射模式计算结果为参考时,FSUVB,Yankee UVB和FSUVA辐照度的平均相对误差分别为(30±37)%,(-22±19)%和(27±6.4)%,而Brewer相对误差未超过3.5%。国产宽波段UV日射表测值偏高,反映出波长较长的杂散光对太阳辐照度测值影响明显。  相似文献   

4.
南极春季臭氧的TOVS反演及其与BREWER观测的比较   总被引:1,自引:1,他引:1       下载免费PDF全文
通过改进臭氧的统计反演算法,从NOAA卫星的TOVS资料中提取了1993年南极臭氧洞期间中山站上空大气臭氧含量的资料。本文的结果与NOAA的TOVS臭氧产品以及中山站的Brewer观测进行了比较。尽管3种资料对在臭氧洞期间臭氧含量的显著减少这一特征上相当一致,但此项结果相对于Brewer观测,其均方根误差29 DU,优于NOAA的业务反演产品。此外,还初步讨论了这两种反演的误差特征。  相似文献   

5.
Based on the AIRS satellite spectrometer data (the Aqua platform), the peculiarities are studied of the field of total ozone (TO) under prolonged blocking conditions over the European part of Russia in summer 2010. It is revealed that the spatial distribution of TO values during the period of blocking was characterized by negative TO anomalies (up to -37 DU on the first ten days of August) over the western and northern peripheries of the blocking anticyclone and by positive TO anomalies (up to 60 DU) over the troughs adj oinmg the anticyclone. Possible mechanisms of the formation of TO anomalies are discussed. The results are presented of the validation of TO measurements with the AIRS spectrometer in May-September 2010 obtained from the data of TO measurements with Brewer spectrophotometers at Kislovodsk and Obninsk stations of the global ozone network.  相似文献   

6.
Abstract

Regular ground-based measurements of total ozone are available over the full Russian territory using M-124 filter ozonometers, Brewer spectrophotometers, and Système d'Analyse par Observation Zénithale (SAOZ) spectrometers in the Arctic region where these observations are essential for evaluating ozone loss in winter. Daily measurements are performed by three Brewer spectrophotometers; these are located in Kislovodsk (43.7°N, 42.7°E), Obninsk (55.1°N, 36.6°E), and Tomsk (56.5°N, 85.1°E). Two SAOZ spectrometers are deployed at the Arctic Circle in Salekhard (66.5°N, 66.7°E) and Zhigansk (66.8°N, 123.4°E). In addition, regular winter–spring ozonesonde soundings are carried out in Salekhard. Altogether, they have provided the unique measurements over the eastern Arctic required for characterizing ozone loss during each winter and will also monitor the anticipated ozone recovery following the reduction of chlorine and bromine ozone-depleting substances in the atmosphere.  相似文献   

7.
大气臭氧变化在全球气候和环境中具有重要作用,是当今大气科学领域的重要研究对象之一。对比分析了中国科学院大气物理研究所河北香河大气综合观测试验站2014~2016年Dobson和Brewer两种臭氧总量观测仪器探测结果的一致性,并使用1979~2016年Dobson观测数据分析了香河地区臭氧总量的长期变化趋势。结果表明:进行有效温度修正后,两种臭氧总量仪器观测结果一致性较好,平均偏差仅为-0.14DU(多布森单位),平均绝对偏差为8.00 DU,标准差为36.09 DU,相关系数达0.964。整体来说,两类仪器观测臭氧总量吻合较好。SO2浓度对Dobson仪器数据精度有一定影响,两组仪器数据在SO2浓度为0~0.2DU、0.2~0.4DU和0.4DU大气条件情况下的平均偏差分别为4.8 DU、7.0 DU和8.0 DU,平均偏差随SO2浓度升高而增大。过去38年香河地区的臭氧总量季节差异性强,春、冬两季臭氧总量高,夏、秋两季臭氧总量相对低,季节变化趋势差异明显。从长期变化上看,臭氧总量变化波动有不同的周期,在4个大的时间段变化趋势不同,2000~2010年臭氧层有显著恢复,但最近几年又有变薄的趋势。  相似文献   

8.
Abstract

Ground‐based measurements of total ozone were made during the polar night from Arctic stations in the winters of 1987–88 and 1988–89. The measurements were made with automated Brewer ozone spectrophotometers using the moon as a light source. Data were obtained from Alert and Resolute in Canada for both winters and from Heiss Island, USSR, for the second winter. The method of measurement is briefly reviewed and data from the three stations are presented. The ground‐based total ozone measurements are compared with the integrated values derived from ozonesonde profiles.  相似文献   

9.
本文选取多个臭氧总量观测站点,采用"三重制约法"分别对下列3组仪器观测臭氧总量数据进行统计分析,解算出不同观测资料的误差标准差,进而对比研究各种仪器的精度特征:1)1996~2003年期间地基WOUDC(World Ozone and Ultraviolet Radiation Data Centre)观测网络仪器(包括Brewer、Dobson和Filter臭氧测量仪)与星载TOMS(Total Ozone Mapping Spectrometer)和GOME(The Global Ozone Monitoring Experiment)仪器;2)2004~2013年期间WOUDC与星载OMI(ozone monitoring instrument)和SCIAMACHY(scanning imaging absorption spectrometer for atmospheric chartography)仪器;3)2004~2013年期间地基SAOZ(Système D’Analyse par Observations Zénithales)与星载OMI和SCIAMACHY仪器。结果表明,1996~2003年期间TOMS V8和GOME观测精度相当,分别为7.6±2.8 DU/46(其中,7.6±2.8 DU为所分析站点观测资料的平均精度及其标准差,46为站点数目)和7.6±1.5 DU/46。TOMS V8观测精度优于TOMS V7(8.5±3.0 DU/46),验证了前者对后者有所改进。2004~2013年期间OMI和SCIAMACHY在WOUDC地基站点观测精度接近,分别为6.6±1.4 DU/21和6.0±1.6 DU/21。SAOZ地基仪器精度为8.4±3.6 DU/8。对于3类WOUDC地基仪器,Brewer站点观测资料的平均精度最优(7.9±3.3 DU/12),Dobson次之(8.7±2.3 DU/19),Filter最差(14.7±4.0 DU/15)。相比于卫星,3种地面仪器观测平均精度较差(10.5±4.3 DU/46),这主要是由于Filter精度较差引起。中国境内的瓦里关(Brewer)、香河(Dobson)和昆明(Dobson)3个地基站点仪器观测精度均较优,分别为7.8 DU、6.7 DU和6.6 DU。尽管不同站点之间存在一定差异,但整体来说,地基与卫星仪器在中国境内3个站点观测臭氧总量吻合较好。  相似文献   

10.
An intercomparison campaign was conducted at the Observatoire de Haute Provence (OHP) in Southern France in September 1989 in order to compare the three instruments used for vertical tropospheric ozone profiling in the European TOR (Tropospheric Ozone Research Project) network: balloon borne ECC and Brewer-Mast sondes and a ground based UV-DIAL (DifferentialAbsorptionLidar). Additionally, a stratospheric lidar system and the Dobson spectrophotometer of the OHP were operated. Seven simultaneously measured vertical ozone profiles gave evidence for systematic differences of 15% between both types of electrochemical sondes in the troposphere, the Brewer-Mast sondes reading the smaller ozone values. These differences might be explained on the one hand by a possible contamination of the ozone sensor with reducing substances, causing a negative bias mainly for Brewer-Mast sondes and, on the other hand, by the evolution of the sonde background current during the flight, causing a positive bias for ECC sondes and a negative bias for Brewer-Mast sondes. The tropospheric lidar system, measuring the vertical ozone distribution between 6 and 12–15 km, showed ozone concentrations intermediate between the sonde results. This is in good agreement with its estimated systematic error of better than 7% in the upper troposphere. In the stratosphere, the differences between electrochemical sondes and the lidar are between 5 and 10% before the normalisation with the total ozone values measured by the Dobson spectrophotometer, and always below 5% after. While the Dobson normalisation thus corrects rather well the stratospheric part of the sonde profile, it only partially reduces errors occurring in the troposphere.  相似文献   

11.
Solar ultraviolet radiation at the surface has been measured at Potsdam on cloudless days by spectrometer OL 752/10. The measurements are compared with broad-band filter measurements and with model calculations using a modified version of Green's model, which is independent of the measurements. Input data to the model such as atmospheric ozone and aerosol optical thicknesses were measured by a Dobson and Brewer spectrophotometer as well as a Linke Feussner pyrheliometer, respectively. Differences between the model and the measurements are discussed in terms of uncertainties in the calibration and errors of instruments as well as uncertainties in the model calculations including the errors of input data. It is demonstrated that different chemically and biologically effective radiances can be determined from only one set of measured spectral irradiance components, i.e. global radiation and diffuse downward and upward directed radiation. Examples of diurnal variations of the photochemical production of ozone and hydroxyl radicals as determined from spectral irradiance measurements and measured concentrations of relevant trace gases are given.It is shown from the measured irradiance that relations between different effects of radiation to the biosphere depend on solar zenith angle, and to a certain extent also on atmospheric ozone. This has to be taken into account when adverse effects of changing UV radiation are evaluated. Radiation Amplification Factors derived from measurements correspond to those determined from model calculations.  相似文献   

12.
《大气与海洋》2013,51(4):315-324
Abstract

Column ozone data collected using a Brewer spectrophotometer at Vanscoy, Saskatchewan during the Middle Atmosphere Nitrogen Trend Assessment (MANTRA) balloon campaign (Strong, this issue) were reduced using an improved analysis algorithm. The retrieved total ozone values are compared with those from other instruments and good agreement was found. The aerosol optical depth has also been calculated using the same set of data and the results are presented. Periods of an increased aerosol optical depth coincide with periods when plumes of smoke from nearby forest fires reached the campaign site.  相似文献   

13.
The well calibrated Brewer spectrophotometer 17 (Sci-Tec Instruments Inc., Canada) stayed at the Meteorological Observatory Hohenpeissenberg (MOHP) from August 27 until September 1, 1984, in order to check and recalibrate Brewer 10, which had some stability problems. Brewer 17 was initially calibrated in July 1983, the validity of this calibration was repeatedly verified before and after the stay at the MOHP (Kerr et al., 1985; Kerr, 1984). The instrument proved itself to be very stable and appropriate as travellings standard instrument.As Dobson 104 didn't seem to be well calibrated at that time, the occasion was taken to perform also a Dobson recalibration. The methods normally used were not satisfactory, but a different method, presuming Effective Absorption Coefficients (EAC), presented by Kerr et al. at the Quadrennial Ozone Symposium 1984 in Greece, yielded encouraging results. Before recalibration Dobson 104 showed a difference of 2–3% in comparison to Brewer 10-, Brewer 17- and TOMS- (on satellite Nimbus 7) measurements, whereas the agreement with the Brewers after EAC-calibration was good (X rel < 1%). The different Dobson calibration methods are compared and the results of the Dobson 104 and Brewer 10 recalibrations are presented.
Zusammenfassung Vom 27. August bis 1. September 1984 befand sich das Brewer Standard Spektrophotometer 17 (Sci-Tec Instruments Inc., Canada) am Meteorologischen Observatorium Hohenpeißenberg (MOHP), um den nicht sehr stabilen Brewer 10 zu überprüfen und neu zu kalibrieren. Der Brewer 17 wurde erstmals im Juli 1983 kalibriert, die Gültigkeit dieser Eichung wurde mehrfach vor und einmal nach dem Aufenthalt am MOHP bestätigt (Kerr et al., 1985; Kerr, 1984). Das Instrument erwies sich als sehr stabil und geeignet als transportables Standardinstrument.Da der Dobson 104 zum damaligen Zeipunkt ebenfalls nicht gut kalibriert schien, wurde die Gelegenheit einer Dobson-Neukalibrierung wahrgenommen. Die normalerweise benutzten Methoden waren nicht zufriedenstellend im Gegensatz zu einer Methode, die von Effektiven Absorption Coeffizienten (EAC) ausgeht. Diese von Kerr et al. auf dem Quadrennial Ozon Symposium 1984 in Griechenland vorgestellte Methode lieferte hier ermutigende Ergebnisse. Vor der Neueichung zeigte der Dobson 104 eine Differenz von etwa 2–3% im Vergleich mit Brewer 10-, Brewer 17- und TOMS- (auf dem Nimbus-7-Satelliten) Messungen, während die Übereinstimmung mit den Brewer-Geräten nach der EAC-Kalibrierung gut war (X rel < 1%). Die verschiedenen Dobson-Kalibrierungsmethoden werden verglichen und Ergebnisse der Dobson 104- und Brewer 10-Neukalibrierungen werden vorgestellt.
  相似文献   

14.
国产臭氧探空仪观测数据质量分析   总被引:2,自引:1,他引:2       下载免费PDF全文
对国产臭氧探空仪从2001年4月到2004年9月在北京观测的臭氧垂直分布数据的质量进行分析。对国产臭氧探空仪系统基本测量数据(包括电化学反应池池温、臭氧最大分压及其所在的高度、对流层顶的温度和高度)进行初步分析, 结果发现国产臭氧探空仪的稳定性仍需进一步提高。与地面多谱森臭氧总量观测相比, 国产臭氧探空积分的总量普遍要高,2002年至2003年之间的差别范围基本上保持在±20%以内。与国际普遍使用的双池型电化学(ECC型)臭氧探空观测结果相比, 国产臭氧探空观测臭氧分压在15 km以下、25~30km两个高度范围, 均要高于ECC测值。分析结果建议国产臭氧探空仪应尽快参与由全球大气本底监测(GAW)技术主持的世界臭氧探空仪标定中心进行标定, 并在现有的技术条件下, 向双池型电化学型臭氧探空仪这一方向发展  相似文献   

15.
《大气与海洋》2013,51(4):325-338
Abstract

A portable ground‐based instrument has been constructed for the automated measurement of vertical column abundances of a number of gases pertinent to stratospheric ozone chemistry. The instrumentation is described in this paper and results are presented from the first set of field measurements, made during the Middle Atmosphere Nitrogen TRend Assessment (MANTRA) 1998 field campaign at Vanscoy, Saskatchewan, Canada. Zenith‐sky spectra in the near ultraviolet and visible wavelength regions were recorded for a period of seven days, prior to and following the launch of the MANTRA balloon on 24 August 1998. The spectra were then analysed using the differential optical absorption spectroscopy (DOAS) technique in conjunction with a radiative transfer model to determine vertical column amounts of ozone and NO2. Ozone measurements compared favourably with concurrent observations by ozonesondes, a Brewer spectrophotometer, and satellite instruments. Vertical NO2 columns were in broad agreement with those determined by the Global Ozone Monitoring Experiment (GOME) satellite instrument.  相似文献   

16.
Abstract

On the basis of two well‐known ozone‐weather relationships, an algorithm is proposed that estimates total ozone amounts using readily available meteorological information. The technique has been labelled METOZ from Meteorological Total Ozone. A rationale and derivation of the technique is presented.

METOZ total ozone amounts were generated for Toronto and Edmonton locations and compared with ground‐based Brewer spectrophotometer measures for these two stations in the Canadian ozone monitoring network for data from January to April 1989. Per cent differences between METOZ and Brewer total ozone measurements were calculated and are presented.

This mid‐latitude wînter metoz algorithm was also used to produce a hemispherical total ozone field for 16 March 1986, which was compared with the corresponding TOMS data to demonstrate other potential applications of the technique.  相似文献   

17.
Data of stratospheric ozone measurements with the AK-3 lidar over Obninsk in 2012–2015 are compared with Aura/MLS and Aura/OMI satellite data and parallel surface observations of total ozone (TO) with the Brewer spectrophotometer. The maximum difference in mean ozone concentration between the lidar and Aura/MLS data in the altitude range of 13 to 32 km does not exceed 0.2 x 1012 mol./cm3 (or the maximum of 9% at the altitude of 13 km). At the same time, Aura/OMI data have a positive bias of about 20% relative to lidar data in the range of 13 to 20 km that is associated with OMI measurement errors according to literature data. Total ozone values calculated from lidar measurements jointly with the known climatology data are compared with those measured with the Brewer spectrophotometer. It is demonstrated that the correlation between the results of measurements obtained by two methods is close to linear, and the mean relative difference in the overall measurement range does not exceed 5%.  相似文献   

18.
Abstract

The influence of variations in atmospheric temperature and ozone profiles on the total ozone column (TOC) derived from a Brewer MKII spectrophotometer operating in Thessaloniki, Greece, is investigated using three different sets of ozone absorption cross-sections. The standard Brewer total ozone retrieval algorithm uses the Bass and Paur (1985) cross-sections without accounting for the temperature dependence of the ozone cross-sections which produces a seasonally dependent bias in the measured TOC. The magnitude of this temperature effect depends on the altitude where the bulk of the ozone absorption occurs. Radiosonde measurements for the period 2000 to 2010 combined with climatological ozone profiles were used to calculate the effective temperature of ozone absorption and investigate its effect on the retrieved ozone column. Three different ozone absorption cross-section spectra convolved with the instrument's slit function were used: those of Bass and Paur (hereafter BP), currently used in the standard Brewer retrieval algorithm; those of Brion, Daumont, and Malicet (Malicet et al., 1985; hereafter BDM); and the recently published set by Serdyuchenko et al. (2013 hereafter S13). The temperature dependence of the differential ozone absorption coefficient ranges between 0.09 and 0.13% per degree Celsius for BP, between ?0.11 and ?0.06% per degree Celsius for BDM, and between 0.018 to 0.022% per degree Celsius for S13, resulting in a seasonal bias in the derived TOC of up to 2%, 1.8%, and 0.4%, respectively. The temperature sensitivity of the differential ozone absorption coefficient for the Brewer spectrophotometer at Thessaloniki for the BP and BDM cross-sections is found to be within the range reported for other Brewer instruments in earlier studies, whereas the seasonal bias in TOC is minimized when using the new S13 cross-sections because of their small temperature dependence.  相似文献   

19.
根据Dobson和TOMS资料分析北京和昆明大气臭氧总量变化特征   总被引:11,自引:0,他引:11  
用约20年 Dobson和TOMS资料来分析北京(39.93°N,116.40°E)和昆明 (25.02°N,102.68°)两地大气臭氧总量的变化特征,结果表明:(1)在1979-2000年间北京大气臭氧长期变化趋势是-0.642 DU/年,而昆明在1980-2000年间的趋势是-0.009 DU/年;(2)北京和昆明两地大气臭氧都有很强的季节内变化(尤其冬季更强),与季节性变化强度相当;(3)在北京和昆明,由记录较短的大气臭氧资料分析得到的长期变化趋势,与较长记录得到的结果有显著差异;(4)在北京(中纬度)和昆明(低纬度)大气臭氧都有显著的准两年振荡信号;(5)两个站点大气臭氧的年际变化主要由长期趋势项和准两年振荡信号组成;(6)Dobson仪测量得到的臭氧总量与TOMS资料非常一致。  相似文献   

20.
中国4个地点地基与卫星臭氧总量长期观测比较   总被引:1,自引:0,他引:1       下载免费PDF全文
对我国河北香河、云南昆明、青海瓦里关及黑龙江龙凤山地基观测臭氧总量与不同时期、不同卫星反演的产品差别特点进行比较,评估地基和卫星观测臭氧总量数据的质量信息以及近30年来我国不同区域臭氧总量的变化趋势特征。结果表明:4个站点的地基与卫星观测臭氧总量的绝对和相对差别分别为-5~10 DU和-5%~4%;日平均相对差别基本上呈现随机分布特征。TOMS算法反演的卫星臭氧总量与地基差别总体上要优于与DOAS算法反演的同期产品。地基与卫星臭氧总量差别呈明显的区域特点,可能反映了卫星反演计算中所需的臭氧、温度垂直分布等初始条件的纬度分布差异对卫星产品精度的影响。在过去30年,4个站点的臭氧总量在经历1993年前的显著降低后于1995—1996年逐渐回升,而瓦里关站在2001年前后的回升更为明显。  相似文献   

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