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1.
我院承担了该专题的2个子专题:“南极冰雪与大气相互作用过程和辐射特征的观测研究”和“南极臭氧和紫外辐射的监测和变化机制研究”。1999年的研究进展如下:1)对南极中山站用Brewer臭氧光谱仪观测得到的1993-1998年臭氧总量和紫外辐射的分析结果表明,春季出现臭氧低于200  相似文献   

2.
利用Brewer臭氧分光光谱仪对青藏高原东北部瓦里关地区的大气臭氧柱总量及太阳紫外B生物有效辐射剂量进行了连续的观测。通过对1996-1996年的资料分析表明:该地区的臭氧柱总量具有明显的年季变化特征,并存在着减少的趋势,与TOMS卫星的观测结果相一致;臭氧垂直廓线的Umkehr反演得出这一地区的臭氧数密度最大值出现在20-30km处,冬春季的高度低于夏季;太阳紫外B生物有效辐射剂量夏季最高可达0.4W/m^2。  相似文献   

3.
张凤英  董超华 《气象》1988,14(10):22-24
本文介绍了利用NOAA系列卫星垂直探测器(TOVS)资料反演水汽廓线的方法,并给出了利用特征向量回归法由NOAA-9 TOVS资料反演水汽廊线的结果及其与常规探测资料的比较分析。比较结果表明,卫星反演水汽廓线与常规探测水汽廓线基本吻合。  相似文献   

4.
李俊  曾庆存 《大气科学》1997,21(2):214-222
前文给出了卫星红外观测资料的反演处理方法,并对方法作了理论上的分析,在本文中,我们将此方法应用到TOVS、GOES-8实际资料及AIRS模拟观测资料处理中并重点对TOVS资料进行试验。在反演中,我们将大气温度廓线和水汽混合比(lnq)廓线用各自的经验正交函数(EOF)表示以提高反演的稳定性并缩短计算时间,同时采用一种过滤操作以加速迭代的收敛速度。除了用本文提出的方法对TOVS资料进行处理外,还用国际TOVS处理软件包(ITPP-4.0)对同样的资料进行反演。试验表明,本文方法的反演结果优于ITPP的结果。AIRS模拟反演结果表明,高分辨率红外垂直探测器的遥感精度能够达到温度1 K、水汽10%。  相似文献   

5.
利用NOAA-9垂直探测资料反演地面气温的初步试验   总被引:1,自引:0,他引:1  
张凤英 《气象》1987,13(11):23-27
本文主要介绍利用多重线性回归技术,由垂直探测资料(TOVS)反演地面气温的方法,给出了利用1986年8月22—24日的NOAA—9 TOVS资料的试验结果,并与常规观测的百叶箱温度进行比较,结果表明:对60—20°N、75—150°E范围,总平均绝对偏差为2.8℃。  相似文献   

6.
1990~2002年北京地区大气臭氧垂直分布Umkehr观测反演研究   总被引:4,自引:0,他引:4  
基于标准Umkehr反演算法, 利用北京地区Dobson仪器逆转观测资料, 反演计算出臭氧垂直分布.在反演过程中加入气溶胶订正因子, 使反演结果更加合理.利用臭氧垂直分布反演结果, 研究1990~2002年北京地区臭氧垂直分布特征和变化情况.结果表明在1992年秋季和1993年春季期间, 在10.3~23.5 km范围内臭氧浓度有较大幅度降低, 造成了这个期间月平均臭氧总量的明显偏低; 1990年到2002年期间, 臭氧总量的变化呈现出缓慢下降趋势, 但不同高度臭氧含量的变化趋势有所不同.  相似文献   

7.
南极臭氧洞的影响因子和变化趋势   总被引:1,自引:0,他引:1       下载免费PDF全文
利用卫星和台站观测的南极臭氧资料和NCEP/NCAR再分析资料,分析了南极臭氧近年来的变化特征和影响因子,探讨了南极臭氧洞期间中山站臭氧突变过程与大气动力的作用。结果显示,平流层氯和溴的卤化物当量(EESC)和平流层温度是影响南极臭氧洞面积的关键因子。臭氧总量与EESC和平流层温度均具有显著相关,表明两站虽然都位于臭氧洞边缘,EESC和平流层温度对臭氧总量的变化仍然可以起决定性的作用,同时也验证了EESC参数在东南极大陆沿岸具有适用性。 EESC的年代际变化与臭氧变化趋势相似,臭氧的年际变化与平流层温度关系密切。回归结果表明,2010年后臭氧洞面积逐渐减小,在2070年左右可能恢复到1980年前的水平,但其结果存在很大的不确定性。  相似文献   

8.
华北强天气的水汽图象特征研究   总被引:1,自引:0,他引:1       下载免费PDF全文
利用1991~1993年共37个时次的NOAA TOVS反演的红外水汽亮度温度图、卫星云图及常规气象资料,分析华北地区夏季强天气过程,归纳出降水和强对流天气的水汽图象4种基本类型,为分析和预报此类天气提供了新的依据。  相似文献   

9.
云参数对RTTOV5模式模拟误差的影响分析   总被引:3,自引:0,他引:3       下载免费PDF全文
该文根据1998年8月的业务TOVS反演的温度、水汽垂直廓线资料以及其它资料, 利用RTTOV5模式模拟NOAA14极轨气象卫星上相应红外探测 (HIRS) 通道的辐射亮温值, 将模拟值对比实测TOVS探测资料, 结果表明, 晴空模式模拟亮温与实测值的误差小于部分有云时的误差, 模拟误差受云的影响呈反相变化, 对水汽敏感的中低层探测通道在晴空时的误差小于部分有云情况; 通过对比白天和夜间短波窗区探测通道模拟误差, 分析了其受地面反射太阳光辐射的影响的大小及其原因所在; 并利用RTTOV5的伴随模式和Jacobine模式分析了模式模拟误差对初始场云参数的敏感性。该研究为TOVS/ATOVS探测资料在3DR或4DR变分同化中的直接应用奠定了基础。  相似文献   

10.
首次在测站稀少的高原地区引入经变分技术处理的 TOVS卫星资料 ,通过动力诊断探讨了解决高原地区测站少、数值预报模式初始场信息误差大的技术关键问题 ,提出了采用TOVS反演资料在高原地区增加模式初始场信息的构思 ,并应用变分法处理 TOVS反演资料 ,显著地提高了高原初始场信息的可靠性 ;并从动力诊断分析角度 ,进一步证实了 TOVS反演资料的应用有利于提高高原动力系统特征的描述能力 ,并显著改善水汽输送通道分布及其层结稳定度等有关初始场信息的客观性  相似文献   

11.
Brewer 分光光度计遥感大气臭氧垂直廓线的研究   总被引:1,自引:0,他引:1       下载免费PDF全文
利用建立的球面分层大气散射模式,研究了Brewer仪器工作波长进行Umkehr短法反演所包含的信息量,给出Brewer仪器探测大气臭氧垂直廓线的方法。同时,用气溶胶光学厚度计算得到气溶胶订正系数,建立了Umkehr反演的程序,用此程序对TableMountain资料进行气溶胶修正,得到了较好的结果。对北京测站1991年1─3月资料进行由气溶胶造成的臭氧反演廓线的误差计算,结果表明,用常规反演方法得到的各层臭氧含量的误差与平流层气溶胶光学厚度有一近似线性的关系;进行气溶胶修正后,与国外的臭氧反演廓线的误差修正工作 ̄[1]比较,结果较一致。研究提出的气溶胶订正反演方法为更好地对平流层臭氧变化趋势进行研究提供了可能性和可靠的基础。  相似文献   

12.
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   

13.
14.
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   

15.
拉萨地区1998年夏季臭氧总量及垂直廓线的观测研究   总被引:13,自引:4,他引:9       下载免费PDF全文
该文根据1998年6~10月上旬在拉萨地区进行的臭氧总量及臭氧垂直廓线的观测结果, 并结合同期同纬度其他两个臭氧站数据资料, 证实了以拉萨地区为代表的青藏高原在夏季存在“臭氧低谷”的现象.分析表明, 地基和卫星观测的臭氧总量有一定误差. Umkehr观测反演结果表明夏季拉萨地区平流层臭氧分布和同纬度其他地区相比略有不同; 在对流层, 探空资料显示了该地区对流层臭氧有低值分布的特征.  相似文献   

16.
Abstract

Spectrometers are designed to isolate particular wavebands and suppress light from wavelengths outside the band of interest. However, a small amount of undesired light will always enter the detector, not through the designed optical path, but through random scattering from the instrument optical components, housing, and dust particles. Every spectrophotometer has stray light coming from outside the nominal measurement waveband. For Dobson spectrophotometers and single monochromator Brewer spectrophotometers, which are basic instruments in the World Meteorological Organization (WMO) ozone and ultraviolet (UV) monitoring network, the error introduced by stray light is substantial when the ozone slant path becomes very large because of high solar zenith angles and a thick ozone layer. These are common conditions during Arctic spring. To study the issue, a long ozone slant path Intercomparison/Calibration campaign for Nordic Brewers and Dobsons was held at Sodankylä 8–24 March 2011 and a follow-up campaign to extend calibrations to shorter ozone slant paths took place at Izaña observatory, Tenerife, between 28 October and 18 November 2011. These campaigns were part of the Committee on Earth Observation Satellites (CEOS) Intercalibration of Ground-based Spectrometers and Lidars project funded by the European Space Agency (ESA), intended to permit the homogenization of ozone data from the European ozone ground-truthing network. During the active intercomparison periods, measurements were taken only when good conditions for sun or moon observations existed. Laboratory measurements using calibration lamps and helium-cadmium (HeCd) lasers were an essential part of both campaigns. The campaigns produced a high-quality database of total ozone and UV measurements and an accurate, up-to-date calibration and characterization of participating Brewers and Dobsons against the European standard instruments from the Regional Dobson Calibration Centre-Europe (RDCC-E) and the Regional Brewer Calibration Centre-Europe (RBCC-E). In the present work we focus on single monochromator Brewers and present a physics-based method to compensate for the stray-light effects in ozone retrieval using laboratory characterizations and radiative transfer modelling. The method was tested with independent data from the campaign.  相似文献   

17.
云对中国区域卫星观测臭氧总量精度影响的检验分析   总被引:5,自引:0,他引:5  
郑向东 《大气科学》2008,32(6):1431-1444
根据卫星和地基观测, 比较了我国香河、 昆明、 瓦里关和龙凤山四个站点臭氧总量自1979年以来的变化。卫星与地基观测的臭氧总量长期趋势比较一致, 表明臭氧总量均有下降趋势, 但是卫星与地基各自观测的结果仍存在着显著的差别。为研究卫星与地基臭氧总量的差别, 以地基观测臭氧总量为参考, 检验云对历史TOMS (Total Ozone Mapping Spectrometer) 和GOME (Global Ozone Monitoring Experiment) 臭氧总量精度的影响。结果显示: 云 (云量或云顶高度) 增加了卫星臭氧总量误差, 降低数据精度。随着地面云量的增加, TOMS、 GOME臭氧总量相对误差在上述四个地点呈现明显的上升趋势 (瓦里关最为明显), 但最大变化幅度没有超过2.0%。TOMS臭氧总量相对误差随地面云量变化呈现区域性特点, 香河与龙凤山 (代表着中纬度高臭氧总量区域)、 昆明与瓦里关 (代表中、 低纬度高原低臭氧总量区域) 分别为两个变化特点接近的区域。GOME臭氧总量相对误差与云之间关系的区域特征不明显。利用卫星遥测FRESCO (Fast Retrieval Scheme for Clouds from the Oxygen A\|band) 云信息检验GOME卫星臭氧总量精度的表明, 只有当云量大于5成后GOME臭氧总量才显示出相对误差增加的现象, 但无明显趋势; 随着FRESCO云顶高度的增加, GOME臭氧相对误差在香河、 瓦里关均呈现明显的上升趋势并有3%左右幅度的变化。TOMS臭氧总量相对误差随着地面有效反射率的增加而增大, 且误差幅度超过2%; TOMS\|N7臭氧总量比TOMS\|EP约高2.0%~3.0%。分析还表明, 云内和云以下臭氧柱浓度在反演的卫星臭氧总量中的贡献很可能被高估了。  相似文献   

18.
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   

19.
Sixteen years (1994 – 2009) of ozone profiling by ozonesondes at Valentia Meteorological and Geophysical Observatory, Ireland (51.94° N, 10.23° W) along with a co-located MkIV Brewer spectrophotometer for the period 1993–2009 are analyzed. Simple and multiple linear regression methods are used to infer the recent trend, if any, in stratospheric column ozone over the station. The decadal trend from 1994 to 2010 is also calculated from the monthly mean data of Brewer and column ozone data derived from satellite observations. Both of these show a 1.5 % increase per decade during this period with an uncertainty of about ±0.25 %. Monthly mean data for March show a much stronger trend of?~?4.8 % increase per decade for both ozonesonde and Brewer data. The ozone profile is divided between three vertical slots of 0–15 km, 15–26 km, and 26 km to the top of the atmosphere and a 11-year running average is calculated. Ozone values for the month of March only are observed to increase at each level with a maximum change of +9.2?±?3.2 % per decade (between years 1994 and 2009) being observed in the vertical region from 15 to 26 km. In the tropospheric region from 0 to 15 km, the trend is positive but with a poor statistical significance. However, for the top level of above 26 km the trend is significantly positive at about 4 % per decade. The March integrated ozonesonde column ozone during this period is found to increase at a rate of ~6.6 % per decade compared with the Brewer and satellite positive trends of ~5 % per decade.  相似文献   

20.
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   

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