郑州地区气溶胶光学厚度反演与分析     

田宏伟  郑有飞  陈怀亮  邓伟  杜子璇 《气象科技》2010,38(4):515-520

利用CE-318太阳光度计,采用Bouguer-Lamber定律,反演郑州地区2008年气溶胶光学厚度,分析该地区气溶胶光学厚度的日变化和月变化特征,并进一步分析天气条件对气溶胶光学厚度的影响。结果表明:2008年郑州地区气溶胶光学厚度与2007年持平,波长指数有所增大。气溶胶光学厚度存在明显的季节变化,春夏高,秋冬低,最低值出现在12月,郑州地区气溶胶光学厚度主要受工业烟尘影响。工作日和非工作日气溶胶光学厚度日变化趋势存在差异,交通负荷的变化可能对气溶胶光学厚度的日变化影响较大。轻雾和霾均能引起气溶胶光学厚度的显著增大,并且轻雾对气溶胶光学厚度的影响大于霾。沙尘过程中,气溶胶光学厚度急剧增大,而后逐渐下降,并逐渐恢复到正常水平,波长指数会减小。  相似文献   

MODIS近红外大气可降水含量与乌鲁木齐地基GPS水汽数据的对比分析   总被引：1，自引：0，他引：1  

崔彩霞  杨青  赵玲  李杨 《沙漠与绿洲气象(新疆气象)》2008,2(1):1-4

本研究在建立HDF数据图像显示、数据提取和分析平台的基础上,利用乌鲁木齐地基的GPS水汽数据,对比分析了2004年6月2日-8月2日之间37d的MODIS近红外大气可降水含量的精度.发现MODIS反演的近红外PW系统性地比GPS探测的PW偏小,但在变化趋势上是相似的,说明MODIS反演的近红外大气可降水含量还是能够反映水汽的变化趋势.37d中降水出现的日期对应于PW的大值日期,尤其与GPS的大PW日数非常吻合.MODIS近红外大气柱可降水含量能够提供大面积水汽空间分布数据.每天一次的水汽分布数据能够用于研究水汽的时空分布和气候特征.该研究开发的MODIS水汽数据分析处理平台也可应用于其它MODIS反演产品的分析,如地表面温度、气溶胶光学厚度等.  相似文献   

利用台站资料定标太阳光度计效果评估   总被引：4，自引：1，他引：3  

李霞 《气象科技》2009,37(1):79-84

运用Langley方法、采用法国CE318太阳光度计在台站的观测记录为光度计定标,提出一种较客观的数据处理方法,主要分为4步：①利用Langley法对全年资料进行预处理,得到各通道定标常数、Langley法线性拟合相关系数、550nm的气溶胶光学厚度等;②以线性拟合相关系数的阈值大小（如440nm相关系数大于等于0．99）、定标期间550nm的平均气溶胶光学厚度小于等于0．15、半天（上午或下午）参与拟合的数据个数大于等于8组为条件,对预处理数据进行筛选;③根据光度计电压信号图像、最大值再次选取定标常数;④对最终选出的多组定标常数取平均值。对2002、2005年,乌鲁木齐、塔中、哈密、和田4个站点光度计资料进行试验,定标系数与出厂定标值（2002年）、北京定标值（2005年）比较后,4个站点的定标误差基本控制在8．5％以内（和田除外）,说明这种定标步骤有一定的参考价值。  相似文献   

Geochemical behaviour of the Tunisian background aerosols in Sirocco wind circulations     

Chafai AZRI  Habib ABIDA  Khaled MEDHIOUB 《大气科学进展》2009,26(3):390-402

This study examines spatial and time evolutions of the principal constituents of the Tunisian background aerosols under Sirocco wind circulations. Aerosols coming from the Sahara Desert were found to be loaded with particulate matter, especially silicon. The aerosols were shown to have varying geochemical behaviour along the ``South-North" displacement of the Saharan plumes, depending on the wind flow characteristics, geomorphologic features and the nature of soils swept by the wind. In the south and the center part of the country, the transfer of aerosol constituents to the soil (by gravity and/or impaction) was probably predominated by localized enrichment phenomena. The latter are reinforced by the effect of turbulent winds over bare soils, wind wakes and probably selective disintegration, especially in the vicinity of the geomorphologic features of central Tunisia. These relatively high features, extending over important distances, appear to be of paramount importance for the phenomena of redistribution of aerosol constituents even during periods without Sirocco wind circulations. In the northern section of the country, aerosol constituent concentrations dropped to almost 50%, in spite of the abundance of localized turbulent winds. This may be explained by the effect of forests and the relatively dense vegetation cover, which clearly reinforces the transfer phenomena to the soil and the attenuate of dust entrainment.  相似文献   

江西千烟洲气溶胶光学厚度的反演与分析   总被引：2，自引：0，他引：2  

袁海军  顾行发  陈良富  余涛  刘强  李小文 《遥感学报》2006,10(5):762-769

2005年10-11月份，中国科学院遥感应用研究所联合北京师范大学遥感中心等几家单位在江西千烟洲地区进行了为期30天的遥感实验，在实验期间，采用法国CIMEL公司研制的太阳分光光度计CE318进行了连续测量，得到了大量的大气光学数据。利用这些数据，反演了气溶胶光学厚度和相应的Angstrom参数，分析了光学厚度和Angstrom参数的日变化和逐日变化，并讨论了这些变化的原因。本文还讨论了在反演气溶胶光学厚度过程中可能的误差源。  相似文献   

Indo-Japanese Lidar Observations of the Tropical Middle Atmosphere During 1998 and 1999     

Y. BHAVANI KUMAR  C. NAGESWARA RAJU  M. KRISHNAIAH 《大气科学进展》2006,23(5):711-725

A state-of-the art Rayleigh and Mie backscattering lidar was set up at Gadanki (13.5N, 79.2E) in the Tropics in India. Using this system, regular observations of upper tropospheric clouds, aerosols at stratospheric heights and atmospheric temperatures in the range from 30 to 80 km were made. In this paper, the data collected during the period of 1998–99 were selected for systematic investigation and presentation. The Mie scattering lidar system is capable of measuring the degree of depolarization in the laser backscattering. Several tropical cirrus cloud structures have been identified with low to moderate ice content. Occasionally, thin sub-visible cirrus clouds in the vicinity of the tropical tropopause have also been detected. The aerosol measurements in the upper troposphere and lower stratosphere show low aerosol content with a vertical distribution up to 35 km altitude. Rayleigh-scattering lidar observations reveal that at the tropical site, temperature inversion occurs at mesospheric heights. Atmospheric waves have induced perturbations in the temperatures for several times at the upper stratospheric heights. A significant warming in the lower mesosphere associated with a consistent cooling in the upper stratospheric heights is observed particularly in the winter season during the events of sudden stratospheric warming (SSW).  相似文献   

Mineral aerosol： Connections to climate and human health     

Richard Arimoto 《中国地球化学学报》2006,25(B08):220-220

Mineral dust is a major component of the global aerosol, and the importance of dust for regional climate and biogeochemical cycles has become increasingly apparent. By scattering and absorbing radiant energy and through their effects on clouds, dust and other aerosol particles can cause climatic effects that affect ecosystem function and human health. Iron oxide minerals in the atmosphere are especially important in this regard because they absorb solar radiation and are involved in redox reactions. Furthermore, dust particles that settle out of the atmosphere provide nutrients, including iron, to marine ecosystems and other nutrients to terrestrial ecosystems. New technologies have shown that dust reacts in complex ways with other atmospheric constituents; indeed, this is one of the major revelations of recent dust research. Dust and other substances commonly occur in the same air parcels, but bulk chemical methods do not show whether the particles are internally mixed （multiple components mixed in single particles） or externally mixed （admixtures of different particles）. Electron beam techniques have shown internal mixtures of dust and black carbon, but the implications of this for climate forcing are still unresolved. Studies conducted with an aerosol time-of-flight mass spectrometer suggest preferential reactions between dust, sulfur and nitrogen oxides, and chlorine. These reactions have important implications for particle formation and solubility, and for the particles＇ health effects. The activity of radionuclides, including Pu, co-vary with atmospheric dust loads, and while this is not a serious health concern, the emerging view is that pure dust is rarely sampled. While dust can affect ecosystems through climate, the production of dust also is influenced by humans, especially land-use practices that affect vegetative cover. Indeed, the issue of the relative importance of natural vs. anthropogenically-driven changes in dust budgets remains a subject of debate although several recent studies indicate natural variability dominates.  相似文献   

华北地区层状云微物理特性及气溶胶对云的影响   总被引：27，自引：3，他引：27  

黄梦宇  赵春生  周广强  段英  石立新  吴志会 《南京气象学院学报》2005,28(3):360-368

利用机载粒子探测系统(PMS,ParticleMeasurementSystem)对1990年9、10月和1991年4月的春秋两季层状云进行了云及降水的微物理特征探测,分析了云微观特征和垂直分布,初步探讨了气溶胶对云的影响。结果表明,华北地区层状云的基本特征为云滴数浓度79.2cm-3、液态含水量0.03g.m-3、有效直径11μm并有垂直差异;云下气溶胶数浓度与云滴数浓度两者之间存在正相关关系,但其定量关系还有待于进一步研究。  相似文献   

浑善达克沙地沙尘气溶胶的辐射强迫   总被引：5，自引：7，他引：5  

成天涛  吕达仁  徐永福 《高原气象》2005,24(6):920-926

利用2001年春季浑善达克沙地外场观测的辐射资料及大气辐射模式,对沙尘气溶胶的局地辐射强迫进行了分析和模拟估算。计算结果表明,浑善达克沙地大气透过率日变化显著,晴天可达0.80以上,沙尘天气最低在0.01以下;白天沙尘的辐射强迫对地表有冷却作用,夜间起保温作用。观测期间,平均大气透过率为0.6,白天沙尘对地面向下长波辐射的平均强迫增加量为16.76 W.m-2,对地面净辐射能收支的平均强迫减少量为62.76 W.m-2;夜间地表长波辐射净损失量因沙尘作用减少,平均为67.84 W.m-2。  相似文献   

1984～2000年印度洋与中国地区上空对流层中上层及平流层气溶胶变化和输送特征   总被引：4，自引：2，他引：4       下载免费PDF全文

王开存李维亮  白立杰 《应用气象学报》2004,15(1):32-39

利用美国SAGE II (Stratospheric Aerosol and Gas Experiment II)卫星最新版（6.0版）1.020 μm通道逐日气溶胶消光系数资料，得出了对流层中上层及平流层（10 km以上高度）气溶胶光学厚度的平均分布和变化特征。结果表明:气溶胶光学厚度在低纬度大，在印度洋的岛屿上空有三个高值中心，气溶胶光学厚度高值中心与对流层中上层的上升气流的高值中心相对应。与17年(1984～2000年)年平均相比，近6年（1995～2000年）孟加拉湾至青藏高原东南部上空气溶胶光学厚度明显增加；中国东部地区上空气溶胶光学厚度增加，中西部地区则减小。气溶胶光学厚度存在三个经向的增加带和两个经向的减小带。中纬度与赤道之间的布鲁尔-多普森环流（Brewer-Dobson Circulation）带来的低层大气与对流层中上层及平流层之间的气溶胶输送是导致气溶胶这种经向一致变化的主要因素。气溶胶的这种输送产生的近地面大气污染物向中上层大气输送有可能产生重要的气候变化。  相似文献