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901.
The data are presented on total nitrogen dioxide (NO2) content in the atmosphere from 1979 to 2009 at the high-mountain scientific station located in the unpolluted area in the North Caucasus at the height of 2070 m above the sea level (43.7° N, 42.7° E). The total content of NO2 was measured on the basis of attenuation of direct solar radiation over slope pathways after the sunrise and before the sunset. Characteristics features are analyzed of temporal variability of total NO2 content in the atmosphere related to its diurnal and seasonal variations, 11-year solar activity, volcanic eruptions, quasi-biennial oscillations of tropical circulation, and the El Niño effect.  相似文献   
902.
The results of numerical simulation of downward solar radiation fluxes for background and smoke-contaminated atmospheric conditions are discussed. Vertical profiles of aerosol characteristics are obtained from the empirical model based on the data of aircraft sounding of profiles of angular scattering coefficients and content of absorbing particles in the lower troposphere. The background model was created using the results of measurements obtained under cloudless and mostly cloudless atmospheric conditions in 1999–2011. Optical parameters of smoke aerosol are determined from the data of aircraft measurements in the period of long-term wildfires in Siberia in the summer 2012. It is demonstrated that deficiency in diurnal values of total solar radiation at the surface level caused by the formation of the optically dense smoke layer as compared to background conditions, is more than 13 MJ/m2.  相似文献   
903.
The critical comments to the publications by the authors ofthe present paper that were given in [10] (the publications deal with the possible effects of gravity field inhomogeneities in the atmosphere and ocean) are discussed. In the authors' opinion, some remarks are groundless. At the same time, the authors agree with one of the important remarks that the results of their paper concerning studies of the ocean disturbances are to be reconsidered.  相似文献   
904.
The spatial distribution of methane content and methane fluxes in the water in the north-western part of the Sea of Japan, in the Kuril basin of the Sea of Okhotsk, and in the near-Kuril part of the Pacific Ocean is studied using the data of marine research expeditions in 2005, 2010, and 2011. The studies revealed the significant variability of the methane flux depending on the source presence and on the sea surface conditions. The high emission of methane from water to the atmosphere is registered in the areas where its concentration exceeds the equilibrium values with the atmosphere. The use of the model of computation of the fields of currents and contaminant transport for the investigated water area enabled explaining the formation of the high concentration of methane in the center of vortices in the zones of sea water convergence in the water areas under study.  相似文献   
905.
Average long-term fields of geopotential gradients in the middle and upper troposphere and temperature gradients and geopotential Laplacian in the middle troposphere in the Northern Hemisphere in winter are analyzed. Based on the analysis of the distribution of the maximum values of gradients, the average long-term position of upper-level frontal zones and their axial lines was determined. Their spatial distribution is analyzed from the point of view of interaction between thermobaric fields over different regions of the globe. Average long-term parameters of upper-level frontal zones in the middle troposphere are presented. Average long-term fields of wind speed in the middle and upper troposphere are investigated. It is demonstrated that the zones of the maximum values of wind speed agree well with the position of separated upper-level frontal zones.  相似文献   
906.
选取2008—2012年贵州省3646站次的辐射雾天气过程,根据08时能见度大小将其划分为4级雾、3级雾、2级雾和1级雾四个等级,利用常规地面观测资料分析其时空变化特征,并根据辐射雾多发生区选取出修文、三穗和凤冈3个分布在贵州省高速干道上的站点,利用相应地面气象观测台站的逐日逐时实测气象要素资料,分析其不同等级的气象要素特征。结果表明:各等级辐射雾在10月—次年1月发生较多;空间分布呈"东多西少"格局,4级雾主要分布中心为修文和岑巩,其余等级辐射雾主要分布中心为三穗、凤冈、平塘、正安、松桃和锦屏;修文站的4级雾偏多与其平均相对湿度明显偏高、风速小于3 m/s和风向主要为偏东风相关性较高;三穗站和凤冈站的平均相对湿度与当日08时和前一日20时的气温差相对利于雾的生成,但其风速较小,垂直混合较弱,故其主要为较低等级雾。  相似文献   
907.
对济南市2013年1—12月的能见度、相对湿度、PM10及PM2.5逐时监测数据分析,结果表明:能见度、相对湿度、PM10和PM2.5浓度有明显的月变化和日变化规律。在各项污染物中,能见度与颗粒物的相关性最高,与PM10的相关系数为-0.6718,与PM2.5的相关系数为-0.7422;在气象因子中,与相对湿度的相关性最高,相关系数为-0.6501。不同季节条件下,能见度与PM2.5的相关性明显优于PM10的,冬季能见度与颗粒物的相关性明显优于其他季节的。  相似文献   
908.
马宁  谢均  郭军  何群 《气象科技》2016,44(3):400-407
使用1981—2013年6—8月的月平均海河流域站点降水资料以及NCEP/NCAR再分析资料,采用SVD方法分析了北半球高度场环流异常与海河流域夏季降水的关系。结果表明夏季海河流域的一致型降水异常主要受热带地区高度场异常的影响,而北半球中高纬的高度异常分布对海河流域东南部降水异常有重要作用。热带及中高纬地区的高度场异常与副热带西风急流和流域上空的水汽输送有一定的对应关系,急流强度和位置的变化以及水汽辐合异常造成海河流域降水异常,尤其中高纬高度异常的这种对应关系更加明显,并且两个地区的高度异常分布对应的海河流域异常水汽输送有不同来源。  相似文献   
909.
Based on the global aerological dataset and on the method for determination of the boundaries and amount of cloudiness using the profiles of temperature and humidity obtained from the atmospheric radiosounding data [23], the estimates are computed for the parameters of atmospheric temperature- humidity separation into cloud and intercloud layers from the surface to the height of 10 km. The base and top of cloud layers and their total thickness and frequency are selected as layering parameters. The computations are based on the data for the observational period of 1964-1998. To specify the spatiotemporal features of atmospheric layering, long-term geographic distributions of mean values and standard deviations of the mentioned parameters are constructed for January and July, and the amplitude of their variations is determined.  相似文献   
910.
Investigated is the periodic component of geoacoustic emission within the frequency band from 2.0 to 6.5 kHz registered by the piezoceramic hydrophone installed near the bottom of Lake Mikizha in the Kamchatka Peninsula. It is revealed that the variation period is 24 hours and the maximum variation is observed in summer, when the average daily air temperature is above 10°C. In that period the close connection is revealed between the series of air temperature and geoacoustic emission. Taking into account the similar results of measurements of the ground surface slope at the observation site, the most probable reason for the diurnal variations of high-frequency geoacoustic emission is the deformation of near-surface sedimentary rocks caused by diurnal variations of temperature.  相似文献   
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