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1.
Seasonal and Diurnal Variation of Surface Ozone and a Preliminary Analysis of Exceedance of its Critical Levels at a Semi-arid Site in India 总被引：1，自引：0，他引：1
Gur Sumiran Satsangi A. Lakhani P. R. Kulshrestha A. Taneja 《Journal of Atmospheric Chemistry》2004,47(3):271-286
The mixing ratios of surface O3 were measured at St. John's College, Agra, an urban and traffic influenced area for the period of 2000–2002. The monthly
averaged O3 mixing ratios ranged between 8 to 40 ppb with an annual average of 21 ppb. Strong diurnal and seasonal variations in O3 mixing ratios were observed throughout the year except for monsoon season. The mixing ratios of O3 follow the surface temperature cycle and solar radiation (r = 0.72 and r = 0.65 with temperature and solar radiation, respectively). Concentrations were higher with winds associated with NE and
NW direction indicating the impact of pollution sources on surface O3 concentration. Exceedance of ozone critical level was calculated using the AOT 40 index and found to be 840 ppb.h and 2430
ppb.h for summer and winter seasons, respectively. The present O3 exposures are lower than the critical level of O3 and suggest that the present level of O3 does not have any impact on reduction in crop yields. 相似文献
2.
Nidhi Verma Aparna Satsangi Anita Lakhani K Maharaj Kumari 《Journal of Earth System Science》2018,127(3):42
In the present study, measurements of surface ozone (\(\hbox {O}_{3}\)) and its precursors (NO and \(\hbox {NO}_{2}\)) were carried out at a sub-urban site of Agra (\(27{^{\circ }}10'\hbox {N}\), \(78{^{\circ }}05'\hbox {E}\)), India during May 2012–May 2013. During the study period, average concentrations of \(\hbox {O}_{3}\), NO, and \(\hbox {NO}_{2}\) were \(39.6 \pm 25.3\), \(0.8 \pm 0.8\) and \(9.1 \pm 6.6 \, \hbox {ppb}\), respectively. \(\hbox {O}_{3}\) showed distinct seasonal variation in peak value of diurnal variation: summer \({>}\) post-monsoon \({>}\) winter \({>}\) monsoon. However, \(\hbox {NO}_{2}\) showed highest levels in winter and lowest in monsoon. The average positive rate of change of \(\hbox {O}_{3}\) (08:00–11:00 hr) was highest in April (16.3 ppb/hr) and lowest in August (1.1 ppb/hr), while average negative rate of change of \(\hbox {O}_{3}\) (17:00–19:00 hr) was highest in December (–13.2 ppb/hr) and lowest in July (–1.1 ppb/hr). An attempt was made to identify the \(\hbox {VOC--NO}_{\mathrm{x}}\) sensitivity of the site using \(\hbox {O}_{3}/\hbox {HNO}_{3}\) ratio as photochemical indicator. Most of the days this ratio was above the threshold value (12–16), which suggests \(\hbox {NO}_{\mathrm{x}}\) sensitivity of the site. The episodic event of ozone was characterized through meteorological parameters and precursors concentration. Fine particles (\(\hbox {PM}_{2.5}\)) cause loss of ozone through heterogeneous reactions on their surface and reduction in solar radiation. In the study, statistical analyses were used to estimate the amount of ozone loss. 相似文献
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A. N. Fakhrutdinova V. V. Gur’yanov A. Yu. El’kin 《Izvestiya Atmospheric and Oceanic Physics》2006,42(1):60-67
The distributions of kinetic energy (KE) and available potential energy (APE) in the lower and middle atmosphere of the Northern and Southern hemispheres over the period 1992–2003 are investigated. Annual mean values of the amplitude and phase of annual and semiannual oscillations in the zonal and eddy forms of KE and APE are calculated in the height range 0–55 km (1000–0.316 hPa) for the 21st layer. A clearly pronounced annual cycle of the zonal and eddy components of KE and APE with maxima in the winter season are observed in the troposphere of both hemispheres. In the lower stratosphere, the annual-cycle maximum is shifted toward the summer season because of the meridional gradient of the zonal mean temperature. In the stratosphere of both hemispheres, along with annual oscillations, semiannual oscillations are present in all forms of energy. The intensity of these oscillations for the zonal KE and APE at the upper-stratosphere heights is comparable to the intensity of annual oscillations. A local structure of the energy regime of the upper mesosphere-lower thermosphere is investigated against the background of the global energy regime from the data of meteor sounding in Kazan. It is shown that, for both the global and regional regimes, specific features of the phase profiles of energy characteristics can be explained by the presence of barriers during the propagation of wave disturbances along the vertical. 相似文献
5.
S. V. Emelina K. G. Rubinshtein V. V. Gur’yanov Yu. P. Perevedentsev A. V. Ivanov 《Russian Meteorology and Hydrology》2015,40(12):838-843
Studied are the effects that variations of meteorological parameters at different time scales in Naberezhnye Chelny city produce on people suffering from ischemic heart disease. The number of ambulance calls from 2010 to 2012, meteorological parameters, and some biometeorological indices are compared by the cross-correlation analysis. Demonstrated is the absence of statistically significant correlation between the daily series of ambulance calls due to ischemic heart disease during the period under study, on the one hand, and average daily series of major meteorological parameters and the most frequently used biometeorological indices, on the other hand. Revealed is the correlation between the number of ambulance calls and the intradaily variations of air pressure and air temperature at the time scale of 3 hours. Proposed is a parameter (biometeorological index of weather effects, IWE) taking into account the total effects of intradaily variations of air pressure and air temperature and characterized by statistically significant correlation with the number of ambulance calls made by people suffering from ischemic heart disease. 相似文献
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A. N. Didenko V. A. Gur’yanov A. Yu. Peskov A. N. Perestoronin D. V. Avdeev E. V. Bibikova T. I. Kirnozova M. M. Fugzan 《Russian Journal of Pacific Geology》2010,4(5):398-417
A model of the formation of the Ulkan trough was specified on the basis of new geochemical and geochronological data. The
volcanics of the Ulkan Group exhibit geochemical features typical of the rocks of two modern geodynamic settings: suprasubduction
and within-plate ones. The combination of the components derived from the different-depth sources in the magmatic chambers
explains the formation of the volcanics with mixed geochemical signatures. The age of the granitoids of three phases of the
Ulkan Massif is determined within the range of 1730–1925 Ga. The granites of the first and third phases have positive ɛNd(T)
of + 3.5 and + 0.7, respectively. The granites of the first phase of the Ulkan Complex were likely derived from the Paleoproterozoic
juvenile crust with an age of 1.84–1.95 Ga. The effusive rocks of the Ulkan Group were presumably formed in a geodynamic setting
of a Cordilleran-type transform continental margin. Judging from the model TNd(DM) age, these geodynamic conditions operated >1.84 Ga ago. 相似文献
8.
Static analysis of stiffened shells has been carried out using an eight-noded isoparametric element for the shell and a three-noded curved beam element for the stiffener. A same displacement function is used for the shell and the stiffener elements. A modified technique has been followed to analyse the shell, which is an improvement over the degenerated shell concept. The stiffness matrix of the curved beam element is generated irrespective of its position and orientation within the shell element. The stiffness matrix of the stiffener is then transferred to all the nodes of the shell element. Numerical examples of stiffened shells with concentric and eccentric stiffeners have been analysed and the results presented together with those available in published literature. 相似文献
9.
Yu. P. Perevedentsev A. A. Vasil’ev K. M. Shantalinskii V. V. Gur’yanov 《Russian Meteorology and Hydrology》2017,42(7):461-470
The spatiotemporal variability of surface air pressure and surface air temperature in the Northern Hemisphere troposphere in 1990-2014 is described. In 2005 the low-frequency component (LFC) of average air temperature in January averaged over the latitude zone of 32.5°-67.5° N has stopped its increase that lasted for 35 years (from 1970). The LFC of air temperature in July has continued growing since 1975 (for 39 years). The anomalies of air pressure and air temperature for thirty-year periods and the dynamics of LFC of air temperature and air pressure in the atmospheric centers of action are analyzed. 相似文献
10.
The large (more than 200000 km2) Uchur-Maya Meso- and Neoproterozoic intracontinental basin is delineated for the first time in the southeastern Siberian Platform, including the territory overlapped by the Ediacaran to Cambrian plate complex. The tectonic elements of higher orders—uplifts, domes, and deeps formed during the Neoproterozoic and Late Mesozoic tectonomagmatic activity—are outlined. The tectonic nappes of Paleoproterozoic rocks from 200 to 400 m thick were established between the Calymmian and Ectasian to Stenian rocks in the southeastern portion of the basin. The thickness of sedimentary rocks increases toward the Yudoma-Maya Aulacogen. The considerable thickness of Meso- and Neoproterozoic rocks and bitumen contents in sedimentary rocks are favorable factors testifying to the petroleum resource potential of the basin. The southern part of the basin is promising for ore deposits (primarily, uranium and gold) in zones of structural and stratigraphic unconformities and within the sedimentary cover itself. This study may serve as a background for further, more detailed tectonic investigations and substantiation of strategic lines of geological exploration. 相似文献