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WZ index is an aggregated indicator of air pollution, that encompasses the joint impact of various meteorological elements on pollution (sulphur dioxide) concentration level. Following meteorological elements were taken into account: mean daily air temperature, wind speed at the height of 10 m above the ground level at the time 12 UTC, precipitation, atmospheric air pressure and existence of lower inversion layer. The most often the maxima of WZ index correlate in time with appearance of maxima in air pollution in Decembers, Januaries and Februaries.
This work shows description of the state of air pollution by sulphur dioxide and nitrogen dioxide in different air mass on Ursynów WULS station. There are two main purposes in this work. First purpose is to calculate the value of SO2 and NO2 concentration in station Ursynów WULS in dependence on infl owing air mass. Second purpose is to calculate the relations between concentration of SO2 and NO2 in the air and some basic meteorological elements such as air temperature and relative humidity, wind velocity and rain fall. The studies covered the period of April 2001 to September 2006.
Popularization of automatic methods of measuring meteorological elements and substituting manual methods creates a problem of maintaining homogeneity of measurement series. In such situations it is necessary to conduct measurements simultaneously, i.e. using a method being introduced and a former method. The analysis of measurement series carried out simultaneously enables comparing and relating measurements made by a new apparatus to already existing results. The present paper includes the results of the analysis of differences between daily, monthly and seasonal atmospheric precipitation values coming from a 11-year series of simultaneous measurements with a telepluviometer and the Hellmann rain gauge.
In this paper, monthly precipitation sums, measured at Ursynów WULS – SGGW station in the period 1960–2009 were analysed. The coeffi cient of the variability of yearly precipitation sums was calculated and the linear trend of yearly precipitation sums was examined. The method of Kaczorowska (1962) was applied to classify months and years in respect of precipitation quantity. A detailed analysis was performed also on daily maximum precipitation sums for years 1980–2009. The probability of maximum daily precipitation occurrence was calculated for various intervals of the precipitation and for different seasons of the year.
The Biebrza River valley is the most valuable wetland’s complex in Poland. The biodiversity of endangered plants and animals observed in this region is outstanding. The lower river valley is considered as one of the most natural wetland area in Europe since, only small reach of this valley was drained. The conservation of this valuable object depends also on maintaining of high soil moisture, therefore the knowledge about the water balance dynamic of this ecosystem seems to be crucial. The evaporation process is a common element of both water and heat cycles thus wetland surface heat balance studies will be helpful for modeling of local hydrological conditions. The paper presents the methodology of grassland ecosystem heat balance structure research which have just started at the Biebrza River valley. The automatic measurement system was developed at the Division of Meteorology and Climatology, and it is consisted of net radiometer – net radiation measurement, heat fl ux plates – soil heat fl ux density measurement, 3D sonic anemometer used for direct measurement of sensible heat fl ux (eddy covariance approach). Two thermohygrometers were installed additionally, which allow to estimate the latent heat flux density using the Bowen ratio method.
This study is based on a 50-year data series (1964-2013) of total solar radiation (G) from the Kołobrzeg – station that is located on the Polish Baltic Sea coast and is characterised by a very high level of air quality. To find and remove gross errors, quality control checking procedures were applied in this study. Additionally, the homogeneity of the G series in this study has been tested on a monthly basis by using of the Standard Normal Homogeneity Test for single shifts. We found a statistically non-significant decrease in G during the period from 1964 to 2013. The decrease in the 5-year mean total solar radiation is evident from the beginning of the 1980s, with the minimum mean value occurring in the second half of the 1990s, while G slightly increased from the early 2000s. The analysis of seasonal G patterns shows that total solar radiation in summer is the most similar to the annual pattern and only the summer series trend shows a statistically significant decrease in G. We have also found two noticeable tendencies in monthly anomalies of G over the studied decades; they are negative trends in May and August. The shape of the decadal daily G histogram remained unchanged during the analysed decades.
In this paper, an attempt is made to characterize PM₁₀ imission field in the area of Warszawa with regard to PM content of the metals As, Cd, and Ni. Particulate matter concentration measurements were performed within this agglomeration with the use of many measuring methods, different not only in respect of the sampler operation rules, but also of the accuracy, sampling frequency, and separation of the particulate matter fractions. Since 1 October 2003, Warszawa agglomeration has had an extended measurement network consisting of 4 automatic stations and 7 manual ones. This paper attempts to estimate the influence of the prevailing meteorological conditions on PM₁₀ imission and also to determine those parameter groups that enable the best description of monthly and seasonal variability of particulate matter. The data considered in this paper were collected in 2004-08. Based on the performed analysis, it could be concluded that air quality in the area of Warszawa agglomeration is still unsatisfactory. The main cause of high PM concentration in Warszawa is the dynamic development of vehicular traffic and ever-increasing number of cars; both factors cause the PM concentration to be several times higher. The second important source of particulate matter in the Warszawa area is so-called “low emission”, occurring in the heating season, generated mainly by the processes of combustion in the communal and housing sectors. In 2004-08 the meteorological conditions prevailed 22.4% to 76.2% of the decadal variability of PM concentration in the individual months and 9.5% to 56.8% of seasonal variability. The most significant influence of the meteorological conditions was during the winter, especially in January. The regression analysis has found evidence for statistically vital relationships of PM₁₀ concentration and meteorological parameters, especially maximum air temperature, wind speed, and precipitation. Research on the chemical composition of PMs presented in this paper confirms that the target values of arsenic, cadmium, and nickel concentration in PM₁₀, determined by Directive 2004/107/WE, were not exceeded at the network stations in 2006-08 and the recorded concentration of these heavy metals were low. Analyzing the tendency of air quality changes for the last five years in the area of Warszawa, it was found that there was danger of not complying with the requirements set by the European Union. The time limit by which the member countries have to adjust the PM₁₀ concentration limits in their territories to the EU norms is June 2011.
Celem pracy było określenie zmienności stężenia zanieczyszczeń gazowych (NO2 i SO2) i pyłowych (PM10) w zależności od warunków opadowych, oraz próba ustalenia empirycznej zależności skuteczności wymywania pyłu zawieszonego od natężenia, czasu trwania i wielkości opadu atmosferycznego. Skuteczność wymywania (∆S) obliczano jako ubytek stężenia pyłu, spowodowany opadem atmosferycznym, wyrażony w % zawartości pyłu przed wystapieniem opadu. W pracy wykorzystano średnie dobowe i średnie 1-godzinne wartości stężenia zanieczyszczeń gazowych (NO2 i SO2) i pyłowych (PM10) ze stacji monitoringu powietrza na Ursynowie (MzWarszUrsynow) z lat 2004-2007 oraz dobowe i 1-godzinne sumy opadów atmosferycznych ze stacji MzWarszSGGW należącej do Zakładu Meteorologii i Klimatologii SGGW. Zaprezentowane wyniki świadczą o wpływie opadów atmosferycznych na zmniejszenie zanieczyszczenia atmosfery – szczególnie pyłem zawieszonym PM10. Otrzymane zależności w postaci równań regresji prostej należy traktować głównie jako statystyczny wskaźnik roli opadów, który z pewnością nie przesądza o ich ilościowej skuteczności. Analiza dotycząca ustalenia empirycznej zależności wymywania pyłu zawieszonego PM10 od natężenia, czasu trwania i wysokości opadu atmosferycznego wykazała, że istnieje słaba, istotna statystycznie, korelacja pomiędzy skutecznością usuwania pyłu z powietrza a czasem trwania opadu i sumą opadu, a uzyskana zależność w postaci równania prostej tłumaczy ok. 10% zmienności (∆S).
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