Long range transport of aerosols

Ph.D. - Doctoral Progra

The use of nuclear techniques in source apportionment studies, exemplified by recent studies in Turkey

Nuclear analytical methods are very important atmospheric tools as they provide multielement data, which is essential for receptor modeling. In this study, the application of receptor modeling is discussed on rural data to determine source regions affecting chemical composition of aerosols in the Eastern Mediterranean. The factor analysis revealed 4 sources, two of which represent anthropogenic component in aerosol mass. The source regions that determine the composition of particles is investigated using trajectory statistics

Forest Declie Evidence in Southern Turkey and its possible dependence on ozone trends

During the period between 1991 and 1997, crown condition was monitored at an experimental forest located in Southern Turkey, near Antalya. In order to determine the nutritional status of the stands in the study area, in the years 1992, 1993 and 1998, young and old needles were collected from the labelled trees and nutrient contents (N, P, K, Ca, Mg) of the needles were determined. Between the years 1991 and 1997, the degree of defoliation of the canopies, according to the damage indexes, changes from 10–25% to 25–60%. Between the years 1992 and 1998, examination of nutrition condition of the stands reveal that, sufficient and balanced nutrition status of the trees in the year 1992, becomes insufficient or unbalanced for P, K, and N in 1998.From October 1994 to January 1996, a continuous hourly ozone sampling was performed on the Mediterranean coast of Turkey (30.34°E, 36.47°N) near Antalya. The survey carried out in the summer of 1995 reveals that AOT40f index is 14.612 ppm.h, which exceeds the critical level of 10 ppm.h. As the measured ambient ozone levels are higher than critical level, it has been proposed that ozone may be one of the anthropogenic stress factors causing the forest decline in Southern Turkey observed within this study

Akdeniz ve Karadeniz’deki kirletici Düzeylerini etkileyen kaynak bölgelerinin Belirlenmesi.

Potential source regions of trace elements and major ions measured in the Mediterranean atmosphere were investigated by combining trajectory statistics with emission data reported in the literature. The frequency of air mass transport from different wind sectors was investigated at three selected sites in the eastern Mediterranean, western Mediterranean and Black Sea basins. The upper air mass movements showed fairly similar general features at all three sites, with very small eastern, southeastern and southern components. In all three sites, the dominant flows were from the western, northwestern and northern sectors. Although the general features of the upper air climatology were fairly similar in the western Mediterranean, eastern Mediterranean, and the Black Sea, there were small differences in the flow patterns in each subregion. There were small but statistically significant differences between summer and winter flow patterns. However, these differences were not large enough to explain the consistent seasonal differences in the concentrations of trace elements and major ions reported in the literature. The potential source regions of elements and ions were determined taking into account the residence times of air masses eventually reaching the three sub-basins and emissions. The potential source regions affecting pollutant concentrations in the western Mediterranean are distincly different from the source regions affecting the eastern Mediterranean and Black Sea atmospheres. The comparison of potential source regions with those determined experimentally demonstrated that the wet and dry depositions of pollutants during transport from their source regions to the three sub-basins have a profound influence on their observed concentrations in the receptor areas

Temporal variability of atmospheric trace element concentrations over the eastern Mediterranean Sea

Concentrations of elements and ions measured in aerosol samples collected between March 1992 and December 1993 were investigated to understand temporal variability of elemental concentrations. Collected samples were analyzed by atomic absorption spectrometry, instrumental neutron activation analysis, ion chromatography and colorimetry for approximately 40 elements and major ionic species. Concentrations of elements were found to vary greatly on time scales ranging from days to seasons. Short-term variations in the concentrations of pollution-derived elements are explained by transport from source regions. Short-term variations in the concentrations of sea-salt and crustal elements, on the other hand, are due to the episodic nature of wind-induced particle generation mechanisms. Transport failed to explain long-term variations due to lack of seasonal changes in air mass transport patterns. The seasonal variations in the concentrations of anthropogenic elements are determined by the wet deposition of particles, which is more extensive in the wet season, and distances between source regions and the sampling site. The long-term variations in the concentrations of crustal and sea-salt elements are explained by seasonal changes in their source strengths. Distant rains on the path of the air masses which transport anthropogenic particles to the eastern Mediterranean are more influential on the observed seasonal behavior of pollution-derived elements than local rain events

Source apportionment of trace elements in the Eastern Mediterranean atmosphere

Concentrations of elements and ions, measured in aerosol samples collected during 1993 were investigated to identify sources and source composition of aerosols in the Eastern Mediterranean atmosphere. The factor analysis have shown that Eastern Mediterranean aerosol is a four-component system, including a crustal component, long-range transported pollution component, a marine component and a local pollution component. Main anthropogenic component, which reaches to the region by long-range transport accounts for 70%-90% of the concentrations of Zn, Se, NO3-, nss-SO42-, NH4+ and smaller fractions of V, Sb, Cr and Mn concentrations. According to the quantitative analysis of local and Saharan dust components, the most promising marker elements to distinguish Saharan dust from local soil were found to be Cr, Nd, Mg and Cs as they have significantly different compositions in the local soil and Saharan dust

Atmospheric trace element and major ion concentrations over the eastern Mediterranean Sea: Identification of anthropogenic source regions

Concentrations of elements and ions measured in aerosol samples collected from March 1992 to the end of December 1993 were investigated to identify source regions affecting chemical composition of aerosols in the eastern Mediterranean atmosphere. Collected samples were analyzed for approximately 40 elements and ions using a combination of atomic absorption spectrometry, instrumental neutron activation analysis, ion chromatography and colorimetry. Statistical techniques, such as enrichment factors and a non-parametric bootstrapped potential source contribution function, were applied on the data set to determine main source types and source regions of anthropogenic particles in the eastern Mediterranean basin. Source regions of two previously defined anthropogenic components, namely a long-range transported component and a local pollution component, were identified. The main source areas for pollutants reaching the eastern Mediterranean basin were determined as southern and western parts of Turkey, central and eastern regions of Ukraine, east of Belarus, Greece, Georgia, Romania, coastal areas along France and Spain and coastal areas around the Black Sea, Russia. More distant source regions in the South of UK and Sweden, the central part of Algeria, the northeastern part of Turkey, Russia, Germany, Hungary, Czech Republic, Bosnia and Herzegovina, and coastal areas of Egypt, Israel and Italy do affect aerosol composition in the eastern Mediterranean, but transport from these regions cannot account for the highest 20% of the measured pollutant concentrations

Comparison of Source Regions Affecting SO42- and NO3- Concentrations at the Eastern Mediterranean and Black Sea Atmospheres

In this study, source regions of atmospheric sulfate and nitrate in rural areas at the Black Sea and the Mediterranean coasts of Turkey are compared. Stations on the Black Sea and Mediterranean Sea are located at Amasra and Antalya regions, respectively. Source regions of SO42- and NO3- are determined by using potential source contribution function (PSCF). Statistical significance of source regions assigned by PSCF were assured using bootstrapping with 3000 iterations. Source regions affecting sulfate and nitrate concentrations at the Mediterranean and Black Sea regions have some similarities and differences. Emissions from source regions in Russia and Balkan countries affect both the Mediterranean and Black Sea basins