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This study provides a comprehensive analysis of changes in mean and extreme temperature indices for Serbia using a high‐resolution daily gridded temperature data set during the period of 1951–2020. The annual and seasonal trends of the indices in the gridded fields were computed and tested for statistical significance using the nonparametric Mann–Kendall test and the Sen's slope estimator. The t‐test was applied to check the stability of means of temperature indices between two standard periods (1961–1990 and 1991–2020). A correlation analysis was used in order to investigate the connections of the large‐scale circulation patterns and the mean and extreme temperature indices. Results showed that a warming trend dominated for the last 70 years, with slightly more intense changes for the mean maximum temperatures (TXM) than for the mean minimum temperatures (TNM). An increase was recorded for indices based on the maximum temperature (TXM, hottest days, warm days, summer days) and minimum temperature (TNM, coldest nights, warm nights, tropical nights). The highest increase was observed for warm nights (7 days⋅decade−1) during the summer season. The negative change in cool days (−1.5 days⋅decade−1) and cool nights (−2 days⋅decade−1) was recorded in almost all seasons, being significant for the both annual and summer values. The correlation between the temperature indices and large‐scale circulation patterns revealed that the East Atlantic (EA) pattern had a highly positive correlation with warm temperature indices (hottest days, warm days, warm nights, summer days, and tropical nights) and a negative correlation with cold indices (coldest nights, cool days, cool nights, frost days, and ice days). The North Atlantic Oscillation, the most important teleconnection pattern during the winter months in Europe, had weaker influence on temperature indices in Serbia than the EA pattern, but stronger than the EA/Western Russia pattern. [ABSTRACT FROM AUTHOR]

It is widely known that the North Atlantic Oscillation (NAO) has an influence on precipitation in Europe. There are other modes of variability such as the East Atlantic (EA) pattern, the East Atlantic/West Russia pattern (EA/WR), the Scandinavia pattern (SCAND), and the Pacific/North American pattern (PNA), which characterize the climate variability in the Northern Hemisphere. In this study, the influence of the EA/WR pattern on precipitation over Europe is examined, with a focus on Serbia. In addition, we explore the combined effects of positive and negative phases of the NAO and EA pattern with the EA/WR pattern, on precipitation over Europe and Serbia. Precipitation data are obtained from the Global Precipitation Climatology Centre (GPCC) and 15 stations from the national observational network in Serbia. Precipitation anomalies have been explored in relation to positive and negative phases of the EA/WR pattern using the monthly GPCC dataset. For the negative (positive) EA/WR phase, positive (negative) precipitation anomalies prevail over the Balkan Peninsula and central Mediterranean in January, February, May, and November, while a negative (positive) one dominates in March, April, September, and during the summer months. There is a strong positive (negative) signal over Portugal in October and over Greece and the Ionian Sea in December, for the positive (negative) EA/WR phase. The precipitation anomalies associated with the negative phase of the EA/WR pattern reflect above (up to 6 mm) average precipitation over Serbia. The positive phase of the EA/WR pattern caused precipitation anomalies below (up to − 8 mm) average precipitation over Serbia. We find that the NAO and EA patterns enhance the influence of the EA/WR pattern on precipitation changes over Serbia. High positive values of precipitation anomalies existed over Serbia for the negative phases of the EA/WR pattern and NAO (up to 12 mm), and EA pattern (up to 10 mm). Negative precipitation anomalies (up to − 12 mm) over Serbia are caused by the positive phase of the EA/WR pattern in combination with the positive phases of the NAO and EA pattern. [ABSTRACT FROM AUTHOR]

Virtual reality (VR) technologies have experienced rapid development in recent years, leading to low‐cost consumer smartphone VR systems (with 3DoF tracking). One issue with the smartphone VR systems, which rely on existing generic displays, is simulator sickness, which arises due to factors that induce sensory conflicts, especially related to visual–vestibular conflict. Display update latency with respect to head position is one of the most widely implicated factors for simulator sickness. However, studies of the effects of latency on simulator sickness have given inconsistent results. Moreover, these studies were done on systems with latencies much higher than current smartphone VR systems. Therefore, it is hard to generalize those results to today's VR systems. To address this, we present in this paper a study on the effect of latency on simulator sickness for latency levels around 20 ms. We present a systematic evaluation of simulator sickness in smartphone VR, testing for a difference between conditions with latencies of 18 and 28 ms, on a task of natural game playing in smartphone VR. We noted differences between individuals in their reported simulator sickness for the two latency conditions but no sample‐wide significant difference. [ABSTRACT FROM AUTHOR]

The Djerdap National Park in Serbia is vulnerable to fires. The variability of a fire in the Djerdap National Park is studied depending on the impact of climatic conditions. The influence was investigated on a yearly, monthly, and daily basis using data recorded at the meteorological station Veliko Gradiste. Data were analyzed for two periods: 1961-1990 and 1991-2017, and for the year of 2011. Special attention is devoted to the conditions for the emergence of the largest forest fire in the Djerdap National Park in September 2011. In this study, the Angstrom index, the Nesterov index, and method of deficit and surplus of precipitation are used to predict the risk of fire. There was an increased danger of fire in the forests in the period of 1991-2017 compared to the period of 1961-1990. Indices showing fire risk are increased for the months of June, July, and August. The September 2011 is characterized by an increase of average monthly air temperature by 3.7 °C and a reduction of the total monthly rainfall of 32.3 mm compared to a long-term average value which favorable influenced to the occurrence of large forest fires. [ABSTRACT FROM AUTHOR]

In order to examine the influence of cultivars and to estimate how mulching and plant covering with agrotextile affects the content of P, Ca, K, Mg and Mn in lettuce leaves this three-year experiment has been established. In the experiment, black and white plastic foil were used for mulching prior to planting, and agrotextile for plant covering after planting. The effect of each of them as well as their combination on the content of nutrients and yield of lettuce leaves was examined. There were six treatments in the experiment: control, black foil, white foil, black foil and agrotextile, white foil and agrotextile, and agrotextile. Mulching had a significant impact on yield, as well as the content of P, Ca, K, Mg and Mn in lettuce leaves in the three-year experiment. The highest yield was registered in the cultivar Nizzi in treatment with black plastic foil, compared to all cultivars and treatments. The largest P content was registered in the cultivar Sunstar (0.71%), while the smallest content was registered in the cultivar Sunny (0.59%). The Ca content ranged from 2.59% (Sunny) to 2.84% (Nizzi). The Mg content ranged from 0.46% in treatment with black foil to 0.70% in treatment with white foil. The content of Mn in lettuce leaves ranged from 60.99 mg kg-1 in the cultivar Zeralda to 81.79 mg kg-1 in the cultivar Devonia. [ABSTRACT FROM AUTHOR]

In this study, the influence of the large-scale circulation patterns on temperature in Europe and Serbia is examined. Among the large-scale circulation patterns in the Northern Hemisphere, less attention has been paid to the impact of the East Atlantic/West Russia pattern (EA/WR). The relationship between the EA/WR pattern and geopotential height at 500 hPa is investigated using reanalysis data from National Centres for Environmental Prediction – National Centre for Atmospheric Research. Temperature anomalies have been explored in relation to strong positive and negative phases of the EA/WR pattern for all months. Analyzing the correlation between the EA/WR index (EA/WRI) and geopotential height at 500 hPa, a centre with negative correlation has been found throughout the year over Russia, north of the Caspian Sea. Positive (negative) temperature anomalies prevailed over Eastern (Western) Europe for the strong negative EA/WR phase (EA/WRI < −1). The temperature anomalies associated with the strong positive phase of the EA/WR pattern (EA/WRI > 1) reflect below-average temperatures over Eastern Europe. In addition, we explored the combined effects of positive and negative phases of the North Atlantic Oscillation (NAO) or East Atlantic (EA) pattern with the EA/WR pattern on temperature variations in Europe and Serbia. We find that the effect of the EA/WR pattern on temperature changes is dependent of the EA phase but not of the NAO phase over Serbia. When the EA/WRI is negative and EA pattern or NAO are in positive phase, the positive temperature anomalies prevailed over most of Europe, including Serbia. The highest values of temperature anomalies exist over Serbia for EA/WRI < −1 and EA index > 1. It is found that this case appears more frequently in the last 20 years, contributing to the warming in Europe and Serbia. [ABSTRACT FROM AUTHOR]

The comparative estimation was carried out with seven tomato hybrids (Lycopersicon esculentum Mill.) during the period 2011 to 2013 in greenhouse at Agricultural Institute of Republic of Srpska, Banja Luka, Bosnia and Herzegovina. The aim of this study is to examine the dry matter content, lycopene in fruits and total yield of Dutch tomato hybrids in the conditions of western Bosnia and Herzegovina. The experiment was set up by a randomized block design in three repetitions. The dry matter content ranged from 5.60% to 8.14%. Hybrid and hybrid x year interaction had significant (p<0.05) influence on lycopene content and tomato yield. The factors that had a decisive influence on the content of dry matter, lycopene content in fruit and tomato yield were year, hybrid and cultivation technology. [ABSTRACT FROM AUTHOR]

Spatial and temporal variability of annual and seasonal (summer and winter) precipitation sums and mean temperatures observed at forty-six stations in Slovenia from 1961 to 2011 were analysed. Principal component analysis (PCA) and a varimax rotation with Kaiser normalization were used to determine the dominant precipitation and temperature patterns in Slovenia. Time series data from the PCA (the principal components, PCs) were used to look for the existence of linear trends and periodicity in the precipitation and temperature data using the Mann–Kendall test and spectral analysis. The relationships between the PCs and circulation patterns, such as the North Atlantic Oscillation (NAO), the East Atlantic (EA) pattern, and the East Atlantic/West Russia (EA/WR) pattern, were also examined. The first four PCs of precipitation (temperature) contributed from 78.7% in summer to 94.5% in winter (98.4% in winter to 98.5% in summer) of the total variance, and their loadings indicated that the most (least) intensive signal was observed over mountainous northwest Slovenia. A statistically significant decrease of PC1 in annual precipitation and increase in mean annual and both seasonal temperatures was found. Significant relationships existed between annual and winter precipitation in Slovenia and the NAO, and temperature and the East Atlantic pattern from 1961 to 2011. Applying the spectral analysis, periods of 2.4 years in summer precipitation and 2.8 years in winter precipitation series, and 2.1 years in annual temperature (significant at the 5% level of significance) were found in Slovenia. [ABSTRACT FROM AUTHOR]

ABSTRACT In this study, wet and dry periods were analysed using the Standardized Precipitation Index ( SPI) on timescales of 1, 3, 6 and 12 months ( SPI1, SPI3, SPI6 and SPI12) at ten stations in Serbia during the period 1949-2011. The onset of severe wetness and drought during the period 1999-2001 was presented. The distributions of the monthly precipitation amounts for each station were modelled by a gamma distribution. The severity and duration of the wet and dry periods were calculated. The generalized Pareto distribution ( GPD) was applied to the SPI values for the timescales of 1 and 12 months during the period 1936-2011 in Belgrade. Furthermore, the severity and duration of the wet and dry periods for timescales of 1 and 12 months were analysed using the extreme value theory. Using the time series of the SPI, it was found that the frequency of droughts in the southern part of Serbia was higher than in the other parts of the country. The obtained results indicated that the GPD could be an appropriate distribution for SPI values less than −1 at the 1- and 12-month timescales, and for the severity of the wet and dry periods at the 1-month timescale. [ABSTRACT FROM AUTHOR]

ABSTRACT In this work, the trends of six climate indices based on the daily maximum and minimum temperatures during the period 1949-2009 at 15 stations distributed across Serbia were analysed. The results showed seasonal changes in the minimum and maximum temperature extremes. An analysis of the extreme temperature indices suggested that the Serbian climate generally tended to become warmer in the last 61 years. The most significant temperature trends were revealed for the summer season. The influence of large-scale variables on the temperature was examined by means of the empirical orthogonal function and correlation. It was found that the East Atlantic pattern dominated during the winter, spring and summer, while the East Atlantic/West Russia pattern governed during the autumn. In addition, the North Atlantic Oscillation dominated the Serbian extreme temperature variability during the winter. [ABSTRACT FROM AUTHOR]

A statistical analysis of the daily maximum and mean monthly precipitation measured at ten meteorological stations in Serbia during the period 1949-2007 is presented. Although the means of the daily maximum and monthly precipitation varied throughout the year, their ratio was almost uniform, with an average value of 32.6% for Serbia. The precipitation events within each year were ranked and then the trends on the ten wettest days of the year were assessed. Averaged across Serbia, the wettest day of the year produces 41.3 mm of precipitation and accounted for 6.3% of the total annual precipitation. Taken together, 35.5% (232.0 mm) of the total annual precipitation fell during the ten wettest days of the year. Over the course of the twentieth century, the average annual precipitation on the wettest day across Serbia increased by nearly 9%. Also, averaged across Serbia, statistically insignificant increasing trends were found on each of the ten wettest days of the year. Furthermore, four climate indices were analysed. Heavy precipitation indices (i.e., RR20 and R95T) increased in Serbia at the end of the twentieth century and thereafter. [ABSTRACT FROM AUTHOR]

Abstract: In this study, heat waves at three meteorological stations in Serbia were analyzed based on the daily maximum temperature during the summer (June, July and August). The warmest summers as regards heat wave duration and severity occurred within the periods 1951–1952, 1987–1998 (especially 1994) and 2000–2007. The longest heat waves were recorded in 1952, lasting 16 days in Smederevska Palanka and 21 days in Niš, while in 1994 in Belgrade lasting 18 days. The summer of 1994 in Belgrade and Smederevska Palanka, and 2003 in Niš were characterized with the highest number of consecutive tropical days (21 and 29, respectively). The autoregressive-moving-average models were applied to generate long series of the daily maximum temperature, from which the relative frequencies of heat waves were estimated. The relationships between the longest heat waves, and the circulation conditions were analyzed using the subjective Hess–Brezowsky catalogue of weather types. [Copyright &y& Elsevier]

In this study, extremely warm and cold temperature events were examined based on daily maximum (Tx) and minimum (Tn) temperatures observed at 11 stations in Serbia during the period 1949–2018. Summer days (SU), warm days (Tx90), and heat waves (HWs) were calculated based on daily maximum temperatures, while frost days (FD) and cold nights (Tn10) were derived from daily minimum temperatures. Absolute maximum and minimum temperatures in Serbia rose but were statistically significant only for Tx in winter. Positive trends of summer and warm days, and negative trends of frost days and cold nights were found. A high number of warm events (SU, Tx90, and HWs) were recorded over the last 20 years. Multiple linear regression (MLR) models were applied to find the relationship between extreme temperature events and atmospheric circulation. Typical atmospheric circulation patterns, previously determined for Serbia, were used as predictor variables. It was found that MLR models gave the best results for Tx90, FD, and Tn10 in winter. [ABSTRACT FROM AUTHOR]

In this work we analyse yearly standardized precipitation evapotranspiration index for accumulation timescale of 6 months (SPEI‐6) for August which has been identified as a strong proxy for corn production in Serbia. By applying recently proposed method generalized weighted permutation entropy (GWPE), which provides the information about predictability of large/small fluctuations in nonstationary time series, on SPEI index calculated from high‐resolution gridded dataset for the period 1951–2022, we found that the small fluctuation sequences of consecutive 4‐year SPEI values are the most predictable (indicated by lowest entropy values). The order of large fluctuation sequences is less predictable, while the order of sequences considering all magnitudes of fluctuations are the least predictable (indicated by highest entropy values). We also analysed 4‐month SPEI‐6 sequences for May, June, July and August (during the growing season of corn) along the years under study and found that they display lower GWPE values and thus are more predictable than yearly SPEI‐6 August sequences (small fluctuations displaying lower entropy values than large fluctuations). Regarding spatial distributions, in both cases SPEI‐6 sequences show similar pattern for large fluctuations: higher predictability (lower entropy values) in northern and eastern part of Serbia and lower predictability (higher entropy values) in southern and western part. For small fluctuations spatial distribution of GWPE values indicates that yearly SPEI‐6 August series are more predictable in the western part of the country while May to August monthly SPEI‐6 sequences are more predictable in the eastern part. [ABSTRACT FROM AUTHOR]

Rainfall seasonality in Serbia is examined trough the analysis of several indices: seasonality index (SI), individual seasonality index ( SI i) , and replicability index (RI). Based on data from 14 synoptic stations that are well distributed over Serbian territory, spatial distribution of general seasonality index SI ¯ , mean individual seasonality index SI ind ¯ , and RI are analyzed in two subperiods (1961–1990 and 1991–2020). The modified Mann–Kendall test (MMK) and Sen's slope methods are used to investigate the possible trends and its magnitudes in time series of SI i . The values of SI ¯ show that precipitation regime in Serbia is very equitable or equitable with definite wetter season. For the entire Serbian territory, the values of RI are low, indicating that the month of maximum rainfall occurs over large spread of months along the studied periods. The existence of significant negative correlation between RI and longitude is found. Results show a highest influence of the North Atlantic Oscillation and East Atlantic/West Russia pattern on rainfall seasonality in Serbia. [ABSTRACT FROM AUTHOR]

This paper focuses on the possible impact of the thermal soil regime on the occurrence of forest fires in the Zaječar administrative district in Eastern Serbia. The study uses data on soil temperature from the Republic Hydrometeorological Service of the Republic of Serbia and the ERA5-Land gridded reanalysis dataset for monthly temperature and volumetric soil water of the soil level 1 (0-7 cm), and soil level 2 (7-28 cm) with horizontal resolution of 0.1°C (approximately 12 km × 12 km) during the period of 2009-2021. Differences in soil temperature at depths of 2 cm, 5 cm, 10 cm, and 20 cm at the meteorological station in Zaječar for the periods 1961-1990 and 2009-2021 are observed. By analyzing the data on the registered number of forest fires for the period 2009-2021, pronounced oscillations in the dynamics of forest fires can be observed. The minimum number of forest fires (0) is registered in 2014, when the maximum of soil moisture in the soil levels 1 and 2 is observed. A high number of forest fires corresponds to high soil temperatures in 2012 and 2017. Soils drier and hotter than the average are registered in 47.0% of all months with the fire occurrences. About 50% of fires occurred in dry and hot soils during 2012 and 2017. This percentage was zero in 2014, when there were no fires. [ABSTRACT FROM AUTHOR]

We investigate multifractal properties of daily means of air temperature over the territory of Serbia, by using Multifractal detrended fluctuation analysis. Temperature anomalies in two periods 1961–1990 and 1991–2020 are calculated from the E-OBSv26.0e gridded dataset with 0.10° (~12 km) resolution, totaling 1278 daily temperature series for each period. The MFDFA parameters: position of the maximum of the spectrum α0, width of the spectrum W and asymmetry r, obtained from the total of 2556 MFDFA runs are interpolated to yield their spatial distribution across Serbia in the two periods. We found several patterns in both the spatial distribution, and changes from first to second period. All series showed multifractal properties with overall persistent long-term correlations (α0 > 0.5) and the dominance of small fluctuations (r > 0). The persistence is weaker (smaller α0 values) and multifractality is stronger (larger width W) in southern mountainous regions. In the second period the values of α0 increased indicating stronger persistence of temperature dynamics, while multifractality became stronger (larger W) in northern region and weaker (smaller W) in southern region. In both periods the contribution to multifractality was dominated by small fluctuations (r > 0) that become stronger in the second period, indicated by the increase of the values of r over most of the country's area. These changes in the values of multifractal parameters indicate the increase of complexity of temperature dynamics in the second 30 years period which could be related to climate change. [ABSTRACT FROM AUTHOR]

The aim of this research was to determine the effect of the application of different types of nitrogen fertilizer in five different varieties of lettuce on yield. The experiment was performed in the open field, in the spring cycle of growing during 2018 and 2019. The size of the base plot was 3 m², and the trial was set up in a random block system. The trial covered the application of various forms of nitrogen fertilizers: ammonium sulphate, ammonium nitrate and urea. The applied nitrogen dose is 100 kg/ha (May 10th 2018 and May 8th 2019). Samples for the analysis of vitamin C and nitrate content, as well as yield determination, were carried out at the stage of the technological maturity of lettuce (60-62 days after seedling). The average weight of lettuce, depending on the variety, varied in the range of 211.3 g to 258.7 g. The use of ammonium nitrate resulted in the highest average weight of lettuce head (246.7 g), followed by the use of urea (238.9 g) and the lowest by the use of ammonium sulphate (221.0 g). The nutritional value of lettuce (vitamin C content) shows that depending on the applied form of nitrogen in the fertilizer, the highest content of vitamin C was determined by urea (10.86 mg/100 g), then ammonium sulphate (9.61 mg/100 g), and the lowest by ammonium nitrate (7.38 mg/100 g). The lower content of vitamin C was found in varieties of lettuce with red leaves compared to varieties with green leaves. The accumulation of nitrate in lettuce leaves directly depends on the variety and the applied fertilizer. The highest nitrate content was with ammonium nitrate (2355.6 mg/kg). The accumulation of nitrate in lettuce varieties with red leaves was higher compared to varieties with green leaves. [ABSTRACT FROM AUTHOR]

The purpose of this study is to analyze the spatiotemporal variations in drought in Serbia over recent decades using the standardized precipitation evapotranspiration index (SPEI). The analysis is performed for time series of 1-, 3-, 6-, and 12-month SPEI indices (SPEI-01, SPEI-03, SPEI-06 and SPEI-12, respectively) calculated using the E -OBS gridded dataset with a horizontal resolution of 0.1° for the period of 1950–2022. In general, it was found that negative SPEI trends prevailed in Serbia for all months and all analyzed SPEI timescales, indicating a more frequent appearance of droughts in recent decades. Moreover, for a large majority of month-timescale combinations, the area with a negative trend was larger than the area with a positive trend. For several reasons, we focused on the SPEI for August. First, the SPEI for this month shows one of the most pronounced negative trends, which is rather consistent over different timescales and consistent in terms of the area over which the trend was found to be significant. Statistically significant negative trends of SPEI-03, −06 and − 12 for August were found over 11, 17 and 38% of the country area, respectively. To better understand the trends and changes in the SPEI for August, focusing on extreme and severe drought events, an innovative trend analysis (ITA) was applied. It was found that the occurrence of both extreme and severe SPEI drought categories has doubled over the last thirty years in comparison with the previous thirty-year period. Additionally, more frequent transitions from neutral and wet categories to dry categories were observed through an application of the Markov chain. Second, the special focus on SPEI-03, −06 and − 12 for August was motivated by the fact that we found a significant correlation between these index values and the annual maize production in Serbia, indicating that the SPEI for August can be useful for the assessment of drought impact on agriculture. To better understand interannual variability and long-term trends, this paper also explores the relations between the SPEI over Serbia and large-scale circulation patterns, together with general global and continental warming trends. Our findings indicate that drought changes over recent decades may be driven by the interplay of long-term warming and large-scale circulation patterns. In the context of climate change, especially climate projections, Serbia is situated in a region for which climate projections of mean precipitation change demonstrate weak signals and often with conflicting signs of change within multimodel ensembles. From this point of view, our results can be seen as a contribution to a better understanding of changes in extremes, in our case droughts, that can be hidden by inconclusive changes in the mean values. Finally, due to the similar situation in terms of precipitation and drought trends and changes, our results may be relevant for a wider region, and not only for Serbia. • For Serbia negative trends in SPEI index, for different months and timescales, are dominant. • Occurrence of extreme drought categories has doubled over the last decades. • Transitions from neutral and wet categories to dry categories are more frequent. • These changes are driven by long-term warming and large-scale circulation patterns. [ABSTRACT FROM AUTHOR]

A sampling site at Herceg-Novi (Montenegro) is included in the network for the monitoring of airborne pollutants along the Mediterranean coast. The 24-h concentrations of total suspended particles (TSP) were measured by a standardized gravimetric method in a 1-in-6 day schedule program. The available data set from the period 1995–2000 was chosen for statistical analysis. The 3-parameter Weibull probability model successfully described the distributions of TSP concentrations as the total population and the part of them transported from the continental side. However, in the concentration set from the southern segment, outliers were found indicating the appearance of the highest concentrations from the open Adriatic Sea. The collected particles mostly constituted of PM10 and the ratio PM10/TSP reached value of 0.9. An analysis of the filter samples by scanning electron microscopy (SEM) confirmed the presence of marine aerosol, crustal and amorphous material. The Fe content of >2% in the TSP samples was accepted for the identification of genuine Saharan dust transport. The frequency of these events of 7% a year contributed to an increase of the annual TSP concentrations of 10%–15%. The amorphous material was found in the sample of 31 May/1 June 1999 after the bombing of Cape Arza on the Luštica Peninsula, which is situated 5 km away from the sampling site. The attack occurred on 30 May and depleted uranium ammunition was used. The 238U radioactivity was at the background level, but the pulverous material found in that sample most likely originated from dust and soil transported from Cape Arza to Herceg-Novi on 31 May as the backward trajectory analysis by the Eta model showed. Resuspension was the dominant process affecting the TSP concentration, but this episode did not reflect significantly on the annual TSP levels, as is the case with the Saharan dust storms. The methodology applied in this work allowed a fugitive source of PM from destroyed objects and bombed terrain to be discovered. [Copyright &y& Elsevier]

A simple two-dimensional linearized model of the atmosphere is used to investigate behavior of the geostrophic adjustment process on five selected horizontal hexagonal grids. This study shows that hexagonal lattices have some advantages over commonly used square grids. Having better isotropy, they provide more accurate dispersion of gravity waves than square grids do, and therefore they can be more appropriate for simulation of smaller-scale divergent processes. The gravity–inertia wave frequencies of most of the considered grids are also closer to the true solution than those on square grids. However, some hexagonal grids are not completely free of numerical inconsistencies. For example, one of the selected grids generates nonsymmetric roots of the gravity–inertia solution that may lead to the unwanted simulation of the atmospheric process. The analysis indicates which hexagonal distributions can be an appropriate choice for use in atmospheric and ocean models. [ABSTRACT FROM AUTHOR]

Abstract Magnetic properties of soils formed in and on loess substrate and their relation to climate are of general interest in paleoclimate and pedological research. The loess-paleosol sequences (LPS) in the Vojvodina region (Serbia) have been the subject of intensive study. On the Bačka loess plateau (BLP), covering approximately 2500 km2, six different soil types are observed. While the stratigraphy of the LPS has been investigated the relation between climatic factors and magnetic properties of surface soil have not yet been examined. In this study we analyze 50 samples of chernozem soils, which have been dominated by climatic factors during their formation. Previous studies have confirmed that the formation of magnetic properties in soils is related to climate, and especially rainfall, because of the response of hematite and goethite to different, climatically-driven regimes. The sensitivity of certain iron-bearing minerals to climate has also been documented in the literature. Climatic variables for the BLP were derived from six-decade national meteorological datasets. Low frequency magnetic susceptibility (χ) and frequency dependent magnetic susceptibility (χ fd) were determined for each site and compared to the mean annual precipitation (MAP), mean annual temperature (MAT) and the De Martonne aridity index (I DM). The meteorological variables were interpolated to sampling points by Kriging method in ArcMap 10.1. Our results suggest that values of χ and χ fd both decrease from south to north and so does the precipitation. Thus, our work provides new evidence for the relationship between precipitation, temperature, aridity and magnetic properties of modern top soils. The obtained and analyzed data may help in the future to improve transfer functions of the relationship between magnetic susceptibility and climatic data. [ABSTRACT FROM AUTHOR]

For investigating aridity in Vojvodina, two parameters were used: the De Martonne aridity index and the Pinna combinative index. These indices were chosen as the most suitable for the analysis of climate in Vojvodina (a region in northern part of Serbia). Also, these indices were calculated from data obtained from 10 meteorological stations for the period from 1949 to 2006. The spatial distribution of the annual and seasonal De Martonne and the Pinna combinative indices as well as the mean monthly values of the De Martonne index and aridity trends of these indices are presented. There were two, four, and five types of climate on a yearly, seasonal, and monthly basis in Vojvodina, according to the De Martonne climate classification which consists of a total of seven types. In addition, semi-humid and humid climate types were represented in the region, on a yearly basis. The winter season was dominated by wetter types of climate, while the summer season was characterized by drier ones. During the spring and autumn seasons, there were types of climate which range between both aforementioned types. Two out of three climate types, which can be identified using the Pinna combinative index, were registered in Vojvodina region. The most dominant climate type was the semidry Mediterranean with formal Mediterranean vegetation, while the humid type was only identified in one small part of southwestern Vojvodina. The calculated values of both aridity indices showed that there were no annual trends. Therefore, it can be considered that there were no recent aridity changes during the observed period. For paleoclimate, the general story is more complex. The lack of aridity trends in the recent period from 1949 to 2006 supports the fact that Vojvodina has very well preserved loess-palaeosol sequences from the Middle and Late Pleistocene, which indicates that crucial point for their preservation was caused by the weak aridity variability in the region. [ABSTRACT FROM AUTHOR]