Lazar Lazic | University of Belgrade (original) (raw)
Papers by Lazar Lazic
WORLD SCIENTIFIC eBooks, 1996
Meteorology and Atmospheric Physics, Sep 1, 1998
Summary This study addresses simulation of the local bora wind and its properties as reflected on... more Summary This study addresses simulation of the local bora wind and its properties as reflected on typical trajectories. Trajectory calculations are implemented in the Eta Model. The Eta Model has a vertical coordinate which permits a step-like representation of mountains and quasi-horizontal coordinate surfaces, the so-called eta coordinate. A realistic real data simulation of a bora wind case in achieved using the model with a 28 km horizontal resolution and 16 layers in the vertical. Numerical experiments with different mountain heights and shapes in the bora wind region are performed. These are motivated by observational indications and theoretically based expectations that a certain intermediate mountain elevation is required for generation of downslope windstorms with bora wind properties. Three-dimensional trajectories over various mountains mimicing real mountains but differing primarily in elevation are calculated and analysed. The maximum bora wind speed is predicted as expected through three-dimensional channels in the step mountain representations. The results illustrate and are in agreement with the observational evidence that mountain barriers of the elevation of about 1000 m are a necessary requirement for the occurrence of the bora-type downslope windstorms.
Nucleation and Atmospheric Aerosols, 2007
ABSTRACT A pilot study was performed to assess the concentration level of ambient suspended parti... more ABSTRACT A pilot study was performed to assess the concentration level of ambient suspended particulate matter PM10 and PM2.5 in the Belgrade urban area. This study has shown theoretical and experimental evidence of pollutants for characteristic measurements when maximum PM concentrations occurred. For this study, 60-h air-back trajectories are calculated. When the air masses were coming from the SW direction, the contribution from the complex of coal-fired power plants was evident.
Meteorology and Atmospheric Physics, Aug 7, 2003
The Balkan Peninsula is situated in the impact zone of Saharan dust storms. The case of Saharan d... more The Balkan Peninsula is situated in the impact zone of Saharan dust storms. The case of Saharan dust transport to Belgrade in the period of 14-17 April 1994 is analyzed using the Eta model for synoptic and meso scale processes. Air back trajectories are calculated at six model levels from 434 up to 5129 m with horizontal grid resolutions of 1 Â 1 and 10 0 Â 10 0. Following cyclonic circulation the dust was picked up from North Africa, and transported over Mediterranean. Simultaneously, according to the analysis of the three lowest trajectories, transport of trace metals from Macedonia and southern Serbia by the Koshava wind might be dominant in the observed episode. Turbulent flow enhanced the coagulation process of initially clean dust particles with particles containing Pb and Cd. The coagulation and scavenging processes below and in clouds increased deposition rates of Pb and Cd in Belgrade in the course of wet removal, and consequently trough resuspension processes. Dry deposition samples contained characteristic particles up to 30 mm in diameter with Fe content of 11 to 15 atomic% and significant ratio Si=Fe of 3 to 5, determined for selected single particles by the SEM=EDX method. Following dry and wet deposition of Cd and Pb, a residual effect of dustfall is noticed throughout the vegetational period.
Science of The Total Environment, Feb 1, 2019
Current research suggests that, apart from photochemical reactions, toluene, ethylbenzene and xyl... more Current research suggests that, apart from photochemical reactions, toluene, ethylbenzene and xylene (TEX) removal from ambient air might be affected by atmospheric precipitation, depending on the concentrations and water solubility of the compounds, Henry's law, physico-chemical properties of the water, as well as the frequency and intensity of precipitation events. Nevertheless, existing knowledge of the role that wet deposition plays in biogeochemical cycles of volatile species remains insufficient, and this topic requires more scientific effort to be explored and understood. In this study, we employed the eXtreme Gradient Boosting tree ensemble for revealing TEX transfer from ambient air to rainwater, and applied a novel SHapley Additive exPlanations feature attribution framework to examine the relevance of the monitored parameters and identify key factors that govern wet deposition of TEX. According to the results, main impacts, including ambient air TEX concentrations, and rainwater and air temperatures, and occasional, but less important impacts, including wind speed, air pressure, turbidity, and total organic carbon, NO 3 − , Cl − and K + rainwater concentration, shaped TEX partition between gaseous and aqueous phases during rain events.
Energy, Aug 1, 2014
The goal of this article is to apply the regional atmospheric numerical weather prediction e the ... more The goal of this article is to apply the regional atmospheric numerical weather prediction e the Eta model, improved by the new proposed MOS (Model Output Statistics) method and to describe its performance in validation of the wind forecasts for wind power plants. The Eta model has been compared against the wind from tower observations at a number of levels (10, 38, 54, 75, 96 and 145 m), with a total number of 15984 pairs of forecast and observed winds. The new MOS method is applied in two different ways: 1) with one predictor e wind from the Eta model forecast; 2) with two predictors e wind from the Eta model forecast and wind from the recent observations, originally proposed in this study. The average overall results are: Mean Error of 0.27 m/s; Mean Absolute Error of 0.93 m/s; Root Mean Square Error of 1.19 m/s and Coefficient of Determination of 0.79. The results indicate that the Eta model with the proposed MOS method is quite usable as a meteorological driver for wind energy modelling and prediction across any geographical region.
Atmospheric Environment, Sep 1, 2016
Abstract To investigate the air pollutant distribution within the ambient of urban street canyon,... more Abstract To investigate the air pollutant distribution within the ambient of urban street canyon, Operational Street Pollution Model (OSPM) was used to predict hourly content of NO X , NO, NO 2 , O 3 , CO, BNZ and PM10. The study was performed in five street canyons in Belgrade (Serbia) during 10-week summer period. The model receptors were located on each side of street canyons at 4 m, 8 m and 16 m height. To monitor airborne trace element content, the moss bag biomonitors were simultaneously exposed with the model receptors at two heights–4 m and 16 m. The results of both methods, modelling and biomonitoring, showed significantly decreasing trend of the air pollutants with height. The results indirectly demonstrate that biomonitoring, i.e., moss bag technique could be a valuable tool to verify model performance. In addition, spectral analysis was applied to investigate weekly variation of the daily background and modelled data set. Typical periodicities and weekend effect, caused by anthropogenic influences, have been identified.
Renewable Energy, Jun 1, 2010
This article appeared in a journal published by Elsevier. The attached copy is furnished to the a... more This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research and education use, including for instruction at the authors institution and sharing with colleagues. Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited. In most cases authors are permitted to post their version of the article (e.g. in Word or Tex form) to their personal website or institutional repository. Authors requiring further information regarding Elsevier's archiving and manuscript policies are encouraged to visit: http://www.elsevier.com/copyright
Atmospheric Research, Nov 1, 2018
In this study, the influence of the large-scale circulation patterns on temperature in Europe and... more 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.
WIT Transactions on Ecology and the Environment, May 22, 1999
Journal of Geophysical Research: Atmospheres, 2022
Dust aerosols are abundant in the atmosphere and are very efficient ice nucleating particles at t... more Dust aerosols are abundant in the atmosphere and are very efficient ice nucleating particles at temperatures below −15°C. Depending on temperature, dust particles containing certain minerals (i.e., feldspar and quartz) are the most active as ice nuclei. A mineralogy‐sensitive immersion freezing parameterization for ice nucleating particle concentration (INPC) is implemented in Dust Regional Atmospheric Model (DREAM) for the first time. Additionally, four mineralogy‐indifferent parameterizations are implemented, two for immersion freezing and two for deposition nucleation. Dust concentration and its feldspar and quartz fractions are forecasted by DREAM for a dust episode in the Mediterranean in April 2016. DREAM results are compared with vertical profiles of cloud‐relevant dust concentrations and INPC from ground‐based lidar measurements in Potenza, Italy and Nicosia, Cyprus. INPC predictions are also compared with vertical profiles of ice crystal number concentration (ICNC) from sat...
Meteorology and Atmospheric Physics, Mar 1, 1998
... Department of Meteorology, University of Belgrade, Yugoslavia Improved Bora Wind Simulation U... more ... Department of Meteorology, University of Belgrade, Yugoslavia Improved Bora Wind Simulation Using a Nested Eta Model ... Summary This paper reports on improvements obtained in simulations of bora wind using a nesting technique in a primitive equations model. ...
Journal of Voice, 2011
Objectives. The aim of the investigation was to obtain acoustic correlates of the vocal quality o... more Objectives. The aim of the investigation was to obtain acoustic correlates of the vocal quality of patients with vocal polyps, before and after the endolaryngeal phonomicrosurgery (EPM). Methods. Acoustic voice tests were carried out on 46 female patients with vocal fold polyp, before the EPM intervention and 3 weeks after its completion. Acoustic voice parameters were compared with the control group without voice pathology. The results of the investigation were analyzed acoustically. Results. The results showed that jitter (%), shimmer (%), fundamental frequency variation (vF 0 ), voice turbulence index (VTI), pitch perturbation quotient (PPQ), amplitude perturbation quotient (APQ), and NHR values significantly differentiate the patients with vocal fold polyps from a control group without any pathological changes in the larynx. All of the analyzed parameters improved significantly (P < 0.05) after the phonomicrosurgical intervention and tended to reach normal values. Conclusions. The acoustic voice analysis may be used for presurgical and postsurgical voice-status evaluation.
Sustainability
The aim of this work is to assess damage to the City of Belgrade caused by the unfavorable weathe... more The aim of this work is to assess damage to the City of Belgrade caused by the unfavorable weather condition of hail due to the absence of anti-hail defense of the city, and to argumentatively point out the necessity of introducing new technical-technological systems for preventing the effects of adverse weather conditions. The results are based on the direct correlation-analyses of two real unfavorable weather events and the estimated financial damage caused by these events. The overall calculation also takes into account financial investments (new financial model) necessary to establish two essentially different systems for anti-hail protection. The damage caused by the hail on the territory of the City of Belgrade and the financial investment in anti-hail protection to reduce it are empirically established for the first time. It is shown how the damage could be transformed to profit, as the financial investment in anti-hail protection is lower than the damage that hail can cause.
AIP Conference Proceedings, 2007
Meteorol Atmos Phys, 1986
Meteorology and Atmospheric Physics, Feb 28, 1998
Environmental Monitoring and Assessment, 2008
WORLD SCIENTIFIC eBooks, 1996
Meteorology and Atmospheric Physics, Sep 1, 1998
Summary This study addresses simulation of the local bora wind and its properties as reflected on... more Summary This study addresses simulation of the local bora wind and its properties as reflected on typical trajectories. Trajectory calculations are implemented in the Eta Model. The Eta Model has a vertical coordinate which permits a step-like representation of mountains and quasi-horizontal coordinate surfaces, the so-called eta coordinate. A realistic real data simulation of a bora wind case in achieved using the model with a 28 km horizontal resolution and 16 layers in the vertical. Numerical experiments with different mountain heights and shapes in the bora wind region are performed. These are motivated by observational indications and theoretically based expectations that a certain intermediate mountain elevation is required for generation of downslope windstorms with bora wind properties. Three-dimensional trajectories over various mountains mimicing real mountains but differing primarily in elevation are calculated and analysed. The maximum bora wind speed is predicted as expected through three-dimensional channels in the step mountain representations. The results illustrate and are in agreement with the observational evidence that mountain barriers of the elevation of about 1000 m are a necessary requirement for the occurrence of the bora-type downslope windstorms.
Nucleation and Atmospheric Aerosols, 2007
ABSTRACT A pilot study was performed to assess the concentration level of ambient suspended parti... more ABSTRACT A pilot study was performed to assess the concentration level of ambient suspended particulate matter PM10 and PM2.5 in the Belgrade urban area. This study has shown theoretical and experimental evidence of pollutants for characteristic measurements when maximum PM concentrations occurred. For this study, 60-h air-back trajectories are calculated. When the air masses were coming from the SW direction, the contribution from the complex of coal-fired power plants was evident.
Meteorology and Atmospheric Physics, Aug 7, 2003
The Balkan Peninsula is situated in the impact zone of Saharan dust storms. The case of Saharan d... more The Balkan Peninsula is situated in the impact zone of Saharan dust storms. The case of Saharan dust transport to Belgrade in the period of 14-17 April 1994 is analyzed using the Eta model for synoptic and meso scale processes. Air back trajectories are calculated at six model levels from 434 up to 5129 m with horizontal grid resolutions of 1 Â 1 and 10 0 Â 10 0. Following cyclonic circulation the dust was picked up from North Africa, and transported over Mediterranean. Simultaneously, according to the analysis of the three lowest trajectories, transport of trace metals from Macedonia and southern Serbia by the Koshava wind might be dominant in the observed episode. Turbulent flow enhanced the coagulation process of initially clean dust particles with particles containing Pb and Cd. The coagulation and scavenging processes below and in clouds increased deposition rates of Pb and Cd in Belgrade in the course of wet removal, and consequently trough resuspension processes. Dry deposition samples contained characteristic particles up to 30 mm in diameter with Fe content of 11 to 15 atomic% and significant ratio Si=Fe of 3 to 5, determined for selected single particles by the SEM=EDX method. Following dry and wet deposition of Cd and Pb, a residual effect of dustfall is noticed throughout the vegetational period.
Science of The Total Environment, Feb 1, 2019
Current research suggests that, apart from photochemical reactions, toluene, ethylbenzene and xyl... more Current research suggests that, apart from photochemical reactions, toluene, ethylbenzene and xylene (TEX) removal from ambient air might be affected by atmospheric precipitation, depending on the concentrations and water solubility of the compounds, Henry's law, physico-chemical properties of the water, as well as the frequency and intensity of precipitation events. Nevertheless, existing knowledge of the role that wet deposition plays in biogeochemical cycles of volatile species remains insufficient, and this topic requires more scientific effort to be explored and understood. In this study, we employed the eXtreme Gradient Boosting tree ensemble for revealing TEX transfer from ambient air to rainwater, and applied a novel SHapley Additive exPlanations feature attribution framework to examine the relevance of the monitored parameters and identify key factors that govern wet deposition of TEX. According to the results, main impacts, including ambient air TEX concentrations, and rainwater and air temperatures, and occasional, but less important impacts, including wind speed, air pressure, turbidity, and total organic carbon, NO 3 − , Cl − and K + rainwater concentration, shaped TEX partition between gaseous and aqueous phases during rain events.
Energy, Aug 1, 2014
The goal of this article is to apply the regional atmospheric numerical weather prediction e the ... more The goal of this article is to apply the regional atmospheric numerical weather prediction e the Eta model, improved by the new proposed MOS (Model Output Statistics) method and to describe its performance in validation of the wind forecasts for wind power plants. The Eta model has been compared against the wind from tower observations at a number of levels (10, 38, 54, 75, 96 and 145 m), with a total number of 15984 pairs of forecast and observed winds. The new MOS method is applied in two different ways: 1) with one predictor e wind from the Eta model forecast; 2) with two predictors e wind from the Eta model forecast and wind from the recent observations, originally proposed in this study. The average overall results are: Mean Error of 0.27 m/s; Mean Absolute Error of 0.93 m/s; Root Mean Square Error of 1.19 m/s and Coefficient of Determination of 0.79. The results indicate that the Eta model with the proposed MOS method is quite usable as a meteorological driver for wind energy modelling and prediction across any geographical region.
Atmospheric Environment, Sep 1, 2016
Abstract To investigate the air pollutant distribution within the ambient of urban street canyon,... more Abstract To investigate the air pollutant distribution within the ambient of urban street canyon, Operational Street Pollution Model (OSPM) was used to predict hourly content of NO X , NO, NO 2 , O 3 , CO, BNZ and PM10. The study was performed in five street canyons in Belgrade (Serbia) during 10-week summer period. The model receptors were located on each side of street canyons at 4 m, 8 m and 16 m height. To monitor airborne trace element content, the moss bag biomonitors were simultaneously exposed with the model receptors at two heights–4 m and 16 m. The results of both methods, modelling and biomonitoring, showed significantly decreasing trend of the air pollutants with height. The results indirectly demonstrate that biomonitoring, i.e., moss bag technique could be a valuable tool to verify model performance. In addition, spectral analysis was applied to investigate weekly variation of the daily background and modelled data set. Typical periodicities and weekend effect, caused by anthropogenic influences, have been identified.
Renewable Energy, Jun 1, 2010
This article appeared in a journal published by Elsevier. The attached copy is furnished to the a... more This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research and education use, including for instruction at the authors institution and sharing with colleagues. Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited. In most cases authors are permitted to post their version of the article (e.g. in Word or Tex form) to their personal website or institutional repository. Authors requiring further information regarding Elsevier's archiving and manuscript policies are encouraged to visit: http://www.elsevier.com/copyright
Atmospheric Research, Nov 1, 2018
In this study, the influence of the large-scale circulation patterns on temperature in Europe and... more 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.
WIT Transactions on Ecology and the Environment, May 22, 1999
Journal of Geophysical Research: Atmospheres, 2022
Dust aerosols are abundant in the atmosphere and are very efficient ice nucleating particles at t... more Dust aerosols are abundant in the atmosphere and are very efficient ice nucleating particles at temperatures below −15°C. Depending on temperature, dust particles containing certain minerals (i.e., feldspar and quartz) are the most active as ice nuclei. A mineralogy‐sensitive immersion freezing parameterization for ice nucleating particle concentration (INPC) is implemented in Dust Regional Atmospheric Model (DREAM) for the first time. Additionally, four mineralogy‐indifferent parameterizations are implemented, two for immersion freezing and two for deposition nucleation. Dust concentration and its feldspar and quartz fractions are forecasted by DREAM for a dust episode in the Mediterranean in April 2016. DREAM results are compared with vertical profiles of cloud‐relevant dust concentrations and INPC from ground‐based lidar measurements in Potenza, Italy and Nicosia, Cyprus. INPC predictions are also compared with vertical profiles of ice crystal number concentration (ICNC) from sat...
Meteorology and Atmospheric Physics, Mar 1, 1998
... Department of Meteorology, University of Belgrade, Yugoslavia Improved Bora Wind Simulation U... more ... Department of Meteorology, University of Belgrade, Yugoslavia Improved Bora Wind Simulation Using a Nested Eta Model ... Summary This paper reports on improvements obtained in simulations of bora wind using a nesting technique in a primitive equations model. ...
Journal of Voice, 2011
Objectives. The aim of the investigation was to obtain acoustic correlates of the vocal quality o... more Objectives. The aim of the investigation was to obtain acoustic correlates of the vocal quality of patients with vocal polyps, before and after the endolaryngeal phonomicrosurgery (EPM). Methods. Acoustic voice tests were carried out on 46 female patients with vocal fold polyp, before the EPM intervention and 3 weeks after its completion. Acoustic voice parameters were compared with the control group without voice pathology. The results of the investigation were analyzed acoustically. Results. The results showed that jitter (%), shimmer (%), fundamental frequency variation (vF 0 ), voice turbulence index (VTI), pitch perturbation quotient (PPQ), amplitude perturbation quotient (APQ), and NHR values significantly differentiate the patients with vocal fold polyps from a control group without any pathological changes in the larynx. All of the analyzed parameters improved significantly (P < 0.05) after the phonomicrosurgical intervention and tended to reach normal values. Conclusions. The acoustic voice analysis may be used for presurgical and postsurgical voice-status evaluation.
Sustainability
The aim of this work is to assess damage to the City of Belgrade caused by the unfavorable weathe... more The aim of this work is to assess damage to the City of Belgrade caused by the unfavorable weather condition of hail due to the absence of anti-hail defense of the city, and to argumentatively point out the necessity of introducing new technical-technological systems for preventing the effects of adverse weather conditions. The results are based on the direct correlation-analyses of two real unfavorable weather events and the estimated financial damage caused by these events. The overall calculation also takes into account financial investments (new financial model) necessary to establish two essentially different systems for anti-hail protection. The damage caused by the hail on the territory of the City of Belgrade and the financial investment in anti-hail protection to reduce it are empirically established for the first time. It is shown how the damage could be transformed to profit, as the financial investment in anti-hail protection is lower than the damage that hail can cause.
AIP Conference Proceedings, 2007
Meteorol Atmos Phys, 1986
Meteorology and Atmospheric Physics, Feb 28, 1998
Environmental Monitoring and Assessment, 2008