Atmospheric deposition processes are of primary importance for human health, forests, agricultura... more Atmospheric deposition processes are of primary importance for human health, forests, agricultural lands, aquatic bodies, and ecosystems. South-East Europe is still characterized by numerous hot spots of elevated sulfur deposition, despite the reduction in European emission sources. The purpose of this study is to discuss the results from two chemical transport models and observations for wet and dry depositions of sulfur (S), reduced nitrogen (RDN) and oxidized nitrogen (OXN) in Bulgaria in 2016–2017. The spatial distribution and the domain main deposition values by EMEP MSC-W (model of the MSC-W Centre of the Co-operative Programme for Monitoring and Evaluation of the Long-range Transmissions of Air Pollutants in Europe) and BgCWFS (Bulgarian Chemical Weather Forecast System) demonstrated S wet depositions to be higher than N depositions, and identified a rural area in south-east Bulgaria as a possible hot-spot. The chemical analysis of deposition samples at three sites showed a p...
The main objective of this study is to evaluate the performance of some well-known and widely use... more The main objective of this study is to evaluate the performance of some well-known and widely used operational air quality modelling systems (EMEP-MSC-W, and the models at the Copernicus Atmosphere Monitoring Service (CAMS)) for simulations of particulate matter in Bulgaria. The analysis is focussed on a summer month (August 2017) and includes comparison of model to observations from 24 regular air quality background stations, as well as model inter-comparison. Along with statistical indicators various graphs are used – box plots, kernel density estimations,and scatter plots. The spatial distribution is discussed upon maps of monthly mean concentrations and comparison of domain averaged model concentrations. The spatial distribution of PM10 is similar only over the Black sea. The highest domain mean surface concentrations are simulated by CAMS global – by about 12 % for PM10 and by about 14 % for PM2.5 higher than the other models.
Black carbon (BC) is one of the particulate matter (PM) components that both affects human health... more Black carbon (BC) is one of the particulate matter (PM) components that both affects human health and contributes to climate change. In this study, we present the preliminary results of the investigation of BC concentrations in PM2.5 for two Bulgarian cites—Sofia and Burgas. The parallel PM2.5 samplings were organized in October 2020 and January 2021. The Multi-Wavelength Absorption Black carbon Instrument (MABI) was used for the evaluation of light-absorbing carbon. In addition, we compared the observed BC and PM2.5 values to modelled ones and analyzed the spatial distribution over the country, using data from advanced operational chemical transport models (CTM)—the European (regional) air quality system established at the Copernicus Atmosphere Monitoring Service (CAMS). Generally, the observed BC and PM2.5 values were higher in January than in October for both cities. In October, the model underestimated the observed BC concentrations (Sofia—2.44 μg.m−3, Burgas—1.63 μg.m−3) by 17%...
As part of the FAIRMODE benchmarking activities (Thunis et al., 2010), performance criteria for a... more As part of the FAIRMODE benchmarking activities (Thunis et al., 2010), performance criteria for air quality modelling in the frame of the EU Air Quality directive (AQD) 2008 are proposed and tested. The suggested approach builds on the Target indicator (Joliff et al., 2010) for quantitatively estimating model performances in air quality modelling applications. This work presents this methodology applied to NO2, O3 and PM10 concentrations on three different model-observations datasets.
A PC-oriented Emergency Response System in case of nuclear accident (BERS) has been developed and... more A PC-oriented Emergency Response System in case of nuclear accident (BERS) has been developed and works operationally at the Bulgarian National Institute of Meteorology and Hydrology (NIMH). The creation and the development of BERS was highly stimulated by the ETEX (European Tracer EХperiment) project. BERS comprises two main parts operational and accidental ones. The operational part runs automatically every day. It prepares the input meteorological file used by both trajectory and dispersion models, runs the trajectory model for 35 European Nuclear Power Plants (NPP), visualizes the results and uploads the maps of trajectories to a dedicated web-site. The accidental part is activated manually when a real radioactive release occurs or during emergency exercises. Its core is the Bulgarian dispersion model EMAP. Outputs are time sequences of concentration and accumulated deposition fields. In the paper, the new version of BERS regarding mainly the operational part is presented. The m...
Air pollution continues to be of concern for Bulgarian cities, mainly due to particulate matter o... more Air pollution continues to be of concern for Bulgarian cities, mainly due to particulate matter of aerodynamic diameter smaller than 10 μm (PM10). There is public and expert interest in the improvement of two operational air quality modeling systems: the Bulgarian Chemical Weather Forecast System (BgCWFS) and the Local Air Quality Management System (LAQMS) for the city of Plovdiv. The aim of the study is to investigate the effects of satellite data assimilation in BgCWFS on surface concentrations over Bulgaria (resolution 9 km), to downscale BgCWFS output to LAQMS (resolution 250 m), and to examine effects on PM10 in Plovdiv. Data from the Global Ozone Monitoring Experiment-2 (GOME-2) (MetOP satellites) for aerosols, nitrogen dioxide (NO2), and sulfur dioxide (SO2) were assimilated in BgCWFS using objective analysis. Simulation experiments with and without satellite data were conducted for a summer and a winter month. The comparison to surface observations in the country showed impr...
The air is the living environment of human beings and obviously the atmospheric composition has a... more The air is the living environment of human beings and obviously the atmospheric composition has a great importance for the quality of life and human health. Air Quality (AQ) is a key element for the well-being and quality of life of European citizens. The objectives of the present work is performing reliable, comprehensive and detailed studies of the impact of lower atmosphere composition on the quality of life and health risks for the population in Bulgaria. The study of AQ is based on atmospheric composition numerical simulations. This is a fruitful approach, which will helps better understanding of the part which different processes and transport scales play in Air Environment formation. The Air Quality Index (AQI) provides an integrated assessment of the impact of air pollutants on human health and is calculated on the basis of the concentration of various pollutants obtained from measurements or numerical modelling. The following set of models was applied as basic tool for 3D s...
The air quality modelling system WRF-CMAQ running at the National Institute of Meteorology and Hy... more The air quality modelling system WRF-CMAQ running at the National Institute of Meteorology and Hydrology (NIMH) in Sofia was applied to the European domain for the year 2010 in the frame of the Air Quality Model Evaluation International Initiative (AQMEII), Phase 2. The model system was set up for a domain of 5000x5000 km2 size with horizontal resolution of 25 km. The models’ options used and the emission input are briefly outlined. The model performance was investigated based on graphical plots and statistical indexes obtained by the web-based model evaluation platform ENSEMBLE. A preliminary operational model evaluation for ozone and particulate matter was conducted, comparing simulated and observed concentrations at ground level in three sub-domains of Europe. The analysis shows model overestimation for ozone and model underestimation for particulate matter. The best statistical indicators are for ozone concentrations during summer, when comparing data for EMEP stations in the EU...
The air quality modelling system WRF-CMAQ was applied by the Bulgarian NIMH (National Institute f... more The air quality modelling system WRF-CMAQ was applied by the Bulgarian NIMH (National Institute for Meteorology and Hydrology) team to the European domain in the frame of the Air Quality Model Evaluation International Initiative, Phase 2 (AQMEII-2). The model system was set up for the European domain of 5000×5000 km size with horizontal resolution of 25 km. The emissions were available through AQMEII and further processed in a way to feed the chemistry transport model CMAQ. The meso-meteorological model WRF was driven by NCEP GFS data with 1°×1° resolution. The chemical boundary conditions were extracted from MACC global simulation data. Model performance was investigated by means of AQMEII-2 web-based evaluation platform ENSEMBLE. A preliminary model evaluation for ozone and particulate matter was conducted based on comparison between simulated and observed concentrations at different type of surface stations in the EU wide domain. Model performance was characterized by overestimat...
Model evaluation is performed based on comparison of simulated and observed air pollution concent... more Model evaluation is performed based on comparison of simulated and observed air pollution concentrations at 25 background stations of the Bulgarian national air quality monitoring network for the year 2013. The DELTA software package, developed within the forum for air quality modelling in Europe - FAIRMODE, is used to analyse model results focusing on maximum daily eight-hour mean ozone concentrations, hourly nitrogen dioxide (NO2) and daily particulate matter (PM10) concentrations. Ozone is overestimated by 38%, minimum daily values are overestimated by a factor of 3. NO2 and PM10 are underestimated by a factor of, respectively, 4 and (5 to 9). The main DELTA model quality objective is respected at 26% of the stations for ozone, 58% of the stations for NO2, and nowhere for PM10. The best model performance is for ozone at rural sites during summer. Possible ways for improvement of model results are discussed.
The planetary boundary-layer (PBL) parameterization is a key issue for the definition of initial ... more The planetary boundary-layer (PBL) parameterization is a key issue for the definition of initial wind flow fields in diagnostic models. However, PBL theories usually treat separately stable, neutral, and convective stability conditions, so that their implementation in diagnostic wind models is not straightforward. In the present paper, an attempt is made to adopt a comprehensive PBL parameterisation, covering stable/neutral and unstable atmospheric conditions, which appears suitable to diagnostic models. This parameterisation is implemented into our diagnostic mass-consistent code. A validation of the consistency between the implemented PBL parameterisations has been checked through an analysis of the sensitivity of the vertical wind profiles to atmospheric stability.
Atmospheric deposition processes are of primary importance for human health, forests, agricultura... more Atmospheric deposition processes are of primary importance for human health, forests, agricultural lands, aquatic bodies, and ecosystems. South-East Europe is still characterized by numerous hot spots of elevated sulfur deposition, despite the reduction in European emission sources. The purpose of this study is to discuss the results from two chemical transport models and observations for wet and dry depositions of sulfur (S), reduced nitrogen (RDN) and oxidized nitrogen (OXN) in Bulgaria in 2016–2017. The spatial distribution and the domain main deposition values by EMEP MSC-W (model of the MSC-W Centre of the Co-operative Programme for Monitoring and Evaluation of the Long-range Transmissions of Air Pollutants in Europe) and BgCWFS (Bulgarian Chemical Weather Forecast System) demonstrated S wet depositions to be higher than N depositions, and identified a rural area in south-east Bulgaria as a possible hot-spot. The chemical analysis of deposition samples at three sites showed a p...
The main objective of this study is to evaluate the performance of some well-known and widely use... more The main objective of this study is to evaluate the performance of some well-known and widely used operational air quality modelling systems (EMEP-MSC-W, and the models at the Copernicus Atmosphere Monitoring Service (CAMS)) for simulations of particulate matter in Bulgaria. The analysis is focussed on a summer month (August 2017) and includes comparison of model to observations from 24 regular air quality background stations, as well as model inter-comparison. Along with statistical indicators various graphs are used – box plots, kernel density estimations,and scatter plots. The spatial distribution is discussed upon maps of monthly mean concentrations and comparison of domain averaged model concentrations. The spatial distribution of PM10 is similar only over the Black sea. The highest domain mean surface concentrations are simulated by CAMS global – by about 12 % for PM10 and by about 14 % for PM2.5 higher than the other models.
Black carbon (BC) is one of the particulate matter (PM) components that both affects human health... more Black carbon (BC) is one of the particulate matter (PM) components that both affects human health and contributes to climate change. In this study, we present the preliminary results of the investigation of BC concentrations in PM2.5 for two Bulgarian cites—Sofia and Burgas. The parallel PM2.5 samplings were organized in October 2020 and January 2021. The Multi-Wavelength Absorption Black carbon Instrument (MABI) was used for the evaluation of light-absorbing carbon. In addition, we compared the observed BC and PM2.5 values to modelled ones and analyzed the spatial distribution over the country, using data from advanced operational chemical transport models (CTM)—the European (regional) air quality system established at the Copernicus Atmosphere Monitoring Service (CAMS). Generally, the observed BC and PM2.5 values were higher in January than in October for both cities. In October, the model underestimated the observed BC concentrations (Sofia—2.44 μg.m−3, Burgas—1.63 μg.m−3) by 17%...
As part of the FAIRMODE benchmarking activities (Thunis et al., 2010), performance criteria for a... more As part of the FAIRMODE benchmarking activities (Thunis et al., 2010), performance criteria for air quality modelling in the frame of the EU Air Quality directive (AQD) 2008 are proposed and tested. The suggested approach builds on the Target indicator (Joliff et al., 2010) for quantitatively estimating model performances in air quality modelling applications. This work presents this methodology applied to NO2, O3 and PM10 concentrations on three different model-observations datasets.
A PC-oriented Emergency Response System in case of nuclear accident (BERS) has been developed and... more A PC-oriented Emergency Response System in case of nuclear accident (BERS) has been developed and works operationally at the Bulgarian National Institute of Meteorology and Hydrology (NIMH). The creation and the development of BERS was highly stimulated by the ETEX (European Tracer EХperiment) project. BERS comprises two main parts operational and accidental ones. The operational part runs automatically every day. It prepares the input meteorological file used by both trajectory and dispersion models, runs the trajectory model for 35 European Nuclear Power Plants (NPP), visualizes the results and uploads the maps of trajectories to a dedicated web-site. The accidental part is activated manually when a real radioactive release occurs or during emergency exercises. Its core is the Bulgarian dispersion model EMAP. Outputs are time sequences of concentration and accumulated deposition fields. In the paper, the new version of BERS regarding mainly the operational part is presented. The m...
Air pollution continues to be of concern for Bulgarian cities, mainly due to particulate matter o... more Air pollution continues to be of concern for Bulgarian cities, mainly due to particulate matter of aerodynamic diameter smaller than 10 μm (PM10). There is public and expert interest in the improvement of two operational air quality modeling systems: the Bulgarian Chemical Weather Forecast System (BgCWFS) and the Local Air Quality Management System (LAQMS) for the city of Plovdiv. The aim of the study is to investigate the effects of satellite data assimilation in BgCWFS on surface concentrations over Bulgaria (resolution 9 km), to downscale BgCWFS output to LAQMS (resolution 250 m), and to examine effects on PM10 in Plovdiv. Data from the Global Ozone Monitoring Experiment-2 (GOME-2) (MetOP satellites) for aerosols, nitrogen dioxide (NO2), and sulfur dioxide (SO2) were assimilated in BgCWFS using objective analysis. Simulation experiments with and without satellite data were conducted for a summer and a winter month. The comparison to surface observations in the country showed impr...
The air is the living environment of human beings and obviously the atmospheric composition has a... more The air is the living environment of human beings and obviously the atmospheric composition has a great importance for the quality of life and human health. Air Quality (AQ) is a key element for the well-being and quality of life of European citizens. The objectives of the present work is performing reliable, comprehensive and detailed studies of the impact of lower atmosphere composition on the quality of life and health risks for the population in Bulgaria. The study of AQ is based on atmospheric composition numerical simulations. This is a fruitful approach, which will helps better understanding of the part which different processes and transport scales play in Air Environment formation. The Air Quality Index (AQI) provides an integrated assessment of the impact of air pollutants on human health and is calculated on the basis of the concentration of various pollutants obtained from measurements or numerical modelling. The following set of models was applied as basic tool for 3D s...
The air quality modelling system WRF-CMAQ running at the National Institute of Meteorology and Hy... more The air quality modelling system WRF-CMAQ running at the National Institute of Meteorology and Hydrology (NIMH) in Sofia was applied to the European domain for the year 2010 in the frame of the Air Quality Model Evaluation International Initiative (AQMEII), Phase 2. The model system was set up for a domain of 5000x5000 km2 size with horizontal resolution of 25 km. The models’ options used and the emission input are briefly outlined. The model performance was investigated based on graphical plots and statistical indexes obtained by the web-based model evaluation platform ENSEMBLE. A preliminary operational model evaluation for ozone and particulate matter was conducted, comparing simulated and observed concentrations at ground level in three sub-domains of Europe. The analysis shows model overestimation for ozone and model underestimation for particulate matter. The best statistical indicators are for ozone concentrations during summer, when comparing data for EMEP stations in the EU...
The air quality modelling system WRF-CMAQ was applied by the Bulgarian NIMH (National Institute f... more The air quality modelling system WRF-CMAQ was applied by the Bulgarian NIMH (National Institute for Meteorology and Hydrology) team to the European domain in the frame of the Air Quality Model Evaluation International Initiative, Phase 2 (AQMEII-2). The model system was set up for the European domain of 5000×5000 km size with horizontal resolution of 25 km. The emissions were available through AQMEII and further processed in a way to feed the chemistry transport model CMAQ. The meso-meteorological model WRF was driven by NCEP GFS data with 1°×1° resolution. The chemical boundary conditions were extracted from MACC global simulation data. Model performance was investigated by means of AQMEII-2 web-based evaluation platform ENSEMBLE. A preliminary model evaluation for ozone and particulate matter was conducted based on comparison between simulated and observed concentrations at different type of surface stations in the EU wide domain. Model performance was characterized by overestimat...
Model evaluation is performed based on comparison of simulated and observed air pollution concent... more Model evaluation is performed based on comparison of simulated and observed air pollution concentrations at 25 background stations of the Bulgarian national air quality monitoring network for the year 2013. The DELTA software package, developed within the forum for air quality modelling in Europe - FAIRMODE, is used to analyse model results focusing on maximum daily eight-hour mean ozone concentrations, hourly nitrogen dioxide (NO2) and daily particulate matter (PM10) concentrations. Ozone is overestimated by 38%, minimum daily values are overestimated by a factor of 3. NO2 and PM10 are underestimated by a factor of, respectively, 4 and (5 to 9). The main DELTA model quality objective is respected at 26% of the stations for ozone, 58% of the stations for NO2, and nowhere for PM10. The best model performance is for ozone at rural sites during summer. Possible ways for improvement of model results are discussed.
The planetary boundary-layer (PBL) parameterization is a key issue for the definition of initial ... more The planetary boundary-layer (PBL) parameterization is a key issue for the definition of initial wind flow fields in diagnostic models. However, PBL theories usually treat separately stable, neutral, and convective stability conditions, so that their implementation in diagnostic wind models is not straightforward. In the present paper, an attempt is made to adopt a comprehensive PBL parameterisation, covering stable/neutral and unstable atmospheric conditions, which appears suitable to diagnostic models. This parameterisation is implemented into our diagnostic mass-consistent code. A validation of the consistency between the implemented PBL parameterisations has been checked through an analysis of the sensitivity of the vertical wind profiles to atmospheric stability.
Uploads