bojan cvetkovic | University of Belgrade (original) (raw)

Papers by bojan cvetkovic

EPJ Web of Conferences, 2018

By means of available ice nucleating particle (INP) parameterization schemes we compute profiles ... more By means of available ice nucleating particle (INP) parameterization schemes we compute profiles of dust INP number concentration utilizing Polly-XT and CALIPSO lidar observations during the INUIT-BACCHUS-ACTRIS 2016 campaign. The polarization-lidar photometer networking (POLIPHON) method is used to separate dust and non-dust aerosol backscatter, extinction, mass concentration, particle number concentration (for particles with radius > 250 nm) and surface area concentration. The INP final products are compared with aerosol samples collected from unmanned aircraft systems (UAS) and analyzed using the ice nucleus counter FRIDGE.

During an intensive field campaign on aerosol, clouds, and ice nucleation in the Eastern Mediterr... more During an intensive field campaign on aerosol, clouds, and ice nucleation in the Eastern Mediterranean in April 2016, we measured the abundance of ice nucleating particles (INPs) in the lower troposphere from unmanned aircraft systems (UASs). Aerosol samples were collected by miniaturized electrostatic precipitators onboard the UASs at altitudes up to 2.5 km. The number of INPs in these samples, which are active in the deposition and condensation modes at temperatures from −20 to −30 • C, were analyzed immediately after collection on site using the ice nucleus counter FRIDGE (FRankfurt Ice nucleation Deposition freezinG Experiment). During the 1-month campaign, we encountered a series of Saharan dust plumes that traveled at several kilometers' altitude. Here we present INP data from 42 individual flights, together with aerosol number concentrations, observations of lidar backscattering, dust concentrations derived by the dust transport model DREAM (Dust Regional Atmospheric Model), and results from scanning electron microscopy. The effect of the dust plumes is reflected by the coincidence of INPs with the particulate matter (PM), the lidar signal, and the predicted dust mass of the model. This suggests that mineral dust or a constituent related to dust was a major contributor to the ice nucleating properties of the aerosol. Peak concentrations of above 100 INPs std L −1 were measured at −30 • C. The INP concentration in elevated plumes was on average a factor of 10 higher than at ground level. Since desert dust is transported for long distances over wide areas of the globe predominantly at several kilometers' altitude, we conclude that INP measurements at ground level may be of limited significance for the situation at the level of cloud formation.

Dust aerosols are very efficient ice nuclei important for heterogeneous cloud glaciation even in ... more Dust aerosols are very efficient ice nuclei important for heterogeneous cloud glaciation even in regions distant from desert sources. A new generation of ice nucleation parameterizations, including dust as ice nucleation agent, opens the way towards a more accurate treatment of cold cloud formation in atmospheric models. Using such parameterizations, we have developed a regional dust-atmospheric modelling system capable to predict in real-time conditions dust-induced ice nucleation. We executed the model with added ice nucleation component over the Mediterranean region, exposed to moderate Saharan dust transport over two periods lasting 15 and 9 days, respectively. Model results are validated against satellite and ground-based cloud-ice-related measurements, provided by SEVIRI (Spinning Enhanced Visible and InfraRed Imager) and by the CNR-IMAA Atmospheric Observatory CIAO in Potenza, South Italy. Predicted ice nuclei concentration shows reasonable level of agreement when compared against observed spatial and temporal patterns of cloud ice water. The developed methodology permits to use ice nuclei as input into cloud microphysics schemes of atmospheric models, expecting that this approach could improve predictions of cloud formation and associated precipitation. 1 Introduction Aerosol acting as ice nucleating particles () enhances the heterogeneous glaciation of cloud water making it to freeze earlier and at higher temperatures than otherwise. Insoluble particles such as dust and biological particles are known

Atmospheric Chemistry and Physics, 2016

EPJ Web of Conferences, 2018

By means of available ice nucleating particle (INP) parameterization schemes we compute profiles ... more By means of available ice nucleating particle (INP) parameterization schemes we compute profiles of dust INP number concentration utilizing Polly-XT and CALIPSO lidar observations during the INUIT-BACCHUS-ACTRIS 2016 campaign. The polarization-lidar photometer networking (POLIPHON) method is used to separate dust and non-dust aerosol backscatter, extinction, mass concentration, particle number concentration (for particles with radius > 250 nm) and surface area concentration. The INP final products are compared with aerosol samples collected from unmanned aircraft systems (UAS) and analyzed using the ice nucleus counter FRIDGE.

During an intensive field campaign on aerosol, clouds, and ice nucleation in the Eastern Mediterr... more During an intensive field campaign on aerosol, clouds, and ice nucleation in the Eastern Mediterranean in April 2016, we measured the abundance of ice nucleating particles (INPs) in the lower troposphere from unmanned aircraft systems (UASs). Aerosol samples were collected by miniaturized electrostatic precipitators onboard the UASs at altitudes up to 2.5 km. The number of INPs in these samples, which are active in the deposition and condensation modes at temperatures from −20 to −30 • C, were analyzed immediately after collection on site using the ice nucleus counter FRIDGE (FRankfurt Ice nucleation Deposition freezinG Experiment). During the 1-month campaign, we encountered a series of Saharan dust plumes that traveled at several kilometers' altitude. Here we present INP data from 42 individual flights, together with aerosol number concentrations, observations of lidar backscattering, dust concentrations derived by the dust transport model DREAM (Dust Regional Atmospheric Model), and results from scanning electron microscopy. The effect of the dust plumes is reflected by the coincidence of INPs with the particulate matter (PM), the lidar signal, and the predicted dust mass of the model. This suggests that mineral dust or a constituent related to dust was a major contributor to the ice nucleating properties of the aerosol. Peak concentrations of above 100 INPs std L −1 were measured at −30 • C. The INP concentration in elevated plumes was on average a factor of 10 higher than at ground level. Since desert dust is transported for long distances over wide areas of the globe predominantly at several kilometers' altitude, we conclude that INP measurements at ground level may be of limited significance for the situation at the level of cloud formation.

Dust aerosols are very efficient ice nuclei important for heterogeneous cloud glaciation even in ... more Dust aerosols are very efficient ice nuclei important for heterogeneous cloud glaciation even in regions distant from desert sources. A new generation of ice nucleation parameterizations, including dust as ice nucleation agent, opens the way towards a more accurate treatment of cold cloud formation in atmospheric models. Using such parameterizations, we have developed a regional dust-atmospheric modelling system capable to predict in real-time conditions dust-induced ice nucleation. We executed the model with added ice nucleation component over the Mediterranean region, exposed to moderate Saharan dust transport over two periods lasting 15 and 9 days, respectively. Model results are validated against satellite and ground-based cloud-ice-related measurements, provided by SEVIRI (Spinning Enhanced Visible and InfraRed Imager) and by the CNR-IMAA Atmospheric Observatory CIAO in Potenza, South Italy. Predicted ice nuclei concentration shows reasonable level of agreement when compared against observed spatial and temporal patterns of cloud ice water. The developed methodology permits to use ice nuclei as input into cloud microphysics schemes of atmospheric models, expecting that this approach could improve predictions of cloud formation and associated precipitation. 1 Introduction Aerosol acting as ice nucleating particles () enhances the heterogeneous glaciation of cloud water making it to freeze earlier and at higher temperatures than otherwise. Insoluble particles such as dust and biological particles are known

Atmospheric Chemistry and Physics, 2016