Biological and dust aerosols as sources of ice-nucleating particles in the eastern Mediterranean: source apportionment, atmospheric processing and parameterization DOI Creative Commons
Kunfeng Gao, Franziska Vogel, Romanos Foskinis

et al.

Atmospheric chemistry and physics, Journal Year: 2024, Volume and Issue: 24(17), P. 9939 - 9974

Published: Sept. 9, 2024

Abstract. Aerosol–cloud interactions in mixed-phase clouds (MPCs) are one of the most uncertain drivers hydrological cycle and climate change. A synergy situ, remote-sensing modelling experiments were used to determine source ice-nucleating particles (INPs) for MPCs at Mount Helmos eastern Mediterranean. The influences boundary layer turbulence, vertical aerosol distributions meteorological conditions also examined. When observation site is free troposphere (FT), approximately 1 ×106 serve as INPs around −25 °C. INP abundance spans 3 orders magnitude increases following order: marine aerosols; continental and, finally, dust plumes. Biological important observed aerosols, whereas they play a secondary, although important, role during Saharan events. Air masses planetary (PBL) show both enriched concentrations higher proportion total particles, compared with cases FT. presence precipitation/clouds enriches FT but decreases PBL. Additionally, new parameterizations developed that incorporate ratio fluorescent-to-nonfluorescent or coarse-to-fine predict >90 % within an uncertainty range factor 10; these exhibit better performance than current widely allow ice formation models respond variations biological particles. improved can help MPC simulations regions various sources different prevailing sources.

Language: Английский

High-altitude aerosol chemical characterization and source identification: insights from the CALISHTO campaign DOI Creative Commons
Olga Zografou, Maria Gini, Prodromos Fetfatzis

et al.

Atmospheric chemistry and physics, Journal Year: 2024, Volume and Issue: 24(15), P. 8911 - 8926

Published: Aug. 15, 2024

Abstract. The Cloud-AerosoL InteractionS in the Helmos background TropOsphere (CALISHTO) campaign took place autumn 2021 at NCSR Demokritos high-altitude Hellenic Atmospheric Aerosol and Climate Change station (HAC)2 to study interactions between aerosols clouds. current presents chemical characterization of non-refractory (NR) PM1 aerosol fraction using a time-of-flight speciation monitor (ToF-ACSM). A comparative offline filter analysis by high-resolution mass spectrometer (HR-ToF-AMS) showed consistent results regarding species determined. Source apportionment applied on both datasets (ACSM-ToF AMS extracts) yielded same factors for organic (one primary two secondary factors). Additionally, positive matrix factorization (PMF) model was total ToF-ACSM (including inorganic ions). Five different types were identified, including factor; ammonium nitrate; sulfate; aerosols, one more oxidized less oxidized. prevailing atmospheric conditions station, i.e., cloud presence, influence emissions from planetary boundary layer (PBL), air origin, also incorporated study. segregation PBL free-troposphere (FT) made combining data remote sensing situ measurement techniques. masses arriving site grouped as continental, marine, dust, marine–dust based back-trajectory data. Significant temporal variability characteristics observed throughout campaign; September, within sampled most time, resulting much higher concentrations compared October November when reduced factor 5. Both in-cloud FT periods resulted lower concentration levels, while similar composition conditions. We take advantage recently developed “virtual-filtering” technique separate interstitial activated PM10 inlet during cloudy periods. This allows determination Ammonium sulfate, dominant PMF all conditions, contributed dust events, contribution arrived continental Europe.

Language: Английский

Citations

4
On the drivers of ice nucleating particle diurnal variability in Eastern Mediterranean clouds DOI Creative Commons
Kunfeng Gao, Franziska Vogel, Romanos Foskinis

et al.

npj Climate and Atmospheric Science, Journal Year: 2025, Volume and Issue: 8(1)

Published: May 5, 2025

Abstract We report the drivers of spatiotemporal variability ice nucleating particles (INPs) for mixed-phase orographic clouds (~−25 °C) in Eastern Mediterranean. In planetary boundary layer, pronounced INP diurnal periodicity is observed, which mainly driven by biological (and to a lesser extent, dust) but not aerosols from biomass burning. The comparison size-resolved and fluorescence-discriminated aerosol particle properties with INPs reveals primary role fluorescent bioaerosol. presence Saharan dust increases during nighttime more than daytime, because lower layer height decreases contribution (including bioaerosols) layer. absent free troposphere, although levels are availability bioaerosol particles. Given effective nucleation ability bioaerosols subsequent effects multiplication at warm temperatures, lack such cycles models points important overlooked cloud formation precipitation mountainous regions.

Language: Английский

Citations

0
Drivers of droplet formation in east Mediterranean orographic clouds DOI Creative Commons
Romanos Foskinis, Ghislain Motos, Maria Gini

et al.

Atmospheric chemistry and physics, Journal Year: 2024, Volume and Issue: 24(17), P. 9827 - 9842

Published: Sept. 5, 2024

Abstract. The purpose of this study is to understand the drivers cloud droplet formation in orographic clouds. We used a combination modeling, situ, and remote sensing measurements at high-altitude Helmos Hellenic Atmospheric Aerosol Climate Change ((HAC)2) station, which located top Mt. (1314 m above sea level), Greece, during Cloud–AerosoL InteractionS Background TropOsphere (CALISHTO) campaign fall 2021 (https://calishto.panacea-ri.gr/, last access: 1 August 2024) examine origins aerosols (i.e., local aerosol from planetary boundary layer (PBL) or long-range-transported free-tropospheric (FTL) contributing condensation nuclei (CCN)), their characteristics (hygroscopicity, size distribution, mixing state), vertical velocity distributions resulting supersaturations. found that PBL were considerably different FTL use particle number equivalent mass concentration black carbon (eBC) order determine when (HAC)2 was within based on time series height PBL. During events we sample mixture interstitial residues, characterize using new approach utilizes situ periods purely interstitial. From dataset properties (size distribution hygroscopicity) pre-cloud, activated, aerosol. hygroscopicity activated be higher than pre-cloud A closure studies with parameterization shows (Nd) supersaturation can predicted 25 % observations correspond conditions. analysis characteristic each population indicates clouds aerosol-limited formed air masses – hence driven by variations, while tend velocity-limited variations are fluctuations velocity. Given dynamics do not vary significantly between masses, variation type mostly responsible for these shifts microphysical state sensitivity With insights, droplets such infer either CCN spectra (when FTL) PBL). In conclusion, show coordinated measurement properties, together novel approaches presented here, allows determination variations.

Language: Английский

Citations

1
Biological and dust aerosols as sources of ice-nucleating particles in the eastern Mediterranean: source apportionment, atmospheric processing and parameterization DOI Creative Commons
Kunfeng Gao, Franziska Vogel, Romanos Foskinis

et al.

Atmospheric chemistry and physics, Journal Year: 2024, Volume and Issue: 24(17), P. 9939 - 9974

Published: Sept. 9, 2024

Abstract. Aerosol–cloud interactions in mixed-phase clouds (MPCs) are one of the most uncertain drivers hydrological cycle and climate change. A synergy situ, remote-sensing modelling experiments were used to determine source ice-nucleating particles (INPs) for MPCs at Mount Helmos eastern Mediterranean. The influences boundary layer turbulence, vertical aerosol distributions meteorological conditions also examined. When observation site is free troposphere (FT), approximately 1 ×106 serve as INPs around −25 °C. INP abundance spans 3 orders magnitude increases following order: marine aerosols; continental and, finally, dust plumes. Biological important observed aerosols, whereas they play a secondary, although important, role during Saharan events. Air masses planetary (PBL) show both enriched concentrations higher proportion total particles, compared with cases FT. presence precipitation/clouds enriches FT but decreases PBL. Additionally, new parameterizations developed that incorporate ratio fluorescent-to-nonfluorescent or coarse-to-fine predict >90 % within an uncertainty range factor 10; these exhibit better performance than current widely allow ice formation models respond variations biological particles. improved can help MPC simulations regions various sources different prevailing sources.

Language: Английский

Citations

1