Technique for the introduction into the atmosphere of high concentrations of electrically charged aerosol particles

Abstract. We have measured the size distributions of air ions (0.42–7.5 nm in diameter) with the Balanced Scanning Mobility Analyzer in boreal forest, in Southern Finland since spring 2003. The size range covers the size range of cluster ions (approximately 0.42–1.6 nm) and naturally charged nanometre aerosol particles (1.6–7.5 nm) or intermediate air ions. Based on the measurements from April 2003 to March 2006 we studied the characteristics of charged aerosol particle formation by classifying each day either as a particle formation event, undefined or non-event day. The principal of the classification, as well as the statistical description of the charged aerosol particle formation events are given. We found in total 270 (26% of the analysed days) and 226 (22% of the analysed days) particle formation days for negative and positive intermediate ions, respectively. For negatively charged particles we classified 411 (40% of the analysed days) undefined and 348 (34% of the analysed days) non-event days whereas for positively charged particles 343 (33% of the analysed days) undefined and 460 (45% of the analysed days) non-event days. The results were compared with the ordinary classification based on the Differential Mobility Particle Sizer (DMPS) measurements carried out at the same place. The above-presented values differed slightly from that found from the DMPS data, with a lower particle diameter of 3 nm. In addition, we have found the rain-induced intermediate ion bursts frequently. The rain effect was detected on 163 days by means of negative ions and on 105 days by positive ones. Another interesting phenomenon among the charged aerosol particles was the appearance and existence of intermediate ions during the snowfall. We observed this phenomenon 24 times with negatively charged particles and 21 times with positively charged ones during winter months (October–April). These intermediate air ions were seen during the snowfall and may be caused by ice crystals, although the origin of these intermediate ions is unclear at the moment.

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Ice-nucleating particles in a coastal tropical site

Atmospheric Chemistry and Physics ◽

10.5194/acp-19-6147-2019 ◽

2019 ◽

Vol 19 (9) ◽

pp. 6147-6165 ◽

Cited By ~ 4

Author(s):

Luis A. Ladino ◽

Graciela B. Raga ◽

Harry Alvarez-Ospina ◽

Manuel A. Andino-Enríquez ◽

Irma Rosas ◽

...

Keyword(s):

Pseudomonas Syringae ◽

Hydrological Cycle ◽

Aerosol Particles ◽

Relevant Information ◽

Dust Particles ◽

Data Sets ◽

Tropical Regions ◽

Need To Evaluate ◽

High Concentrations ◽

Few Data

Abstract. Atmospheric aerosol particles that can nucleate ice are referred to as ice-nucleating particles (INPs). Recent studies have confirmed that aerosol particles emitted by the oceans can act as INPs. This very relevant information can be included in climate and weather models to predict the formation of ice in clouds, given that most of them do not consider oceans as a source of INPs. Very few studies that sample INPs have been carried out in tropical latitudes, and there is a need to evaluate their availability to understand the potential role that marine aerosol may play in the hydrological cycle of tropical regions. This study presents results from the first measurements obtained during a field campaign conducted in the tropical village of Sisal, located on the coast of the Gulf of Mexico of the Yucatan Peninsula in Mexico in January–February 2017, and one of the few data sets currently available at such latitudes (i.e., 21∘ N). Aerosol particles sampled in Sisal are shown to be very efficient INPs in the immersion freezing mode, with onset freezing temperatures in some cases as high as −3 ∘C, similarly to the onset temperature from Pseudomonas syringae. The results show that the INP concentration in Sisal was higher than at other locations sampled with the same type of INP counter. Air masses arriving in Sisal after the passage of cold fronts have surprisingly higher INP concentrations than the campaign average, despite their lower total aerosol concentration. The high concentrations of INPs at warmer ice nucleation temperatures (T>-15 ∘C) and the supermicron size of the INPs suggest that biological particles may have been a significant contributor to the INP population in Sisal during this study. However, our observations also suggest that at temperatures ranging between −20 and −30 ∘C mineral dust particles are the likely source of the measured INPs.

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3D Nanoprinting with Charged Aerosol Particles—An Overview

Accounts of Materials Research ◽

10.1021/accountsmr.1c00187 ◽

2021 ◽

Author(s):

Wooik Jung ◽

Peter V. Pikhitsa ◽

Yoon-Ho Jung ◽

Jooyeon Shin ◽

Minsung Han ◽

...

Keyword(s):

Aerosol Particles ◽

Charged Aerosol

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Variation and balance of positive air ion concentrations in a boreal forest

Atmospheric Chemistry and Physics ◽

10.5194/acp-8-655-2008 ◽

2008 ◽

Vol 8 (3) ◽

pp. 655-675 ◽

Cited By ~ 34

Author(s):

U. Hõrrak ◽

P. P. Aalto ◽

J. Salm ◽

K. Komsaare ◽

H. Tammet ◽

...

Keyword(s):

Steady State ◽

Boreal Forest ◽

Correlation Coefficient ◽

Aerosol Particles ◽

Coniferous Forest ◽

Ionization Rate ◽

Ion Concentration ◽

Air Ions ◽

Ion Concentrations ◽

Charged Aerosol

Abstract. Air ions are characterized on the basis of measurements carried out in a boreal forest at the Hyytiälä SMEAR station, Finland, during the BIOFOR III campaign in spring 1999. The air ions were discriminated as small ions (charged molecular aggregates of the diameter of less than 2.5 nm), intermediate ions (charged aerosol particles of the diameter of 2.5–8 nm), and large ions (charged aerosol particles of the diameter of 8–20 nm). Statistical characteristics of the ion concentrations and the parameters of ion balance in the atmosphere are presented separately for the nucleation event days and non-event days. In the steady state, the ionization rate is balanced with the loss of small ions, which is expressed as the product of the small ion concentration and the ion sink rate. The widely known sinks of small ions are the recombination with small ions of opposite polarity and attachment to aerosol particles. The dependence of small ion concentration on the concentration of aerosol particles was investigated applying a model of the bipolar diffusion charging of particles by small ions. When the periods of relative humidity above 95% and wind speed less than 0.6 m s−1 were excluded, then the small ion concentration and the theoretically calculated small ion sink rate were closely negatively correlated (correlation coefficient −87%). However, an extra ion loss term of the same magnitude as the ion loss onto aerosol particles is needed for a quantitative explanation of the observations. This term is presumably due to the small ion deposition on coniferous forest. The hygroscopic growth correction of the measured aerosol particle size distributions was also found to be necessary for the proper estimation of the ion sink rate. In the case of nucleation burst events, the concentration of small positive ions followed the general balance equation, no extra ion loss in addition to the deposition on coniferous forest was detected, and the hypothesis of the conversion of ions into particles in the process of ion-induced nucleation was not proved. The estimated average ionization rate of the air at the Hyytiälä station in early spring, when the ground was partly covered with snow, was about 6 ion pairs cm−3 s−1. The study of the charging state of nanometer aerosol particles (diameter 2.5–8 nm) in the atmosphere revealed a strong correlation (correlation coefficient 88%) between the concentrations of particles neutralized in the aerosol spectrometer and naturally positively charged particles (air ions) during nucleation bursts. The charged fraction of particles varied from 3% to 6% in accordance with the hypothesis that the particles are quasi-steady state charged.

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The ECOMA 2007 campaign: rocket observations and numerical modelling of aerosol particle charging and plasma depletion in a PMSE/NLC layer

Annales Geophysicae ◽

10.5194/angeo-27-781-2009 ◽

2009 ◽

Vol 27 (2) ◽

pp. 781-796 ◽

Cited By ~ 17

Author(s):

A. Brattli ◽

Ø. Lie-Svendsen ◽

K. Svenes ◽

U.-P. Hoppe ◽

I. Strelnikova ◽

...

Keyword(s):

Aerosol Particle ◽

Aerosol Particles ◽

Pure Water ◽

Ion Density ◽

Ambient Plasma ◽

Water Ice ◽

Charged Aerosol ◽

Summer Echoes ◽

Polar Mesosphere Summer Echoes ◽

Positively Charged

Abstract. The ECOMA series of rocket payloads use a set of aerosol particle, plasma, and optical instruments to study the properties of aerosol particles and their interaction with the ambient plasma environment in the polar mesopause region. In August 2007 the ECOMA-3 payload was launched into a region with Polar Mesosphere Summer Echoes (PMSE) and noctilucent clouds (NLC). An electron depletion was detected in a broad region between 83 and 88 km, coincident with enhanced density of negatively charged aerosol particles. We also find evidence for positive ion depletion in the same region. Charge neutrality requires that a population of positively charged particles smaller than 2 nm and with a density of at least 2×108 m−3 must also have been present in the layer, undetected by the instruments. A numerical model for the charging of aerosol particles and their interaction with the ambient plasma is used to analyse the results, showing that high aerosol particle densities are required in order to explain the observed ion density depletion. The model also shows that a very high photoionisation rate is required for the particles smaller than 2 nm to become positively charged, indicating that these may have a lower work function than pure water ice.

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Estimation of the agglomeration coefficient of bipolar-charged aerosol particles

Journal of Electrostatics ◽

10.1016/s0304-3886(99)00053-4 ◽

2000 ◽

Vol 48 (2) ◽

pp. 93-101 ◽

Cited By ~ 24

Author(s):

Y. Koizumi ◽

M. Kawamura ◽

F. Tochikubo ◽

T. Watanabe

Keyword(s):

Aerosol Particles ◽

Charged Aerosol ◽

Agglomeration Coefficient

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