Journal cover Journal topic
Atmospheric Chemistry and Physics An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

Journal metrics

  • IF value: 5.414 IF 5.414
  • IF 5-year value: 5.958 IF 5-year
    5.958
  • CiteScore value: 9.7 CiteScore
    9.7
  • SNIP value: 1.517 SNIP 1.517
  • IPP value: 5.61 IPP 5.61
  • SJR value: 2.601 SJR 2.601
  • Scimago H <br class='hide-on-tablet hide-on-mobile'>index value: 191 Scimago H
    index 191
  • h5-index value: 89 h5-index 89
Preprints
https://doi.org/10.5194/acp-2020-464
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-2020-464
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.

  27 Jul 2020

27 Jul 2020

Review status
This preprint is currently under review for the journal ACP.

Observations on aerosol optical properties and scavenging during cloud events

Antti Ruuskanen1, Sami Romakkaniemi1, Harri Kokkola1, Antti Arola1, Santtu Mikkonen2,3, Harri Portin1,a, Annele Virtanen2, Kari E. J. Lehtinen1,2, Mika Komppula1, and Ari Leskinen1,2 Antti Ruuskanen et al.
  • 1Finnish Meteorological Institute, P.O. Box 1627, 70211 Kuopio, Finland
  • 2Department of Applied Physics, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland
  • 3Department of Environmental and Biological Sciences, University of Eastern Finland, P.O. Box 1627, 70211 Kuopio, Finland
  • aHelsinki Region Environmental Services Authority, P.O. Box 100, 00066 HSY, Finland

Abstract. Long term statistics of atmospheric aerosol and especially cloud scavenging were studied at the Puijo measurement station in Kuopio, Finland, during October 2010–November 2014. Aerosol size distributions, scattering coefficients at three different wavelengths (450 nm, 550 nm, and 700 nm), and absorption coefficient at wavelength 637 nm were measured with a special inlet system to sample interstitial and total aerosol in clouds. On average, accumulation mode particle concentration was found to be temperature dependent with lowest average concentrations of 200 cm−3 around 0 °C increasing to more than 800 cm−3 for temperatures higher than 20 °C. From the in-cloud measurements, both scattering and absorbing material scavenging efficiencies were observed to have slightly increasing temperature dependence. At 0 °C the efficiencies of scattering and absorbing matter were 0.85 and 0.55 with slopes of 0.005 °C−1 and 0.003 °C−1, respectively. Additionally, scavenging efficiencies were studied as a function of the diameter at which half of the particles are activated into cloud droplets. This analysis indicated that the is a higher fraction of absorbing material, typically black carbon, in smaller sizes so that at least 20–30 % of interstitial particles within clouds consist of absorbing material. In addition, the PM1-inlet revealed that approximately 20 % of absorbing material was observed to reside in particles with ambient diameter larger than ~ 1 µm at relative humidity below 90 %. Similarly, 40 % of scattering material was seen to be in particles larger than 1 µm. Altogether, this dataset provides information on size dependent aerosol composition that can be applied in evaluating how well large-scale aerosol models reproduce aerosol composition, especially with respect to scavenging in stratus clouds.

Antti Ruuskanen et al.

Interactive discussion

Status: open (until 21 Sep 2020)
Status: open (until 21 Sep 2020)
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
[Subscribe to comment alert] Printer-friendly Version - Printer-friendly version Supplement - Supplement

Antti Ruuskanen et al.

Antti Ruuskanen et al.

Viewed

Total article views: 167 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
123 40 4 167 4 2
  • HTML: 123
  • PDF: 40
  • XML: 4
  • Total: 167
  • BibTeX: 4
  • EndNote: 2
Views and downloads (calculated since 27 Jul 2020)
Cumulative views and downloads (calculated since 27 Jul 2020)

Viewed (geographical distribution)

Total article views: 164 (including HTML, PDF, and XML) Thereof 164 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 

Cited

Saved

No saved metrics found.

Discussed

No discussed metrics found.
Latest update: 11 Aug 2020
Publications Copernicus
Download
Short summary
The study focuses mainly on cloud scavenging efficiency of absorbing particulate matter (mainly black carbon) but additionally covers cloud scavenging efficiency of scattering particles and statistics of cloud condensation nuclei. The main findings give insight how black carbon is distributed in different particle sizes and the sensitivity to get cloud scavenged. The main findings are useful for large scale modelling for evaluating cloud scavenging.
The study focuses mainly on cloud scavenging efficiency of absorbing particulate matter (mainly...
Citation