Preprints
https://doi.org/10.5194/acp-2021-1071
https://doi.org/10.5194/acp-2021-1071
 
16 Feb 2022
16 Feb 2022
Status: this preprint was under review for the journal ACP. A revision for further review has not been submitted.

Vertical aerosol particle exchange in the marine boundary layer estimated from helicopter-borne measurements in the Azores region

Janine Lückerath1,a, Andreas Held2,a, Holger Siebert1, Michel Michalkow1, and Birgit Wehner1 Janine Lückerath et al.
  • 1Leibniz Institute for Tropospheric Research, Leipzig, Germany
  • 2Environmental Chemistry and Air Research, Technische Universität Berlin, Germany
  • apreviously at: Atmospheric Chemistry, University of Bayreuth, Germany

Abstract. Aerosol particles are important for radiation effects, cloud formation, and therefore, the climate system. A detailed understanding of the spatial distribution of aerosol particles within the atmospheric boundary layer, which depends on sources and sinks as well as long-range transport and vertical exchange, is important. Especially in marine regions, where the climate effect of clouds is comparable high, long-range transport with subsequent vertical mixing is dominating over local aerosol sources.

In this study, three different methods were applied to estimate the vertical aerosol particle flux in the marine boundary layer (MBL) and the vertical exchange between the MBL and the free troposphere (FT): Eddy covariance (EC), flux-gradient similarity (K-theory), and the mixed layer gradient method (MLG). For the first time, MBL aerosol fluxes derived from these three methods were compared in the framework of the "Azores stratoCumulus measurements Of Radiation, turbulEnce and aeroSols" (ACORES) field campaign in the Azores region in the North-East Atlantic Ocean in July 2017. Meteorological parameters as well as aerosol and cloud properties were measured in the marine troposphere using the helicopter-borne measurement platform ACTOS (Airborne Cloud Turbulence Observation System).

All three methods were applied to estimate the net particle exchange between MBL and FT. In many cases, the entrainment fluxes of the MLG method agreed within the range of uncertainty with the EC and K-theory flux estimates close to the top of the MBL, while the surface flux estimates of the different methods diverged. It was not possible to measure directly above the surface with the helicopter-borne payload, which might be a source of uncertainty in the surface fluxes. The observed particle fluxes at the top of the MBL ranged from 0 to 10 · 106 m−2 s−1 both in the upward and the downward direction, and the associated uncertainties were on the same order of magnitude. Even though the uncertainties of all three methods are considerable, the results of this study contribute to an improved understanding of the transport of particles between the MBL and FT, and their distribution in the MBL.

Janine Lückerath et al.

Status: closed (peer review stopped)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on acp-2021-1071', Anonymous Referee #1, 11 Mar 2022
  • RC2: 'Comment on acp-2021-1071', Anonymous Referee #3, 01 Apr 2022
  • RC3: 'Comment on acp-2021-1071', Anonymous Referee #2, 04 Apr 2022

Status: closed (peer review stopped)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on acp-2021-1071', Anonymous Referee #1, 11 Mar 2022
  • RC2: 'Comment on acp-2021-1071', Anonymous Referee #3, 01 Apr 2022
  • RC3: 'Comment on acp-2021-1071', Anonymous Referee #2, 04 Apr 2022

Janine Lückerath et al.

Janine Lückerath et al.

Viewed

Total article views: 234 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
178 41 15 234 7 8
  • HTML: 178
  • PDF: 41
  • XML: 15
  • Total: 234
  • BibTeX: 7
  • EndNote: 8
Views and downloads (calculated since 16 Feb 2022)
Cumulative views and downloads (calculated since 16 Feb 2022)

Viewed (geographical distribution)

Total article views: 312 (including HTML, PDF, and XML) Thereof 312 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Latest update: 27 May 2022
Download
Short summary
Three different methods were applied to estimate the vertical aerosol particle flux in the marine boundary layer (MBL) and between MBL and free troposphere. For the first time, aerosol fluxes derived from these three methods were estimated and compared using airborne aerosol measurements using data from the ACORES field campaign in the North-East Atlantic Ocean in July 2017. The amounts of fluxes were small and directed up and downwards for different cases, but the methods were applicable.
Altmetrics