Journal cover Journal topic
Geoscientific Model Development An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

IF value: 5.240
IF5.240
IF 5-year value: 5.768
IF 5-year
5.768
CiteScore value: 8.9
CiteScore
8.9
SNIP value: 1.713
SNIP1.713
IPP value: 5.53
IPP5.53
SJR value: 3.18
SJR3.18
Scimago H <br class='widget-line-break'>index value: 71
Scimago H
index
71
h5-index value: 51
h5-index51
Preprints
https://doi.org/10.5194/gmd-2020-163
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/gmd-2020-163
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.

Submitted as: model evaluation paper 08 Jun 2020

Submitted as: model evaluation paper | 08 Jun 2020

Review status
A revised version of this preprint is currently under review for the journal GMD.

Sensitivity of spatial aerosol particle distributions to the boundary conditions in the PALM model system 6.0

Mona Kurppa1, Pontus Roldin2, Jani Strömberg1, Anna Balling1, Sasu Karttunen1, Heino Kuuluvainen3, Jarkko V. Niemi4, Liisa Pirjola5, Topi Rönkkö3, Hilkka Timonen6, Antti Hellsten6, and Leena Järvi1,7 Mona Kurppa et al.
  • 1Institute for Atmospheric and Earth System Research, Faculty of Science, University of Helsinki, Helsinki
  • 2Division of Nuclear Physics, Lund University, Lund, Sweden
  • 3Aerosol Physics Laboratory, Physics Unit, Tampere University, Tampere, Finland
  • 4Helsinki Region Environmental Services Authority (HSY), Helsinki, Finland
  • 5Department of Automotive and Mechanical Engineering, Metropolia University of Applied Sciences, Vantaa, Finland
  • 6Atmospheric Composition Research, Finnish Meteorological Institute, Helsinki, Finland
  • 7Helsinki Institute of Sustainability Science, University of Helsinki, Helsinki

Abstract. High-resolution modelling is needed to understand urban air quality and pollutant dispersion in detail. Recently, the PALM model system 6.0, which is based on the large-eddy simulation (LES), was extended with a detailed aerosol module SALSA2.0 to enable studying the complex interactions between the turbulent flow field and aerosol dynamic processes. This study represents an extensive evaluation of the modelling system against the horizontal and vertical distributions of aerosol particles measured using a mobile laboratory and a drone in an urban neighbourhood in Helsinki, Finland. Specific emphasis is on the model sensitivity of aerosol particle concentrations, size distributions and chemical compositions to boundary conditions of meteorological variables and aerosol background concentrations. The meteorological boundary conditions are drawn from both a numerical weather prediction model and observations, which occasionally differ strongly. Yet, the model shows good agreement with measurements (fractional bias < 0.67, normalised mean-square error < 6, factor of two > 0.3, normalised mean bias factor < 0.25 and normalised mean absolute error factor < 0.35) in respect of both horizontal and vertical distribution of aerosol particles, their size distribution and chemical composition. The horizontal distribution is most sensitive to the wind speed and atmospheric stratification and vertical distribution to the wind direction. The aerosol number size distribution is mainly governed by the flow field along the main street with high traffic rates and in its surroundings by the background concentrations. The results emphasize the importance of correct meteorological and aerosol background boundary conditions, in addition to accurate emission estimates and detailed model physics, in quantitative high-resolution air pollution modelling and future urban LES studies.

Mona Kurppa et al.

Interactive discussion

Status: final response (author comments only)
Status: final response (author comments only)
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
[Login for Authors/Topical Editors] [Subscribe to comment alert] Printer-friendly Version - Printer-friendly version Supplement - Supplement

Mona Kurppa et al.

Data sets

Mobile and stationary air pollution measurements around an air quality monitoring site on Mäkelänkatu in Helsinki, Finland M. Kurppa, A. Balling, S. Karttunen, H. Kuuluvainen, L. Järvi, J. Niemi, L. Pirjola, T. Rönkkö, and H. Timonen https://doi.org/10.5281/zenodo.3828508

Model input and output, performance measures and modifications in the source code for PALM simulations on Mäkelänkatu in Helsinki, Finland M. Kurppa https://doi.org/10.5281/zenodo.3824351

Input files and scripts for creating PALM simulation input files on Mäkelänkatu in Helsinki, Finland M. Kurppa and J. Strömberg https://doi.org/10.5281/zenodo.3839684

Model code and software

Python scripts for evaluating PALM simulations against mobile air quality observations on Mäkelänkatu in Helsinki, Finland M. Kurppa https://doi.org/10.5281/zenodo.3839462

Mona Kurppa et al.

Viewed

Total article views: 551 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
347 167 37 551 33 26 28
  • HTML: 347
  • PDF: 167
  • XML: 37
  • Total: 551
  • Supplement: 33
  • BibTeX: 26
  • EndNote: 28
Views and downloads (calculated since 08 Jun 2020)
Cumulative views and downloads (calculated since 08 Jun 2020)

Viewed (geographical distribution)

Total article views: 425 (including HTML, PDF, and XML) Thereof 425 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: 22 Sep 2020
Publications Copernicus
Download
Short summary
High-resolution modelling is needed to solve the aerosol concentrations in a complex urban area. Here the performance of an aerosol module within the PALM model to simulate the detailed horizontal and vertical distribution of aerosol particles is studies. Further, sensitivity to the meteorological and aerosol boundary conditions is assessed using both model and observation data. The horizontal distribution is sensitive to the wind speed and stability, and vertical to the wind direction.
High-resolution modelling is needed to solve the aerosol concentrations in a complex urban area....
Citation