Journal cover Journal topic
Atmospheric Chemistry and Physics An interactive open-access journal of the European Geosciences Union
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
Research article
12 Jun 2017
Review status
This discussion paper is a preprint. A revision of this manuscript was accepted for the journal Atmospheric Chemistry and Physics (ACP) and is expected to appear here in due course.
Profiling of Saharan dust from the Caribbean to West Africa, Part 2: Shipborne lidar measurements versus forecasts
Albert Ansmann1, Franziska Rittmeister1, Ronny Engelmann1, Sara Basart2, Angela Benedetti3, Christos Spyrou4, Annett Skupin1, Holger Baars1, Patric Seifert1, Fabian Senf1, and Thomas Kanitz5 1Leibniz Institute for Tropospheric Research, Leipzig, Germany
2Barcelona Supercomputing Center, Dep. of Earth Sciences, Barcelona, Spain
3European Centre for Medium-Range Weather Forecasts, Reading, UK
4National and Kapodistrian University of Athens, Dep. of Physics, Athens, Greece
5ESTEC, Noordwijk, The Netherlands
Abstract. A unique 4-week ship cruise from Guadeloupe to Cabo Verde in April–May 2013 (see part 1, Rittmeister et al., 2017) is used for an in-depth comparison of dust profiles observed with a polarization/Raman lidar aboard the German research vessel Meteor over the remote tropical Atlantic and respective dust forecasts of a regional (SKIRON) and two global atmospheric (dust) transport models (NMMB/BSC-Dust, MACC/CAMS). New options of model-observation comparisons are presented. We analyze how well the modeled fine dust (submicrometer particles) and coarse dust contributions to light extinction and mass concentration match respective lidar observations, and to what extent models, adjusted to aerosol optical thickness observations, are able to reproduce the observed layering and mixing of dust and non-dust (mostly marine) aerosol components over the remote tropical Atlantic. Based on the coherent set of dust profiles at well defined distances from Africa (without any disturbance by anthropogenic aerosol sources over the ocean) we investigate how accurately the models handle dust removal at distances of 1500 km to more than 5000 km west of the Saharan dust source regions. It was found that (a) dust predictions are of acceptable quality for the first several days after dust emission up to 2000 km west of the African continent, (b) the removal of dust from the atmosphere is too strong for large transport paths in the global models, and (c) the simulated fine-to-coarse dust ratio (in terms of mass concentration and light extinction) is too high in the models compared to the observations. This deviation is already given close to the dust sources and then increases with distance from Africa.

Citation: Ansmann, A., Rittmeister, F., Engelmann, R., Basart, S., Benedetti, A., Spyrou, C., Skupin, A., Baars, H., Seifert, P., Senf, F., and Kanitz, T.: Profiling of Saharan dust from the Caribbean to West Africa, Part 2: Shipborne lidar measurements versus forecasts, Atmos. Chem. Phys. Discuss.,, in review, 2017.
Albert Ansmann et al.
Interactive discussionStatus: closed
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
Printer-friendly Version - Printer-friendly version      Supplement - Supplement
RC1: 'Review of Ansmann et al. for ACPD', Anonymous Referee #1, 02 Aug 2017 Printer-friendly Version 
RC2: 'Review of Ansmann et al, Profiling of Saharan dust from the Caribbean to West Africa', Anonymous Referee #2, 31 Aug 2017 Printer-friendly Version 
AC1: 'author's comments', Albert Ansmann, 31 Oct 2017 Printer-friendly Version Supplement 
Albert Ansmann et al.
Albert Ansmann et al.


Total article views: 442 (including HTML, PDF, and XML)

HTML PDF XML Total BibTeX EndNote
313 118 11 442 5 13

Views and downloads (calculated since 12 Jun 2017)

Cumulative views and downloads (calculated since 12 Jun 2017)

Viewed (geographical distribution)

Total article views: 442 (including HTML, PDF, and XML)

Thereof 441 with geography defined and 1 with unknown origin.

Country # Views %
  • 1



Latest update: 19 Nov 2017
Publications Copernicus