Preprints
https://doi.org/10.5194/acpd-14-23309-2014
https://doi.org/10.5194/acpd-14-23309-2014

  10 Sep 2014

10 Sep 2014

Review status: this preprint was under review for the journal ACP but the revision was not accepted.

Meridional distribution of aerosol optical thickness over the tropical Atlantic Ocean

P. Kishcha1, A. M. da Silva2, B. Starobinets1, C. N. Long3, O. Kalashnikova4, and P. Alpert1 P. Kishcha et al.
  • 1Department of Geosciences, Tel-Aviv University, Tel-Aviv, Israel
  • 2Global Modeling and Assimilation Office, NASA/GSFC, Greenbelt, Maryland USA
  • 3Pacific Northwest National Laboratory, Richland, Washington, USA
  • 4Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA

Abstract. Previous studies showed that, over the global ocean, there is hemispheric asymmetry in aerosols and no noticeable asymmetry in cloud fraction (CF). In the current study, we focus on the tropical Atlantic (30° N–30° S) which is characterized by significant amounts of Saharan dust dominating other aerosol species over the North Atlantic. Over a limited area such as the tropical Atlantic, our study showed that strong meridional asymmetry in dust aerosols was accompanied by meridional CF asymmetry, by contrast to the global ocean. During the 10 yr study period (July 2002–June 2012), NASA Aerosol Reanalysis (aka MERRAero) showed that, when the meridional asymmetry in dust aerosol optical thickness (AOT) was the most pronounced (particularly in July), dust AOT averaged separately over the tropical North Atlantic was one order of magnitude higher than dust AOT averaged over the tropical South Atlantic. In the presence of such strong meridional asymmetry in dust AOT in July, CF averaged separately over the tropical North Atlantic exceeded CF averaged over the tropical South Atlantic by 20%. In July, along the Saharan Air Layer, Moderate Resolution Imaging Spectroradiometer (MODIS) CF data showed significant cloud cover (up to 0.8–0.9), which contributed to above-mentioned meridional CF asymmetry. Both Multi-Angle Imaging SpectroRadiometer (MISR) measurements and MERRAero data were in agreement on seasonal variations in meridional aerosol asymmetry. Meridional asymmetry in total AOT over the Atlantic was the most pronounced between March and July, when dust presence over the North Atlantic was maximal. In September and October, there was no noticeable meridional asymmetry in total AOT over the tropical Atlantic.

P. Kishcha et al.

 
Status: closed
Status: closed
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
Printer-friendly Version - Printer-friendly version Supplement - Supplement
 
Status: closed
Status: closed
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
Printer-friendly Version - Printer-friendly version Supplement - Supplement

P. Kishcha et al.

P. Kishcha et al.

Viewed

Total article views: 1,825 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
1,292 450 83 1,825 70 71
  • HTML: 1,292
  • PDF: 450
  • XML: 83
  • Total: 1,825
  • BibTeX: 70
  • EndNote: 71
Views and downloads (calculated since 10 Sep 2014)
Cumulative views and downloads (calculated since 10 Sep 2014)

Cited

Saved

Latest update: 02 Dec 2021
Download
Altmetrics