Climate Dynamics

, Volume 46, Issue 1, pp 585–599

Interannual modulation of subtropical Atlantic boreal summer dust variability by ENSO

  • Michael J. DeFlorio
  • Ian D. Goodwin
  • Daniel R. Cayan
  • Arthur J. Miller
  • Steven J. Ghan
  • David W. Pierce
  • Lynn M. Russell
  • Balwinder Singh
Article

DOI: 10.1007/s00382-015-2600-7

Cite this article as:
DeFlorio, M.J., Goodwin, I.D., Cayan, D.R. et al. Clim Dyn (2016) 46: 585. doi:10.1007/s00382-015-2600-7

Abstract

Dust variability in the climate system has been studied for several decades, yet there remains an incomplete understanding of the dynamical mechanisms controlling interannual and decadal variations in dust transport. The sparseness of multi-year observational datasets has limited our understanding of the relationship between climate variations and atmospheric dust. We use available in situ and satellite observations of dust and a century-length fully coupled Community Earth System Model (CESM) simulation to show that the El Niño-Southern Oscillation (ENSO) exerts a control on North African dust transport during boreal summer. In CESM, this relationship is stronger over the dusty tropical North Atlantic than near Barbados, one of the few sites having a multi-decadal observed record. During strong La Niña summers in CESM, a statistically significant increase in lower tropospheric easterly wind is associated with an increase in North African dust transport over the Atlantic. Barbados dust and Pacific SST variability are only weakly correlated in both observations and CESM, suggesting that other processes are controlling the cross-basin variability of dust. We also use our CESM simulation to show that the relationship between downstream North African dust transport and ENSO fluctuates on multidecadal timescales and is associated with a phase shift in the North Atlantic Oscillation. Our findings indicate that existing observations of dust over the tropical North Atlantic are not extensive enough to completely describe the variability of dust and dust transport, and demonstrate the importance of global models to supplement and interpret observational records.

Keywords

Dust ENSO NAO CESM Teleconnections Decadal variability 

Supplementary material

382_2015_2600_MOESM1_ESM.docx (2.1 mb)
Supplementary material 1 (DOCX 2158 kb)

Copyright information

© Springer-Verlag Berlin Heidelberg 2015

Authors and Affiliations

  • Michael J. DeFlorio
    • 1
  • Ian D. Goodwin
    • 2
  • Daniel R. Cayan
    • 1
    • 3
  • Arthur J. Miller
    • 1
  • Steven J. Ghan
    • 4
  • David W. Pierce
    • 1
  • Lynn M. Russell
    • 1
  • Balwinder Singh
    • 4
  1. 1.Climate, Atmospheric Science, and Physical Oceanography, Scripps Institution of OceanographyUniversity of California, San DiegoLa JollaUSA
  2. 2.Department of Environmental SciencesMacquarie UniversityNorth RydeAustralia
  3. 3.U.S. Geological SurveyLa JollaUSA
  4. 4.Pacific Northwest National LaboratoryRichlandUSA