The dust load and radiative impact associated with the June 2020 historical Saharan dust storm

Diana Francis (1) , Narendra Nelli (1) , Ricardo Fonseca (1) , Michael Weston (1) , Cyrille Flamant (2) , Charfeddine Cherif (1)

1 ENGEOS Lab - Environmental and Geophysical Sciences Lab
2 TROPO - LATMOS

In June 2020, a major dust outbreak occurred in the Sahara that impacted the tropical Atlantic Ocean. In this study, the dust load and radiative forcing of the dust plumes on both the atmosphere and ocean surface is investigated by means of observations and modelling. We estimated dust loadings in excess of 8 Tg over the eastern tropical Atlantic, comparable to those observed over the desert during major Saharan dust storms. The dust induced an up to 1.1 K net warming of the ocean surface and a 1.8K warming of the air temperature (i.e., two to three times the respective climatological standard deviations), with a +14 W m⁻² (∼28% of the mean value) increase in the surface net radiation flux at night. As the dust plumes extended all the way to the Caribbean, it is possible that this historical dust event helped fuel the record-breaking 2020 Atlantic hurricane season.

Mots clés: Dust aerosols; Radiative forcing; Sahara; Tropical Atlantic; WRF-Chem

Domaines: Physique Atmosphérique et Océanique [physics.ao-ph]

Diana Francis, Narendra Nelli, Ricardo Fonseca, Michael Weston, Cyrille Flamant, et al.. The dust load and radiative impact associated with the June 2020 historical Saharan dust storm. Atmospheric Environment, 2022, 268, pp.118808. ⟨10.1016/j.atmosenv.2021.118808⟩. ⟨insu-03402562v2⟩