West Africa is the largest source of dust on Earth. African dust is often transported by the atmospheric circulation westward into the tropical Atlantic Ocean. Meanwhile, there is substantial biomass burning smoke from the west coast of Africa also propagating into the tropical Atlantic Ocean. In consequence, the atmosphere in the tropical Atlantic Ocean is rich of aerosol that is unmatched by any other part in the world, making it an ideal natural laboratory to study the climatic impacts of aerosol.

One of my research projects is to explore possible climatic impacts of African aerosol on short-term (seasonal to decadal) climate variability of the west African monsoon and the Atlantic marine ITCZ (AMI) (in collaboration with Prof. Joseph Prospero of U Miami and Dr. Chien Wang of MIT). It is known that there are strong interactions between the AMI, sea surface temperature (SST) in the tropical Atlantic, and the West African monsoon. Effects of African aerosol on the AMI and monsoon rainfall may possibly fill the missing link in the tropical Atlantic-African climate system that involves interactions among the ITCZ, SST, land surface, rainfall and aerosol. My research is to explore whether such a link can be established using currently available satellite observations of aerosol and precipitation.

In order to thoroughly understand the climatic effects of aerosol, we much know well the 3-dimensional (3D) distribution and transport of aerosol. Using data from CALIPSO, a satellite providing information of vertical profiles of aerosol, we have started to put together the puzzles of the 3D structure of aerosol. The following figure shows an example of dust and smoke over the tropical Atlantic Ocean in boreal winter. It suggest different sources and pathways of aerosol transport. For more information on the 3D structure of African aerosol, go to the website of Aaron Adams, a graduate student working on satelliate diagnoses of Afrian aerosol who produced this figure.
3D distribution of African aerosol. Colors represent the number concentration of aerosol (including dust, smoke, and their mixture) detected by CALIPSO for boreal summer (2006-2008). Zonal, meridional, and vertical averages are projected onto left side, back, and base of primary figure (top). Slices are set to y-z view for structure analysis (bottom).

Recent publications and manuscripts resulted from this research include::

Huang, J., C. Zhang, and J. Prospero, 2009: African Dust Outbreaks: Temporal and Spatial Variability over the Tropical Atlantic Ocean. J. Geophy. Res., accepted. (manuscript).

Huang, H., A. Adams, C. Wang, C. Zhang, 2009: Aerosol and West African Monsoon Precipitation: Observations and Simulations. Annales Geophysicae, 27, 4171-4181. (reprint).

Huang, J., C. Zhang, and J. Prospero, 2009: African aerosol and large-scale precipitation variability in the West African Monsoon. Environmental Research Letters, 4, 015006 (8pp) doi: 10.1088/1748-9326/4/1/015006, (reprint).

Huang, J., C. Zhang, and J. Prospero, 2009: Aerosol-Induced Large-Scale Variability in Precipitation over the Tropical Atlantic. J. Clim, 22, 4970-4988. (reprint).

Huang, J., C. Zhang, and J. Prospero, 2009: Large-Scale Effect of Aerosol on Precipitation in the West African Monsoon Region. Quart. J. Roy. Met. Soc., 135, 581-594.(reprint)