Seasonality: The Central African Plume (CAP) exists from June to October each year at varying levels of intensity.
Sources Anthropogenic: The CAP is derived from biomass burning linked to land clearing and agriculture plus a gas flares in the oil production industry identified by the World Bank Global Gas Flaring Reduction Partnership and NOAA which extend from Angola to Gabon.
Sources Natural: Volcanoes along the African Rift Valley from Tanzania to Uganda contribute to the plume.
Trajectory: The CAP exits to the south east towards the southern ocean and west across the Atlantic Ocean towards Brazil.
Effects: I have yet to undertake research on this plume.