Wonder why the whole central band of Africa is just covered in fires, households? deforestation?
I did a private pilot license in Africa, the biggest "plus" was that I always knew the direction of the wind on the ground by looking at all these fires. There was never a time when I didn't see smoke unless I was flying in very remote areas.
Heating isn't really an issue in the part I lived (warm all year round, even in the night) and the smell of burned plastic is quite distinguishable, even at higher altitudes.
Additionally, in a rainforest, wood is a cheap and easily available source of fuel for day to day household energy needs in areas that are rural, remote and with no electrical services.