Smoke got together with wet, foggy air and turned yellow. The smog often stayed over cities for sulphur dioxide = a poisonous gas that causes air pollution. surface =the top layer of something.
Answer: The manchineel, or poison guava tree, is so poisonous that smoke from its burning wood irritates the eyes, and latex from its leaves and bark causes skin inflammation. Its attractive, single or paired yellow-to-reddish, sweet-scented, applelike fruits have poisoned Spanish conquistadores, shipwrecked sailors, and present-day tourists visiting the Caribbean and Gulf of Mexico.