Greeenpeace has created many "advertisements" to raise awareness for the environment. In this illustration it shows a man cutting down a tree, in addition the tree is in the shape of a nuclear explosion. They are trying to send a message that deforestation is as destructive as the catastrophe in Hiroshima and Nagasaki (1945-atomic bombings).

http://blog.humanityy.com/en/greenpeace-ads