how were the forests formed at first? how does global warming become a major disaster for the earth?
Initially the formation of photosynthetic bacteria occurred and then by a gradual process of evolution a number of trees and forests came into existence.
Global warming is expected to cause climate change on the earth which would lead to extinction of various species as fast changing climate would not let plants and animals to adapt and would ultimately prove catastrophic for earth. Global warming would also lead to the submerging of various small islands into sea as water level would rise.