Answer:
The investigation of past atmospheric compositions and past climate will help us understand the extent to which the use of fossil fuel has, and is still altering the atmosphere. These investigations will shed light on how much damage or good (if any) these fossil fuel usage is doing to the atmosphere and then we may from these investigations, put regulations, or total ban on some of these fossil fuels (if not ban their usage completely) in an effort to return the atmosphere back to its healthy composition, and proportion of useful elements.