Possible Clues:

• Closed system that includes all life on Earth
• Place that could support life peer — chose differently
• Planet's livable zone
• Copse managed at this point where it's easy to breathe
• Global system copes with unusual occurrence here?
• Region of planet where life exists
• Core sheep (anag.)
• A region in which life exists or could exist
• Eastern firm starts to sell products in this place where living is possible
• Earth's habitable parts