im scare2

http://www.universetoday.com/2007/07/25/the-end-of-everything/

The End of Everything - 10100 years and beyond
When the last black hole evaporates, all that will remain in the Universe are photons of radiation, and elementary particles that escaped capture by black holes. The temperature of the entire Universe will reach a final temperature just above absolute zero

>>10
I think that is the case because by the time we are actually in danger of not having enough oxygen in the atmosphere to respire, we will almost certainly have developed some sort of mass conversion system from CO2 to O2.