warming before it's too late. Thirdly, if and when the energy crisis is somehow solved, the need for clean water would still exist, especially in Africa. Without water there can be no life on Earth, it is as simple as that. allen white, Pennsylvania "" #1 Challenge: The definitive answer lies with providing huge incentives for "capping" and decreasing human population AND converting totally away from the usage of all fossil material immediately. It is the economic mentality of always developing- : "More"; "Bigger"; "Faster" at an ever increasingly, exponential rate that has gotten us into this "FIX". And the atmospheric carbon issue is just one of the related, lethal threats against all life on this planet. Take a good look at "Endocrine/ DNA mutation" from long chain (carbons) and GLOBAL SEWAGE. If we don't spend all of our energy, talent and intelligence on this problem now, life on this planet won't be around long enough to be affected by the results of global warming. #2 and final Challenge: "Solar Energy" Enough solar energy strikes the surface of the earth every 24 hours to "power the world for a year. The math is easy. "Keywords": (2) #1"Sustainability"- (Within earth's renewable systems only). #2"Population Control"- Strict, incentive based control, flat growth/ replacement only. Plus the "gloom & doom" is and always will be a reality as long as contrived, inordinate material wealth and insatiable greed prevails within the human species. The Human will never get it "Right" until he has the