I find it fascinating that many have reached a conclusion the human species is polluting the earth and fouling the air with CO2 plus other noxious gases. These concerns have resulted in various theories and plans to correct the problem.
Not all that long ago there was a proposal (covered by the Fresno Bee) that dairy cows were passing volumes of methane gas into the atmosphere. It was suggested these herds should be reduced. It is understood that while the offending herds are passing gas, literally hundreds of cars are passing by discharging unknown quantities of pollutants into the air.
Politicians have proposed various tax solutions including an incredible "Cap and Trade" scheme to exact taxes from huge corporations which are passed on to the consumer. And now many are suggesting we need a "back-up" plan in case all these brilliant plans, including "geo-engineering," might not work.
I hasten to add that, as a back-up plan, we might consider reducing the human population. There was a time, many years ago, when massive forests existed on the face of the earth including the rain forests of Africa and South America which scrubbed the air of CO2. Of course, in those days the population was measured in the millions (not billions) and there was no need to cut down trees to provide land for food and living space.
I am reminded of that infamous poster picturing a land mass completely covered by humans standing shoulder to shoulder and restricted only by the world's oceans.
Possibly, one might recall the movie "Soylent Green" starring Charlton Heston and Edward G Robinson. This movie pictured a disturbing view of a future society plagued with over-population and life threatening pollution. The frightening solution to hunger in this future world was feeding the masses with recycled humans.
All I'm saying is that, as long as these smart intellectuals are considering backup plans, why not take a long look at over-population.