this scientist told me, and I thought his 
characterization of this problem was one of the most sort of 
commonsense ones I have heard, he said we are now engaged in the 
largest experiment in human history, and we are the guinea pigs. And he 
meant by that that this whole global warming experiment that we are 
conducting in the world, we are the ones likely to be affected by it in 
ways we cannot fully predict.
  In other words, we cannot fully predict the year we will not be able 
to grow wheat in the sou