Land that currently is not used for agriculture in places like Siberia and Canada may never be suitable for intensive cultivation. That is one of the problems that accompanies shifting biomes. It takes years before there is sufficient biomass on the ground for farming with any kind of reasonable yield. In Canada in particular the Canadian Shield is mostly barren rock with small pockets of very poor soils, suboptimal grey podzolic. So I don’t agree that automatically surpluses will be transferred from one area such as the tropics to more temperate climes in both the northern and southern hemispheres.

I do agree that the best answer to human induced climate change is to reduce human population but at the same time finding economical, renewable, marketable alternatives to coal and other CO2 producing forms of energy. That’s where countries and energy companies should be spending their dollars because there are too many questions that we have yet to answer about climate change consequences.

For the sake of discussion I will stipulate that human activity is entirely responsible for a global climate is 2-degrees warmer. That is to say the global climate has warmed as the hominid population has rapidly grown from well less than 2-billion to over 7-billion. See graph: http://en.wikipedia.org/wiki/File:World-Population-1800-2100.svg

Notice that in 1960 the world population curve adopted a 60° slope upwards, which continues without change right up to 2013. Should be obvious that major changes in population and moderate changes in climate require major changes in economic practice.

But climate and population can change more rapidly than political institutions and economic systems can change to optimize exploitation of the new conditions. More rain and longer growing seasons in Siberia and Canada allow more agricultural production there, while less rain in the tropics reduces agricultural production in the tropics. Conditions that might bring surplus to one region might bring famine to another. The fair question is whether you think it moral or wise to increase total global agricultural production by changing the climate so that the location of the production shifts from one region to another? To put the question another way, what is the optimum average global temperature? How could one answer that question without first answering: What is the optimum population level?

So while it seems likely global hominid population pressures are causing global warming, it seems unlikely anyone with serious political policy influence outside of China is going to stand up to honestly answer the three main questions, and then advocate the only possible measure that might reverse the warming trend: drastic population reduction. China now answers the three questions: “The optimum temperature is higher than it is now. It’s perfectly moral to increase total agricultural (and industrial) production regardless of economic displacements. The optimum hominid population is 1.3 Billion Chinese.” China is telling the world community, “We got our population under control, and now we are going to burn our fair share of coal.”

If the Western nations cannot give or show China and India a technology for power generation that is more economical than coal, they better prepare for ever-growing climate change displacements. Third world nations will just have to join the Devil in taking the hindmost.