Ok. I read it. Maybe it would just be easier to move further north than to alter the human genome.

I don't think these people have really grasped what "climate change" really entails. It means a sudden (in geological terms) alteration in climate, not unlike the ones we are already familiar with, but compressed in time, so that it affects agricultural production through changes in rainfall patterns and ocean currents. etc over time scales on the order of a human lifetime or two instead of centuries. It would manifest itself as economic dislocation and political crisis, not global eco-catastrophe such as runaway greenhouse effects.

For example, the American Midwest could become a desert, and the Sahara the new Ukraine. Europe could become as cold as Labrador, and Siberia transform itself into the world's new wheat belt. A vast rain forest could swallow up Australia. These changes already have been known to occur naturally, the risk is that industrial activity and pollution could accelerate them so that political structures would not be able to adapt fast enough.

Eventually, the world ecosystem would stabilize at a new level of equilibrium, (it always has) perhaps one not too different overall than the one we have now. The world would not come to an end, but current cultural and political boundaries and population distributions would be incompatible with the new environmental regime.

Even if this is not what we see happening now (and something is definitely happening now, especially in the Arctic) we should be very conscious of these processes, studying them intensely, and coming up with realistic contingency plans and preventive measures. It's better to be safe than sorry, the risks are too high, and the corrections are easier and cheaper the sooner we begin.