Wednesday, March 11, 2009

Global Warming Trends

When I commenced this blog two years ago, global warming had been with us for at least a decade and perhaps realistically for twenty years. It was indisputably warmer but is had also stabilized near the top end of the natural range as demonstrated in the historical record.

Also it was a matter of creditable measurement that the CO2 content of the atmosphere was very slowly increasing over the past century or two and this was clearly linked to our combustion of the fossil fuel inventory. No one could reasonably dispute the direct correlation and no one has. Very clearly, Mother Nature is slow at sponging up the surplus and it may also be true that higher levels are welcome. Theory has suggested that absorption will increase more rapidly as the percentage increases, so it is not linear.

Theorists then connected the dots and proclaimed the hypothesis that CO2 increase was forcing the climate change. The press was sold on the veracity of the theory and it became part of popular scientific belief. This belief system has since struggled to hold its own in the face of an unfortunate and sharp reversal in apparent climate ending the very nice twenty year trend line.

We have had two classic cold winters in a row and there is little reason to expect a reversal. In fact the present trend is negative and could possibly stay on the cold side of the historic range. Quite simply, facts in the field have demolished the trend line that supported the received fact of ongoing global warming. It simply ceased to be a fact.

In the meantime the sunspot theorists have been largely on the right side of the global warming curve and recent comments suggest that cycle 23 may have bottomed late last fall and we are about to enter an upswing there with concomitant rise in the global temperature. Again, we must wait and see.

Were I have taken issue is that the best projected impact of any CO2 forcing is totally within the real temperature range of the Holocene climate norm and we cannot properly predict and account for all the variables that contribute to that. This means that accepting any conclusion regarding CO2 forcing is both premature and most probably wrong to boot, while we cannot prove otherwise. This is true for both the pro and con position, but the balance of probabilities weigh against the pro position, now so popularized.

Importantly, CO2 forcing is not linear and is increasingly resisted by Mother Nature. All that means though is that the proper public policy is to ignore the weather and concentrate on the step by step removal of fossil fuels from the energy regime.

And that returns me to my original objective. The removal of CO2 must be done in conjunction with an ongoing reform and redesign of the operation of global agriculture. We have come a long way in understanding how that might be done.

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