“Men argue; nature acts.” —Voltaire
 
Once again, we are confronted with disturbing evidence of a climate change feedback loop. Researchers have recently shown that the vast swath of pine trees killed by the Mountain Pine Beetle will decompose and release huge amounts of carbon dioxide into the air. The effect will be similar to doubling the number of planes, trains and automobiles in Canada over the next five years.
 
As troubling as this is, it does not begin to account for what might happen if these same beetles succeed in attacking the rest of the pine trees in Canada’s boreal forest. That’s where the feedback loop comes into play. With much more carbon dioxide in the atmosphere, we’ll have even less severe winters, and an even higher survival rate of the Mountain Pine Beetle. And more beetles will destroy more forests and more dead forests will release more CO2.
 
Feedback loops are extremely worrisome because they can accelerate like a runaway train. The increased output from one part of the cycle feeds into and increases another part of the cycle.
 
We have seen this with forest fires. Forest fires in Canada now account for the loss of three times the forest area per year as compared to that which occurred in the 1970’s. In a manner not totally dissimilar to the damage wrought by the Mountain Pine Beetle, huge amounts of carbon dioxide are lost to the atmosphere and contribute to global warming. The result is higher average temperatures, more prolonged droughts, and therefore more fires.
 
Another concern lies further north, beyond the boreal forest, where trees are scarce and the soil is like a giant sponge. The feedback effect which is occurring there relates to the loss of methane from the soil due to warmer temperatures. Methane is a much more effective greenhouse gas than carbon dioxide, and since the start of the industrial revolution, the concentration of methane in the atmosphere has doubled. What has scientists worried is that this loss of methane from the soil could accelerate in another feedback loop similar to those described above. And this is doubly worrisome, since we already know that the northern regions are warming to a much greater degree than the temperate regions to the south.
 
Travel further north still, and we encounter the Arctic Ocean where yet another feedback effect is contributing to the warming process. We have all heard that the ice is disappearing up there. Not only is the area of ice diminishing, but the thickness of the ice sheets is waning, also. One result is that polar bears are having trouble feeding themselves and their cubs due to the loss of the ice platforms that they use to hunt seals from.
 
However, the ice serves another vital function. It tends to reflect light back into space which would otherwise warm the planet. When the ice is lost, the darker oceans will absorb the solar radiation. The absorbed radiation heats the water and with the onset of winter, the ice has a much harder time forming. Less ice in the winter means more absorption of solar energy. The cycle continues unabated.
 
At some point, these feedback effects will take on a life of their own. Some of them may have already started to run out of control. We have started the process of cause and effect, but Mother Nature has the capacity to continue it on a much bigger scale. She has the capacity to transform the planet in a manner that could literally destroy civilization. It would serve us right, I suppose. We are not the most benign species and we will likely deserve whatever happens to us…though those who ride bicycles to work, grow vegetables in their backyards, and limit their family sizes will likely deserve it a lot less than the rest of us.