The Mountain Pine Beetle as positive feedback loop

Twenty years ago in British Columbia, two facts were well understood and widely known in the scientific community:

  1. The population of the Mountain Pine Beetle (MPB) was being kept in check by the die-off due to the coldest winter temperatures.
  2. Winter temperatures were rising due to the increasing level of atmospheric carbon dioxide.

Was there no one person who noticed that these two established facts, when taken together, spelled disaster for BC’s lodgepole pine forests? If there was, did they not speak up and try to sound a warning? If they did, why was that warning not heeded and why did it never make it into public awareness?

There would seem to be only three possibilities that would answer the above questions, criminal negligence, or unbelievable stupidity would have to have taken place in the scientific community or the governing bodies to which they answered, or one or other of these bodies would have been corrupted by bribes by an outside party or parties.MPB damage in British Columbia
Scientists are not known for being negligent or stupid and only in rare cases corruptible, same for the govenors of universities. This leaves private corporations and government departments who employ scientists as the most likely places for the supression of impending disaster to have taken place. Take your pick — increasingly in recent years, governments have been shown to be emminently corruptible and the sources of such corruption have been shown to be private corporations.

For those who still think that Global warming is a new and unproven idea, the concept first entered the scientific literature in 1824 when French physicist Joseph Fourier postulated the “greenhouse effect”. By the 1850’s, Irish physicist John Tyndall had come up with a way to actually test and measure the effect and by 1858 had effectively proven Fourier’s theory. At the end of the 19th century, Swedish chemist Svante Arrhenius estimated that a doubling of atmospheric carbon dioxide would increase Earth’s temperature by 3.8 degrees Fahrenheit, a figure within the IPCC’s estimate of 3.6 to 8.1 degrees Fahrenheit for a doubling of CO2 from 19th century levels — stop protesting the truth and do some reading.

So we come to the Positive Feedback Loop aspect of the MPB wintering through, it goes like this:

  • Excess CO2 from various sources, notably the burning of fossil fuels, enters the atmosphere and increases the insulating blanket of the greenhouse effect
  • In areas where conditions are right, pine trees grow and utilize CO2 from the air for that growth. This immobilizes or sequesters the carbon in the structure of the trees and, if conditions remain stable, the system will reach eqilibrium.
  • As increasing amounts of greenhouse gases are emitted beyond the growth of the trees’ (or other ecological services) ability to sequester, the atmosphere warms up and minimum winter temperatures increase above the level required to keep the MPB population under control
  • MPB attack and kill vast swaths of pine trees across areas previously under the control of cooler temperatures
  • After a period of a few years, most of the dead pine falls and begins to break down. This breakdown (rotting or increase of entropy) of the wood releases greenhouse gases such as CO2 – carbon dioxide, and CH4 – methane to enter the atmosphere and reinforce the greenhouse effect

So the loop is that emission of greenhouse gases eventually causes the breakdown of wood structure, which causes an increase in the emission of greenhouse gases. This is known as a POSITIVE feedback look because the cause is reinforced by the effect, not because the result is necessarily positive from a human point of view.

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