Some Major Feedbacks

Here are a few of the major feedbacks to our climate:

  1. Water Vapor The more carbon dioxide you add to the atmosphere, the more its effects (in terms of the absorbtion of radiation) will be amplified by the evaporation of water leading to greater water vapor.
  2. Albedo Effect The higher the temperatures go, the greater the loss of ice, glaciers, sea ice, and the lower the albedo over the ocean and the soil in the arctic regions.
  3. Permafrost Higher temperatures also mean that permafrost will melt, releasing methane as the result of organic decay. Methane is about 21X more powerful than carbon dioxide, but it tends to degrade into carbon dioxide after 40 years.
  4. Shallow Water Methane Hydrates There is also the greater likelihood of shallow water methane hydrates melting, releasing methane from their icy matrix.
  5. Reduced CO2 Uptake by Plants The higher the temperatures, the more soil will dry out in the temperate regions, leading to drought stress in plants combined with the heat stress which means that they will absorb less carbon dioxide.
  6. Reduced CO2 Uptake by the Ocean The higher the temperatures in the polar regions, the less carbon dioxide will be absorbed by the oceans until at some point it won't even be able to hold the carbon dioxide which it already has and it will become a net emitter.
  7. Destruction of Ozone The higher the rate of evaporation the greater the water vapor in the atmosphere leading to water vapor destroying ozone in the stratosphere, cooling of the stratosphere, the creation of a temperature differential between the lower and the upper, leading to increased winds near the surface, more upwelling of organic material from below, and the release of methane, some of which will result in further warming of the lower atmosphere.
  8. Poleward Ocean Flow As the ability of the climate system to radiate away thermal energy is reduced, to the extent that this takes place at lower latitudes it results in an increase in the poleward atmospheric and oceanic convection, meaning the higher latitudes will warm more rapidly, resulting in further ice loss, a lower albedo, and the more sunlight will be absorbed at the surface.

The problem is that all of these feedbacks are either feeding into one another, or beginning to kick in so that in time they will be feeding into one another. And the longer they go on, the less they will be driven by our actions and the more the whole process will begin to take on a life of its own. The big "tipping-points" are the loss of Arctic sea ice, the large scale loss of glaciers in Greenland, the large scale loss of glaciers in the Western Antarctic Peninsula - and as both Greenland and the Western Antarctic Peninsula will raise the sea level considerably, there will be positive feedback between the two.

But the biggest uncertainty in the whole equation is human action. Then again, the further we postpone action, the more we will be locked into current technologies with high carbon emissions and a higher population generating those emissions - partly as a result of industrial development in China and parts of the third world. One degree will probably be enough to set up positive feedback between Greenland and the Antarctic, but the higher the temperature the earlier the feedback will take place and the more chaotic it will be.

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