Wildfires prevent Global Warming?

Question

Somewhere I heard that the theory that the particulate matter of wildfires can prevent global warming. I cant find any info on it now. Any info appreciated.

Answer 1

Dana1981 gives a good answer.

By their very nature wildfires burn tracts of trees, scrub, brush etc all of which are plants.

Plants grow via photosynthesis, part of the process sequesters carbon dioixide such that about two thirds of the dry mass of plant material is carbon. One mature tree acts as a storehouse for 2 to 3 tons of carbon. Burn the tree (and any other biomass) and much of the carbon oxidises into carbon dioxide.

The particulate matter from the fires disperse, the heavier particles quickly falling to earth but the ligher ones remaining suspended in the atmosphere where they block out some sunlight. These particles aren't particularly reflective so they don't reflect the sunlight back into space, they stop it in it's tracks by absorbing the solar radiation. Ultimately this is released as thermal radiation when the ambient temperature falls. Thermal radiation is the type that is retained within the atmosphere by greenhouse gases. If the particulate matter is dispersed into the upper atmosphere it will contribute little to global warming, at lower altitudes it has a greater contribution.

So in short what we have is particulate matter both blocking sunlight but at the same time contributing to global warming. Dispersed equally throughout the atmosphere the two would be more or less in equilibrium. Although this part of the equation is balanced there's the matter of all that CO2 which was released.

The net effect is a positive contribution to global warming.

Answer 2

Certainly not on the long run. In the short term it's possible that the particles emitted by the fire will block sufficient sunlight to cause a very short-term cooling effect. However, that will soon be overwhelmed by the loss of CO2-absorbing trees as well as the emission of the CO2 which the trees had been storing.

Deforestation is the single largest contributor to anthropogenic global warming:

http://cait.wri.org/figures.php?page=World-FlowChart&view=100

Answer 3

I agree with Dana1981's answer. The overall effect would be negative, even if a short-term positive result is found.

Answer 4

Thats not true!All fires affect the ozone layer!Global warming only gets worse from wildfires!