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The Yosemite Inferno In the Context of Forest Policy, Ecology and Climate Change
Lasrick writes "Andrew Revkin at DotEarthblog posts an assessment of the drivers of wildfire trends in the American West. He shows a graph of fire activity for the past 400 years in the Yosemite-Mariposa area, and a rather surreal time-lapse video of the current Rim Fire now burning in and around Yosemite."
http://dotearth.blogs.nytimes.com/2013/08/29/the-yosemite-rim-fire-in-the-context-of-forest-policy-ecology-and-climate-change/
Just in case anyone wants to actually, you know, read the article rather than being taken to a login screen.
The correlation between ignorance of statistics and using "correlation is not causation" as an argument is close to 1.
It's a combination of factors, of which warming is one. Probably the best summation from TFA:
"When you look at the long record, you see fire and climate moving together over decades, over centuries, over thousands of years," said pyrogeographer Jennifer Marlon of Yale University, who earlier this year co-authored a study of long-term fire patterns in the American West.
"Then, when you look at the last century, you see the climate getting warmer and drier, but until the last couple decades the amount of fire was really low. We've pushed fire in the opposite direction you'd expect from climate," Marlon said.
The fire debt is finally coming due.
This is pretty much what you'd expect. Leaving aside the question of the human contribution to warming and what we can do about it, the fact of global warming is established to all but the shrieking denialists; it's also a fact that under normal circumstances, ecosystems adapt to any change in climate--sometimes better than others, but they do adapt. Our fire suppression policies for the last century or so have prevented what would have been the normal adaptation from taking place. So now we're getting it all at once.
The correlation between ignorance of statistics and using "correlation is not causation" as an argument is close to 1.
Trees, over their life span, may sequester carbon. But forests do not. They are carbon neutral.
This is true over the very long term--in the extreme case of Carboniferous forests, 300 million years or so; we're only now getting around to releasing their carbon back into the atmosphere by burning coal. Obviously in most cases dead trees rot and release their carbon faster than that, but "fast" is relative, and it's still a very slow process by human standards. And most of the carbon from a dead tree doesn't go straight back into the atmosphere; it's taken up by other organisms, and ultimately goes back into the soil as part of the organic waste that makes forest floors into fertile ground for the next generation of trees. Rotted wood, bits of smaller plants, bug poop ... it all looks like a buffet to a sapling.
The correlation between ignorance of statistics and using "correlation is not causation" as an argument is close to 1.
Parent post is using some very incorrect assumptions.
Rotting vegetation does not release all the carbon that was sequestered during growth into the atmosphere. Much of it is transformed into other living things: termites and other insects, nematodes, fungus, etc. A log in contact with dirt becomes more soil; it does not evaporate into gases. The carbon is sequestered for as long as the ecosystem remains healthy and growing.
In a forest fire, a large amount of CO2 is released, but also a large amount remains in unburned wood (especially in the root systems) and in charcoal. The roots rot, as described above: that carbon is sequestered. The unburned wood above ground eventually rots as well; more sequestering. The char weathers into small bits over time and eventually enters the soil as biochar. That carbon is not only sequestered, but has become an important substrate to an enriched ecosystem. [One gram of biochar has an active surface area the size of a tennis court, which captures micro nutrients for slow release as the ecosystem can absorb them, and filters out heavy metals and other pollutants.]
In a forest fire, the ratio of carbon that remains sequestered to carbon that goes atmospheric as CO2 is somewhere between 1:4 and 1:2. Not all of the carbon in a forest is burned in a fire; somewhere between 25% and 33% is retained, basically forever, in the ecosystem as it recovers.
Will