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"Old firefighting techniques have build up vast caches if flammable material that we cannot afford to remove by any other means than forest fires." I see this

"Old firefighting techniques have build up vast caches if flammable material that we cannot afford to remove by any other means than forest fires." I see this repeated a lot. Can you talk specifically about the effect of early/mid 20th century firefighting in the Big Basin fire as compared to the Australian bushfires last year, the Siberian fires in 2019, and the Amazon fires this year and last? I am not sure any prior firefighting occurred in Siberia. And I feel like a lot of people repeat that "firefighting has left too much fuel and that's causing these fires" as though it's conventional wisdom... but it's not quantified so I don't know if it's 100% of the cause or just contributing 10%. In fact, I don't even know how to measure the buildup of flammable material (kg/sq meter?) or how it effects fire intensity. It feels like the discussion around this can veer into being hopeful and unscientific.

hinkley 6y ago
Both can be true, and if anything I think I would agree that this means we need to be even more careful over the next 30-50 years than we ever have been (or, hopefully, will have to be again), because we have two fuckups paying dividends at the same time, and one of them is on that time scale. We already know that timber land in the Americas requires more active stewardship than colonial thinking suggests. These are not European forests. Microbial decay doesn't reduce the calories per acre the same way. Global warming makes the balance even more precarious. But there are ways we can address both of these problems which also serves as a carbon sink. As long as we do it before the dominant forest soil biome in North America flips to bacteria-dominant due to rising ambient temperatures.
EricE 6y ago
excess fuel means the fire burns hotter. So instead of being beneficial it’s destructive. Excess fuel means ladder fires - where fire gets high enough to engulf the crowns of the trees - are far more likely. Many conifers rely on fire to open their cones. Artificially suppressing fire stops that process of renewal. Those are just a few examples off the top of my head - this topic is well trod and a little poking around will provide even more context.

hinkley 6y ago

Both can be true, and if anything I think I would agree that this means we need to be even more careful over the next 30-50 years than we ever have been (or, hopefully, will have to be again), because we have two fuckups paying dividends at the same time, and one of them is on that time scale. We already know that timber land in the Americas requires more active stewardship than colonial thinking suggests. These are not European forests. Microbial decay doesn't reduce the calories per acre the same way. Global warming makes the balance even more precarious. But there are ways we can address both of these problems which also serves as a carbon sink. As long as we do it before the dominant forest soil biome in North America flips to bacteria-dominant due to rising ambient temperatures.

EricE 6y ago

excess fuel means the fire burns hotter. So instead of being beneficial it’s destructive. Excess fuel means ladder fires - where fire gets high enough to engulf the crowns of the trees - are far more likely. Many conifers rely on fire to open their cones. Artificially suppressing fire stops that process of renewal. Those are just a few examples off the top of my head - this topic is well trod and a little poking around will provide even more context.