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> The nonsense about blaming the forest service for putting out a few fires a century ago is like creationists asking why there are still apes if humans evolved

by Syonyk 4y ago

> The nonsense about blaming the forest service for putting out a few fires a century ago is like creationists asking why there are still apes if humans evolved from apes. I'm sorry, I can't agree with that. Have you seen charts of "acres burned per year" in the US for the time frame in question? I did a bunch of research on western forest fires some years back (summary here: https://www.sevarg.net/2018/08/12/wildfires-in-western-united-states/ https://www.sevarg.net/2018/08/12/wildfires-in-western-unite...), and part of that was creating a graph of "acres burned per year" based on some data sources that were only in textual format. I really should update it. https://www.sevarg.net/generated/images/2018-08-11/2018-08-11-fire_acres-768-e73a9fcd4.webp https://www.sevarg.net/generated/images/2018-08-11/2018-08-1... is the relevant chart. Back in the 1930s, north of 50M acres/year were burned. The Forest Service "10AM Policy" went into effect in 1935, and you can see the rapid reduction from 50M acres/yr down to 3-5M acres/yr by the 1960s. That low level sustained for quite a few years, and has been creeping back up towards around 10M acres/yr recently - you can find the raw data source I used, with a few more years than on that chart, here: https://www.nifc.gov/fire-information/statistics/wildfires https://www.nifc.gov/fire-information/statistics/wildfires So... I think your assertion that "it's 100% climate change," given the historical data I've presented, is lacking in evidence. Unless you're going to argue that, somehow, climate change was causing 5-8x the acres burned in the 1930s as now. My interpretation fits the evidence of "aggressive and capable wildfire fighting" as responsible for the vast reduction in acres burned, and that we're seeing just the start of a reversion to historical norms - which involve an awful lot more acres burned than even recent years.

Retric 4y ago
Acres burned per year is a poor metric as the amount of wild land has changed dramatically over time. 3.5 million people lived in CA in 1920 vs 10.3 million in 1950. The reality is you can find wildfires burning vigorously in areas that had a wildfire the year before. The state only has ~100 million ares of land in total. When that chart is showing annual averages of 50+ million ares that includes some of the same land being burned the previous year. Not that those statistics are going to be very accurate but it’s what we have.
- Syonyk 4y ago
  My numbers, I believe, are for the entire US - not just California.
  - Retric 4y ago
    Sure, but not all of CA let alone the US is at risk from forest fires, so the point stands. https://en.wikipedia.org/wiki/Death_Valley#/media/File:Death_Valley_Mesquite_Flats_Sand_Dunes_2013.jpg https://en.wikipedia.org/wiki/Death_Valley#/media/File:Death...
photochemsyn 4y ago
It's a complex issue. Comparisons to the early 20th century have issues - for example, California's human population was about five million then, and it's forty million now, and was twenty million in 1970. There's been deforestation, movement of people into the woods, some replacement of pines by oaks, etc. Regardless, the five-fold increase in wildfires since 1970 in California are closely correlated with the amount of moisture in soil and vegetation in the summer, and fossil-fueled global warming is the culprit for that shift: > "Most of the increase in burned area seen since 1972 has been because of an increase in summer forest fires, mostly in Northern California and the Sierras. That increase, in turn, can be almost entirely explained by a rise in aridity, which is caused by warming, and consistent with climate change models. Just a small amount of warming causes exponential increases in aridity, drying out fuels, so summer forest fires could get a lot worse with further warming if fuels remain abundant." https://www.nps.gov/articles/how-is-climate-change-already-impacting-california-wildfires.htm https://www.nps.gov/articles/how-is-climate-change-already-i...
cronix 4y ago
Do your numbers differentiate between intentional, planned burns vs natural fires (lightning, etc) or just lump them together to get "total acres burned?" My understanding is we used to do a lot more intentional burning.
- bombcar 4y ago
  There are two kinds of intentional burns - one where you intentionally light the fire to burn off an area (perhaps done after logging or refreshing a field) and one where you let an area burn because you don't care or don't want to defend it. I believe the metric here is just "total acres burned" and I doubt intentional burning would count for forty million acres which is just insanely large.

by Syonyk 4y ago

Retric 4y ago

Acres burned per year is a poor metric as the amount of wild land has changed dramatically over time. 3.5 million people lived in CA in 1920 vs 10.3 million in 1950. The reality is you can find wildfires burning vigorously in areas that had a wildfire the year before. The state only has ~100 million ares of land in total. When that chart is showing annual averages of 50+ million ares that includes some of the same land being burned the previous year. Not that those statistics are going to be very accurate but it’s what we have.

Syonyk 4y ago
My numbers, I believe, are for the entire US - not just California.
- Retric 4y ago
  Sure, but not all of CA let alone the US is at risk from forest fires, so the point stands. https://en.wikipedia.org/wiki/Death_Valley#/media/File:Death_Valley_Mesquite_Flats_Sand_Dunes_2013.jpg https://en.wikipedia.org/wiki/Death_Valley#/media/File:Death...

photochemsyn 4y ago

It's a complex issue. Comparisons to the early 20th century have issues - for example, California's human population was about five million then, and it's forty million now, and was twenty million in 1970. There's been deforestation, movement of people into the woods, some replacement of pines by oaks, etc. Regardless, the five-fold increase in wildfires since 1970 in California are closely correlated with the amount of moisture in soil and vegetation in the summer, and fossil-fueled global warming is the culprit for that shift: > "Most of the increase in burned area seen since 1972 has been because of an increase in summer forest fires, mostly in Northern California and the Sierras. That increase, in turn, can be almost entirely explained by a rise in aridity, which is caused by warming, and consistent with climate change models. Just a small amount of warming causes exponential increases in aridity, drying out fuels, so summer forest fires could get a lot worse with further warming if fuels remain abundant." https://www.nps.gov/articles/how-is-climate-change-already-impacting-california-wildfires.htm https://www.nps.gov/articles/how-is-climate-change-already-i...

cronix 4y ago

Do your numbers differentiate between intentional, planned burns vs natural fires (lightning, etc) or just lump them together to get "total acres burned?" My understanding is we used to do a lot more intentional burning.

bombcar 4y ago
There are two kinds of intentional burns - one where you intentionally light the fire to burn off an area (perhaps done after logging or refreshing a field) and one where you let an area burn because you don't care or don't want to defend it. I believe the metric here is just "total acres burned" and I doubt intentional burning would count for forty million acres which is just insanely large.