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The problem is that California has the flu and people think its cancer. Getting the flu sucks but you're probably not gonna die. I remember forest fires as well as mudslides in CA back in the 1970s. Perhaps the last few years were an extreme, but note that going to that extreme and back took about a decade. Most people haven't been there long enough to know what normal is and just buy in to all the media hype.

Sorry, but this is just flat out wrong. Yes, drought and fire have always been a fact of life for California. But if you map the frequency and severity of fires alone, it’s on a remarkably upward trajectory over the past two decades. It’s climate change.

If go back a bit further you'll find that (for example) one of the big, deadly wildfires from a couple of years ago was almost identical to a wildfire that happened in that same area back in the 1960s (IIRC). And during that earlier fire a few structures burned too (there weren't that many around at the time), so thinking ahead they banned any further construction in the most dangerous part of that area. Only to conveniently forget about that ban during the 1980s and later, so in the second fire you now had a much higher human toll. So two almost identical fires but with very different outcomes, at least in human terms.

Also, most people apparently don't understand the distinction between "wildfire" and "firestorm". Since upwards of 97% of wildfires are actually human-caused these days, of course a human has to be present for that to happen. No humans means far fewer wildfires.

But a lot of what we've been seeing lately are actually firestorms, where a single structure catches fire and then that spreads uncontrollably to the next structure and so on until everything flammable is basically burned out. Firestorms happen because there are few if any resources available to put the fire out while it's still small. So while the original source of ignition may very well have come from a wildfire, the firestorm can keep burning and spreading long after the wildfire itself has basically played out, at least in that immediate area.

And no, climate change has little or nothing to do with this.

The Native Americans used to set fire to the landscape every year - at least in Oregon, and I’m pretty sure California to a degree as well. I think California was literally on fire the first time missionaries sailed up the coast.

I agree - controlled burns are effective at keeping brush at manageable levels, and fire is a natural part of the forest ecosystem. And part of California’s climate. Developing too close to the wilderness edge is putting more human lives at risk. (I own farm and forest land, and am involved in conservation and restoration; I’m familiar with the challenges.)

But Climate Change is rapidly becoming the dominate factor for one simple reason: hot, dry, things burn. And Climate Change is making things hotter and drier.


Funny you should mention "hot, dry, things burn". I once did a little digging into the matter, and it turns out that once ignition temperature is reached, the difference between a fresh green leaf igniting vs. a dry brown one is on the order of just a few seconds, maybe just one or two. Which is surprisingly fast, but not so surprising when you realize that advancing flame fronts may be in the high hundreds to low thousands of degrees - plenty hot enough to quickly desiccate even the freshest leaf. It turns out that bigger factors are the size and shape of the leaf in question, what type of plant it is, and of course what the winds are doing.

Physical wetness, though, may make quite a bit of difference, especially when it comes to a fire actually igniting to begin with. But even that may not matter so much when it comes to things like lightning strikes, which may be in the tens of thousands of degrees.

So, for example, if the temperature might normally be 70F but instead is closer to 100F, that small difference is minimal compared to the temperature of any flames. But it might make a huge difference to someone fighting those flames, unless maybe they are right in the thick of them.

Over the past two decades, yes. But humans have been in California for a lot longer than two decades. Over all the time humans have been in California (which is basically since the last Ice Age at least, possibly longer since we don't know exactly when it was first settled by Native Americans), what we're seeing now is probably well within the range of variation. We can't know for sure because we don't have 12,000 years worth of records to tell us.

Which means we don't have the basis for saying that what's been happening in California over the past couple of decades is an emergency. It might just be part of the long term cost of choosing to live in California.

Yes, but this is the same argument people make about how you can’t attribute a given hurricane to Climate Change (although science has becoming more capable of those kinds of attributions in recent years).

Yes, climate fluctuates. Yes, there have plausibly been years of drought and fire in centuries past that would rival recent years. But absent the specific data you say is lacking, if you believe that climate science is generally correct, then more drought, more warming, more fire is the obvious trend. Not just California, but the entire world.

Regardless of whether similar events have happened in the past, there’s an obvious reason for the dramatic uptick between the 1970s and today: CO2 in the atmosphere, put there by humans.

> there’s an obvious reason for the dramatic uptick between the 1970s and today: CO2 in the atmosphere, put there by humans

The fact that this reason is "obvious" doesn't mean it's correct. Climate models based on the assumption that human CO2 emissions are the primary cause of warming have been significantly over-predicting warming. So I don't think we can say human CO2 emissions are the primary cause. We are still too uncertain about how the climate works for that.

> But if you map the frequency and severity of fires alone, it’s on a remarkably upward trajectory over the past two decades. It’s climate change.

...or it could be because the forests are so out of balance because they need fire to thrive that smaller events have oversized effects.

Before people started blaming severe forest fires on climate change they blamed the fires on the policy of systematically putting out all fires which allowed fuel to pile up on the forest floor allowing them to burn much hotter resulting in the trees dying. Before this policy the fires would just burn through the underbrush and the trees would survive as this is how they evolved.

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