Fire Season

[ursus arctos]

This is the best piece I’ve seen on 45’s “strikingly ignorant” tweets about the California fires.

No one would mistake President Donald Trump for an expert on climate change or water policy, but a tweet he issued late Sunday about California's wildfires deserves some sort of award for most glaring misstatements about those two issues in the smallest number of words.
. . .

The likeliest explanation for his take on water is that he's confused by the demands for more irrigation water he's hearing from Republican officeholders in the Central Valley. They're the people who grouse about water being "wasted" by being diverted to the ocean, rather than into their fields.

The Mendocino Complex is now the second largest fire in state history.

[Guy Profumo]

https://twitter.com/realDonaldTrump/status/1026228024403021824

https://twitter.com/realDonaldTrump/status/1026524292396273664

I don't know if anyone can figure out what he is talking about.

Rivers, presumably?

[Incandenza]

But if California currently isn't allowing the Free Flow of the vast amounts of water and is instead diverting that to the ocean...is he thinking that all rivers are like the LA River, and have some giant engineered path instead? And does he think that they would instead be all collecting in some giant reservoir?

[ursus arctos]

He doesn't think, Inca.

You should know that by now.

[San Bernardhinault]

It's surely actually all about the few CA Republicans in the Central Valley, and farmers whining about water rights. He's probably somehow conflated a fire up near Lake Shasta and billionaire almond farmers in Devin Nunes district that Nunes is trying to help by getting huge amounts of water pumped for free from NorCal.

[WOM]

They should all get on the Selleck Plan...or is that only for avacado farmers?

[ursus arctos]

SB, exactly (and as outlined in the SacBee piece I posted yesterday)

[ursus arctos]

Now the largest fire in state history, approaching the size of Los Angeles

https://twitter.com/washingtonpost/status/1026931168158134276?s=21

https://twitter.com/washingtonpost/s...158134276?s=21

[linus]

Here's a bit of historic context as far as the extent of burnt areas:



In the 1930s, areas the size of large states, not cities, used to burn every year. In 1930 the total area burned in the US was the size of Kansas or Nebraska. Incidentally, the 1930s were still way hotter in N. American than the current decade, most of the records set from that decade still stand, and this despite the urban heat island effect, which was very marginal back then.


And in California, fire activity has been relatively low the past decades, which will add to the fuel load:



The fuel load in California has nearly doubled in the last 3-4 decades (See report pg. 7: https://www.epw.senate.gov/public/_c...imonysouth.pdf)

[anton pulisov]

The reduction in burning has a lot to do with forest management brought in by FDR. In fact, the sharp downward trend in fires coincides with the start of the New Deal. Increasing population near forested areas also led to less tolerance of fires and more demand and more tax dollars for forest management. They've been pretty successful, considering that they've managed to keep forest fires down while enlarging the forested areas after their post-deforestation dust bowl low.

[linus]

US forest area has been pretty stable over the last century, the statistics don't bear out the FDR Dust Bowl narrative:

[IMG]https://cdn-images-1.medium.com/max/1000/1*1BMhrKUNPBC70uZWVlANQw.png[/IMG]

https://cdn-images-1.medium.com/max/...0uZWVlANQw.png

You've had aggressive active fire suppression/management policies over the past half century, so you'd expect a steady buildup in the volume of fuel load. This contributes to the extent of recent fires.

[anton pulisov]

Well, they do controlled burning of forests in California, so they are aware of that problem. Maybe they haven't done enough.

I would agree however that there are too many attention seeking scientists out there screaming climate change regarding these fires. I find many of those scientists to be irresponsible because by attributing everything to climate change they undermine the good work done on climate change by proper scientists who consider all the errors and uncertainties. Unfortunately it is the former group of scientists who are more likely to get funding or get their work published in corporate click-bait journals like Nature.

[San Bernardhinault]

In fairness, the trend to a longer fire season is probably driven by climate change. The trend to warmer winters and drier summers creating more favourable burn conditions is certainly not unrelated to climate change.

But when they try and pin individual fires, even big ones, on climate change, it's clearly attention seeking nonsense, or (more likely) being prodded to it by the media who find it an easy story.

[linus]

Actually, the trend in N. America has been towards cooler summers and colder winters.



With the exception of the 80s-90s which saw a warming, the region has seen mostly cooling since the peak temperatures of the 1930s. The great majority of all-time heat records are still from the 1930s.



https://www.epa.gov/climate-indicato...w-temperatures

[San Bernardhinault]

You've cherry picked a ridiculously narrow time range for your top graph.

[Snake Plissken]

And the trend in the bottom one from the 1960s onwards is an upward one.

[Hot Pepsi]

North America as a whole is not a very useful unit of study, but it would stand to reason given that climate change has caused the jet stream to meander more which is, as I understand it, why we’ve had more of those weeks where the polar air parks itself over the northern US and also perhaps why tropical storms are able to stay longer.

https://www.npr.org/sections/thetwo-...weather-events


Climate change is certainly making a difference in Colorado. There is less snowpack and the pine beetles are killing a lot more trees. A good friend of mine teaches at CSU and this is his thing.

https://www.yaleclimateconnections.o...uncertainties/

But I imagine other anthropogenic factors may be even more important - water use, suburban sprawl, pollution, and who knows what.

[WOM]

I had to put a sweater on earlier....

[linus]

And the trend in the bottom one from the 1960s onwards is an upward one.

(1) you're totally ignoring the 800lb gorilla staring at you in that graph, the fact that the frequency and intensity of heat waves today is nowhere near what it was in the 1930s.

(2)The recent upward trend is well within historic standards, and is of course several orders of magnitude smaller than the 1930s spike.

Furthermore, most of the recent upwards trend is attributable to the urban heat island effect, which skews temperatures upwards by up to 4C-5C in urban areas. Very often weather stations that used to be located in rural areas or exurbs become urban stations due to the dynamic American urbanization pattern, with which many of our European-based posters are not intimately familiar. The most telling feature of UHI is its dramatic effect on nighttime temperatures.

[San Bernardhinault]

You're obviously ignoring some other gorillas here.

Such as that the localised 1930s anomaly wasn't matched elsewhere on the planet. The 60 year trend since 1960 is longer term and matches global conditions.

And that you've cherry picked the most extreme graph for the 1930s, which uses "Heat Wave Index" which I believe is a compound variable of all kinds of things that doesn't just include heat and lack of rainfall, but also soil moisture conditions and water table levels and so on, and is thus much more extreme because of terrible land-use practices in the great plains in the early 20th century.

If you look at - say - the actual land temperatures in the US, you get a different picture, of a couple of outlier years in the 30s with cold years either side, but a continuous bloc of basically 40 outlier years all together since 1980.



(And a reminder that, of course, choosing to look at US rather than global data is its own cherry-picking problem)

[linus]

You've cherry picked a ridiculously narrow time range for your top graph.

Any graph of US temperature history where the data hasn't been altered will show an overall decrease in temperature from the 1930s peak.



Supposedly current/recent temperatures are the highest ever, yet most of the all-time recorded highs were set in the 30s, and it's not even close:

[linus]

You're obviously ignoring some other gorillas here.

Such as that the localised 1930s anomaly wasn't matched elsewhere on the planet. The 60 year trend since 1960 is longer term and matches global conditions.

And that you've cherry picked the most extreme graph for the 1930s, which uses "Heat Wave Index" which I believe is a compound variable of all kinds of things that doesn't just include heat and lack of rainfall, but also soil moisture conditions and water table levels and so on, and is thus much more extreme because of terrible land-use practices in the great plains in the early 20th century.

If you look at - say - the actual land temperatures in the US, you get a different picture, of a couple of outlier years in the 30s with cold years either side, but a continuous bloc of basically 40 outlier years all together since 1980.

(And a reminder that, of course, choosing to look at US rather than global data is its own cherry-picking problem)

1- The focus on this thread was about US fires. In this context it is useful to point out that the current US temperatures are nowhere near their historic highs.

2- Heat waves/intense episodes of heat are extremely relevant in the context of fire.

3- Land-use practices have nothing to do with recorded temperatures. Recorded temperatures alone tell us that the current levels are quite ordinary.

4- You've stated "the localised 1930s anomaly wasn't matched elsewhere on the planet". Not true, here is a study showing changes in recorded temperatures averaged over the northern hemisphere, which shows a significant and steady cooling taking place for over 3 decades since the 1930s peak (note that this cooling occurred while CO2 levels were steadily and dramatically rising) :




Back in the 1970s there was a scientific consensus about the earth cooling, and the notion that we would be entering a catastrophic ice age was prevalent.

[San Bernardhinault]

1- The focus on this thread was about US fires. In this context it is useful to point out that the current US temperatures are nowhere near their historic highs.

The "historic highs" are not particularly relevant. What's relevant is the long term warming (and, to a degree drying) trend in Northern California. Two warm years back-to-back in 1935 and 1936 are not going to make the kind of difference that 40 warm years back to back from 1978 to 2018 makes. (They are also, of course, "recorded highs", and it's widely accepted that measurements from nearly a century aren't particularly accurate).

2- Heat waves/intense episodes of heat are extremely relevant in the context of fire.

Heat waves are, at best, only part of the story. California's burning like crazy now because of a strong rainy season a year and a bit ago.

3- Land-use practices have nothing to do with recorded temperatures. Recorded temperatures alone tell us that the current levels are quite ordinary.

Your graph was showing Heat Wave Index, which is not a measurement of temperature, and is dependent on land use practices which is why it's so anomalously high in the graph you highlighted

4- You've stated "the localised 1930s anomaly wasn't matched elsewhere on the planet". Not true, here is a study showing changes in recorded temperatures averaged over the northern hemisphere, which shows a significant and steady cooling taking place for over 3 decades since the 1930s peak (note that this cooling occurred while CO2 levels were steadily and dramatically rising) :

Nice to show a graph from 1975... This is desperate stuff.

Back in the 1970s there was a scientific consensus about the earth cooling, and the notion that we would be entering a catastrophic ice age was prevalent.

Ha. It wasn't the consensus. But even if it was, this is an amazingly poor line of argument: scientists were wrong once, so why aren't they wrong now? Scientists thought the earth was flat once. Now they think it's a spheroid. How can you trust them, eh?

[linus]

North America as a whole is not a very useful unit of study, but it would stand to reason given that climate change has caused the jet stream to meander more which is, as I understand it, why we’ve had more of those weeks where the polar air parks itself over the northern US and also perhaps why tropical storms are able to stay longer.

https://www.npr.org/sections/thetwo-...weather-events


Climate change is certainly making a difference in Colorado. There is less snowpack and the pine beetles are killing a lot more trees. A good friend of mine teaches at CSU and this is his thing.

https://www.yaleclimateconnections.o...uncertainties/

But I imagine other anthropogenic factors may be even more important - water use, suburban sprawl, pollution, and who knows what.

The picture for the Colorado snowpack doesn't look very dramatic:

[linus]

1- The focus on this thread was about US fires. In this context it is useful to point out that the current US temperatures are nowhere near their historic highs.

The "historic highs" are not particularly relevant. What's relevant is the long term warming (and, to a degree drying) trend in Northern California. Two warm years back-to-back in 1935 and 1936 are not going to make the kind of difference that 40 warm years back to back from 1978 to 2018 makes. (They are also, of course, "recorded highs", and it's widely accepted that measurements from nearly a century aren't particularly accurate).

It wasn't two warm years back to back, the 1930s-40s were an extended plateau of higher temperatures. Temperatures recorded in the 20th century were quite accurate, you could get a consistent measurement to the tenth of a degree using analog methods. And unlike the temperatures from the past decades they weren't subject to massive and repeated politically motivated alterations that consistently cooled the past and warmed the present.

3- Land-use practices have nothing to do with recorded temperatures. Recorded temperatures alone tell us that the current levels are quite ordinary.

Your graph was showing Heat Wave Index, which is not a measurement of temperature, and is dependent on land use practices which is why it's so anomalously high in the graph you highlighted

4- You've stated "the localised 1930s anomaly wasn't matched elsewhere on the planet". Not true, here is a study showing changes in recorded temperatures averaged over the northern hemisphere, which shows a significant and steady cooling taking place for over 3 decades since the 1930s peak (note that this cooling occurred while CO2 levels were steadily and dramatically rising) :

Nice to show a graph from 1975... This is desperate stuff.

Back in the 1970s there was a scientific consensus about the earth cooling, and the notion that we would be entering a catastrophic ice age was prevalent.

Ha. It wasn't the consensus. But even if it was, this is an amazingly poor line of argument: scientists were wrong once, so why aren't they wrong now? Scientists thought the earth was flat once. Now they think it's a spheroid. How can you trust them, eh?

Are you really comparing a scientific consensus from the 1970s to that from the middle ages? desperate stuff indeed...

The graph I've presented destroys your theory of the 1930s hot decade being an American anomaly, and it showed the evolution of global temperatures over an entire century.



As well it directly contradicts the notion that CO2 is the main driver of global climate, because there was a steep rise in temperature from about 1900 to 1940, period when CO2 levels were low and growing slowly, followed by a marked decline in temperatures between 1940 and 1975, a period of rapid global industrialization and steeper increase in CO2 levels.