Arctic Sea Ice Extent, Area, and Volume

[BillT]

14 minutes ago, donsutherland1 said:

The above reasoning is deeply flawed.

For example, assume a hypothetical scenario where one has prolonged exposure to a heat index of 110° and winds up suffering from a heat-related health issue. Drawn from the above reasoning, one would assert that the high heat index wasn't responsible (after all, the heat index is merely an equation) and, by extension, some other issue led to the person's health issues (rather than the combination of heat and relative humidity, as measured by the heat index). That's the argument being made to deny that climate change has any link to the California wildfires. The empirical evidence in numerous published papers demonstrates the existence of such a link.

Put simply, the measurements don't cause issues. But the underlying phenomena being measured or described--in this case, climate change--have very real consequences.

the heat index is the actual heat and an equation using the relative humidity, that is nothing akin to the climate stats it is about the actual current conditions, exposure to extreme heat having an impact on ones health has nothing to do with the "climate".......and please learn there is a "link" between every past event in weather and the "climate" and also learn a "link"says ZERO about the "cause".....the same links between weather and climate has always existed there is NO change in that reality.

[donsutherland1]

1 hour ago, BillT said:

the heat index is the actual heat and an equation using the relative humidity, that is nothing akin to the climate stats it is about the actual current conditions, exposure to extreme heat having an impact on ones health has nothing to do with the "climate".......and please learn there is a "link" between every past event in weather and the "climate" and also learn a "link"says ZERO about the "cause".....the same links between weather and climate has always existed there is NO change in that reality.

The semantics arguments used to deny climate change in general and the link between climate change and the incidence of wildfire in particular are not supported by the scientific literature and they are unconvincing in evidence-based discussion.

First, regarding the semantics arguments:

1. "Climate change" or "anthropogenic climate change" are terms that describe shifts in the climate that are underway. That description concerns heat, precipitation, the cryosphere, etc.
2. Those elements are actual things, not abstract matters.
3. No one has suggested that there isn't a link between weather and climate.
4. The predominant cause of climate change is the increased greenhouse gas forcing due to anthropogenic contributions that have led to an imbalance between greenhouse gas emissions and greenhouse gas absorption. The end result is the documented increase in the atmospheric concentration of such gases, leading to increased forcing from such gases.
5. The physical properties of such gases are well-established (and in the case of carbon dioxide have been known since the 19th century). These properties have not changed. Only the mechanism by which they have been released from storage via burning of fossil fuels has changed.
6. The increasing atmospheric concentration of such gases have been driving changes that are captured in the description "climate change."
7. Those changes have been linked to, among other things, the increased risk of wildfires.

Now, onto the link to climate change:

One such study revealed:

We demonstrate that human-caused climate change caused over half of the documented increases in fuel aridity since the 1970s and doubled the cumulative forest fire area since 1984. This analysis suggests that anthropogenic climate change will continue to chronically enhance the potential for western US forest fire activity while fuels are not limiting.

https://www.pnas.org/content/pnas/113/42/11770.full.pdf

An even more recent study:

Recent fire seasons have fueled intense speculation regarding the effect of anthropogenic climate change on wildfire in western North America and especially in California. During 1972–2018, California experienced a fivefold increase in annual burned area, mainly due to more than an eightfold increase in summer forest‐fire extent. Increased summer forest‐fire area very likely occurred due to increased atmospheric aridity caused by warming. Since the early 1970s, warm‐season days warmed by approximately 1.4 °C as part of a centennial warming trend, significantly increasing the atmospheric vapor pressure deficit (VPD). These trends are consistent with anthropogenic trends simulated by climate models. The response of summer forest‐fire area to VPD is exponential, meaning that warming has grown increasingly impactful. Robust interannual relationships between VPD and summer forest‐fire area strongly suggest that nearly all of the increase in summer forest‐fire area during 1972–2018 was driven by increased VPD. Climate change effects on summer wildfire were less evident in nonforested lands. In fall, wind events and delayed onset of winter precipitation are the dominant promoters of wildfire. While these variables did not change much over the past century, background warming and consequent fuel drying is increasingly enhancing the potential for large fall wildfires. Among the many processes important to California's diverse fire regimes, warming‐driven fuel drying is the clearest link between anthropogenic climate change and increased California wildfire activity to date.

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2019EF001210

Do you have examples of papers published during the past 5-10 years that conclude that there is no link between climate change and the increased risk of wildfire?

[BillT]

i prefer discussing issues and using my own brain, the "studies" you so much prefer are PAID to find the results they find........real science says there is nothing unusual going on now that hasnt gone on for eons.....co2 levels have been much higher in the past and YOU cant blame humans for that FACT.......

[bdgwx]

On 10/29/2019 at 12:35 PM, BillT said:

i see meaningless jibberish in that graph.....

I believe the point of the graph was to test your comprehension of noisy information. This is actually a carefully studied topic in academia especially in the context of climate data in which there is a disproportionate number of analysis out there in the blogosphere that suffer from various cognitive biases.

I want you to get started with this paper.

Daron et al, 2015: Interpreting climate data visualisations to inform adaptation decisions

There are many well documented cognitive biases that influence an individual's comprehension of a graph. They include but are not limited to anchoring, framing, etc. In a nutshell when individuals are presented with a plot of noisy data some of them are incapable of mentally forming a linear or exponential regression trendline in their head. 

 

[bdgwx]

4 hours ago, BillT said:

i prefer discussing issues and using my own brain, the "studies" you so much prefer are PAID to find the results they find........real science says there is nothing unusual going on now that hasnt gone on for eons.....co2 levels have been much higher in the past and YOU cant blame humans for that FACT.......

Just understand that natural CO2 molecules have the same radiation behavior as anthroprogenic CO2 molecules. So an anthrprogenic pulse of CO2 (like with fossil fuel combustion and cement production) will lead to the same amount of warming as a natural pulse of CO2 (like which occurred during the PETM) given the same magnitude of the pulse. In that manner the laws of physics don't really care how the CO2 got into the atmosphere. I also sense a bit of the logical fallacy affirming a disjunct. Just because CO2 was naturally modulated in the past doesn't mean that it can't be anthroprogenically modulated today and cause warming.

And yes, CO2 levels were much higher in the past. This is an essential piece in the puzzle in solving the faint young Sun problem. Remember, solar output is about 1% weaker for every 120 million years in the past. 600 mya the solar radiative force was about -12 W/m^2 (see Gough 1981). So it would take ~9.5x the amount of CO2 just to offset the reduced solar forcing of the past relative to today (note that 5.35 * ln(9.5) = +12 W/m^2).

[tamarack]

1 hour ago, donsutherland1 said:

 

 

An even more recent study:

Recent fire seasons have fueled intense speculation regarding the effect of anthropogenic climate change on wildfire in western North America and especially in California. During 1972–2018, California experienced a fivefold increase in annual burned area, mainly due to more than an eightfold increase in summer forest‐fire extent. Increased summer forest‐fire area very likely occurred due to increased atmospheric aridity caused by warming. Since the early 1970s, warm‐season days warmed by approximately 1.4 °C as part of a centennial warming trend, significantly increasing the atmospheric vapor pressure deficit (VPD). These trends are consistent with anthropogenic trends simulated by climate models. The response of summer forest‐fire area to VPD is exponential, meaning that warming has grown increasingly impactful. Robust interannual relationships between VPD and summer forest‐fire area strongly suggest that nearly all of the increase in summer forest‐fire area during 1972–2018 was driven by increased VPD. Climate change effects on summer wildfire were less evident in nonforested lands. In fall, wind events and delayed onset of winter precipitation are the dominant promoters of wildfire. While these variables did not change much over the past century, background warming and consequent fuel drying is increasingly enhancing the potential for large fall wildfires. Among the many processes important to California's diverse fire regimes, warming‐driven fuel drying is the clearest link between anthropogenic climate change and increased California wildfire activity to date.

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2019EF001210

Was forest management (especially fuel management or lack of same), considered by this study as a possible contributing factor for the massive increase in burn area?  Perhaps it's not a major factor, but I hope it was part of the data that was used.
(Would read the link but I'm headed home.)

[BillT]

the greenhouse effect is an insulating effect.....can anybody here name any insulator that ADDS heat to the system it is insulating?

my understanding of insulation is it SLOWS the movement of the heat energy but in no way traps that heat and does NOT in any way ADD any extra heat to the system.....

if my understanding is wrong please show an insulator that ADDS heat?

 

[etudiant]

11 minutes ago, BillT said:

the greenhouse effect is an insulating effect.....can anybody here name any insulator that ADDS heat to the system it is insulating?

my understanding of insulation is it SLOWS the movement of the heat energy but in no way traps that heat and does NOT in any way ADD any extra heat to the system.....

if my understanding is wrong please show an insulator that ADDS heat?

 

Afaik, the issue here is that incoming energy from the sun is more short wave, which is not as obstructed by greenhouse gases as are the longer wave length heat radiations,

The effect is same energy incoming, less outgoing, resulting in a heating effect. 

Note that this leaves lots of room for discussion, as we have no full agreement on the effects of water vapor, the predominant green house gas, or of clouds, or of atmospheric convection, ocean heat flows etc etc. It is a very complex system and it is frankly a major achievement to have it modeled as well as it is. Major uncertainties still remain, but the existence of greenhouse effects is not one of them.

[BillT]

6 minutes ago, etudiant said:

Afaik, the issue here is that incoming energy from the sun is more short wave, which is not as obstructed by greenhouse gases as are the longer wave length heat radiations,

The effect is same energy incoming, less outgoing, resulting in a heating effect. 

Note that this leaves lots of room for discussion, as we have no full agreement on the effects of water vapor, the predominant green house gas, or of clouds, or of atmospheric convection, ocean heat flows etc etc. It is a very complex system and it is frankly a major achievement to have it modeled as well as it is. Major uncertainties still remain, but the existence of greenhouse effects is not one of them.

i agree and will add it is far too complex to single out human released co2 and claim it is the driver of our climate.

[donsutherland1]

1 hour ago, tamarack said:

Was forest management (especially fuel management or lack of same), considered by this study as a possible contributing factor for the massive increase in burn area?  Perhaps it's not a major factor, but I hope it was part of the data that was used.
(Would read the link but I'm headed home.)

Forest management was considered.

Excerpts:

The above results strongly suggest that the observed increase in California summer burned area during1972–2018 (which mainly occurred in northern California forests) was mainly due to increased VPD and not concurrent changes in nonclimate factors such as forest management, fire suppression practices, or human ignitions. This is not to say that nonclimate factors were negligible in dictating modern annual burned areas. To the contrary, human ignitions greatly enhance the number of wildfires relative to that expected in their absence (Balch et al., 2017), and increased fuel density due tofire suppression (and warming/wetting trends in the high Sierra) may have enhanced the mean state of modern‐day forest‐fire extent, severity, and sensitivity to aridity (Dolanc et al., 2013; Harris & Taylor, 2015; Minnich et al., 1995;Swetnam & Baisan, 1996).

[ORH_wxman]

13 hours ago, LibertyBell said:

Thought I should post this update, especially with the recent historic forest fires all over California and now in Los Angeles!

 

https://twitter.com/RyanMaue/status/1188160398320656385

 

The climate science is settled on direct causal links to California wildfires.  

 

Whether it is drier droughts, or whiplashes to wetness, the jet stream is acting freakishly.  

 

The fingerprints of climate change are all over this current event.

 

https://t.co/avouF71zBo?amp=1

 

https://www.sfchronicle.com/science/article/Scientists-see-fingerprints-of-climate-change-all-13128585.php

 

 

It's actually not clear at all for "the current event" given that the autumn attribution is extremely weak to non-existent. It seems the trends are stronger for summer. From the most recent paper you linked:

 

This is the problem with some of the attribution studies that are in a shorter time span. Esp starting in the middle 20th century. 

[bdgwx]

2 hours ago, BillT said:

the greenhouse effect is an insulating effect.....can anybody here name any insulator that ADDS heat to the system it is insulating?

my understanding of insulation is it SLOWS the movement of the heat energy but in no way traps that heat and does NOT in any way ADD any extra heat to the system.....

if my understanding is wrong please show an insulator that ADDS heat?

 

CO2 does not add heat. It traps heat. In this context "trap" means to slow the egress transmission of heat without slowing the ingress transmission of heat.

The insulation in your home acts as a thermal barrier to trap heat. The furnace adds energy to your home. Because the insulation has changed the rate at which heat is lost your home will achieve a higher equilibrium temperature with the insulation than it would otherwise. But the furnace is still the energy source.

...similarly...

The GHGs in Earth's atmosphere act as a thermal barrier to trap heat. The Sun adds energy to the Earth. Because the GHGs have changed the rate at which heat is lost the Earth will achieve a higher equilibrium temperature with the GHGs than it would otherwise. But the Sun is still the energy source.

[donsutherland1]

4 hours ago, BillT said:

i prefer discussing issues and using my own brain, the "studies" you so much prefer are PAID to find the results they find........real science says there is nothing unusual going on now that hasnt gone on for eons.....co2 levels have been much higher in the past and YOU cant blame humans for that FACT.......

What is "real science?" If one is ignoring scientific research, how can one even make claims about science?

As for the latter part about past higher CO2 levels, none of that means that humans can't be responsible for unlocking greenhouse gases when, prior to the emergence of humans, natural processes were the only means possible.

[ORH_wxman]

2 hours ago, donsutherland1 said:

Forest management was considered.

Excerpts:

The above results strongly suggest that the observed increase in California summer burned area during1972–2018 (which mainly occurred in northern California forests) was mainly due to increased VPD and not concurrent changes in nonclimate factors such as forest management, fire suppression practices, or human ignitions. This is not to say that nonclimate factors were negligible in dictating modern annual burned areas. To the contrary, human ignitions greatly enhance the number of wildfires relative to that expected in their absence (Balch et al., 2017), and increased fuel density due tofire suppression (and warming/wetting trends in the high Sierra) may have enhanced the mean state of modern‐day forest‐fire extent, severity, and sensitivity to aridity (Dolanc et al., 2013; Harris & Taylor, 2015; Minnich et al., 1995;Swetnam & Baisan, 1996).

They didn't attempt to quantify the non-climate factors though which was a bit frustrating in reading the study. I just finished reading it and they sort of just decide that VPD fits well enough that it is dominant. That might be true but it would have been nice to try and isolate it from the non-climate factors which they admitted is something they weren't doing in the paper...so we could see numerically how dominant it actually is. 

[donsutherland1]

Just now, ORH_wxman said:

They didn't attempt to quantify the non-climate factors though which was a bit frustrating in reading the study. I just finished reading it and they sort of just decide that VPI fits well enough that it is dominant. That might be true but it would have been nice to try and isolate it from the non-climate factors which they admitted is something they weren't doing in the paper...so we could see numerically how dominant it actually is. 

I agree that greater precision would be helpful. I just wanted to note that the issue was considered.

[ORH_wxman]

4 hours ago, BillT said:

i prefer discussing issues and using my own brain, the "studies" you so much prefer are PAID to find the results they find........real science says there is nothing unusual going on now that hasnt gone on for eons.....co2 levels have been much higher in the past and YOU cant blame humans for that FACT.......

There's plenty of peer review research to read that will argue humans aren't responsible for the increase in CO2, but in reading them, you'll note that they don't hold up under scrutiny as time passes and other papers rebut them and they aren't able to counter those rebuttals. So they are fewer and fewer these days. I would suggest reading literature across all spectrums and not try and muck up the thread by insisting you know more than these papers. 

[bdgwx]

So in an effort to steer this thread back on track...it looks like the refreeze has really ramped up lately. We are still in record territory for this time of year, but it looks like 2019 might jump ahead of 2016 in the next week or so.

[donsutherland1]

13 minutes ago, bdgwx said:

So in an effort to steer this thread back on track...it looks like the refreeze has really ramped up lately. We are still in record territory for this time of year, but it looks like 2019 might jump ahead of 2016 in the next week or so.

On JAXA, 2019 has already moved ahead of 2016: 7.063 million square kilometers vs. 6.841 million square kilometers in 2016.

[tamarack]

14 hours ago, donsutherland1 said:

Forest management was considered.

Excerpts:

The above results strongly suggest that the observed increase in California summer burned area during1972–2018 (which mainly occurred in northern California forests) was mainly due to increased VPD and not concurrent changes in nonclimate factors such as forest management, fire suppression practices, or human ignitions. This is not to say that nonclimate factors were negligible in dictating modern annual burned areas. To the contrary, human ignitions greatly enhance the number of wildfires relative to that expected in their absence (Balch et al., 2017), and increased fuel density due tofire suppression (and warming/wetting trends in the high Sierra) may have enhanced the mean state of modern‐day forest‐fire extent, severity, and sensitivity to aridity (Dolanc et al., 2013; Harris & Taylor, 2015; Minnich et al., 1995;Swetnam & Baisan, 1996).

Thanks.  And I also thank you and Will for related follow-up comments.  As one who has worked as a forester since 1976 I'm always interested in things related to my vocation.

[DaculaWeather]

84% of fires are man made

https://www.smithsonianmag.com/smart-news/study-shows-84-wildfires-caused-humans-180962315/

Quote

According to a press release, researchers from the University of Colorado, Boulder’s Earth Lab took a deep dive into the U.S. Forest Service’s Fire Program Analysis-Fire Occurrence Database, analyzing all wildfires recorded between 1992 and 2012. The researchers found that humans caused more than 1.2 million of the 1.5 million blazes in the database.  

The cost of those human-induced fires is staggering. The researchers estimate that man-made fires have tripled the average fire season over the past 21 years from 46 days to 154 days. It now costs over $2 billion per year to fight the fires, and that figure does not include the impacts to recreational lands or local economic impact that fires can have.

Read more: https://www.smithsonianmag.com/smart-news/study-shows-84-wildfires-caused-humans-180962315/#1qPbqxlDiGrFUlcG.99
Give the gift of Smithsonian magazine for only $12! http://bit.ly/1cGUiGv
Follow us: @SmithsonianMag on Twitter

 

[bluewave]

Daniel Swain is probably one of the best sources of information on this topic. While all these California wildfire posts probably belong in a different thread, the information below helps people understand the issues involved.

https://insideclimatenews.org/news/13112018/california-deadly-wildfires-climate-change-dry-autumn-late-rainy-season-swain-interview

What does the recent data show in California? And how are these changes impacting overall rainfall?

We are starting to see a trend towards drier autumns in California. It's somewhat new, it's just emerging from the noise, one might say, but it is actually there. This year is going to add another data point in that direction.

It matches climate projections. There has long been an expectation that California's so-called shoulder season precipitation would probably decrease—that's autumn and spring. Now what we're starting to see is, especially in the autumn, that process now appears to be underway. It's both an emerging observation but also a projection for the future, a future that maybe isn't really the future any more.

That actually doesn't necessarily mean the overall amount of precipitation is decreasing. There's a growing overall concentration of water in the rainy season. Our research suggests that concentration will be a pretty strong indicator of California's future climate.

You've made the point that it's problematic to ask whether climate change causes a specific event. Why is that?

In any sort of natural system there's never really, in any context, a singular cause of anything.

It depends how you define causation, which then is a non-trivial task. It ends up being more meaningful to say, look, we're going to have fires no matter what. Whether they're caused naturally by lightning, by totally innocent human error or by more malicious human intent. It doesn't really matter what started the fire. But the question is, what factors contribute to what happened after the fire starts. The real question is not so much what caused it, because ultimately it doesn't really matter. The question is what made it as bad as it was.

Then you can get an answer that, yes, there is a link between wildfire behavior intensity and climate change.

As climate change progresses, what is expected to happen with wildfire season?

When it comes to wildfire trends, the last five years in California have really been something else. It's really been hard to watch. it's pretty rare to see such large, dramatic step changes as what we've seen in California in the last five to 10 years. We've broken every record, and we've broken them several times. Largest, most destructive, deadliest—all

 

[Typhoon Tip]

On 10/29/2019 at 1:48 PM, BillT said:

i also see a graph with clearly whatever is being measured is leveling off in the near now time area but the line drawn shows the OPPOSITE is shows a sharper increase in whatever is being measured, the line drawn does NOT match the graph.

that's because those right side lines go off the top edge  ... i.e., but clearly you studied it for awhile to tried and use your mind, so I say we are making progress. 

[superjames1992]

I thought this was an arctic sea ice thread?

[bluewave]

While the ESS is finally freezing up, Chukchi extent remains at record low levels for the end of October.

 

[donsutherland1]

47 minutes ago, bluewave said:

While the ESS is finally freezing up, Chukchi extent remains at record low levels for the end of October.

 

In large part, this is likely why Utqiagvik will have the highest September-October mean temperature on record this year by at least 2 degrees.

[LibertyBell]

On 10/29/2019 at 8:33 PM, ORH_wxman said:

There's plenty of peer review research to read that will argue humans aren't responsible for the increase in CO2, but in reading them, you'll note that they don't hold up under scrutiny as time passes and other papers rebut them and they aren't able to counter those rebuttals. So they are fewer and fewer these days. I would suggest reading literature across all spectrums and not try and muck up the thread by insisting you know more than these papers. 

The interesting thing is we were pretty well certain about this even back during the 80s.  Actually if you want to go even further back, Exxon's own scientists were aware of it in the 70s, but just like the Tobacco industry, they suppressed the research (which is part of the reason they are considered a cartel and not an industry.)

 

[LibertyBell]

On 10/29/2019 at 2:02 PM, donsutherland1 said:

The above reasoning is deeply flawed.

For example, assume a hypothetical scenario where one has prolonged exposure to a heat index of 110° and winds up suffering from a heat-related health issue. Drawn from the above reasoning, one would assert that the high heat index wasn't responsible (after all, the heat index is merely an equation) and, by extension, some other issue led to the person's health issues (rather than the combination of heat and relative humidity, as measured by the heat index). That's the argument being made to deny that climate change has any link to the California wildfires. The empirical evidence in numerous published papers demonstrates the existence of such a link.

Put simply, the measurements don't cause issues. But the underlying phenomena being measured or described--in this case, climate change--have very real consequences.

all you need to see is the trend from how the forest fire season has evolved from a short season to a year long occurrence.

[LibertyBell]

On 10/29/2019 at 3:16 PM, donsutherland1 said:

The semantics arguments used to deny climate change in general and the link between climate change and the incidence of wildfire in particular are not supported by the scientific literature and they are unconvincing in evidence-based discussion.

First, regarding the semantics arguments:

1. "Climate change" or "anthropogenic climate change" are terms that describe shifts in the climate that are underway. That description concerns heat, precipitation, the cryosphere, etc.
2. Those elements are actual things, not abstract matters.
3. No one has suggested that there isn't a link between weather and climate.
4. The predominant cause of climate change is the increased greenhouse gas forcing due to anthropogenic contributions that have led to an imbalance between greenhouse gas emissions and greenhouse gas absorption. The end result is the documented increase in the atmospheric concentration of such gases, leading to increased forcing from such gases.
5. The physical properties of such gases are well-established (and in the case of carbon dioxide have been known since the 19th century). These properties have not changed. Only the mechanism by which they have been released from storage via burning of fossil fuels has changed.
6. The increasing atmospheric concentration of such gases have been driving changes that are captured in the description "climate change."
7. Those changes have been linked to, among other things, the increased risk of wildfires.

Now, onto the link to climate change:

One such study revealed:

We demonstrate that human-caused climate change caused over half of the documented increases in fuel aridity since the 1970s and doubled the cumulative forest fire area since 1984. This analysis suggests that anthropogenic climate change will continue to chronically enhance the potential for western US forest fire activity while fuels are not limiting.

https://www.pnas.org/content/pnas/113/42/11770.full.pdf

An even more recent study:

Recent fire seasons have fueled intense speculation regarding the effect of anthropogenic climate change on wildfire in western North America and especially in California. During 1972–2018, California experienced a fivefold increase in annual burned area, mainly due to more than an eightfold increase in summer forest‐fire extent. Increased summer forest‐fire area very likely occurred due to increased atmospheric aridity caused by warming. Since the early 1970s, warm‐season days warmed by approximately 1.4 °C as part of a centennial warming trend, significantly increasing the atmospheric vapor pressure deficit (VPD). These trends are consistent with anthropogenic trends simulated by climate models. The response of summer forest‐fire area to VPD is exponential, meaning that warming has grown increasingly impactful. Robust interannual relationships between VPD and summer forest‐fire area strongly suggest that nearly all of the increase in summer forest‐fire area during 1972–2018 was driven by increased VPD. Climate change effects on summer wildfire were less evident in nonforested lands. In fall, wind events and delayed onset of winter precipitation are the dominant promoters of wildfire. While these variables did not change much over the past century, background warming and consequent fuel drying is increasingly enhancing the potential for large fall wildfires. Among the many processes important to California's diverse fire regimes, warming‐driven fuel drying is the clearest link between anthropogenic climate change and increased California wildfire activity to date.

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2019EF001210

Do you have examples of papers published during the past 5-10 years that conclude that there is no link between climate change and the increased risk of wildfire?

It's amazing that some people make the same "arguments" they made decades ago, they are just as invalid now as they were back then and are the reason we haven't made progress.

 

[LibertyBell]

On 10/29/2019 at 3:43 PM, BillT said:

i prefer discussing issues and using my own brain, the "studies" you so much prefer are PAID to find the results they find........real science says there is nothing unusual going on now that hasnt gone on for eons.....co2 levels have been much higher in the past and YOU cant blame humans for that FACT.......

paid for lol- you do realize you are talking about the fossil fuel CARTEL?! it's just as corrupt as the tobacco CARTEL or the pharma CARTEL or the ag CARTEL or the Colombian drug CARTEL ever were.

 

[LibertyBell]

On 10/30/2019 at 9:26 AM, bluewave said:

Daniel Swain is probably one of the best sources of information on this topic. While all these California wildfire posts probably belong in a different thread, the information below helps people understand the issues involved.

https://insideclimatenews.org/news/13112018/california-deadly-wildfires-climate-change-dry-autumn-late-rainy-season-swain-interview

What does the recent data show in California? And how are these changes impacting overall rainfall?

We are starting to see a trend towards drier autumns in California. It's somewhat new, it's just emerging from the noise, one might say, but it is actually there. This year is going to add another data point in that direction.

It matches climate projections. There has long been an expectation that California's so-called shoulder season precipitation would probably decrease—that's autumn and spring. Now what we're starting to see is, especially in the autumn, that process now appears to be underway. It's both an emerging observation but also a projection for the future, a future that maybe isn't really the future any more.

That actually doesn't necessarily mean the overall amount of precipitation is decreasing. There's a growing overall concentration of water in the rainy season. Our research suggests that concentration will be a pretty strong indicator of California's future climate.

You've made the point that it's problematic to ask whether climate change causes a specific event. Why is that?

In any sort of natural system there's never really, in any context, a singular cause of anything.

It depends how you define causation, which then is a non-trivial task. It ends up being more meaningful to say, look, we're going to have fires no matter what. Whether they're caused naturally by lightning, by totally innocent human error or by more malicious human intent. It doesn't really matter what started the fire. But the question is, what factors contribute to what happened after the fire starts. The real question is not so much what caused it, because ultimately it doesn't really matter. The question is what made it as bad as it was.

Then you can get an answer that, yes, there is a link between wildfire behavior intensity and climate change.

As climate change progresses, what is expected to happen with wildfire season?

When it comes to wildfire trends, the last five years in California have really been something else. It's really been hard to watch. it's pretty rare to see such large, dramatic step changes as what we've seen in California in the last five to 10 years. We've broken every record, and we've broken them several times. Largest, most destructive, deadliest—all

 

and it looks like this dry west pattern will continue for the foreseeable future!