Occasional Thoughts on Climate Change

[donsutherland1]

4 hours ago, WolfStock1 said:

 

Look at the context here though - the climate change discussion thread.

If this were a "weather events" thread - I would agree that there's no implication of a tie-in between the big France wildfire spike, and I wouldn't have made my point about having to look at the bigger picture.   

But since this is in fact a climate change discussion thread, and since there are lots of assertions out there that CC causes increase in wildfire activity - it seems reasonable that there's an assertion of implied tie-in with that set of stats that was posted; vis a vis France's big spike in wildfires being due to CC.   My point then of course being that no - it's not due to CC (the context of the thread), it's due to a localized weather event (and possibly other factors such as bad fire control management).

The extreme heat was more the focus of climate change in my post, which merely noted that France was "wildfire-swept." At least for now, my understanding is that the connection between climate change and extreme heatwaves is stronger than the more complex linkage between climate change and wildfires. Nevertheless, there is a fairly prominent link.

Since my initial post, World Weather Attribution (WWA) has published a rapid attribution report. Consistent with the expectations from a growing body of scientific literature, including one Nature piece talking about the future that I posted, climate change contributed. Excerpts:

In Spain, January 2026 was the wettest January of the last quarter of a century (AEMET, 2026). In particular, in the area affected by the Ávila–Madrid–Toledo fire, rainfall was 175% higher than usual, which allowed a great accumulation of plant biomass. The summer of 2026 began with record-breaking temperatures and a severe drought, both conditions exacerbated by human-caused climate change (WWA, 2026a; WWA, 2026b). This sequence resulted in high fuel loads that then dried to become highly flammable, increasing the intensity of the fires...

In 2025, WWA conducted two rapid attribution studies on fires in Spain and Portugal (WWA, 2025a) and Turkiye, Cyprus and Greece (WWA, 2025b), alongside a retrospective analysis of the entire wildfire season in several European regions (Keeping et al., 2026b). Across all three studies, we found that human-caused climate change was a key driver of the fire weather conditions, primarily through its influence on exceptionally high temperatures, but also by exacerbating drought conditions...

The weeks leading up to the fires were characterised by a succession of extreme heatwaves and low rainfall across much of Western Europe, despite it still being comparably early in the season. Recent studies have shown human-caused climate change increased the likelihood of these hot and dry antecedent conditions, which were essential for the development of the extreme fire weather that enabled the fires...

In both study regions observations show strong trends of increasing likelihood and severity with global warming. DSR7x values as extreme as those observed in central Spain in July 2026 are now at least 20 times more likely than in a pre-industrial climate. In the French regions the statistical model fits the data less closely and may underestimate the return period of the event, thus the result of an increase in likelihood by at least a factor two in southwest France is a conservative estimate...

A recent attribution study has shown that climate change is increasing the likelihood of severe soil moisture drought through higher atmospheric evaporative demand, while the same sequence of above-average winter rainfall followed by exceptional spring drying was identified as a key driver of the 2025 Iberian wildfires. 

Finally, the WWA rapid attribution report cites and links to a fairly large number of papers on fire weather in Europe, many of which have relevance to the impact of climate change.

[LibertyBell]

6 hours ago, donsutherland1 said:

The extreme heat was more the focus of climate change in my post, which merely noted that France was "wildfire-swept." At least for now, my understanding is that the connection between climate change and extreme heatwaves is stronger than the more complex linkage between climate change and wildfires. Nevertheless, there is a fairly prominent link.

Since my initial post, World Weather Attribution (WWA) has published a rapid attribution report. Consistent with the expectations from a growing body of scientific literature, including one Nature piece talking about the future that I posted, climate change contributed. Excerpts:

In Spain, January 2026 was the wettest January of the last quarter of a century (AEMET, 2026). In particular, in the area affected by the Ávila–Madrid–Toledo fire, rainfall was 175% higher than usual, which allowed a great accumulation of plant biomass. The summer of 2026 began with record-breaking temperatures and a severe drought, both conditions exacerbated by human-caused climate change (WWA, 2026a; WWA, 2026b). This sequence resulted in high fuel loads that then dried to become highly flammable, increasing the intensity of the fires...

In 2025, WWA conducted two rapid attribution studies on fires in Spain and Portugal (WWA, 2025a) and Turkiye, Cyprus and Greece (WWA, 2025b), alongside a retrospective analysis of the entire wildfire season in several European regions (Keeping et al., 2026b). Across all three studies, we found that human-caused climate change was a key driver of the fire weather conditions, primarily through its influence on exceptionally high temperatures, but also by exacerbating drought conditions...

The weeks leading up to the fires were characterised by a succession of extreme heatwaves and low rainfall across much of Western Europe, despite it still being comparably early in the season. Recent studies have shown human-caused climate change increased the likelihood of these hot and dry antecedent conditions, which were essential for the development of the extreme fire weather that enabled the fires...

In both study regions observations show strong trends of increasing likelihood and severity with global warming. DSR7x values as extreme as those observed in central Spain in July 2026 are now at least 20 times more likely than in a pre-industrial climate. In the French regions the statistical model fits the data less closely and may underestimate the return period of the event, thus the result of an increase in likelihood by at least a factor two in southwest France is a conservative estimate...

A recent attribution study has shown that climate change is increasing the likelihood of severe soil moisture drought through higher atmospheric evaporative demand, while the same sequence of above-average winter rainfall followed by exceptional spring drying was identified as a key driver of the 2025 Iberian wildfires. 

Finally, the WWA rapid attribution report cites and links to a fairly large number of papers on fire weather in Europe, many of which have relevance to the impact of climate change.

Climate change affects different places differently which is why I like this term better than global warming. For this region the warming is more in the winter.  This isn't just about 1936 either or even Central Park bad siting. 1966 still holds the heat records for both LGA and JFK 107 and 104. I'd argue that 107 at LGA from July 1966 is more impressive than the 108 at Newark from July 2011. And big heat domes aren't a new thing, 1980, 1983, 1988, 1991, 1993, 1995, 1999 and 2002 had plenty of them. It's why I consider the 1980s and 1990s to be hotter especially ranked by duration of heat waves and number of 100 degree days. 1993 is still untouched in that regard.

We can even go back to 1911 to see a heat dome as bad as 1936.  JULY 2-4 that year Mt Pocono hit 98 99 and 103 on consecutive days and since then has never been higher than 95. I thought that might have been some instrument error but Boston recorded their all time high of 104 during that same torrid stretch.

[donsutherland1]

6 hours ago, LibertyBell said:

Climate change affects different places differently which is why I like this term better than global warming. For this region the warming is more in the winter.  This isn't just about 1936 either or even Central Park bad siting. 1966 still holds the heat records for both LGA and JFK 107 and 104. I'd argue that 107 at LGA from July 1966 is more impressive than the 108 at Newark from July 2011. And big heat domes aren't a new thing, 1980, 1983, 1988, 1991, 1993, 1995, 1999 and 2002 had plenty of them. It's why I consider the 1980s and 1990s to be hotter especially ranked by duration of heat waves and number of 100 degree days. 1993 is still untouched in that regard.

We can even go back to 1911 to see a heat dome as bad as 1936.  JULY 2-4 that year Mt Pocono hit 98 99 and 103 on consecutive days and since then has never been higher than 95. I thought that might have been some instrument error but Boston recorded their all time high of 104 during that same torrid stretch.

Heat domes aren't new. But the warming background climate has made even relatively ordinary heat domes much hotter than they were decades ago. Regional patterns coupled with a wetter climate has likely contributed to the recent absence of long-duration heatwaves in parts of the Northeast. 

[rclab]

7 hours ago, LibertyBell said:

Climate change affects different places differently which is why I like this term better than global warming. For this region the warming is more in the winter.  This isn't just about 1936 either or even Central Park bad siting. 1966 still holds the heat records for both LGA and JFK 107 and 104. I'd argue that 107 at LGA from July 1966 is more impressive than the 108 at Newark from July 2011. And big heat domes aren't a new thing, 1980, 1983, 1988, 1991, 1993, 1995, 1999 and 2002 had plenty of them. It's why I consider the 1980s and 1990s to be hotter especially ranked by duration of heat waves and number of 100 degree days. 1993 is still untouched in that regard.

We can even go back to 1911 to see a heat dome as bad as 1936.  JULY 2-4 that year Mt Pocono hit 98 99 and 103 on consecutive days and since then has never been higher than 95. I thought that might have been some instrument error but Boston recorded their all time high of 104 during that same torrid stretch.

I was hoping to read a post from you again before I transition. Stay well, you’re already blessed. As always …..

 

[GaWx]

Opinions about this, which shows lowest cumulative YTD burnt area as of July 1st in Americas since at least 2012?@donsutherland1@WolfStock1

[donsutherland1]

1 hour ago, GaWx said:

Opinions about this, which shows lowest cumulative YTD burnt area as of July 1st in Americas since at least 2012?@donsutherland1@WolfStock1

The map is dated. Nevertheless, winter fire activity in South America has so far been largely suppressed by a wetter to much wetter than normal start to winter. The U.S. has seen a fairly sizable pickup in fire activity in late July. 

[GaWx]

1 hour ago, donsutherland1 said:

The map is dated. Nevertheless, winter fire activity in South America has so far been largely suppressed by a wetter to much wetter than normal start to winter. The U.S. has seen a fairly sizable pickup in fire activity in late July. 

Yeah, Don, I just looked at the following, which is as of Aug 1. It tells me that whereas Aug 1st is NN for NA, SA is MBN. Projecting from Aug 1 to EOY gets NA to ~2012-25 avg but SA is headed for MBN when projected.

 July added only ~4 mill ha in Americas vs avg of ~8 due to wet SA thus putting Aug 1st even further behind than Jul 1st:

[donsutherland1]

Denver has quietly reached and then surpassed 40 90° or above days. What was once an uncommon event has now become routine in the warming climate. Through August 2, 2026, Denver has had 41 such days. During 1872-1999, Denver saw 40 or more such days about once every 7.5 years. Since 2000, such years have occurred once every 1.2 years. Eleven of the last 12 years have seen 40 or more such days.

 

[GaWx]

 I just found an up to date (July 29th) source of worldwide burnt acreage in 2026 vs 2012-25:

 I don’t want to minimize how terrible these fires are wherever they occur and also I realize there’s CC contribution to these though it’s pretty complex. However, it just so happens that the two lowest years of year to date burnt world acreage since 2012 as of week 30 (~July 29th) are none other than 2026 (lowest with 112 million ha) and 2025 (2nd lowest with 131). The remainder are way up at 162-216. The avg of 2012-25 is 193. Thus, 2026 is a whopping 81 million ha below the 2012-25 week 30 world avg!

 I’m guessing it’s probably caused largely by more favorable wx (some combo of wetter (like in S America) as well as fewer lightning strikes, lower temps, and/or lighter winds in dry areas), fewer arsonists, and/or better firefighting:

 

@donsutherland1@WolfStock1

[LibertyBell]

On 8/1/2026 at 8:09 AM, donsutherland1 said:

Heat domes aren't new. But the warming background climate has made even relatively ordinary heat domes much hotter than they were decades ago. Regional patterns coupled with a wetter climate has likely contributed to the recent absence of long-duration heatwaves in parts of the Northeast. 

Don't look at these crazy records from 1911 103 at Mt Pocono is a sea level adjusted equivalent temperature of 114!! Outside of those 3 days in 1911 Mt Pocono hasn't been hotter than 95!! Five of the top ten are from 1911 including one in May! What was happening that year?

In that same torrid stretch Newark hit 103 and Boston hit their all time high of 104 and it even topped 100 in the Green and White Mountains!!

https://recordtemps.in/mount-pocono-pennsylvania

[LibertyBell]

4 hours ago, donsutherland1 said:

Denver has quietly reached and then surpassed 40 90° or above days. What was once an uncommon event has now become routine in the warming climate. Through August 2, 2026, Denver has had 41 such days. During 1872-1999, Denver saw 40 or more such days about once every 7.5 years. Since 2000, such years have occurred once every 1.2 years. Eleven of the last 12 years have seen 40 or more such days.

 

I think we will see that kind of summer here next year although our rate of 90 degree temperatures is not rising anywhere nearly as quickly.