Precipitation falling as rain instead of snow has implications not only for flooding but for the water cycle. Ecosystems and agriculture will be affected in the region if there's less water in the summer due to less snowpack accumulating in the winter.
Absolutely! Ecosystems, including human systems, are adapted to the seasonal cycle in runoff. As it changes due to climate change, this will cause problems.
Yes. It can be hard to get the the idea across that climate change may have multiple impacts on local water cycles, even if total annual precipitation doesn't change. The shift from snow to rain, warmer temperatures drawing soil moisture down faster in the growing season, fire season arriving early and formerly perennial streams dewatering in the dry season, all have impacts depending on where you are in the ecosystem.
For the victims of the PNW floods, climate change means the water rose higher than historic floods, fractionally attributable to the atmosphere dumping more rain on their heads in a shorter time than it has before, because it's warmer. The costs are being described as "catastrophic", even if the usual suspects will snicker "CAGW". Humans may "adapt" to heavier rains, higher floods, and hotter dryer summers, but at what cost? And what of the non-human biota? The sooner global fossil carbon emissions are capped, the lower subsequent high waters will be. Collective decarbonization at the national level seems like a "no-brainer" to me.
A further problem is that most people don't realize how a change on the margins can have a big impact, whether rainfall amounts, gasoline consumption, a degree higher on a hot day driving grid demand spikes, that last tequila shot....
This is another reason that water managers have to shift to more opportunistic than seasonal water capture approaches, relying more on the erratic wet *years* rather than wet *seasons*. There is a long overdue effort in California's Central valley to add aquifer recharge zones that hold water longer, allowing more to enter the overdrawn aquifers.
Les exploiteurs trouvent ça positif que les grandes glaces du nord fondent; Ils disent que ça libère des passages pour leurs cargos. Ils placent leur profits avant l'avenir de leurs enfants.
What, exactly, is the significance of this argument? Taking as a given that there is a trend in PNW floods, because the physics says it must be so, you also say that the trend is much smaller than year to year variability.
If there's a policy implication, the implication is that the PNW must be prepared to deal with the variability. The resulting questions would include
* How often are flood control measures overwhelmed?
* Are flood control measures less adequate now than they were 50 or 100 years ago?
* How much would it cost to improve flood control measures?
* What would be the benefit of improving flood control measures?
* Are floods more (or less) damaging because there is more (or less) property (and people) in the path of floods?
I'm sure these questions are probably outside the wheelhouse of climate scientists, but they seem much more relevant than theoretical arguments about undetectable trends.
Good to hear from you, Brian. I haven’t seen any comments from you and was worried something happened to you.
To answer your question, you should adopt a climate risk framework. We know the hazard is getting worse (this is what my post covers), but you’re right that you need to evaluate the exposure and vulnerability of the systems of interest to get the total impacts on humans.
Thanks for the reply. I hope we're not talking past each other. Your earlier column focused on "Why are climate impacts escalating?" without establishing that climate impacts are escalating. This seems like a variation on the theme.
As you noted, it can take a long time and lot of data to clearly show a trend in a data series with a lot of variability. It shouldn't be too hard to show how much risk our current system has. I know that's not your topic, but it seems a lot more interesting.
You imply (but don't clearly claim) that flooding in the Pacific Northwest is worse than the norm. That may be true. You imply (but don't clearly state) that floods are noticeably more damaging than the norm. That may also be true.
Whether these are true or not, it may be that better flood control measures are needed. It could be that flood control measures have been inadequate for decades. It could be that current flood control measures are more than adequate for the worst recent flooding.
Yeah, once it has been established rain rates and quantities are going up in a specific area, I wouldn't go to any climate scientist with a question about the quality of a specific flood control measures there. We need to find out what budget and labor (that hasn't been deported) and political impacts to upgrade and maintain flood control measures.
I come from a family of engineers and infrastructure nerds. Climate scientists have pretty much described the range of changes we'll be facing, and it's up to local experts and civil engineers and budgeteers to take up the baton, just as we must know the physical requirements of an industrial process pipe, but have to go to builders and vendors to cost out and design and implement the systems.
When climate scientists are on mainstream media, the interviewers often ask them questions about adaptation or possible mitigation. Those interviewers should be making the transition to interviewing civil engineers, water managers, etc., who have practical knowledge about what is possible and what things cost. Why the hell should a reporter think that, say, Michael Mann has any idea about sea defenses or firefighting?
A partnership would actually be beneficial to all concerned. When providing information to the audience is the goal of media, having the dual voices of cause and effect, presenting a linear picture reaches a higher level of acceptance of the problem.
It's part of the *job* of reporters to bring in the appropriate expertise. Climate scientists are already stepping out by becoming science explainers.(It really entails learning a whole different skill set in communicating to the public; Michael Mann no longer has that deer-in-the-headlights look.)
A climate change *organization* (like one of Bill McKibben's projects) could provide and groom infrastructure experts to provide descriptions of how much more sea walls cost per extra meter of height, why old gravity-based storm water systems don't work any more, the competition for construction and materials, etc.
Interesting here is your criticism of the IPCC's conceptualization of detection of change (statistical), which follows directly from the IPCC's definition of "climate change."
Detection of change is indeed challenging, not because of "climate misinformers" (like the IPCC?) but because detecting a change in climate is difficult, given modes of variability. Detection of change a la IPCC is _supposed_ to be difficult.
In your example use median streamflow (which is sound), but had you used peak streamflow (more aligned with flooding) it'd be even more difficult to detect significant trends given variability. If you set aside statistical significance in your example, then ~84% of your 1000 realizations would show an increasing linear trend. At the same time, in a time series with no imposed change 50% of realizations will show an increase.
The IPCC argues that detection of change should be made >90% liklihood/confidence.
Detecting a trend is not the same as attribution, and flooding is particularly complex, see this excellent new paper on the many causes of flood trends (or lack thereof):
That complexity of course is why the IPCC has done what it has done.
The reality of climate variability (and other human changes to flood regimes) establishes a high bar for detecting a change in climate in streamflows.
That is also why the IPCC has not claimed to have achieved detection of changes in flooding, much less attribution -- even at the global level.
So if you want to take on the IPCC you should be less subtle ;-)
PS. Lest there be any doubt, humans affect the climate system through the emission of CO2 (and other pathways) and decarbonization of the global economy makes good sense.
I don’t disagree that detecting flood trends is statistically difficult or that the IPCC sets a high bar. But local detection is possible in some regions, and more importantly, failure to meet global detection thresholds shouldn’t be interpreted as evidence that climate change isn’t increasing flood risk — which the IPCC explicitly says it is.
"In summary, the seasonality of floods has changed in cold regions where snowmelt dominates the flow regime in response to warming (high confidence). There is low confidence about peak flow trends over past decades on the global scale , but there are regions experiencing increases, including parts of Asia, Southern South America, north-east USA, north-western Europe, and the Amazon, and regions experiencing decreases, including parts of the Mediterranean, Australia, Africa, and south-western USA."
"In summary, there is medium confidence that simulations for the most extreme flows by regional hydrological models can have large biases. Global-scale hydrological models still struggle with reproducing the magnitude of floods. Projections of future floods are hampered by these difficulties and cascading uncertainties, including uncertainties in emissions scenarios and the climate models that generate inputs."
"In summary there is low confidence in the human influence on the changes in high river flows on the global scale. In general, there is low confidence in attributing changes in the probability or magnitude of flood events to human influence because of a limited number of studies, differences in the results of these studies and large modelling uncertainties."
The IPCC is an assessment not a bible, so of course no one need concur with these provisional conclusions. But the IPCC has clearly not claimed to have achieved detection or attribution related to trends in flooding. The IPCC is also very clear that changes in precipitation, for which detection and attribution have been achieved, cannot be used as a proxy for trends in flooding.
Climate change is not a cause, it is a change in the state of the climate that can be identified (e.g., by using statistical tests) by changes in the mean and/or the variability of its properties and that persists for an extended period, typically decades or longer.
If you are asking whether we can meaningfully quantify the effects of accumulating carbon dioxide in the atmosphere on damage from this specific event, the answer is no, we cannot. Of course, some have proposed methods for such quantification (i.e., extreme event attribution), I think these approaches are pretty much meaningless (as I've explained in detail over at THB and won't repeat here). I stick to the IPCC's conventional framework for detection and attribution of change.
If you want to detect changes in climate, look at climate data, not damage data.
However, with climate data in hand it is perfectly reasonable to see what effect detected changes might have had on outcomes we care about, like flood damage. We looked at exactly this question in a paper 25 years ago, one of my favorites:
Pielke Jr, R. A., & Downton, M. W. (2000). Precipitation and damaging floods: Trends in the United States, 1932–97. Journal of Climate, 13(20), 3625-3637.
Figure 2 in that paper shows why it is nigh impossible to tease out a meaningful signal of human-caused changes in climate in damage data.
Table 6 shows that the Northwest had the strongest correlation (among regions) between a measure of precipitation (EXT, number of days >2" precip) and overall damage and damage per capita.
However, given that "Washington has not experienced any long-term trend in the number of extreme precipitation events" [specifically >2"], there is no empirical basis to even hypothesize that increasing extreme precipitation events have led to an increase in damage.
Downton, M. W., Miller, J. Z. B., & Pielke Jr, R. A. (2005). Reanalysis of US National Weather Service flood loss database. Natural Hazards Review, 6(1), 13-22.
Overall, US flood damage has decreased by ~80% since the 1940s when normalized by GDP, meaning that any small signal in damage of a change in climate (whatever the cause) would be incredibly difficult to detect as the social factors that lead to damage are an order or two magnitudes larger.
But this chain of causality fails empirically at each step in your specific example:
1. In Washington, there is not an upwards trend in rainfall events most correlated with damage (linked above)
2. There has similarly not been a trend of greater flooding
See 1930-2014 in Figure 5 here:
Mastin, M. C., Konrad, C. P., Veilleux, A. G., & Tecca, A. E. (2016). Magnitude, Frequency, and Trends of Floods at Gaged and Ungaged Sites in Washington, based on data through water year 2014 (USGS SIR 2016–5118).
3. Thus, any increase in damage must be due to factors other than increases in rainfall or streamflow
[Note: None of this should be interpreted as saying that humans do not affect the climate system or to be contrary to the fact that increasing precipitation has been detected and attributed in other regions, a la IPCC.]
It is perfectly reasonable to want to connect changes in climate with disaster losses. I have explained with a flowchart how this much be done rigorously:
Just to be clear, I don’t think I’ve said anything you’re pushing back on. I agree that detecting flood trends is statistically difficult and that the IPCC sets a high bar for both detection and attribution. I also agree the IPCC has not claimed global-scale detection or attribution of flood trends.
My point is narrower: local and regional detection is possible in some places (as WG1 explicitly notes), and failure to meet global detection thresholds should not be interpreted as evidence that climate change is not increasing flood risk, which the IPCC does explicitly conclude. That’s a distinction between detection, attribution, and risk — not a disagreement with the IPCC.
This may be a bit nit-picky, but because the events being modeled are rare shouldn't Poisson or logPoisson distributions be used in calculations rather than the lognormal distribution?
If you want to model flood events, then I think you’re right. What I was simulating was river discharge rate. In any event, the answer you get is the same. I’ve done the same calculation for landfalling hurricanes using Poisson and you get the same answer: it’s hard to identify a trend.
Yes and... Surely CO2-driven climate change is affecting potential rainfall amounts in any storm or atmospheric river and the snow > rain trend in mountains (as I wrote in 1988 - downloadable here: https://revkin.substack.com/i/133815497/the-warming-view-from - drawing on Peter Gleick's work). The and is that the plumbing was broken in key flooding regions of the Pacific Northwest generations ago - with a lake turned into a "prairie" and farms and towns built on land that historically was under water. Described neatly in Tyree: https://thetyee.ca/Analysis/2021/11/18/Mapping-Abbotsford-Flood/
Mr. Revkin, your commitment to balance is journalistic by training, and seems sincere. Yet as you well know, *false* balance is down that same slippery slope, and is a popular rhetorical tactic of professional disinformers on behalf of fossil carbon producers and investors: see, for example, "The epistemic dangers of journalistic balance" (https://www.cambridge.org/core/journals/episteme/article/epistemic-dangers-of-journalistic-balance/BE1300ED448BAE016576E07AC0C237EE). Presumably that's why your former employer, the New York Times, has largely abandoned its historical straining for 'balance' with respect to the consensus of international climate science for anthropogenic global warming. That's unless you have insider information?
In any case, it's true as stated, that the total cost of the latest floods is partially attributable to large-scale anthropogenic changes to the watersheds. Indeed, Dr. Dessler ends his OP with:
'Note that this simple physical argument won’t tell you how much of the trend is due to climate change—that will require additional analysis. But for the question “Is climate change having an effect,” we can answer, “Almost certainly yes.”'
This is a substack about climate change (https://www.theclimatebrink.com/about), and its authors are at pains to explain why attribution of the cost of fossil-carbon-enhanced flooding, in money and tragedy, is always partial. Their purpose is to push back on for-profit and volunteer decarbonization obstructionism with well-supported science. Please, let's have no *misleading* balance here!
Nothing I wrote - not one word - is about false balance. It's about keeping an eye on all drivers of climate-related risk (the hazard, exposure and vulnerability). That is essential in figuring out how to reduce risk and loss going forward - how to avoid the "brink" that Andrew and Zeke have included in the name of this project. I've been writing about the seriousness of CO2-driven climate change since 1988, since before there was an IPCC. But a clear view of that science also includes understanding that it'd take decades for an impossible Paris track for emissions to measurably modulate rainfall or heat or storm behavior in ways that would cut harms. And that's why I wrote "YES AND..." Cut CO2 for long-term risk reduction and cut exposure and vulnerability for realtime risk reduction. Lots more here: https://revkin.substack.com/p/dont-fall-into-the-binary-emissions?utm_source=publication-search
Aye, part of the danger of climate change is all of the vulnerable human activity that we've been getting away with, like building on mountainsides or on landfill, or putting off infrastructure maintenance, or allowing political rationalizations about physical systems (e.g., making a special allowance that this new subdivision can attach to our barely adequate water supply). To steal a phrase, it's a →threat multiplier←. If anything, acknowledging all of the iffy development we've done in the past is *more* reason to worry about the effects of climate change and sea level rise.
[Personally, I've always objected when people use South Louisiana in discussions of climate change since we've long known about other major contributing effects of land loss: Starvation of sediment via constraining levees on the big rivers, and allowing corporations to cut more canals through the swamps. There are plenty of better examples to use, like the many places that would have been just fine without AGW.]
Just to be clear, I'm not trying to make a living here. I'm trying to help people widen their views of climate and energy challenges and choices (and disaster risk/resilience more generally). Money is no longer a driver of my webcasting and writing. We are fortunate to own our modest Maine home, have kids who are doing okay and enough to help my 93 year old mother in law have a good final run. So what I say here is a function of what I've learned, and unlearned, in 40 years on the climate (and wider risk) beat. Nothing more. Still wide open to others' insights as well.
Why are people who do trend analysis "climate misinformers"? Why do you need to delegitimize them so much? I would think that both types of analyses have their purposes. For me, it undermines your whole argument.
Trend analysis can be quite useful, when done right.
It's the *abused* and misused trend analysis that is problematic, like p-hacking, iffy meta-analyses, cherry picking, poor underlying data, insufficient sample sizes, and so forth.
With statistics it is critically important to know which tools work in which circumstances, and what are the most commonplace analytical fallacies for certain kinds of problems and data sets.
I'm guessing Prof. Dessler's argument was already undermined for you by disinformation. He just got through explaining that there are legitimate and illegitimate ways to do trend analysis. Refusal to adjust statistical methods for rare events delegitimizes itself, by reaching inaccurate conclusions!
If you're actually new to the climate-change information wars, you may not know that complaints about being delegitimized are popular with disinformationists. So is "tone trolling". They're not legitimate tactics either! See "Disinformation as an obstructionist strategy in climate change mitigation: a review of the scientific literature for a systemic understanding of the phenomenon" (https://open-research-europe.ec.europa.eu/articles/4-169/v2).
You speak exactly like all science disasters. You question tells the world that you have no idea, no clue what you're talking about. What you imagine is clever, Is Not.
My big question is: "Why is albedo such a non-understood word as Earth heats up?". Everything is ghg fossils deforestation.. all super important.. but carbon sinks and ice caps have no chance unless we reflect now too. Drawdown will fail without preserving the sinks.
Aren't the atmospheric rivers a manifestation of something other than sponge capacity? I got the impression (for which I'll blame Daniel Swain) that the warmer sea is filling the sponges faster and the modified jet stream is pulling more sponges across the landscape. (Basically, that it's a triple threat.)
Good question. Apparently the Pineapple Express is tropical air entrained by extratropical cyclones in the N. Pacific. I asked Google's Gemini GPT how climate change is affecting the phenomenon. It said, in part:
"Climate change is intensifying the Pineapple Express—a specific type of Pacific atmospheric river (AR) originating near Hawaii—by increasing its moisture capacity and altering its precipitation phase."
[FWIW, I wasn't saying that sponge capacity wasn't an effect—as it obviously is—but that there are *additional* AGW-related factors that can embiggen atmospheric rivers, like warmer ocean and wackadoodle jet streams.]
Heh. It won't take you long to reach the limits of any current GPT's credibility. You still have to ask for, and follow up on, its sources. Last week, ChatGPT confidently told me that RFK Jr. wasn't employed by any federal agency, and my links to contrary information on HHS.gov were fake! It turned out ChatGPT wasn't allowed to access the Internet for me without a paid account, and was relying on a year-old cached copy of the agency's website. I, for one, am disinclined to pay more for *correct* answers. I'm severely underwhelmed by the free samples!
Very clear demonstration of the difficulty of analysing trends in rare events. We see those "no statistical trend" denialist arguments a lot. In my relative statistical ignorance: does a Bayesian approach help capture trends predicted by physics, that frequentist methods don't show?
This event is perfectly within historical norms. The over attribution of every notable weather event to climate change has killed the credibility of the cause. Shame on all of you hyperbolics out there.
Portland, OR (Willamette River)
• 1861 (The Great Flood): ~33.0 feet
• 1894 (Columbia Backwater): 33.6 feet
• 1964 (Christmas Flood): 30.0 feet
• 1996 (February Flood): 28.6 feet
• 2025 (Atmospheric River): 27.9 feet (Managed by dams)
The issue is not whether climate change is having an effect. The issue is whether the effect is so material that it justifies a significant change in policy. An admission that there is uncertainty there from some of the climate change advocates would be helpful.
I'd say this is clearly impactful enough be prudent and act.
----------------------------------------
"As the Earth moved out of ice ages over the past million years, the global temperature rose a total of 4 to 7 degrees Celsius over about 5,000 years.
In the past century alone, the temperature has climbed 0.7 degrees Celsius, roughly TEN TIMES FASTER than the average rate of ice-age-recovery warming."
NASA Earth Observatory
---------------------------
That is from 2010. The warming since 1880 is now about double the 0.7C warming NASA was referring to.
True for the federal government but not for many states that have emission pledges that were always highly ambitious. It is worth discussing whether they make sense.
Hurricane strengths are increasing and so is the rate that they intensify.
Wildfires are increasing in intensity an acreage burned; and forget the common denier rant about historical fires. There were no national large scale fire fighting abilities before about the 1930s, so they just went on burning acreage. And fire reports are known to have been redundant, different agencies reporting the same fires back then.
Farmers are already having problems in many parts of the world, from higher temps, drier soils, flooding, etc. Very heavy downpours of precipitation are increasing. The floods this week in Washington state are not just because of the heavy rainfall, but also because there is no more rain and less snow in winter, the runoff overwhelming rivers and streams.
Many places are seeing whiplashes between flooding and drought, Texas for example. Even when there is no drought, the warmer atmosphere is thirsty, sucking moisture out of soils and plants. Ironically the warmer atmosphere that can hold more moisture is causing both that and heavier rain and snow storms.
Because of warmer, shorter winters, pine bark beetle populations have been exploding. They are devastating conifer forests, killing hundreds of millions if not billions of trees. That adds dead trees to the wildfire fuel load. This is happening all across the U.S. West and up into Southwest Canada.
Galveston already has about 1 foot of sea level rise, half from land sinking and half from sea level rise since 1900. It's likely to have ~2 feet combined rise by 2050. The largest loss of life in an natural disaster in American history was 6,000 dead in Galveston when a hurricane hit in 1906.
ALL these things and much more are happening. But of course deniers always have the "it's happened before" response, conveniently ignoring that they have not all happened at the same time. To have all this happening this early in the game is indeed SCARY. I've only mentioned a few of many observed changes.
Coral reefs are bleaching and dying worldwide from warmer oceans; and are also under attack from ocean acidification. Acidification also is really bad news for all shelled marine life, not to mention other creatures that feed on them.
9 Category 4 or 5 hurricanes in the Atlantic Basin in the last 8 years, 8 of which made landfall in the U.S.
8 Category 4 or 5 hurricanes in the Atlantic Basin in the previous 57 years.
-------------------
The Global Climate 2011-2020: Sea Ice
"There has also been a marked decrease in the extent of ice which lasted for more than one year. In March 1985, old ice (four years or more) accounted for 33% of the total ice cover of the Arctic Ocean, but that figure had fallen below 10% by 2010, and in March 2020 it had dropped to 4.4%. Ice of this age is now mostly confined to a narrow strip extending from north of Greenland along the north-west edge of the Canadian archipelago."
World Meteorology Organization WMO
----------------------------------
Phoenix, Arizona
70 days over 110F in 2024
That surpassed the previous record of 55 days set in 2023. In the early 1900s, the average was only five days per year at or above 110°F, and by the 2010s, it had increased to 27 days annually.
Tampa Florida - 60 days 90F or more in the 1970s
120 days 90F or more in the 2020s.
----------------------
Siberia wildfires
"The 2021 fire season was Russia's largest ever, with 18.8 million hectares (46.5 million acres) of forest destroyed, according to Greenpeace Russia – about two times the size of the island of Ireland.
In 2003, a series of wildfires in the taiga forests of Eastern Siberia burned over 55 million acres (22 million hectares) of land, making them some of the most devastating and largest wildfires in human history.
In 2022, wildfires in Siberia burned a significant area, with over 3.2 million hectares (approximately 7.9 million acres) affected. This included fires in both Siberian and Far East regions, with the Khabarovsk region in the Far East experiencing a large concentration of blazes.
in July 2019 in areas difficult to access in northern Krasnoyarsk Krai, the Sakha Republic and Zabaykalsky Krai, all of which are within Russia’s Siberian Province. By the end of that month the size of the fires had reached 2.6 million hectares (ha) (6.4 million acres). According to Russian News Agency TASS quoting the Krasnoyarsk Forest Fire Center, the causes of forest fires are natural due to 30-degree Celsius heat (86 degrees Fahrenheit), gusts of wind and dry thunderstorms."
NASA
2020
"Burned area and number of fires in Siberia from March through September 2020, distributed by latitudinal bands. Total burned area for Siberia in 2020 was 25.5 million ha, in almost 15,000 individual fires." International Association of Wildland Fires
25.5 hectares = 62.98 million acres burned
-----------------
6/14/24
Firefighters are battling wildfires in Brazil's Pantanal, the world's largest tropical wetland.
1.7 million acres burned.
In 2020, a huge wildfire struck the Brazilian Pantanal – the largest tropical wetland area in the world. Driven by extreme drought, high temperatures and human activities, the blaze cut through more than 44,515km² (16,916 Sq. miles or 130x130 miles) of habitat and killed an estimated 17 million vertebrates.
-----------
Canadian wildfires 2023
Based on data in the National Forestry Database, over 8000 fires occur each year, and burn an average of over 2.1 million hectares, or about 5 million acres.
2023 fires totaled 37.71 million acres as of Aug. 22. or 59,000 square miles
SEVEN Times larger area than average
The total was 47 million acres for the year.
The temperature was 101F at a town in the Yukon; and 121F at a town in Southwest Canada. That town subsequently burned to the ground.
Death Valley temperatures in Canada!
And in the beginning of June 2025 there were already 5 million acres burned, which is the average Annual number, and summer hadn't even started yet.
8/3/2025
In 2025, Canadian wildfires have burned over 13.6 million acres (5.5 million hectares).
Is losing your community to accelerated sea level rise a catastrophe?
How about increasing the chance of a major problem from one in twenty years to one in ten years, like flood, river too low to transport goods, crop-destroying drought, coral bleaching, subway system flood, etc. (Consult your insurance actuary for the premiums on those.)
Is losing a municipal well to salt water intrusion a catastrophe?
Is the collapse of a local fishery a catastrophe?
Is the →increase← in power and rapid intensification of tropical cyclones a catastrophe?
If you don't think those are catastrophes, I can understand why you focus so much on the term "catastrophe" rather than on accelerated economic collapse, accelerated loss of living space, poorer crop yields, increased aridification, etc.
I'm happy you're living in some sort of climate haven where you won't lose your shelter, your food supply or your income from the land, and your power supply is not reliant on a grid vulnerable to ice storms, wildfires, or windstorms.
Scott has been asked many times, here and elsewhere, for his definition of catastrophe. I've never seen him answer the question. I think it's because he doesn't want to expose his lack of empathy for the victims of catastrophic climate change to date. So let me put it into words for him: if neither he nor anyone he cares about is a casualty, it's not a catastrophe!
It's true "catastrophe" is not scientifically defined. Nonetheless, it's appearing more and more often in peer-reviewed scientific reports and analyses of anthropogenic climate change. Scott and his fellow obstructionists here will demand a citation, so here's a Nature report on "The unprecedented Pacific Northwest heatwave of June 2021" (https://www.nature.com/articles/s41467-023-36289-3). The abstract states:
"The impacts of this event were catastrophic, including hundreds of attributable deaths across the Pacific Northwest, mass-mortalities of marine life, reduced crop and fruit yields, river flooding from rapid snow and glacier melt, and a substantial increase in wildfires—the latter contributing to landslides in the months following. These impacts provide examples we can learn from and a vivid depiction of how climate change can be so devastating."
I personally survived the personally-unprecedented event in my personal heat-pump-cooled house, hoping the power stayed on (it did, thank you). But that's merely anecdotal. And Scott can no doubt find fault with any peer-reviewed empirical report. Earnest climate realists are hereby advised: don't waste too much time crafting careful replies, you'll just be repeating yourself. He's a tar baby!
I'm not a climate change advocate (I'm against it), but there's plenty of acknowledgments of uncertainty CLEARLY DISPLAYED ON GRAPHS all over this bloody conversation. The uncertainty isn't about whether the climate is changing (it is) or sea level is rising (it is) or that polar ice is melting (it is) or that glaciers are rapidly disappearing (they are), or that heat and drought are lowering crop yields (they are), or that coral reefs worldwide—"the nurseries of the sea"—are dying at a rapid rate (they are), or that tropical cyclones are more rapidly intensifying as the world warms (physics, baby!), but how fast and by how much faster as we go along.
It's clear that you don't live on the coast of Bangladesh, or within sight of alpine glaciers, or in the parts of the world that are reaching deadly wet-bulb temperatures. You're not a fisherman in the rapidly warming Gulf of Maine, or an outdoor laborer, or the mayor of a doomed coastal town, or a wildfire fighter, or a municipal engineer that has to deal with higher and higher tides affecting a major coastal city, or a doctor that is familiar with heat stroke victims in the ER, or a resident of a town that got hit by its first Cat 5 cyclone in its centuries-old history.
So what *is* your background, that you are unaware of how bad even the best-case-scenario impacts are?
The three major factors that cause measurable coral declines along the GBR are
- storm damage (very erratic over time)
- freshwater intrusion (local major flood runoff events)
- ocean heating (variable but climbing)
The most critical issue is the increasing ocean heat. Individual bleaching events are related to local marine heat waves. As on land, regional sea temperatures are not monotonically increasing, but increasing generally (except for the North Atlantic cold blob, which models predicted would be anomalous, but even that will eventually warm up). The GBR may have the added protection that adjacent sectors can "re-seed" local damage to hard corals, but that doesn't solve the increasing heat problem.
GLOBALLY, coral bleaching events are becoming more frequent, and at some point individual coral reefs do not come back. (Death is a tipping point.) Local attempts—as in S. Florida—to "rescue" and breed more heat-resistant corals is yet another expensive attempt to mitigate the effects of ocean warming and protect our ocean food supply.
"An admission that there is uncertainty there from some of the climate change advocates would be helpful."
I'm not a "climate change advocate" (is anybody?), I'm an opponent of it. But I have no problem admitting there is uncertainty there. It's been quantified and passed peer review. Is that helpful?
You see those squiggly lines on the temperature graphs up to the current time? That's the observed data. You see the smoother lines in the future from the models? That's a [weighted] average. Do you see the shaded areas around the forecast temps, THAT'S THE QUANTIFIED RANGE OF FORECAST TEMPERATURE. (Amazingly enough, sea level graphs work much the same way!)
In case you aren't familiar with these concepts in reading graphs, I suggest
The precedent having been set, I too will resort to ALL CAPS for emphasis, shouty as it may be. Citations are for the lurkers, as it's clear Scott won't read them:
Scott: "That sounds scary! Where are the catastrophes that would go along with such a scary situation?"
Scott: "'There is no way, no how that you are going to convince me that we are living in "terrifying" times.'"
WE GET IT, SCOTT! Your own subjective judgement notwithstanding, growing numbers of others - survivors, scientists, journalists - are applying "catastrophic" to "scary situations" like the 2021 PNW heat dome, more category 5+ hurricanes at landfall, the surprise flash floods in Texas this summer, and now the global-warming-enhanced atmospheric river flooding Washington. ATTRIBUTABLE DEATHS TO DATE IN THE MILLIONS, ECONOMIC LOSSES IN THE $TRILLIONS, SCOTT! Lurkers: want peer-reviewed numbers? https://www.nature.com/articles/s41467-023-36289-3, https://www.nature.com/articles/s41467-023-41888-1, https://www.nature.com/articles/s41558-025-02399-7.
Scott: "Can't find them? Correct. They aren't there."
INCORRECT! They ARE there! You'll never find them, having ruled them out a priori. The rest of us can see them clearly, and imagine the MORTAL TERROR of the victims! SCARY ENOUGH FOR MOST OF US! WTF IS WRONG WITH YOU? NOW I'M JUST SHOUTING!
Whew! Somebody else take the mallet. Gotta pace myself. TCB needs a better class of obstructionist! RPJr is smart enough, at least.
Thumbs-up
Precipitation falling as rain instead of snow has implications not only for flooding but for the water cycle. Ecosystems and agriculture will be affected in the region if there's less water in the summer due to less snowpack accumulating in the winter.
Absolutely! Ecosystems, including human systems, are adapted to the seasonal cycle in runoff. As it changes due to climate change, this will cause problems.
Yes. It can be hard to get the the idea across that climate change may have multiple impacts on local water cycles, even if total annual precipitation doesn't change. The shift from snow to rain, warmer temperatures drawing soil moisture down faster in the growing season, fire season arriving early and formerly perennial streams dewatering in the dry season, all have impacts depending on where you are in the ecosystem.
For the victims of the PNW floods, climate change means the water rose higher than historic floods, fractionally attributable to the atmosphere dumping more rain on their heads in a shorter time than it has before, because it's warmer. The costs are being described as "catastrophic", even if the usual suspects will snicker "CAGW". Humans may "adapt" to heavier rains, higher floods, and hotter dryer summers, but at what cost? And what of the non-human biota? The sooner global fossil carbon emissions are capped, the lower subsequent high waters will be. Collective decarbonization at the national level seems like a "no-brainer" to me.
For most of those climate change minimizers, it's all remote and theoretical, like somebody else experiencing flooding.
A further problem is that most people don't realize how a change on the margins can have a big impact, whether rainfall amounts, gasoline consumption, a degree higher on a hot day driving grid demand spikes, that last tequila shot....
This is another reason that water managers have to shift to more opportunistic than seasonal water capture approaches, relying more on the erratic wet *years* rather than wet *seasons*. There is a long overdue effort in California's Central valley to add aquifer recharge zones that hold water longer, allowing more to enter the overdrawn aquifers.
Les exploiteurs trouvent ça positif que les grandes glaces du nord fondent; Ils disent que ça libère des passages pour leurs cargos. Ils placent leur profits avant l'avenir de leurs enfants.
Chateau Sous Les Mers I call Mar a Lago. It might make a nice reef if acidity and temps go gobin 50 years.
What, exactly, is the significance of this argument? Taking as a given that there is a trend in PNW floods, because the physics says it must be so, you also say that the trend is much smaller than year to year variability.
If there's a policy implication, the implication is that the PNW must be prepared to deal with the variability. The resulting questions would include
* How often are flood control measures overwhelmed?
* Are flood control measures less adequate now than they were 50 or 100 years ago?
* How much would it cost to improve flood control measures?
* What would be the benefit of improving flood control measures?
* Are floods more (or less) damaging because there is more (or less) property (and people) in the path of floods?
I'm sure these questions are probably outside the wheelhouse of climate scientists, but they seem much more relevant than theoretical arguments about undetectable trends.
Good to hear from you, Brian. I haven’t seen any comments from you and was worried something happened to you.
To answer your question, you should adopt a climate risk framework. We know the hazard is getting worse (this is what my post covers), but you’re right that you need to evaluate the exposure and vulnerability of the systems of interest to get the total impacts on humans.
To the extent that we are adapted to pre-climate variability, even small increases can push us past thresholds in the system. See this for explanation of how small changes can lead to big impacts: https://www.theclimatebrink.com/p/why-are-climate-impacts-escalating
Thanks for the reply. I hope we're not talking past each other. Your earlier column focused on "Why are climate impacts escalating?" without establishing that climate impacts are escalating. This seems like a variation on the theme.
As you noted, it can take a long time and lot of data to clearly show a trend in a data series with a lot of variability. It shouldn't be too hard to show how much risk our current system has. I know that's not your topic, but it seems a lot more interesting.
You imply (but don't clearly claim) that flooding in the Pacific Northwest is worse than the norm. That may be true. You imply (but don't clearly state) that floods are noticeably more damaging than the norm. That may also be true.
Whether these are true or not, it may be that better flood control measures are needed. It could be that flood control measures have been inadequate for decades. It could be that current flood control measures are more than adequate for the worst recent flooding.
Yeah, once it has been established rain rates and quantities are going up in a specific area, I wouldn't go to any climate scientist with a question about the quality of a specific flood control measures there. We need to find out what budget and labor (that hasn't been deported) and political impacts to upgrade and maintain flood control measures.
I come from a family of engineers and infrastructure nerds. Climate scientists have pretty much described the range of changes we'll be facing, and it's up to local experts and civil engineers and budgeteers to take up the baton, just as we must know the physical requirements of an industrial process pipe, but have to go to builders and vendors to cost out and design and implement the systems.
When climate scientists are on mainstream media, the interviewers often ask them questions about adaptation or possible mitigation. Those interviewers should be making the transition to interviewing civil engineers, water managers, etc., who have practical knowledge about what is possible and what things cost. Why the hell should a reporter think that, say, Michael Mann has any idea about sea defenses or firefighting?
A partnership would actually be beneficial to all concerned. When providing information to the audience is the goal of media, having the dual voices of cause and effect, presenting a linear picture reaches a higher level of acceptance of the problem.
It's part of the *job* of reporters to bring in the appropriate expertise. Climate scientists are already stepping out by becoming science explainers.(It really entails learning a whole different skill set in communicating to the public; Michael Mann no longer has that deer-in-the-headlights look.)
A climate change *organization* (like one of Bill McKibben's projects) could provide and groom infrastructure experts to provide descriptions of how much more sea walls cost per extra meter of height, why old gravity-based storm water systems don't work any more, the competition for construction and materials, etc.
Interesting here is your criticism of the IPCC's conceptualization of detection of change (statistical), which follows directly from the IPCC's definition of "climate change."
Detection of change is indeed challenging, not because of "climate misinformers" (like the IPCC?) but because detecting a change in climate is difficult, given modes of variability. Detection of change a la IPCC is _supposed_ to be difficult.
In your example use median streamflow (which is sound), but had you used peak streamflow (more aligned with flooding) it'd be even more difficult to detect significant trends given variability. If you set aside statistical significance in your example, then ~84% of your 1000 realizations would show an increasing linear trend. At the same time, in a time series with no imposed change 50% of realizations will show an increase.
The IPCC argues that detection of change should be made >90% liklihood/confidence.
Detecting a trend is not the same as attribution, and flooding is particularly complex, see this excellent new paper on the many causes of flood trends (or lack thereof):
https://www.nature.com/articles/s43017-025-00745-z
That complexity of course is why the IPCC has done what it has done.
The reality of climate variability (and other human changes to flood regimes) establishes a high bar for detecting a change in climate in streamflows.
That is also why the IPCC has not claimed to have achieved detection of changes in flooding, much less attribution -- even at the global level.
So if you want to take on the IPCC you should be less subtle ;-)
PS. Lest there be any doubt, humans affect the climate system through the emission of CO2 (and other pathways) and decarbonization of the global economy makes good sense.
I don’t disagree that detecting flood trends is statistically difficult or that the IPCC sets a high bar. But local detection is possible in some regions, and more importantly, failure to meet global detection thresholds shouldn’t be interpreted as evidence that climate change isn’t increasing flood risk — which the IPCC explicitly says it is.
Here is what the IPCC AR6 WG1 Ch.11 says:
"In summary, the seasonality of floods has changed in cold regions where snowmelt dominates the flow regime in response to warming (high confidence). There is low confidence about peak flow trends over past decades on the global scale , but there are regions experiencing increases, including parts of Asia, Southern South America, north-east USA, north-western Europe, and the Amazon, and regions experiencing decreases, including parts of the Mediterranean, Australia, Africa, and south-western USA."
"In summary, there is medium confidence that simulations for the most extreme flows by regional hydrological models can have large biases. Global-scale hydrological models still struggle with reproducing the magnitude of floods. Projections of future floods are hampered by these difficulties and cascading uncertainties, including uncertainties in emissions scenarios and the climate models that generate inputs."
"In summary there is low confidence in the human influence on the changes in high river flows on the global scale. In general, there is low confidence in attributing changes in the probability or magnitude of flood events to human influence because of a limited number of studies, differences in the results of these studies and large modelling uncertainties."
The IPCC is an assessment not a bible, so of course no one need concur with these provisional conclusions. But the IPCC has clearly not claimed to have achieved detection or attribution related to trends in flooding. The IPCC is also very clear that changes in precipitation, for which detection and attribution have been achieved, cannot be used as a proxy for trends in flooding.
I’m curious, Roger, what’s your opinion of whether climate change made THIS event more damaging?
Climate change is not a cause, it is a change in the state of the climate that can be identified (e.g., by using statistical tests) by changes in the mean and/or the variability of its properties and that persists for an extended period, typically decades or longer.
If you are asking whether we can meaningfully quantify the effects of accumulating carbon dioxide in the atmosphere on damage from this specific event, the answer is no, we cannot. Of course, some have proposed methods for such quantification (i.e., extreme event attribution), I think these approaches are pretty much meaningless (as I've explained in detail over at THB and won't repeat here). I stick to the IPCC's conventional framework for detection and attribution of change.
If you want to detect changes in climate, look at climate data, not damage data.
However, with climate data in hand it is perfectly reasonable to see what effect detected changes might have had on outcomes we care about, like flood damage. We looked at exactly this question in a paper 25 years ago, one of my favorites:
Pielke Jr, R. A., & Downton, M. W. (2000). Precipitation and damaging floods: Trends in the United States, 1932–97. Journal of Climate, 13(20), 3625-3637.
https://journals.ametsoc.org/view/journals/clim/13/20/1520-0442_2000_013_3625_padfti_2.0.co_2.xml
Figure 2 in that paper shows why it is nigh impossible to tease out a meaningful signal of human-caused changes in climate in damage data.
Table 6 shows that the Northwest had the strongest correlation (among regions) between a measure of precipitation (EXT, number of days >2" precip) and overall damage and damage per capita.
However, given that "Washington has not experienced any long-term trend in the number of extreme precipitation events" [specifically >2"], there is no empirical basis to even hypothesize that increasing extreme precipitation events have led to an increase in damage.
Source: https://statesummaries.ncics.org/chapter/wa/ [Figure 2d]
Washington flood damage is highly variable, see:
Downton, M. W., Miller, J. Z. B., & Pielke Jr, R. A. (2005). Reanalysis of US National Weather Service flood loss database. Natural Hazards Review, 6(1), 13-22.
Overall, US flood damage has decreased by ~80% since the 1940s when normalized by GDP, meaning that any small signal in damage of a change in climate (whatever the cause) would be incredibly difficult to detect as the social factors that lead to damage are an order or two magnitudes larger.
Bottom line:
Sure, you can hypothesize based on physics that:
accumulating CO2-->more intense rainfall events-->more flooding-->more damage
But this chain of causality fails empirically at each step in your specific example:
1. In Washington, there is not an upwards trend in rainfall events most correlated with damage (linked above)
2. There has similarly not been a trend of greater flooding
See 1930-2014 in Figure 5 here:
Mastin, M. C., Konrad, C. P., Veilleux, A. G., & Tecca, A. E. (2016). Magnitude, Frequency, and Trends of Floods at Gaged and Ungaged Sites in Washington, based on data through water year 2014 (USGS SIR 2016–5118).
3. Thus, any increase in damage must be due to factors other than increases in rainfall or streamflow
[Note: None of this should be interpreted as saying that humans do not affect the climate system or to be contrary to the fact that increasing precipitation has been detected and attributed in other regions, a la IPCC.]
It is perfectly reasonable to want to connect changes in climate with disaster losses. I have explained with a flowchart how this much be done rigorously:
https://rogerpielkejr.substack.com/p/how-would-we-know-if-disasters-are
Damages are simply a horrible place to look for signals of changes in climate. Use climate data.
Just to be clear, I don’t think I’ve said anything you’re pushing back on. I agree that detecting flood trends is statistically difficult and that the IPCC sets a high bar for both detection and attribution. I also agree the IPCC has not claimed global-scale detection or attribution of flood trends.
My point is narrower: local and regional detection is possible in some places (as WG1 explicitly notes), and failure to meet global detection thresholds should not be interpreted as evidence that climate change is not increasing flood risk, which the IPCC does explicitly conclude. That’s a distinction between detection, attribution, and risk — not a disagreement with the IPCC.
This may be a bit nit-picky, but because the events being modeled are rare shouldn't Poisson or logPoisson distributions be used in calculations rather than the lognormal distribution?
If you want to model flood events, then I think you’re right. What I was simulating was river discharge rate. In any event, the answer you get is the same. I’ve done the same calculation for landfalling hurricanes using Poisson and you get the same answer: it’s hard to identify a trend.
Is it beyond ironic that "Poisson" means "fish"?
Yes and... Surely CO2-driven climate change is affecting potential rainfall amounts in any storm or atmospheric river and the snow > rain trend in mountains (as I wrote in 1988 - downloadable here: https://revkin.substack.com/i/133815497/the-warming-view-from - drawing on Peter Gleick's work). The and is that the plumbing was broken in key flooding regions of the Pacific Northwest generations ago - with a lake turned into a "prairie" and farms and towns built on land that historically was under water. Described neatly in Tyree: https://thetyee.ca/Analysis/2021/11/18/Mapping-Abbotsford-Flood/
Mr. Revkin, your commitment to balance is journalistic by training, and seems sincere. Yet as you well know, *false* balance is down that same slippery slope, and is a popular rhetorical tactic of professional disinformers on behalf of fossil carbon producers and investors: see, for example, "The epistemic dangers of journalistic balance" (https://www.cambridge.org/core/journals/episteme/article/epistemic-dangers-of-journalistic-balance/BE1300ED448BAE016576E07AC0C237EE). Presumably that's why your former employer, the New York Times, has largely abandoned its historical straining for 'balance' with respect to the consensus of international climate science for anthropogenic global warming. That's unless you have insider information?
In any case, it's true as stated, that the total cost of the latest floods is partially attributable to large-scale anthropogenic changes to the watersheds. Indeed, Dr. Dessler ends his OP with:
'Note that this simple physical argument won’t tell you how much of the trend is due to climate change—that will require additional analysis. But for the question “Is climate change having an effect,” we can answer, “Almost certainly yes.”'
This is a substack about climate change (https://www.theclimatebrink.com/about), and its authors are at pains to explain why attribution of the cost of fossil-carbon-enhanced flooding, in money and tragedy, is always partial. Their purpose is to push back on for-profit and volunteer decarbonization obstructionism with well-supported science. Please, let's have no *misleading* balance here!
Nothing I wrote - not one word - is about false balance. It's about keeping an eye on all drivers of climate-related risk (the hazard, exposure and vulnerability). That is essential in figuring out how to reduce risk and loss going forward - how to avoid the "brink" that Andrew and Zeke have included in the name of this project. I've been writing about the seriousness of CO2-driven climate change since 1988, since before there was an IPCC. But a clear view of that science also includes understanding that it'd take decades for an impossible Paris track for emissions to measurably modulate rainfall or heat or storm behavior in ways that would cut harms. And that's why I wrote "YES AND..." Cut CO2 for long-term risk reduction and cut exposure and vulnerability for realtime risk reduction. Lots more here: https://revkin.substack.com/p/dont-fall-into-the-binary-emissions?utm_source=publication-search
Aye, part of the danger of climate change is all of the vulnerable human activity that we've been getting away with, like building on mountainsides or on landfill, or putting off infrastructure maintenance, or allowing political rationalizations about physical systems (e.g., making a special allowance that this new subdivision can attach to our barely adequate water supply). To steal a phrase, it's a →threat multiplier←. If anything, acknowledging all of the iffy development we've done in the past is *more* reason to worry about the effects of climate change and sea level rise.
[Personally, I've always objected when people use South Louisiana in discussions of climate change since we've long known about other major contributing effects of land loss: Starvation of sediment via constraining levees on the big rivers, and allowing corporations to cut more canals through the swamps. There are plenty of better examples to use, like the many places that would have been just fine without AGW.]
OK, Mr. Revkin! We're all entitled to your opinion ;^). I'm just glad I'm not trying to make a living off of mine!
Just to be clear, I'm not trying to make a living here. I'm trying to help people widen their views of climate and energy challenges and choices (and disaster risk/resilience more generally). Money is no longer a driver of my webcasting and writing. We are fortunate to own our modest Maine home, have kids who are doing okay and enough to help my 93 year old mother in law have a good final run. So what I say here is a function of what I've learned, and unlearned, in 40 years on the climate (and wider risk) beat. Nothing more. Still wide open to others' insights as well.
Why are people who do trend analysis "climate misinformers"? Why do you need to delegitimize them so much? I would think that both types of analyses have their purposes. For me, it undermines your whole argument.
Trend analysis can be quite useful, when done right.
It's the *abused* and misused trend analysis that is problematic, like p-hacking, iffy meta-analyses, cherry picking, poor underlying data, insufficient sample sizes, and so forth.
With statistics it is critically important to know which tools work in which circumstances, and what are the most commonplace analytical fallacies for certain kinds of problems and data sets.
Recommended reading for amateur trend analysts: "How to Lie with Statistics" by Darrell Huff (https://www.amazon.com/How-Lie-Statistics-Darrell-Huff/dp/0393310728). The author was an expert: a paid apologist for the tobacco industry (https://www.effortmark.co.uk/avoid-how-to-lie-with-statistics/).
I loved HTLWS, but never got the connection with his "thank you for smoking" role.
I'm guessing Prof. Dessler's argument was already undermined for you by disinformation. He just got through explaining that there are legitimate and illegitimate ways to do trend analysis. Refusal to adjust statistical methods for rare events delegitimizes itself, by reaching inaccurate conclusions!
If you're actually new to the climate-change information wars, you may not know that complaints about being delegitimized are popular with disinformationists. So is "tone trolling". They're not legitimate tactics either! See "Disinformation as an obstructionist strategy in climate change mitigation: a review of the scientific literature for a systemic understanding of the phenomenon" (https://open-research-europe.ec.europa.eu/articles/4-169/v2).
You should be more polite!
Nah.
You speak exactly like all science disasters. You question tells the world that you have no idea, no clue what you're talking about. What you imagine is clever, Is Not.
When will we REALLY reflect? Physically and mentally the only way to get on track to beat the heat beast.
Delphic!
The Oracle has his moments...
My big question is: "Why is albedo such a non-understood word as Earth heats up?". Everything is ghg fossils deforestation.. all super important.. but carbon sinks and ice caps have no chance unless we reflect now too. Drawdown will fail without preserving the sinks.
Aren't the atmospheric rivers a manifestation of something other than sponge capacity? I got the impression (for which I'll blame Daniel Swain) that the warmer sea is filling the sponges faster and the modified jet stream is pulling more sponges across the landscape. (Basically, that it's a triple threat.)
Good question. Apparently the Pineapple Express is tropical air entrained by extratropical cyclones in the N. Pacific. I asked Google's Gemini GPT how climate change is affecting the phenomenon. It said, in part:
"Climate change is intensifying the Pineapple Express—a specific type of Pacific atmospheric river (AR) originating near Hawaii—by increasing its moisture capacity and altering its precipitation phase."
Y'all can ask Gemini just as easily as I can ;^).
[FWIW, I wasn't saying that sponge capacity wasn't an effect—as it obviously is—but that there are *additional* AGW-related factors that can embiggen atmospheric rivers, like warmer ocean and wackadoodle jet streams.]
But I'm a-scared of Gemini!
(Also, I love blaming Daniel Swain for the mush in my head.)
"But I'm a-scared of Gemini!"
Heh. It won't take you long to reach the limits of any current GPT's credibility. You still have to ask for, and follow up on, its sources. Last week, ChatGPT confidently told me that RFK Jr. wasn't employed by any federal agency, and my links to contrary information on HHS.gov were fake! It turned out ChatGPT wasn't allowed to access the Internet for me without a paid account, and was relying on a year-old cached copy of the agency's website. I, for one, am disinclined to pay more for *correct* answers. I'm severely underwhelmed by the free samples!
Very clear demonstration of the difficulty of analysing trends in rare events. We see those "no statistical trend" denialist arguments a lot. In my relative statistical ignorance: does a Bayesian approach help capture trends predicted by physics, that frequentist methods don't show?
This event is perfectly within historical norms. The over attribution of every notable weather event to climate change has killed the credibility of the cause. Shame on all of you hyperbolics out there.
Portland, OR (Willamette River)
• 1861 (The Great Flood): ~33.0 feet
• 1894 (Columbia Backwater): 33.6 feet
• 1964 (Christmas Flood): 30.0 feet
• 1996 (February Flood): 28.6 feet
• 2025 (Atmospheric River): 27.9 feet (Managed by dams)
Mount Vernon, WA (Skagit River)
• 1906 (Old Record): 37.3 feet
• 1990 (Modern Record): 37.4 feet
• 2021 (Recent High): 36.9 feet
• 2025 (Current Record): 41.2 feet (Preliminary Peak)
The issue is not whether climate change is having an effect. The issue is whether the effect is so material that it justifies a significant change in policy. An admission that there is uncertainty there from some of the climate change advocates would be helpful.
I'd say this is clearly impactful enough be prudent and act.
----------------------------------------
"As the Earth moved out of ice ages over the past million years, the global temperature rose a total of 4 to 7 degrees Celsius over about 5,000 years.
In the past century alone, the temperature has climbed 0.7 degrees Celsius, roughly TEN TIMES FASTER than the average rate of ice-age-recovery warming."
NASA Earth Observatory
---------------------------
That is from 2010. The warming since 1880 is now about double the 0.7C warming NASA was referring to.
----------------------------------------------------------------------------------------
"The maximum rate of change in CO2 concentrations from the ice core records is around 100 ppm in 10,000 years, or around 1 ppm per century.
The current rate of change in CO2 concentrations is 1 ppm every 21 weeks."
NASA Climate Change
----------------------
That comes to 247 times faster CO2 increase now.
Totally agree that "it is prudent to act." But that doesn't mean that there can't be a debate over the degree of action required.
Maybe not, but right now the debate in the US is over some action vs. none, with "none" temporarily ascendant.
True for the federal government but not for many states that have emission pledges that were always highly ambitious. It is worth discussing whether they make sense.
FALSE
Hurricane strengths are increasing and so is the rate that they intensify.
Wildfires are increasing in intensity an acreage burned; and forget the common denier rant about historical fires. There were no national large scale fire fighting abilities before about the 1930s, so they just went on burning acreage. And fire reports are known to have been redundant, different agencies reporting the same fires back then.
Farmers are already having problems in many parts of the world, from higher temps, drier soils, flooding, etc. Very heavy downpours of precipitation are increasing. The floods this week in Washington state are not just because of the heavy rainfall, but also because there is no more rain and less snow in winter, the runoff overwhelming rivers and streams.
Many places are seeing whiplashes between flooding and drought, Texas for example. Even when there is no drought, the warmer atmosphere is thirsty, sucking moisture out of soils and plants. Ironically the warmer atmosphere that can hold more moisture is causing both that and heavier rain and snow storms.
Because of warmer, shorter winters, pine bark beetle populations have been exploding. They are devastating conifer forests, killing hundreds of millions if not billions of trees. That adds dead trees to the wildfire fuel load. This is happening all across the U.S. West and up into Southwest Canada.
Galveston already has about 1 foot of sea level rise, half from land sinking and half from sea level rise since 1900. It's likely to have ~2 feet combined rise by 2050. The largest loss of life in an natural disaster in American history was 6,000 dead in Galveston when a hurricane hit in 1906.
ALL these things and much more are happening. But of course deniers always have the "it's happened before" response, conveniently ignoring that they have not all happened at the same time. To have all this happening this early in the game is indeed SCARY. I've only mentioned a few of many observed changes.
Imagine what 3-5C warming will do.
Coral reefs are bleaching and dying worldwide from warmer oceans; and are also under attack from ocean acidification. Acidification also is really bad news for all shelled marine life, not to mention other creatures that feed on them.
9 Category 4 or 5 hurricanes in the Atlantic Basin in the last 8 years, 8 of which made landfall in the U.S.
8 Category 4 or 5 hurricanes in the Atlantic Basin in the previous 57 years.
-------------------
The Global Climate 2011-2020: Sea Ice
"There has also been a marked decrease in the extent of ice which lasted for more than one year. In March 1985, old ice (four years or more) accounted for 33% of the total ice cover of the Arctic Ocean, but that figure had fallen below 10% by 2010, and in March 2020 it had dropped to 4.4%. Ice of this age is now mostly confined to a narrow strip extending from north of Greenland along the north-west edge of the Canadian archipelago."
World Meteorology Organization WMO
----------------------------------
Phoenix, Arizona
70 days over 110F in 2024
That surpassed the previous record of 55 days set in 2023. In the early 1900s, the average was only five days per year at or above 110°F, and by the 2010s, it had increased to 27 days annually.
Tampa Florida - 60 days 90F or more in the 1970s
120 days 90F or more in the 2020s.
----------------------
Siberia wildfires
"The 2021 fire season was Russia's largest ever, with 18.8 million hectares (46.5 million acres) of forest destroyed, according to Greenpeace Russia – about two times the size of the island of Ireland.
In 2003, a series of wildfires in the taiga forests of Eastern Siberia burned over 55 million acres (22 million hectares) of land, making them some of the most devastating and largest wildfires in human history.
In 2022, wildfires in Siberia burned a significant area, with over 3.2 million hectares (approximately 7.9 million acres) affected. This included fires in both Siberian and Far East regions, with the Khabarovsk region in the Far East experiencing a large concentration of blazes.
in July 2019 in areas difficult to access in northern Krasnoyarsk Krai, the Sakha Republic and Zabaykalsky Krai, all of which are within Russia’s Siberian Province. By the end of that month the size of the fires had reached 2.6 million hectares (ha) (6.4 million acres). According to Russian News Agency TASS quoting the Krasnoyarsk Forest Fire Center, the causes of forest fires are natural due to 30-degree Celsius heat (86 degrees Fahrenheit), gusts of wind and dry thunderstorms."
NASA
2020
"Burned area and number of fires in Siberia from March through September 2020, distributed by latitudinal bands. Total burned area for Siberia in 2020 was 25.5 million ha, in almost 15,000 individual fires." International Association of Wildland Fires
25.5 hectares = 62.98 million acres burned
-----------------
6/14/24
Firefighters are battling wildfires in Brazil's Pantanal, the world's largest tropical wetland.
1.7 million acres burned.
In 2020, a huge wildfire struck the Brazilian Pantanal – the largest tropical wetland area in the world. Driven by extreme drought, high temperatures and human activities, the blaze cut through more than 44,515km² (16,916 Sq. miles or 130x130 miles) of habitat and killed an estimated 17 million vertebrates.
-----------
Canadian wildfires 2023
Based on data in the National Forestry Database, over 8000 fires occur each year, and burn an average of over 2.1 million hectares, or about 5 million acres.
2023 fires totaled 37.71 million acres as of Aug. 22. or 59,000 square miles
SEVEN Times larger area than average
The total was 47 million acres for the year.
The temperature was 101F at a town in the Yukon; and 121F at a town in Southwest Canada. That town subsequently burned to the ground.
Death Valley temperatures in Canada!
And in the beginning of June 2025 there were already 5 million acres burned, which is the average Annual number, and summer hadn't even started yet.
8/3/2025
In 2025, Canadian wildfires have burned over 13.6 million acres (5.5 million hectares).
What is *your* definition of catastrophe?
Is losing your community to accelerated sea level rise a catastrophe?
How about increasing the chance of a major problem from one in twenty years to one in ten years, like flood, river too low to transport goods, crop-destroying drought, coral bleaching, subway system flood, etc. (Consult your insurance actuary for the premiums on those.)
Is losing a municipal well to salt water intrusion a catastrophe?
Is the collapse of a local fishery a catastrophe?
Is the →increase← in power and rapid intensification of tropical cyclones a catastrophe?
If you don't think those are catastrophes, I can understand why you focus so much on the term "catastrophe" rather than on accelerated economic collapse, accelerated loss of living space, poorer crop yields, increased aridification, etc.
I'm happy you're living in some sort of climate haven where you won't lose your shelter, your food supply or your income from the land, and your power supply is not reliant on a grid vulnerable to ice storms, wildfires, or windstorms.
Scott has been asked many times, here and elsewhere, for his definition of catastrophe. I've never seen him answer the question. I think it's because he doesn't want to expose his lack of empathy for the victims of catastrophic climate change to date. So let me put it into words for him: if neither he nor anyone he cares about is a casualty, it's not a catastrophe!
It's true "catastrophe" is not scientifically defined. Nonetheless, it's appearing more and more often in peer-reviewed scientific reports and analyses of anthropogenic climate change. Scott and his fellow obstructionists here will demand a citation, so here's a Nature report on "The unprecedented Pacific Northwest heatwave of June 2021" (https://www.nature.com/articles/s41467-023-36289-3). The abstract states:
"The impacts of this event were catastrophic, including hundreds of attributable deaths across the Pacific Northwest, mass-mortalities of marine life, reduced crop and fruit yields, river flooding from rapid snow and glacier melt, and a substantial increase in wildfires—the latter contributing to landslides in the months following. These impacts provide examples we can learn from and a vivid depiction of how climate change can be so devastating."
I personally survived the personally-unprecedented event in my personal heat-pump-cooled house, hoping the power stayed on (it did, thank you). But that's merely anecdotal. And Scott can no doubt find fault with any peer-reviewed empirical report. Earnest climate realists are hereby advised: don't waste too much time crafting careful replies, you'll just be repeating yourself. He's a tar baby!
I'm not a climate change advocate (I'm against it), but there's plenty of acknowledgments of uncertainty CLEARLY DISPLAYED ON GRAPHS all over this bloody conversation. The uncertainty isn't about whether the climate is changing (it is) or sea level is rising (it is) or that polar ice is melting (it is) or that glaciers are rapidly disappearing (they are), or that heat and drought are lowering crop yields (they are), or that coral reefs worldwide—"the nurseries of the sea"—are dying at a rapid rate (they are), or that tropical cyclones are more rapidly intensifying as the world warms (physics, baby!), but how fast and by how much faster as we go along.
It's clear that you don't live on the coast of Bangladesh, or within sight of alpine glaciers, or in the parts of the world that are reaching deadly wet-bulb temperatures. You're not a fisherman in the rapidly warming Gulf of Maine, or an outdoor laborer, or the mayor of a doomed coastal town, or a wildfire fighter, or a municipal engineer that has to deal with higher and higher tides affecting a major coastal city, or a doctor that is familiar with heat stroke victims in the ER, or a resident of a town that got hit by its first Cat 5 cyclone in its centuries-old history.
So what *is* your background, that you are unaware of how bad even the best-case-scenario impacts are?
The three major factors that cause measurable coral declines along the GBR are
- storm damage (very erratic over time)
- freshwater intrusion (local major flood runoff events)
- ocean heating (variable but climbing)
The most critical issue is the increasing ocean heat. Individual bleaching events are related to local marine heat waves. As on land, regional sea temperatures are not monotonically increasing, but increasing generally (except for the North Atlantic cold blob, which models predicted would be anomalous, but even that will eventually warm up). The GBR may have the added protection that adjacent sectors can "re-seed" local damage to hard corals, but that doesn't solve the increasing heat problem.
GLOBALLY, coral bleaching events are becoming more frequent, and at some point individual coral reefs do not come back. (Death is a tipping point.) Local attempts—as in S. Florida—to "rescue" and breed more heat-resistant corals is yet another expensive attempt to mitigate the effects of ocean warming and protect our ocean food supply.
"An admission that there is uncertainty there from some of the climate change advocates would be helpful."
I'm not a "climate change advocate" (is anybody?), I'm an opponent of it. But I have no problem admitting there is uncertainty there. It's been quantified and passed peer review. Is that helpful?
I didn't see any quantification.
You see those squiggly lines on the temperature graphs up to the current time? That's the observed data. You see the smoother lines in the future from the models? That's a [weighted] average. Do you see the shaded areas around the forecast temps, THAT'S THE QUANTIFIED RANGE OF FORECAST TEMPERATURE. (Amazingly enough, sea level graphs work much the same way!)
In case you aren't familiar with these concepts in reading graphs, I suggest
https://www.wikihow.com/Read-Graphs
It's not hard to find. Try AR6 (https://www.ipcc.ch/report/ar6/wg1/chapter/chapter-4/). Or how about this: "Uncertainty Quantification of Climate Change Projections" (https://www.mss-int.sg/docs/default-source/v3_reports/v3_science_report/v3_science_report_chapter_11.pdf).
The precedent having been set, I too will resort to ALL CAPS for emphasis, shouty as it may be. Citations are for the lurkers, as it's clear Scott won't read them:
Scott: "That sounds scary! Where are the catastrophes that would go along with such a scary situation?"
Presumably, you said it twice to strengthen your point. Rest assured, Scott. Previously, you declared (https://www.theclimatebrink.com/p/climate-skeptics-have-new-favorite/comment/103237035):
Scott: "'There is no way, no how that you are going to convince me that we are living in "terrifying" times.'"
WE GET IT, SCOTT! Your own subjective judgement notwithstanding, growing numbers of others - survivors, scientists, journalists - are applying "catastrophic" to "scary situations" like the 2021 PNW heat dome, more category 5+ hurricanes at landfall, the surprise flash floods in Texas this summer, and now the global-warming-enhanced atmospheric river flooding Washington. ATTRIBUTABLE DEATHS TO DATE IN THE MILLIONS, ECONOMIC LOSSES IN THE $TRILLIONS, SCOTT! Lurkers: want peer-reviewed numbers? https://www.nature.com/articles/s41467-023-36289-3, https://www.nature.com/articles/s41467-023-41888-1, https://www.nature.com/articles/s41558-025-02399-7.
Scott: "Can't find them? Correct. They aren't there."
INCORRECT! They ARE there! You'll never find them, having ruled them out a priori. The rest of us can see them clearly, and imagine the MORTAL TERROR of the victims! SCARY ENOUGH FOR MOST OF US! WTF IS WRONG WITH YOU? NOW I'M JUST SHOUTING!
Whew! Somebody else take the mallet. Gotta pace myself. TCB needs a better class of obstructionist! RPJr is smart enough, at least.