Arguments
Climate Risk
Posted on 22 October 2024 by Ken Rice
This is a re-post from And Then There's Physics
I realise that I haven’t written anything for a while and am unlikely to become particularly prolific again anytime soon. However, there’s something I’ve been thinking about and thought that I would write a post. It relates to something Alex Trembath has written in an article about Climate Risk. Alex is the Deputy Director of the Breakthrough Institute or, as some call it, the Bad Take Institute.
Alex’s article is highlighting how people often get statistical relationships wrong, and he’s probably right. Properly interpreting statistics is difficult and it’s certainly not something I’d claim to never get wrong. The basic point he is making is that a small shift in a distribution can have a large effect on the extremes. For example, if we consider one side of a Guassian distribution, then events more extreme than 1σ, 2σ and 3σ happen 16%, 2%, and 0.1% of the time, respectively. If we then shift the distribution by 1σ, the same events will now happen 50%, 16%, and 2% of the time. Essentially, what was a 3σ event has now become about 20 times more likely.
The example Alex uses is people misunderstanding the wild swings in Nate Silver’s US election predictions. These don’t mean Silver’s model is horribly wrong. They’re happening because small shifts in the probability distribution can have a large effect on the expected outcome.
However, when it comes to extreme climate events, Alex seems to reverse the argument. For a particular event, climate change is assessed to have made that event 30 times more likely. However, the analysis also indicates that the same event would have been only a little bit less intense in a pre-industrial climate, which is what Alex seems to think is important. His point is that “[w]ith climate change, they instead tend to emphasize the statistical swings, and ignore the modesty of the shifts in the actual climate.”
I realise that how we interpret this information is somewhat subjective, so am not suggesting that Alex is wrong to highlight this. However, in my view there are some other factors to consider.
Firstly, even if climate change has essentially made this event only slightly more intense, an event that we would have regarded as extreme in a pre-industrial climate is now happening more often. Secondly, the shift of the distribution could now mean that an event that was virtually impossible in a pre-industrial climate is now possible. The 40oC experienced in the UK in 2022 may be an example of such an event. Finally, we haven’t stopped emitting GHGs into the atmosphere. So, even if climate change is only making extreme events slightly more intense now, this may not continue to be the case if we don’t get emissions to zero relatively soon (for some definition of “soon”).
There were a couple of things I found interesting about this. One was simply thinking about the statistical relationship, which I have thought about a bit before, but not in any great detail. The other is how Alex has authoritatively criticised the way in which some groups use statistics, while largely doing the same kind of thing himself; selecting the relationship that fits his own biases. That a small shift in the climate can have a large impact on the extremes seems like an important thing to highlight and focussing on the small shift would seem to be underplaying the potential impact. Of course, ideally, we should be willing to acknowledge all of the statistical inferences, rather than just focussing on those we think best suits the message we’re trying to present.
FYI, there is a fairly active discussion of this post on its original location at AndThenTheresPhysics. The link is in the green box at the top of this post, but here it is again for convenience.
https://andthentheresphysics.wordpress.com/2024/10/16/climate-risk/
Being a Greenie all my life in Australia Ive bern watching this machine funded climate change take over the whole Green movement. Ive watched thousands of forests removed for external companies for woid chip and complete devastation of climate by removal of carbon balanced cooling environments. As I now start to see a massive alkiance with tge metal industry and using net zero bs agenda to deep sea mine the largest carbon storage in our deep seas for matals for the so called S.M.A.R.T technoligical movement that is part of the W.E.F agenda its very alatming to see how this doesnt look as corrupt as the whole petrolium industry. Under most forests in rich dence metals in the soils.. I just cant help but research back to around 2008 to 2009 when the IPCC shifted focus to humans effect on global warming so only collecting data on this rather than the vast reasons on global carbon increse. Drilling in the earth can release carbon and thats exactly what this new political global agenda is about. The IPCC was done for hiking temperatures and changing glacier melting times by over 100x the year amount. With all the removal of trees around the planet for toxic solar panels is a direct attack on sustainability. Recently hearing Bill Gates saying investing in trees is not science. Yet we have 50 countries playing with geo engineering as we debate means any data from here on is not natural or at least influenced. Finding these documents have become much longer a search based on the massive influx of paid science and topics of conversation. If anyone looks up Shares in Geo Engineering it will prove how much private companies are playing god at the moment. My father was a top scientist at the Bureau of Meteorology in Melbourne. In 2013-2015 most accurate data analyists and records were defunded and CSIRO and NASA gagged them all. Its a very big hot debate and appreciate researching way back if you commonly use government controlled internet search engines. I am driving up as passenger in a car.. So I apologise in advance for my 1st draft off top of head response. Im also dyslexic but I love this site and especially love the comments. I actually cannot go back to fix via phone.
Off topic word salad interspersed by demonstrably false assertions...
Jess Scarlett, I appreciate your concerns, but the amount of CO2 released by drilling holes is totally insignificant. Even volcanic eruptions have not released enough CO2 to explain the recent warming trend. Scientists have spent thousands of hours researching these issues and every possible cause of warming and every possible source source of CO2 before ruling them out. You can find this material with a simple google search and by scanning through the information in the "climate myths" box on the left hand side of this page.
If you are suspicious of the temperature record in Australia then I suggest please look at the global surface temperature record over land. Look at the global temperature in the oceans. Look at the ballon temperature record. look at the upper atmosphere temperature record. They all show roughly the same warming trend. Urban and rural areas show the same warming trend. One set of data might be in error, but it seems very unlikely to me several would be.
Also sometimes the raw data has problems, so needs adjustments. For example data from early last century from ships were found to be in error, and the raw data was adjusted DOWN so actually reduced the warming record. This is hardly a sign of people wanting to exagerate the warming trend. If you are still sceptical about temperature data, look at the UAH satellite temperature record compiled by Roy Spencer a scientist and a climate change sceptic, but even his temperature record shows robust warming.
If you still dont believe the global temperature records, and that the world is warming, you are beyond being reasoned with.
Your comments do suggest you may have been persuaded by conspiracy theories. The idea that there is an international movement by tens of thousands of meterologists and scientists to deliberately exaggerate warming is just insanity. There is no rational motivation for such a thing. No government wants expensive problems to deal with and is certainly not going to invent them when it gets plenty dumped on its plate anyway. It would be impossible to have a giant conspiracy like this and keep it quiet. Some of these guys would leak the truth. Its like the idea that NASA faked the moon landings. This doesn't stand up to even the slightest scrutiny.
Yes the renewables have their downsides and require a lot of mining. And yes the corporate sector benefit from building renewables and sometimes the business world is a dirty affair. But what is your better solution to the climate problem? Because its a huge environmental problem that is affecting not just human society, but the natural world, and you say you are a greenie, right?
Lots of your statements are false at PC points out. And evidence free. I suggest don't let any concerns you might have that we are potentially neglecting our various other environmental problems bias you against the climate issue. I don't see evidence we are neglecting other problems. Personally I think we have to deal with both the climate problem and other environmental problems together , and humanity is obviously able to deal with several problems at the same time.
Has Judith Curry flipped into A) a climate alarmist? B) incoherence? C) a Dominionist?
Admitting that global heating will continue for centuries to come.
Paul Pukite @5,
I don't see Judy Curry having flipped.
While seeing her apparently agreeing with David Walliace-Wells is remarkable, the agreement is perhaps best seen as another instance of Judy re-defining the words of others. Over the last decade, since the WUWT failed to "change the way you think about natural internal variability" (WUWT=Wyatt's Unified Wave Theory which Judy calls the Stadium Wave), Judy has taken up ambiguity as a means of manufacturing what she calls "a wicked problem" to cloud the climate debate and give room for denialists to flaunt their nonsense.
Her book 'Climate Uncertainty and Risk : Rethinking Our Response' was published last year (a 40-odd page preview HERE) and a few months back she set out the same message at the denialist GWPF's AGM.
The book runs to fifteen chapters and 340 pages. Well hidden within it, Judy sets out her same old message, this from a book review.
(Note that the 45% number is wrong. The non-CO2 forcing is no more than 35% and over tha last decade it is down to 26%.) The hidden message from Curry is that her imagined natural climate wobbles have masked the weak nature of human-caused climate change and fooled us all. So we can sit back and enjoy ourselves while we make plans for when all the oil runs out.
So Curry has flipped into a "doomer", a term I rarely ever use since I started blogging in 2004 (apart from referencing the Science of Doom blog). Yet, a doomer with a dash of optimism has EXACTLY the same objectives as a climate change activist — the doom portended by the finiteness of fossil fuels is hedged by the transition to alternative renewable sources of energy. Same goals, the only distinction is in how rapid the transition. That's all wrapped in the #NoRegrets strategy.
All we need to do is accuse Curry of having no hope in achieving an energy transition. This should not be diffucult as she has absolutely ZERO credentials in energy engineering. She's now a totally lost soul, unable to keep up.
Paul @ 5, 7:
I wouldn't say that Curry has flipped - but I have to admit that I have not being paying a lot of attention to her and I have never had the impression that she has a coherent, logical, consistent position on much related to climate science. She would have to actually hold a position in order to be able to flip away from it. She has a history of broadcasting all sorts of whack-a-doodle stuff (calling it "interesting") - but in a way that she can deny she supported it (or opposed it) when the cards line up.
So, in that tweet, what the heck is she really claiming she has been saying for over a decade now? Only the contents of David Wallace-Wells' tweet, which says little? If you interpret his tweet as saying that there are other factors besides CO2 driving the current warming trend, and stopping CO2 emissions will have little effect, then maybe that fits her history of obfuscation and attacks on climate science as we know it. But is that what David Wallace-Wells really means?
We could try to find David Wallace-Wells' article at The Conversation. Not hard. It's here. Want more detail? The article at The Conversation links to the actual paper it is based on. It is here.
I have not read the paper in detail - it is moderately long and technical - but I can get the gist of it. It certainly does not support any argument that CO2 levels are less important than presented in the IPCC reports and positions. What the paper does seem to present is an argument (from model simulations) that the expected drop in CO2 levels after reaching net zero - due to fast parts of the carbon cycle continuing to remove CO2 - will be offset by other slow feedbacks in the climate system that will cause continued warming.
The paper uses the Australian Community Climate and Earth System Simulator Earth system model (ACCESS-ESM-1.5), which appears to include a number of slow-response feedbacks related to ice, ocean circulation, etc. (The paper provides references that explain that model in more detail, but the details are not apparent from a quick read of the current paper.)
So, the gist of this new paper seems to be that slow feedbacks often not included in many models will make things worse than expected, once net zero is reached. They also indicate that the longer we wait to reach net zero, the worse things will be.
This may fit into Curry's Uncertainty Monster scenario ("See, I told you there were things the models didn't get right!), but it is an uncertainty that will bite us in the posterior regions - not Curry's favoured "everything uncertain will fall to our benefit".
I would not be surprised if Curry hasn't actually read the paper (or maybe even the Conversation article), and just saw what she wanted to see in the tweet - without actually understanding it.
Yes, That's the entire charade of Curry's Uncertainty Monster. The uncertainty can go either way, and now that (or if) she has tilted toward a gloomish view, that uncertainty is biting back. We have long realized that atmospheric CO2 concentrations have a ratcheting effect in that once they increase, it's very difficult to reverse due to the difficulty in permamently sequestering CO2. This means the uncertainty is biased toward getting worse, and especially as in"the longer we wait to reach net zero, the worse things will be.". IOW, impossible for things to immediately get better since we require all the FF infrastructure to power us through an energy transition.
Yet, has Curry been saying this for over a decade now? It's possible that she saw the line about "climate will change" and equated that to natural variability, in which case she's been touting that for a long time. So, yes, it's rationalized by her not reading the artiicle.
Paul:
The paper in question does not seem to directly assess exactly what causes their model to continue slow warming after reaching net zero, but they discuss a number of possibilities. They discuss a number of outputs - not just global mean temperature.
How certain are they? In their abstract, they state (emphasis added) "Our findings suggest substantial long-term climate changes are possible even under net-zero emission pathways."
And in the closing section of the paper, they say things like "The results presented in this study use one of our best available modelling tools to understand future climates under net-zero emissions, but improved understanding of slow climate processes and the potential for sudden-onset changes is needed.", and "The hope with this model framework is that other groups might consider running similar simulations", and "... but further work is needed to comprehensively understand climate changes beyond emission cessation."
In other words, they are accepting that this may be a feature of their model that will not be found by others, and encourage others to try similar model experiments.
Yes, it would not surprise me if Curry is reading the tweet and misinterpreting it as "climate change because [not CO2]".
Bob, It is a slow warming shown over the span of a 1000 years. Might as well classify it as a stable temperature, which is also not totally unexpected for zero further emissions — i.e. none of the excess CO2 is sequestering. There are scores of references to an adjustment time of >> millenia for CO2.