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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.

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Comments 1 to 4:

  1. 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/

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  2. 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. 

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  3. Off topic word salad interspersed by demonstrably false assertions...

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  4. 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.

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