Figure from https://www.ipcc.ch/report/ar6/wg1/figures/summary-for-policymakers/figure-spm-4/
This post is by Lizzie.
The Intergovernmental Panel on Climate Change (IPCC) is a United Nations group that helps assemble the best possible information on climate change and its impacts, and then tries to communicate it to the world. In 2017 they updated their former models for emissions scenarios (representative concentration pathways, RCPs) to include socioeconomic narratives and called them Shared Socioeconomic Pathways (SSPs, oy! The acronyms).
One has been ringing in my head for a while now. And I have been meaning to track it down, especially since some ‘who could have imagined this?’ conversations that I had months ago. I am finally making the time now as I wrap up teaching climate change ecology.
Here’s the description for SSP3 — Regional Rivalry – A Rocky Road:
A resurgent nationalism, concerns about competitiveness and security, and regional conflicts push countries to increasingly focus on domestic or, at most, regional issues. Policies shift over time to become increasingly oriented toward national and regional security issues. Countries focus on achieving energy and food security goals within their own regions at the expense of broader-based development. Investments in education and technological development decline. Economic development is slow, consumption is material-intensive, and inequalities persist or worsen over time. Population growth is low in industrialized and high in developing countries. A low international priority for addressing environmental concerns leads to strong environmental degradation in some regions.
Reference here and see also this.
There’s only five narratives. Missing from them is the chance to change which one we’re on; see also the Climate Action Tracker.
Correct me if I am wrong, but scenarios that appear to be missing are ones where specific countries or groups of countries focus on narrow interests. Given the current geopolitical forces, it seems worth investigating a scenario where the US, Russia, and China focus on domestic concerns while Europe sticks to their climate policies (to cite just one plausible scenario). I think these discrete scenarios may be more important than scenarios that scope out impacts in terms of general features, as if all nations will follow the same paths. I’d like to see estimates of the difference if the US participates in international agreements or goes it alone, and it isn’t clear to me whether these scenarios include such things.
Actually, SSP2 Middle of the Road (Medium challenges to mitigation and adaptation) includes “countries making relatively good progress while others fall short of expectations.”
The world follows a path in which social, economic, and technological trends do not shift markedly from historical patterns. Development and income growth proceeds unevenly, with some countries making relatively good progress while others fall short of expectations. Global and national institutions work toward but make slow progress in achieving sustainable development goals. Environmental systems experience degradation, although there are some improvements and overall the intensity of resource and energy use declines. Global population growth is moderate and levels off in the second half of the century. Income inequality persists or improves only slowly and challenges to reducing vulnerability to societal and environmental changes remain.
Sounds like models with abstract, rather than real, countries. That’s fine as a modeling exercise, but it does avoid accountability. Given how unequal various emissions are, it matters who does what and these scenarios seem to avoid identifying actors (I could be wrong, and/or it could be deliberate).
The report you linked does some of what I wanted.
I don’t think any of the SSPs currently have the scenario you suggest, but the Climate Action Tracker pools all the policies and targets across countries to give a current expected estimate — so it does much of what I think you’re suggesting in real time. They also published a report late last year trying to estimate effects of the recent US election (https://climateactiontracker.org/documents/1277/CAT_2024-11-14_GlobalUpdate_COP29.pdf).
What could be a better predictor of the future that a statistical model based on something that has never happened? :)
It’s amazing that anyone could take any of this garbage seriously. It’s more akin nostradaumus and horoscopes than science: a mixture of imagined disaster scenarios, every one of which is bound to look kind of right sooner or later if you squint at it just right and – as always – ignore what was wrong. “One conversation with someone will suddenly spark a discussion of some sort that proves extremely valuable to you in the long run. ”
What were the probabilities ten years ago that leftists – including the massive environmental community – would be burning Tesla dealerships today? did they get that right lizzie? Where are the emissions from roasting Teslas in the various scenarios?
Which scenario includes the destruction from Stupid Mayors too Busy with DEI Signaling to Deal with Wild Fires?
The most amusing thing about the whole story is that little bits of the scenario are distintigrating day in and day out. Those climate change refugees? Oh….they live on an emphemeral sand bar in a river estuary on a trailing tectonic margin that’s been sinking for 20 million years. Oh. Those pacific atols that are going to be flooded by the rising sea? Oh. They’re actually growing, adding new land, not disappearing below the waves. Oh! you mean sea level incursion and what we thoughgt was sea level rise is caused by other human behaviors like groundwater withdrawal and massive transfers of mass (building cities) that drive sinking due to sediment compaction and isostatic subsidence? Ohhhh!!!! We didn’t know that but CLIMATE CHANGE !!!!!!
Anon:
I get that there are a lot of political things that bug you. Fair enough; there are a lot of political things that bug me too! In the meantime, climate change is real, it’s happening, it’s expected to have major disruptive effects, and it makes sense that governments and other organizations plan for and do their best to mitigate those effects.
I apologize Andrew but yuou can’t be so thick as to not recognize how numerous the confounding factors are for virtually every claim about the results of climate change, the difficulty if not impossibility of measureing those many confonding factors accurately, nor be unaware that the reason there is still so much opposition to throwing society over the railing for climate change disaster prep is that most of the claims about both what is happening and what is likely to happen have weak – at best – evidence.
Not that I’m saying you weigh the evidence on this issue. I know you don’t.
Whatever the case, the boilerplate statements that Lizzie refers to are nothing but a mix-and-match recounting of the events of human history into which almost anything can be read – just like your horoscope. They aren’t news to people with a broad education but of course we don’t ask scientist to have that. That’s why they’re continually making ridiculous claims about starvation, the end of oil, Y2K – just more press releases and attention seeking from the ever attention-hungry science community.
Anon:
This post by Phil from a few years ago might help clarify your thinking regarding the questions of decision making under climate uncertainty.
Regarding your claim about “throwing society over the railing,” recall that not making a decision or doing nothing is itself a decision.
Anon
“What could be a better predictor of the future that a statistical model based on something that has never happened?”
Aside from your ranting against whatever, this may be one of the worst things you have posted. The nature of many risks today is precisely that they are low probability-high consequence events. We’ve dropped a couple of atom bombs but we haven’t had nuclear war yet. Every nuclear power plant is subject to safety guidelines based on simulations of things that have never happened. Models are necessary for such things precisely because we lack evidence. That does not mean the models are perfect, nor that the worst case scenarios will happen or that we can model their probabilities precisely. But you seem to be advocating that there is no value in modeling things that have not happened. What a foolish and dangerous stance to take.
Also, the predicted climate change is a high-probability, low-consequence (or at least, well below background expectations) event. Where I grew up was covered in mile thick glaciers 10k years ago, the sahara was a fertile grassland 5k years ago.
We *should be* planning for those types of catastrophic changes, perhaps happening very suddenly.
Actually, it is a high probability aggregate event, but not at a more granular level and not when you start thinking about potential consequences (e.g. large migrations leading to war, sudden mass extinctions, etc. – which I consider low probability events). As to consequences, these also have an aggregate and granular distinction. A general rise in sea level is probably low consequence at an aggregate level – but the distribution of the effects is quite different.
In any case, I think one purpose of modeling is to model all types of these events, regardless of whether or not they have happened (your EMP, for example). The less evidence we have, the greater the uncertainty. But to complain about modeling things that have not happened (as anonymous did) is an absurd stance to take.
Our written history is filled with these types of events. Based on past frequency, they are essentially guaranteed to happen at least every few centuries.
I wonder how these narratives sound to political scientists and political economists. For an amateur like me, even the most dire narratives (Inequality and regional rivalry) miss the truly depressing scenario which cannot be ignored—massive wars and resource conflicts, followed by deaths of millions, which ironically may end up reduce emissions for the unfortunate reason that there are fewer people to produce emissions in the first place.
I don’t think we need to catastrophize things, but at the same time it feels irresponsible to ignore possibilities containing these outcomes.
I wish people would take the threat of an EMP as seriously. Even just due to solar activity the rate of such civilization-threatening events is about once per century or so: https://science.nasa.gov/science-research/planetary-science/23jul_superstorm/
Then theres species-threatening events like the younger dryas, super volcanoes, etc that seem to happen every ten or hundred thousand years.
A few degrees of warming or meters of sea level rise gradually over a century is no threat in comparison.
And all the disaster planning/hardening for that will also help with the more minor threats. Vice versa, this is not true at all though. On the contrary, the proposed “solutions” all make a society more fragile to real threats, which is why there is so much resistance.
Its like if theres a gang of murderous thieves trying to break in and someone tells you put the shotgun away because the gunpowder residue might cause cancer.
Also, do the latest climate models still assume the earth is not just flat, but concave in the direction of the sun?
I agree with criticisms of the SSPs on methodological grounds, but they are really just some of the canaries in the coal mine. The whole IAM project, IMO, is misconceived. We simply don’t have the theoretical or empirical tools to do for economic and political behavior that we do for earth system dynamics, yet the project of forecasting scenarios for climate mitigation requires that we use *something*. And then there are the implicit non-SSP parameters, like using CES (constant elasticity of substitution) functions for the evolution of demand and supply. And equilibrium stability assumptions. (Convexity everywhere.) And representative agents and intertemporal utility maximation, no defaults in the credit system or capital gains and losses, and so on. Of course, the models have to incorporate future technological developments, so modelers just plug in hypothetical developments in carbon dioxide withdrawal. OK, they’re useful as thought experiments, but surely not as forecasts or benchmarks.
For me, the weird thing is that there is still no technically-informed critical literature on the IAMs or what should be used in place of them. The lack of meaningful real-time benchmarks is a huge problem in climate awareness and policy.