Jarvis' shed

At the bottom of the virtual garden I've made a dry place where I store some homeless things I currently value. Rummaging is encouraged and forgive any mess. Here is a list of things others are kindly storing for me.

On the workbench

How much warmer is it? - When they measure global temperature change they need a pre-industrial baseline to work off. The numbers you currently see being banded about use a rather flakey baseline. Piers and I propose a way to considerably firm up that foundation which has just come out here. You can see the 2024 results here. The code for the analysis can be found here.

How much warming will kill growth? - That is a rather muddy question, but I find it is one that all sorts of folk are prepared to have a stab at. Why not have a go yourself here? The nice thing about this question is that it draws together the most familiar handles we have on the economy and climate. It isn't a large leap to be able to turn your answer to this muddy question into an estimate for how much releasing a tonne of the carbon costs the global economy. Perhaps if more of us had a clearer sight of that cost we might be less inclined to throw it out there?

Perhaps we aren't consumers? - Even if you don't see yourself as consumerist, the idea that we are consumers has become water in which we swim. It's certainly how economists see us, but those same economists are now wanting us to believe there is something called human capital, and that this dwarfs the wealth tied up in stuff (produced capital). Dan and I have had a go at estimating how much investment is needed to make all the human and produced capital the economists tell us is out there, and it turns out that close to every available penny is needed. You are not about to consume the coffee in that cup, but are instead investing in your forward evolution. Here is the pre-print for comment.

On the bike rack

A simple assessment - I teach some third year undergraduates integrated assessment modelling (among other things). They don’t have any formal economics and, therefore, we approach the problem by pairing back the complexity more than I’ve seen others attempt in order to make the material accessible to math/modelling phobes. The result hopefully offends the economic/IAM orthodoxy while being illuminating for those wanting to see some of the entrails of the integrated assessment world. The current product is a spreadsheet model and associated handout. When I have time I intend to publish this more formally. Check it out here.

Is money useful? - Who knows? But Carey and I have just published a paper where we assume it is equivalent to useful work. We express that useful work as either expanding networks in space, or making those networks more efficient. Our aim is to see what happens to primary energy use if more is invested in making things efficient. Not surprisingly, if the objective of the economy is to grow, efficiency investments cause primary energy use to also grow, but if you go all in on efficiency investments, then primary energy use does indeed go down, albeit in an economy that no longer grows. The wonder of nonlinear systems!

In the apple store

It's [mostly] the [global] economy stupid! - In the UK (and no doubt many other places) a perpetual political argument goes on over who owns the responsibility for the growth we experience, or not. Here, I see what the relationship between global and UK growth rates has to say about this. Turns out the UK is rather heavily plugged into the global economy - who would have thought!

Complex to perplex - One side effect of growth is increasing complexity. If you want some evidence for that then reflect on how things have changed in a generation. The 'Is money useful?' thread above also has something to say on this. Perhaps there's a threshold when systems transition from complex to perplex, when the promise of being able to possibly understand phenomena is replaced by complete bewilderment.

Everything flows - Having done some work looking at how long things last and how much of it there is, we wrote a short piece summarising our thinking. The take home is that everything flows, but I think it is still worth a read. You can find it here.

Student feedback - Forgive the self-aggrandising, but needed to stow some of my more positive teaching feedback from last year in here.

Tucked away at the back

Climate timescales - I just had cause to review some of my writing on timescales. Although I have become more interested in the timescales baked into economic structures and how they impact on economic inertia and the climate crisis, I think the climate feedback timescales work I did was one of my best pieces of analysis, and was a little surprised to see just how un-cited it has been. Then again, it has been rather tucked away.