Month: July 2023

I was talking to some friends today about climate change – in the light of the latest #AMOC paper, suggesting a tipping point. I’m far from an expert on AMOC so if you’re here for that I suggest this comprehensive piece on real climate from Stefan Rahmstorf.

Or the TL;Dr version in thread form compiled by Eleanor Frajka-Williams, PI of OCEAN:ICE sister project EPOC.

Anyway, the conversation turned to what’s going on this summer.

It’s been hot, in short and even if July has been cooler and rainy in Denmark, May and June were hot and record dry..

And it’s fair to say that, as when I’m asked why, or similar questions by journalists, there is an almost overwhelming temptation to say “we told you so”. I think that’s what Antonio Guttieres is getting at here too.

However, that’s not what I was mostly musing on. Given the apocalyptic heatwaves, strange patterns of warming in the ocean and the Antarctic sea ice loss, it feels a little like end of days.

But pretty much all of these were projected pretty accurately by scientists, even if the timing was a bit off and we’re not entirely sure what is driving that extraordinary downturn in Antarctic sea ice (but do read Zack’s piece linked here, it’s very good).

In many ways, we’re fortunate in Denmark and the rest of rich northern Europe. The worst direct impacts, at least in the near and short term, we can probably adapt to, though it will be expensive. They are mostly engineering challenges with a dollop of social science mixed in. And, we should remember that even in wealthy and well-educated Europe, how heavily climate change impacts us is very much determined by our social class.

However, in the long-term (and I do mean really long-term – on the century to millennia scale), we’re facing something more existential. We’re going to lose a lot of Danish land to sea level rise. Exactly how much will largely be determined over the next 20 to 50 years as there’s a pretty clear relationship between greenhouse gases and melting ice.

But we do have time to prepare for it- and most importantly to have some grown up conversations about our priorities as a society. This is going to require a good bit more social and behavioural science. In the medium term, we will need to prepare for ever more storm surges, but adaptation to coastal flooding also falls into the engineering category.

Of course, these local to regional risks still need dealing with and that is largely why my employer has created the awesome Danish climate atlas – to give accurate but also useful climate information to those who need to plan for the future. I suspect an ever greater part of my job will be focused on producing usable projections and climate service information. This is certainly also something we will focus on in the PRECISE project. Being able to make useful sea level rise projections is about more than identifying if an ice sheet is stable* or not, it’s also about how quickly, how likely and how much it is likely to retreat. As we have also focused on at a regional level in the PROTECT project

So that’s ice sheets and sea level. The tl;dr is, we know they’re melting, we still don’t know by how much and how fast they’ll ultimately melt but we still have time to deal with it, at least in wealthy well educated societies like Denmark,.

There is a whole nother discussion to be had about the global south and less equal societies which I don’t feel confident enough to discuss here.

Where I do think we’re more vulnerable in the shorter and medium term is perhaps surprisingly, food production – and that goes for much of Europe too. It turns out that concentrating large amounts of food production in a few key places might be a big mistake. Especially where those places are vulnerable to drought, heatwaves, over extraction of water, not to mention appalling labour conditions, an over-reliance on groundwater, artificial fertilisers and pesticides.

And then there is some evidence that multiple heatwaves could occur concurrently, threatening food production in compound events across several key regions. Perhaps working out how to make the global food chain less vulnerable to disruption at key points should be more of a focus than it is?

And that’s after the latest banditry from Russia, destroying perfectly good foodstocks and the means to distribute them, has given us a clear wake-up call on the interdependence of human society.

(Anders Puck Nielsen a military commentator has an interesting take on that from a strategic point of view here: https://youtu.be/fvPcPZP-6os which is very interesting for Ukraine watchers)

If I were a wise and concerned government I think I’d be thinking about how exactly we’re going to be feeding our population over the next 5-20 years. Where will be able to produce like Spain and Italy today? Or will diets have to change? How do we persuade people to eat more healthily and ensure that food is equitably spread through society?

This is of course also a part of the job of the other working groups, 2 and 3 of the IPCC – and it’s possibly not just an accident or indeed good lobbying that the new IPCC chair, Jim Skea, is a former WG3 coordinator. Perhaps the IPCC also sees that we have now moved into a new world.

So, these are just some of the things I’m thinking about as I prepare to go back to the office after the summer break next week.

As I observed on Mastodon after the IUGG meeting, and online with this excellent heatmap article. Climate science is entering a new phase. It’s the end of the beginning and it’s time to prepare.

*On the subject of ice sheet stability, Jeremy Bassis has an excellent thread on what this does and does not mean over on Mastodon. Worth checking out