Thread by @jolwalton

At the #COP26Universities Climate Risk Summit, enjoying the first panel on risks and attribution of extremes in a changing climate. digitalevents.uk/climaterisksum…

We have known for a very long time that one manifestation of climate change will be extreme weather events. What has changed is that we now see them happening. They are "in your face."

Two charts from IPCC WGI AR6, heatwaves and heavy precipitation. I am interested, from a climate science comms perspective, that the legend says "heavy precipitation" and Freddie Otto adds another word: "floods."

Ted Shepherd: Inspired by Schumacher's words on economics, asks how we can practice climate science as if people matter? We need to develop a conceptual framework from reality, not the other way around.

Suggests we need to develop an alternative language, honoring the necessarily plural conditional state of knowledge, against the kind of language currently prevalent in media reporting around climate.

Now @ellie_9 Director of the Commonwealth Climate and Law Initiative is talking about how climate risks translate into financial, litigation, and other legal risks, including disruption to supply chains, damage to assets, & lower productivity of exhausted overheated workers.

Understanding how these events translate into financial and legal risks means addressing how they compound and cascade (more in later sessions about that!).

There have been some dizzying advances in the attribution literature. Ellie has found with her work with business and investors that they are also often surprised by the range of litigation that is possible (and happening).

Yes, there is a stream based on causation & defendant emissions. But there can also be claims around misleading disclosures, greenwashing, failures to adapt and other areas. Claims can be ex ante, before a physical risk materialises.

Maarten van Aalst of @RCClimate bringing useful insights from a humanitarian perspective, working across many local contexts. This is not just about understanding the trends in climate hazards, but also about exposure and vulnerability.

Petra Minnerop giving more great detail on causal attribution in legal contexts, and points to examples from medical law where strict causal analysis has been softened (e.g. asbestos exposure) ...

... and where special factual circumstances can be acknowledged, to counter the "drop in the ocean" argument. Under the current paradigm, the quantification of the impact (even if probabilistic, I think?) and meeting a threshold is necessary.

Ellie praising groundbreaking legal work already going on in the Global South, and pointing to the need for further capacity building, including collaboration between legal and scientific communities to identify the evidence that can be legally leveraged to drive mitigation.

At #COP26universities Climate Risk Summit. So what do we mean by a compound climate risk? Try evacuating from floods or wildfire while social distancing. And then empowering the displaced survivors to pick up their livelihoods.

What does enforcement of NDCs look like? Some courts have used the IPCC carbon budget approach, to generate clear national thresholds. E.g. judicial review, or a non-NDC-compliant national law may be unconstitutional.

All policy, all laws need to be looked at from a climate perspective, but national governments typically do not have climate and environmental expertise across departments. #COP26Universities Climate Risk Summit

Ellie offering great detail on how climate science can use language that is already meaningful to financial communities, e.g. investment time horizons, materialities, time horizons of concern, foreseeability ... but also using moral language! Values not just value.

This session is very inspiring and wonderful (and packed with technical detail, my head is buzzing). The thing that worries me is the time scales. The urgency doesn't feel appropriate. So many of the aspirations sound like they will take five years, ten years, thirty years.

"Is it possible that even 1.5 degrees C isn't stable?" "I don't think we know completely [...] The more we limit warming, the more likely that whatever we limit to will be stable."

At #COP26Universities Climate Risk Summit, learning about research into cascades of interacting risks, with @ErikMackie, @LukaKemp, Daniel Quiggin, Aled Jones, Ellen Quigley, and Ilona Otto. A really methodologically rich field.

How do you map through the impact of a climate shock to the death of specific individuals? How do you get asset owners to acknowledges the risks posed by their assets, not only the risks to those assets? Should we & can we try to quantify cascading risks, and if so how?

Daniel Quiggin: By quantifying risks, you sometimes send the message that they somehow be avoided by adaptation, which simply isn't true. We must have mitigation front-and-centre ...

... Ellen agrees, with the proviso that there may be more radical and transformative ways of quantifying risk, i.e. holistic approach accounting for all externalities, not just risk posed to assets. Luke recalls instances when "quantification" reaches infinity.

Ellen and Ilona on inequality, within countries and between countries, as a key factor in low system resilience to all kinds of risk.

Daniel adding: cascades begin with hazards translating through vulnerabilities to impacts, so the world needs to address those vulnerabilities.

Ilona also emphasises that the toolkit of taxes and subsidies won't be rapid enough, and bans and restrictions are essential. Everyone is emphasising actually just decarbonising and the need for international cooperation.

Adaptation needs to be driven by people regionally and locally. Also a lot of agreement about the urgency of addressing inequality -- "things we'd want to do anyway, regardless of risk cascades" -- although little detail about the needed degree of equity, nor the mechanisms.

Twitter thread broke. Where's a cascade effect when you need one?