#2 Sink or swim

Linking extreme events to climate change and reading Angry Weather

Hi,

Welcome to my new subscribers and to the second edition of my newsletter! I am really glad you are here. If you just signed up and didn’t see the introduction in #1, there is more about me and the aims of the newsletter here. I am publishing this one a few days late in solidarity with the strikes in UK academia last week.

This week: how do we link a storm or hurricane to climate change?

In the past few years when asked by friends and family if a particular storm or heatwave was related to climate change I gave a vague answer about how it was hard to attribute a specific event to climate change as it made everything a bit worse but was hard to separate from other weather patterns.  My response has become increasingly out of date as the media has picked up and run stories on how the USA/Canadian Pacific Northwest Heatwave, Australian bushfires, and catastrophic German/Belgian floods have been made more likely by climate change, with this effect being quantified through new scientific techniques.

These are important developments with implications for areas of climate policy and action like loss and damage from climate impacts, and climate litigation i.e. suing the bad guys, as well as adaptation.

I am focusing this week’s newsletter on understanding the attribution science of climate change: how do we know if a weather event like a drought, flood, or storm is more likely due to climate change or just part of a regular weather pattern? And why does this matter?

One of the big topics from the Glasgow climate conference was how/if rich countries should pay other countries for loss and damage. This means the loss of land, property, and ways of life as climate impacts make areas uninhabitable and livelihoods too precarious to continue. There is a good explainer from ICCCAD in Bangladesh, an Institute that has led policy and action in this area, for those who want to know more.

The decisions on this were a big disappointment to many countries and activists but this topic will only continue to gain in importance and prominence in the run up to the next meeting in Egypt next year and beyond. Attribution science offers ways to prove if an event was made more likely by climate change and also to estimate the additional costs from the climate impacts. Both are key pieces of information for advancing loss and damage in the international arena.

Legal action on climate is also becoming an important area to push forward policy and action. Activists, farmers, civil society groups, young people and cities are trying to increase ambition on climate change through taking their governments or major fossil fuel companies to court. Attribution science could be an important piece of evidence to demonstrate that the negative impacts felt by communities are actually linked to or made more likely by climate change.

It is likely therefore that attribution science will become increasingly important. Whilst it is (somewhat) clear how it might support loss and damage claims and legal cases, we need to do more work to understand how best having this information can push forward responding to climate change impacts i.e. adaptation.

One of the reasons individuals, communities or policymakers do not plan ahead to adapt to climate change is a lack of clear information. The predictions on the impacts of climate change are uncertain, they don’t say exactly what might happen when, they give ranges or percentages, and people discount them.

Something that might change this equation is knowing how much of an extreme event that hit a local area - say a drought, storm or hurricane - was caused by climate change. This is something attribution science could contribute to. Equally if a government could be sued for the climate impacts a community experienced if they hadn’t prepared appropriately, this might provide a major incentive to act and adapt.

To learn more, this week I read Angry Weather by Friederike Otto, the story of how attribution science developed.

Who should read it: Anyone interested in the climate science behind the headlines

TLDR: Teams of scientists are able to do rapid studies to assess how climate change made an extreme event more or less likely. This has potentially major implications for liability for climate change losses and damages and legal cases on climate change. The big question is, will having more information make any difference to how policymakers plan for adaptation?

Friederike Otto’s Angry Weather is an introduction to the new science of climate change – attribution. This work was recognised this summer as having real impact with Otto and Geert Jan van Oldenborgh - joint pioneers of this approach - being cited amongst the world’s 100 most influential people in the Times list.

Angry Weather tells us several stories: the personal story of how Otto and the wider team came together to start work on attribution of extreme events, the day-by-day account of attributing Hurricane Harvey in the USA to climate change, and the scientific story of how attribution is actually done.

The science of attribution is to compare the weather of today with the weather we would expect if there was no anthropogenic climate change. The scientists explore weather data from the real world. E.g. How often do particular conditions emerge? How intense are the extreme events? What are the averages? They then ask the same questions using a simulated model of the area without climate change. They compare the results and can say how much more likely climate change has made a specific event (or not). If extreme rainfall happens every ten years in the real data but every hundred years in the model, then climate change has made it ten times more likely to happen.

Previously when these studies were done they would emerge a year or more after the event having gone through the usual academic process of peer review. The group Otto is part of - World Weather Attribution – turned this on its head. They apply methods that have been peer reviewed but the findings on individual weather events are released to the media and the public before undergoing the usual peer review.

The question in my mind as I was reading was how can this information be used to make better adaptation decisions?

Otto argues that attribution results can give policymakers more incentives to act.  It can also hopefully build up more public pressure to respond and raise adaptation up the political agenda. Otto argues that if information about the actual change in risk is available when people are making the decisions around how to respond after an extreme event (e.g. through rebuilding, resettling or retreating), they can make more far-sighted decisions.

This is certainly a possibility, but the wealth of social science research on how having more information does not necessarily lead to better decisions makes me a little sceptical. Having this information might provoke more questions about who benefits from delay and where power lies to make these decisions. However, if attribution science changes legal liability for losses and damages making it possible to pursue damages from governments or companies who have not done enough to adapt (or mitigate), this could radically change the adaptation incentives.

Angry Weather is a readable and entertaining introduction to the world of attribution science and the scientists who have led this new sub-discipline. To take this forward into adaptation we need to think through:

• What role can attribution science play in improving adaptation decisions that are often highly political?

• Given the lack of data in some areas, what are the justice and equity implications if extreme events in more fragile regions are not able to generate the same headlines and urgency to act?

I hope you have enjoyed today’s newsletter. Please do forward it on to colleagues and friends if so, and email or tweet me any thoughts or suggestions.

Thanks for reading,

Susannah