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Extinction, empathy, endings, beginnings


Well, this tweet didn’t age well…

A year later, I have 15,000 followers, while they have nearly a quarter of a million.

I had got into an argument with someone on Extinction Rebellion’s Twitter account in its first month of existence, while they still seemed to be a rather fringe group. They had posted a gothic image of skulls with the message “CLIMATE CHANGE = HUMAN EXTINCTION”, accompanied by a message saying it was “our moral duty to fight for life”.

My response was perhaps a little confrontational:

“Know why I hate this “Climate Change = Human Extinction” death pic? Not just [because] it’s not true or [because] fear can lead to apathy. Because it’s selfish & ignores the real issues. YOU will be ok. It is people poorer than you who will not be OK. We need empathy, not self-preservation.”

Several fellow climate scientists said they agreed with me. But the person on the XR account replied:

“[Tamsin], if you do not think or admit that #ClimateChange is an existential threat [to] life we have [to] wonder what your motives are. While it is possible that ‘fear’ can lead [to] apathy it can & does lead to cooperation & rebellion 4 #ClimateJustice. Join the #ExtinctionRebellion.”

They weren’t the first group to question my motives when talking publicly about climate science, and I’m sure they won’t be the last. Temperatures can run high on this topic.

“My motives? Surely this is about expertise/disagreement. Are you also questioning the “motives” of all the other climate scientists that endorsed my tweet?”

This is the point at which the kind supporter above had defended me.

Of course now, one year later, Extinction Rebellion have had tremendous success. Their Easter protests, along with Greta Thunberg and the BBC’s “Climate Change: The Facts” headed by David Attenborough, have persuaded a greater part of the public to care, of the media to cover, politicians to pledge.

My view of Extinction Rebellion has moved on too. As I wandered across Waterloo Bridge at Easter, I found the attitude positive and the space welcoming – a car-free, plant-filled, decorated bridge in central London seemed to me a radical but appealing claim to a better quality of life. One of their banners included the very word I’d called for: EMPATHY. I overheard a woman give an excellent explanation of the mechanism and consequences of shutdown of the Gulf Stream to two police officers, who warmly told me “I’ve learned something new today”. My friend Emily Grossman moved from curious outsider to passionate insider, and used her experience and platform as a science communicator to document the protest online. My brother Stephen Edwards, a life-long environmentalist and a sustainable housing expert, and the reason I chose a career in climate change, told me he felt more hope than he had in years.


Humility – Empathy – Frugality. Extinction Rebellion protest, Waterloo Bridge, London, Easter 2019

Things do feel new, different right now.


This is the combined impact that the #ExtinctionRebellion protests, David Attenborough film and @GretaThunberg’s visit has had on the UK media over recent days

(Mentions of “climate change” in UK media over the past 3 months, according to Factiva)

@LeoHickman, April 24, 2019


It feels like the impact of Easter 2019 has lasted. Since then, and helped by the BBC’s 50:50 gender rebalancing initiative, I’m now asked once or twice a week for a national media interviews, and hear colleagues do many more. There is such demand for female climate scientists to speak that I started an email group to help share the load. (Colleagues, please let me know if you would like to join). To me, this year has felt like banging on a door for years with no answer, then it suddenly flying off its hinges into the room. So fast that we climate scientists stumble as we cross the threshold, blinking in the bright light of greater public concern. The climate is changing…

My friend Emily asked me this summer if I would help Extinction Rebellion to check the scientific accuracy of new updates they were planning for the website. I’ve helped a little when I can (still in progress), and have been humbled by their drive, hard work and enthusiasm to learn. The science What’s App group reels by with dozens of messages discussing new studies and articles every single day.

So now, as a climate scientist, I find myself advising two groups in two very different ways. In my role as an author of the Intergovernmental Panel on Climate Change (IPCC) Sixth Assessment Report (still in progress), I assess the strength of the evidence behind different parts of climate science for policymakers. Asking: “Are we really sure this could happen?” – how many studies back it up? What are the potential weaknesses of the science? But Extinction Rebellion see their role, I think, as asking: “Are we really sure this couldn’t happen?”. In other words, applying the precautionary principle. So a prediction they present might be based on a single study, an outlier, or even an informal quote from a scientist. My aim is to assess whether they have accurately represented that study or quote, and whether we have since ruled that prediction out. It’s a completely different approach to risk.

Some months ago I talked to my partner’s son James, 15, who had been on the school strikes. I said I was struggling with how to write publicly about Extinction Rebellion: as a human, wanting to celebrate the emotion and energy of this movement and its successes, and at the same time as a professional, wanting to correct their occasional mistakes in describing the complex science. I said that the timescale of ‘12 years’ to meet the Paris Agreement temperature target of 1.5 degrees of warming was often stated with too much certainty.

“Of course, it’s actually 12 plus or minus a few years”, I said, waving my hands.

“Or. Minus.”, he replied, emphatically.

I can’t argue with that.


Tomorrow the King’s College London Department of Geography begin our induction week for the new academic year. The MSc Climate Change program that I direct will have more than fifty postgraduate students joining: more than double last year’s numbers, and more than 50:50 women. I wonder if Greta, Extinction Rebellion, the greater media coverage, have influenced their decision. In reviewing applications, I saw cover letters that described their desire for change: not only from those who had studied geography before, but also medics, biologists, people with a career in a different area. Motivated to change the world – not next year, or in 12 years, or in 2050, but right now. With empathy, with co-operation, and perhaps a bit of rebellion too.

I can’t wait to meet them.



June and July were intensely busy and rewarding. I loved supervising my first round of masters students in their dissertations: five smart, motivated women who designed projects to model and analyse the impacts of climate change and policy decisions. I was part of a fascinating panel discussion on “The Future of Aid: International Development in 2020” at the Department for International Development, where audience members described the IPCC predictions as “terrifying” and further motivation to consider climate change across all DfID activities. I talked to lawyers at the conference “General Counsels Leading the Net Zero Carbon Transition”, which gave me hope that businesses estimating and disclosing the risks of climate change and the transition to a low carbon economy (Task Force on Climate-related Financial Disclosures) will be a powerful tool of change.

General Counsels Leading the Net Zero Carbon Transition. Photo: Anthony Hobley.

I was privileged to be on a BBC staff training panel discussion on ‘Reporting Net Zero’ alongside Chris Stark, Chief Executive of the Committee on Climate Change, who provide advice to the UK government on how to reach their target of ‘net zero’ greenhouse gas emissions by 2050. In other words, what it means to not only reduce our emissions of carbon dioxide, but also to suck it out of the air.

BBC Reporting Net Zero event. Photo: Nina Goswami.

I talked about my bowel cancer of last year too: at the BlueDot festival, which I adore, and to staff at Cancer Research UK, who work hard to make cancer information more accessible to patients. (More on BlueDot in a later post). Rest and relaxation during a long August holiday have rid me of almost all my post-chemotherapy fatigue. Afterwards, I took the train to Toulouse for the third of my four IPCC author meetings, a clear mind for the first time.

I am working on a new research I am incredibly excited about – yesterday I returned from two days discussing statistical plans while walking along the beach with my academic mentor and dear friend Jonty Rougier, who is the reason I work in quantifying uncertainties for climate models and therefore write this blog.

Hastings, September 2019

I have been alternating between reading Chris Packham’s “Fingers in the Sparkle Jar: A Memoir” and Caroline Criado-Perez’s “Invisible Women: Exposing Data Bias in a World Designed for Men”. Both are extraordinary, and reveal the world in new ways. Chris Packham, like Greta Thunberg, is another line on the Asperger’s spectrum. His memoir is astonishing – full of nature’s death and childhood’s yearning to possess. I wouldn’t ever romanticise Asperger’s: I have seen how terribly challenging it can be to live with. But I have also seen how this way of thinking can shed clear light on a subject: sometimes those subjects the rest of us too comfortably glide past, such as death and injustice. Caroline’s book fills you with a creeping rage at the inequalities and dangers of a world that forgets to consider women’s needs and biology. It is also about the infuriatingly bad science that results when we do not consider the biases of our own world view.


While I was still fatigued, I slept long hazy mornings to Radio 4, and once dreamt about Greta. Wanting to share a sense of rebellion, I asked her: “Who have you been rudest to?” Greta’s a fan of black and white thinking. But in her case, I don’t mind.


  1. The Extinction R leader I met was telling the audience IPCC were not telling the ‘truth’ (and governments and media) and were in the ‘pay of’… I had an argument with him defending the IPCC scientists.. the most passive aggressive conspiracy theorist, I’ve met for years.. also had no solutions, just shouty irrational demands. Not a fan of democracy either looking at their manifestos

  2. “So a prediction they present might be based on a single study, an outlier, or even an informal quote from a scientist”

    Tamsin. ER are still using the views of such as Guy Macpherson as ‘gospel’. Their public rhetoric strongly implies that the ‘outlier’ views they promulgate are the ‘real science’ and all the rest is governments and more conventional climate scientists ‘not telling the truth’. Their primary demand for the truth to be told implies that any one who doesn’t endorse their expectation of the imminent threat of human/life extinction is not telling the truth. This is classic paranoid thinking conspiracy theorising.

    I’ve spent several decades fighting climate science denialism and I can assure you that extremist alarmism, no matter how passionately believed in, turns off the general public. ER should quote the views of the Attenboroughs not the MacPhersons.

    Denialists avidly use the irrational and extreme assertions of such as ER in their lobbying of politicians, and in their media propaganda, to undermine the ‘consensus’ science. Even ‘Saint’ Greta Thunberg allows non-climate science aims into her rhetoric, which allow the denialosphere to write her of as a pawn of international socialism!

  3. In responce to Barry and being a member of Extinction Rebellion who was deeply involved in Waterloo bridge. I met and had a long chat with IPCC’s (and the Mets offices’s) Richard Betts in 2018, I came away disillusioned about the IPCC and their attitude towards the public pics capacity to deal with he severe nature of our predicament. He admitted the IPCC were holding back because they didn’t believe the public could cope with what global scientists had to say.

    Richard and I had a chat about the media and he agreed that they have been missing in action in recent decades. The scientists have known about CEE in detail for fifty odd years, and with less detail for a lot longer. The press have not been translating the detail into information the public understand easily.

    I also know we are all human and have to work together to get us through the coming decades and centuries as best we can. We are all learning a huge amount very quickly, one of the beauties of Extinction Rebellion is that we are learning to work with people and groups with whom we wouldn’t otherwise be working, normal group dynamics of storming norming and performing have been sped up like I’ve never seen previously and it’s a joy be part of.

    We’ve not got time to change our democratic system whether we want to or not, our top priority must be to deal with global heating. However we can modify our democracy with a Citizens Assembly which stands a very strong chance of enabling the radical changes we need to usher in before 2025

    (I’m very much enjoying being a lurker on the. Science WA group)

  4. XR are not a political party – it is not a ‘manifesto’. If you are referring to Roger Hallam, he is lead by science, simply; he just believes the consistent (for the last 50 years) science! -Kind of the opposite of Conspiracy-theory!… and it is -fundamentally- rational!
    Were Martin Luther King and Gandhi anti-democratic when they voiced their concerns? No, they were appealing to Democracy.
    The IPCC have a tendency to be ‘conservative’ in their estimates, and in their findings, they express how their information is not suitable to be released to the public’! There are problems for Extinction Rebellion with the IPCC; but we are not against them!

  5. First, there is no “Sixth Wave of Extinction”. Please read the science on the subject.

    The animals and the human race are NOT in danger of extinction from a 2°C temperature rise … if they did, everyone moving from Ohio to Florida would be dead by now.

    TL;DR version? “Extinction Rebellion” is a joke, and you are not doing your scientific reputation any favors by going all girly-gushy about it …

    Next, the BBC “gender rebalancing” initiative is a good thing in that it has given you a platform. However, in general, deciding who gets a platform by inspecting their genitals is a very, very, very, very bad idea. I’m shocked that you would endorse this—it perpetuates every negative stereotype about women not being able to make it without help from men.

    Next, the precautionary principle? Really? You sure you want to go down that road? Simple answer is that it doesn’t apply here, for reasons that I detail at:

    Finally, it’s looking like Greta Thunberg and your partner’s 15-year-old son are now your go-to people for some climate questions. And you expect us to believe anything you say?

    YOU should be advising them, not the other way around, and the fact that you aren’t is … well … kinda backward.

    Overall? Sorry to say it, but this is one of your very worst blog posts ever.


  6. Actually, I’ve never heard anyone in XR (try to get it right, ER is a telly programme, or our head of state) refer to McPherson’s ‘we’ll all be extinct by 2020’ or whatever future date he decides is the new date. Sure, some of us looked at McPherson’s essay of peer reviewed science which led him to his conclusions, and understood his doomy outlook, but some of us refused to put a date on that eventuality, or just factored his views in alongside all the people who feel we will find a technological way out of this, or that there’ll be a mass change of consciousness, or some other ‘solution’. What XR does is to look at the science, and using the precautionary principle, suggest that the risk of inaction, or hoping for a technofix, is not worth waiting for. We *HAVE* to cut our ties with fossil fuels. That’s the only sensible thing to do!

    And, yes, as we clean up (optimism here!) there will be a bit of ground level warming as the aerosols and soot causing ‘dimming’ disappear. But this additional warming (a problem) isn’t a reason to keep pumping pollution into the sky!

    If you look at the main XR talk, it’s made abundantly clear that there is a continuum of viewpoints, from the very conservative IPCC which uses older, peer reviewed data, through to the informal quotes from top climate scientists who are, based on the most recent data, terrified. We need to use both the mainstream IPCC predictions AND what the most recent evidence is pointing at. For instance, Global Dimming wasn’t in the IPCC reports until the last one, but has been discussed in lay circles for many years, since soon after 2001 when temperature records showed the post 9/11 spike.

  7. Demand 2 Impossible.. Extinction R want to be pure, and just demand unicorns..

    Demand 2, net zero by 2025- is no more air travel, no gas central heating (millions of UK homes and businesses) every existing car, lorry etc banned, in the UK.. and the list continues..

    Will the public ‘agree with this (and their job losses) Who pays? what tech replaces it. any compensation for banned car, gas boiler, etc, who pays..

    If you demand the impossible and offer no solutions, the adults will eventually decide, you are not contributing.

    We have a citizens assembly, this is parliament where citizens send MPs to represent them

    “the citizens assembly” envisioned, will have ‘facilitators, and “independent groups” over seeing it.. which of course is the citizens are patsies, to give credibility, whilst the ‘facilitator and groups, direct them to a preordained outcome.(Anyone who has eve been to a public consultation on a planning matter, with a council will recognise this technique)

    So a question for Extinct R ,when people oppose you, and everything you stand for, (and they will) what will you do?

  8. This is Extinction Rebellions pinned tweet:
    We are facing an unprecedented global emergency. Life on Earth is in crisis. Scientists agree we’ve entered a period of abrupt #ClimateBreakdown & are in the midst of a #MassExtinction of our own making. The Time For Denial Is Over. It is Time to #ActNow:

    Tamsin, do you agree with this (as you are helping the science group) the state that scientists agree…

    I don’t know any climate scientists that would agree with we ARE in the midst of a mass extinction and climate breakdown. This is alarmist hysteria?

  9. really, do they..

    “they express how their information is not suitable to be released to the public”

    (gosh the scientists are hidingthe ‘truth’ from the public are they, do you realise how conspirational that sounds)

    any evidence.. about that statement

    Hearsay is not evidence, and anyway bring it on.
    I can ‘handle the truth’ can you?

    the public are adults, if ‘scientists’ can handle the ‘truth’ so can the public…

  10. thanks, you made my point, and without my typos. very eloquently..

    ref: “Their public rhetoric strongly implies that the ‘outlier’ views they promulgate are the ‘real science’ and all the rest is governments and more conventional climate scientists ‘not telling the truth’. Their primary demand for the truth to be told implies that any one who doesn’t endorse their expectation of the imminent threat of human/life extinction is not telling the truth. This is classic paranoid thinking conspiracy theorising.”

  11. Look at the end of the day, we all agree that not enough change is happening. This has to do with communication style, the precautionary principle and human psychology. The article clearly shows one persons journey of realising and accepting xr communications strategy has actually worked. There’s no need for scientists to be defensive it’s just a recognition that presenting dry facts has not enabled the hairless monkeys (all of us) to get the message (including me).

    I assume the commenters above have read the .pdf linked to on this page?

  12. Hi Caspar,

    I enjoyed our long chat after my talk to Transition Exeter last year, and I remember discussing the IPCC and the fact that it has a hard job in assessing the science when the uncertainties in future projections are so large (which I do not find reassuring – I would much rather we could rule out the largest possibilities!).

    I don’t recall the exact details, but I doubt that I would have expressed it in quite the way that you describe above – as an IPCC Lead Author 3 times, I have not seen any evidence of “holding back because they don’t believe the public could cope”. It’s far more likely that I said that the IPCC tends not to give much weight to outlier results (which would by definition include the kind of worst-case scenarios that XR is concerned about) because the assessment process gives strongest weight to the conclusions that have a multiple lines of evidence in which there is high agreement.

    The IPCC author teams will assess groundbreaking new work, but if there is just a single paper saying something then it generally won’t be given so much weight – so (for example) if a new study suggested more drastic changes than previously thought, that would be treated with caution unless or until backed it was up by further work. So I certainly don’t think anything is being held back from the public by the IPCC.

    However, it’s clear that the IPCC and XR will give different emphasis to worst-case scenarios, and this is because they are doing different things. IPCC are providing an authoritative, scientifically-rigorous assessment. XR are trying to motivate action.

    I may also have said that I disagreed with the (so far) common IPCC practice of presenting multiple model projections in terms of the multi-model average plus uncertainty. I much prefer the approach taken in, say, the UKCP18 projections in which upper, lower and central projections are shown. In my view, this makes it clearer what the “worst” and “best” cases actually are – and that even if they may be “less likely”, they can / should still be taken into consideration.

    Despite your disillusionment with IPCC, I think it’s interesting to note that the IPCC 1.5C report does seem to have been one of the factors that kick-started the recent upsurge in public concern. To me, this shows that even (or especially?) an authoritative, scientifically-rigorous scientific assessment can show people that there clearly is a major issue to be addressed here.

    On the media, yes I think there was a down-turn in coverage of climate science in the 2010s. I remember that in the late 2000’s, the BBC 10 o’clock news used to have a fairly regular slot on climate and environmental issues, often with excellent, well-researched pieces by David Shukman. He covered our 2009 conference on 4 Degrees global warming, and he gave me a real grilling on whether a 4C+ scenario by the end of this century is credible or not (it still very much is). But he did cover it. But then for some reason that slot ended up being taken by arts & culture coverage for some years. I expect I was waxing lyrical to you on that point!

    I’d be really happy to have another chat with you at some point.



  13. Having read Vaclav Smil and others, it would seem to me that the growing developing world should be the primary concern as growth there would seem to be on track to overwhelm any reduction in CO2 etc in the developed world. “What about the 4 billion additional air conditioners that will be added in the next few decades or so in the developing world” is a recent quote I read..New technology to produce large quantities of CO2 free energy should be the emphasis. New tech nuclear power looks like if implemented in developing world would improve the situation most effectively. We certainly don’t want to limit the improved lives energy provides to people living in extreme poverty.

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