We have nothing to fear

[This is a mirror of a post published at PLOS. Formatting may be better over there.]


I’m scared.

I must be, because I’ve been avoiding writing this post for some time, when previously I’ve been so excited to blog I’ve written until the early hours of the morning.

I’m a climate scientist in the UK. I’m quite early in my career: I’ve worked in climate science for six and a half years since finishing my PhD in physics. I’m not a lecturer or a professor, I’m a researcher with time-limited funding. And in the past year or so I’ve spent a lot of time talking about climate science on Twittermy blog and in the comments sections of a climate sceptic blog.

So far I’ve been called a moron, a grant-grubber, disingenuous, and Clintonesque (they weren’t a fan: they meant hair-splitting), and I’ve had my honesty and scientific objectivity questioned. I’ve been told I’m making a serious error, a “big, big mistake”, that my words will be misunderstood and misused, and that I have been irritating in imposing my views on others. You might think these insults and criticisms were all from climate sceptics disparaging my work, but those in the second sentence are from a professor in climate change impacts and a climate activist. While dipping my toes in the waters of online climate science discussion, I seem to have been bitten by fish with, er, many different views.

I’m very grateful to PLOS for inviting me to blog about climate science, but it exposes me to a much bigger audience. Will I be attacked by big climate sceptic bloggers? Will I be deluged by insults in the comments, or unpleasant emails, from those who want me to tell a different story about climate change? More worryingly for my career, will I be seen by other climate scientists as an uppity young (ahem, youngish) thing, disrespectful or plain wrong about other people’s research? (Most worrying: will anyone return here to read my posts?)

I’m being a little melodramatic. But in the past year I’ve thought a lot about Fear. Like many, I sometimes find myself with imposter syndrome, the fear of being found out as incompetent, which is “commonly associated with academics”. But I’ve also been heartened by recent blog posts encouraging us to face fears of creating, and of being criticised, such as this by Gia Milinovich (a bit sweary):

“You have to face your fears and insecurity and doubt. […] That’s scary. That’s terrifying. But doing it will make you feel alive.”

Fear is a common reaction to climate change itself. A couple of days ago I had a message from an old friend that asked “How long until we’re all doomed then?” It was tongue-in-cheek, but there are many that are genuinely fearful. Some parts of the media emphasise worst case scenarios and catastrophic implications, whether from a desire to sell papers or out of genuine concern about the impacts of climate change. Some others emphasise the best case scenarios, reassuring us that everything will be fine, whether from a desire to sell papers or out of genuine concern and frustration about the difficulties of tackling climate change.

Never mind fear: it can all be overwhelming, confusing, repetitive. You might want to turn the page, to change the channel. Sometimes I’m the same.

I started blogging to try and find a new way of talking about climate science. The title of my blog is taken from a quote by a statistician:

“essentially, all models are wrong, but some are useful” – George E. P. Box (b 1919)

By “model” I mean any computer software that aims to simulate the Earth’s climate, or parts of the planet (such as forests and crops, or the Antarctic ice sheet), which we use to try to understand and predict climate changes and their impacts in the past and future. These models can never be perfect; we must always keep this in mind. On the other hand, these imperfections do not mean they are useless. The important thing is to understand their strengths and limitations.

I want to focus on the process, the way we make climate predictions, which can seem mysterious to many (including me, until about a month before starting my first job). I don’t want to try and convince you that all the predictions are doom and gloom, or conversely that everything is fine. Instead I want to tackle some of the tricky scientific questions head-on. How can we even try to predict the future of our planet? How confident are we about these predictions, and why? What could we do differently?

When people hear what I do, one of the first questions they ask is often this:

“How can we predict climate change in a hundred years, when we can’t even predict the weather in two weeks?”

To answer this question we need to define the difference between climate and weather. Here’s a good analogy I heard recently, from J. Marshall Shepherd

“Weather is like your mood. Climate is like your personality.”

And another from John Kennedy:

“Practically speaking: weather’s how you choose an outfit, climate’s how you choose your wardrobe.”

Climate, then, is long-term weather. More precisely, climate is the probability of different types of weather.

Why is it so different to predict those two things? I’m going to toss a coin four times in a row. Before I start, I want you to predict what the four coin tosses are going to be: something like “heads, tails, heads, tails”. If you get it right, you win the coin*. Ready?

[ four virtual coin tosses…]

50p coin on cafe table

[ …result is tails, tails, tails, heads ]

Did you get it right? I’m a nice person, so I’m going to give you another chance. I’m going to ask: how many heads in the next four?

four more virtual coin tosses… ]




…results is two heads out of four ]

The first of these is like predicting weather, and the second like climate. Weather is a sequence of day-by-day events, like the sequence of heads and tails. (In fact, predicting a short sequence of weather is a little easier than predicting coin tosses, because the weather tomorrow is often similar to today). Climate is the probability of different types of weather, like the probability of getting heads.

If everything stays the same, then the further you go into the future, the harder it is to predict an exact sequence and the easier it is to predict a probability. As I’ll talk about in later posts, everything is not staying the same… But hopefully this shows that trying to predict climate is not an entirely crazy idea in the way that the original question suggests.

My blog posts here at PLOS will be about common questions and misunderstandings in climate science, topical climate science news, and my own research. They won’t be about policy or what actions we should take. I will maintain my old blog allmodelsarewrong.com: all posts at PLOS will also be mirrored there, and some additional posts that are particularly technical or personal might only be posted there.

At my old blog we’ve had interesting discussions between people from across the spectrum of views, and I hope to continue that here. To aid this I have a firm commenting policy:

  • be civil; do not accuse; do not describe anyone as a denier (alternatives: sceptic, dissenter, contrarian), liar, fraud, or alarmist; do not generalise or make assumptions about others;
  • interpret comments in good faith; give others the benefit of the doubt; liberally sprinkle your comments with good humour, honesty, and, if you like them, cheerful emoticons, to keep the tone friendly and respectful;
  • stay on-topic.

I’m extremely happy to support PLOS in their commitments to make science accessible to all and to strengthen the scientific process by publishing repeat studies and negative results. I’m also very grateful to everyone that has supported and encouraged me over the past year: climate scientists and sceptics, bloggers and Tweeters. Thank you all.

And thank for you reading. My next post will be about another big question in climate science:

How can we do scientific experiments on our planet?

See you next time.

* You don’t, but if you were a volunteer at one of my talks you would.


  1. Bloke down the pub

    Hi Tamsin, good to see you’re still going strong. I’ve got one question regarding your commenting policy. If I’m not allowed to use the term ‘alarmist’ is there an approved alternative that I can use for the Chicken Littles of the world?

  2. Joe's World {Progressive Evolution}


    Measuring is an area scientist left for road builders and maps.
    Hundreds of thousand of measurements were missed that would really have helped mold physics and many, many theories.
    Failure of the above then missed critical flaws in theories due to water changes directions at the 48 degree latitude from vast velocity differences. Clouds NEVER cross the equator if you follow a world satellite plot.

    Shape plays a huge role in weight distribution,
    Our scientists, through “observation” see a box on our planet with square side and the same volume an weight in it.
    Our planet being an orb see’s a box as slightly angled out. This then effects weight distribution. Especially when you have many factors shaking that box.
    It can easily be measured by measuring the circumference of our planet surface, Every mm of height has a different measurement due to our planet shape as an orb. This can apply to water depths as well.
    Changing the shape of a glass can change the distribution of weight from being tipsy to being totally stable. This is then where the shape of hurricanes and tornadoes are shaped.

    Water does NOT give hurricane energy! Water gives the hurricane more evaporation density, but it is the height of the atmospheric winds that add to the speed of rotation.

    [ Sorry this comment got lost – was swamped by spam here — Tamsin ]

  3. Swiss Bob

    Prof Edwards,

    Please don’t worry about the insults, it’s the nature of on-line publishing where comments are allowed. Ignore them, they’re not worth worrying about. As for your work, all I can recommend is that you do the best you can and be honest about the results. As for your ‘colleagues’, you should know academia is a bitch fight 🙂

    Happy New Year.

  4. Barry Woods

    Again Good Luck at your ‘home’ blog

    As someone who has been part of the #labels debate – ‘labeling’ of people into groups, is generally not good. But sadly unavoidable, is we are to discuss anything..

    as for ‘alarmist’ – ‘climate concerned’, ‘very concerned’ or ‘extremely concerned’

    personally might come under a ‘lukewarm group’ (ref science’) or ‘not bothered’

    and ‘extremely sceptical’ with respect to policy.

    Best of Luck (who the America exremely climate concerned don’t give you a hard time.

  5. Charrette

    I admire your bravery in standing up on your own, you will grow from this as respect is earned. The open discussion of current science is always to be welcomed, even if it is not personally comfortable. Keep up the good work, there are many more people interested and observing than comment, they are the ones for whom reasoned arguement will be fruitful and it will be listened to, if you can back it up. I watch with interest.

  6. nzrobin

    Hi Tamsin,
    Sorry I’m a bit late getting to your post. I congratulate you on your honesty in your work as a scientist. I am an ageing power systems engineer with a significant interest in your topic. I have read quite a lot though. Your attitude and inquisitiveness are assets to be treasured. There will of course be those who will be threatened by this honesty though. This of course is no fault of yours. It is simply that their foundations are not all that they are cracked up to be, which will be a challenge to them. Sometimes egos can get in the way of true science. We are all human. Sometimes we have to admit we are wrong. Please do keep blogging.
    Kind regards,

  7. KnockJohn

    Hi Tamsin, I haven’t been here since your very early days but after today’s period off air, I found myself here and reading a very interesting post. Insults from blogs are, ufortunately, par for the course. I have taken part in a number of blogs on both sides of the stance on climate change and have, from time to time, been flamed for comments that I have made. – In fact, I believe that you and Richard began following me on Twitter following a Jo Abbess piece (which, if you remember was a little brusque). I once had an apology from Ray over at RC via email after one of these flames – although he left the original flaming on RC.

    Like you, I work in research but always blog under the name of KnckJohn as my views are not representative of the organization for which I work. I appreciate the efforts of those who endeavour to bring greater communication from all sides in the debate, and feel that you, Richard and Judith Curry deserve the highest admiration for continuing to do this.

    Keep up the good work.


  8. hunter

    Best wishes to your efforts at civility. And good luck resisting the pressure of peers to toe the line. Your experience, from a certain perspective, underscores the social aspect of the AGW movement: As the activist/scientist demonstrated in his/her insults and efforts at intimidation, it is not about the science or facts of the case. It is about the social power that AGW gives its true believers. It also, sadly, demonstrates a certain pettiness and childishness that is prevalent in all too much of academia, but that is a different topic.

  9. Mario McMillan

    Hey Tamsin

    Great to see you blogging again. Ignore the insults (Clintonesque would be the worst in my book) and keep your focus on the science. It changes. Adapting to that takes intelligence and courage. You have already shown both.

  10. Hank Roberts

    > Will I be attacked by big climate sceptic bloggers?

    Relax. There aren’t any.

    Odds are there are fewer of the little ones than you might think on first impression.

    There’s a great Turing Test going on, online:

    Watch for patterns — same IP address for different names, different (globally) IP addresses for the same name, email that doesn’t validate as real, botlike speed detecting and replying to new posts, piling on. One after another, online groups are eventually shocked, shocked, to find out they have had bots and socks filling up their comment threads and review collections. Someone could do a PhD thesis on the timing and patterns with which specific text strings, claims, and citations appear and get propagated.

    [Sorry this comment got lost – was swamped by spam here, ironically — Tamsin]

  11. Richard Wakefield

    Insults mean those throwing the insults can’t refute your science. It’s a common tactic of those who’s myths are being challenged. I view insults as a complement because I know my position is what the science says. Keep up with the real science. It’s rare nowadays.

  12. David in Cal

    Very nice post. I appreciate your integrity.

    I disagree with you about the significance of the coin experiment. If you already know that a coin is fair, then you can predict the long-term ratio of heads to tails. However, you have high confidence in the long-term ratio because of experience flipping virtually identical coins and because the physics is so clear. That’s not the situation with climate models. It’s not like God came down and told the scientist that his model would be correct in the long run.

    Let’s modify your coin experiment to one closer to climate models. You have a coin that may not be fair. You think it’s a fair coin, but your analysis is far from certain. Your first 8 tosses are all heads. How confident are you that the coin is fair? Bayesian statistics can be ysed to give an answer. However, common sense alone tells us that if our original prediction had high uncertainty, then flipping 8 heads in a row should significantly reduce our confidence that it’s a fair coin.

    [Sorry this comment got lost – was swamped by spam here — Tamsin]

  13. David L. Hagen

    Compliments Tamsin on blogging.
    Re:”I’m scared.”
    Good place to start.

    To advance science, we need to “love the truth”.
    Per your link to Feynman on the scientific method, we increasingly strive to conform our models to reality.
    Correcting models is key to science, and to wisdom.
    That follows from the ancient understanding of Truth.
    May I encourage exploring why some simpler models appear to track subsequent global temperatures better than current global climate models. In your search for truth, may I suggest studying Nicola Scafetta, The Global Warming Prediction Project, Roy Spencer, and Demetris Koutsoyiannis
    Batting averages improve with practice.
    Best wishes on your explorations.
    PS suggest fixing the URL to PLOS.