{"version":"1.0.0","segments":[{"startTime":5.915,"endTime":9.523,"body":"Well, thank you very much everybody, and welcome to the ninth of our Gresham lectures"},{"startTime":9.523,"endTime":10.245,"body":"on net zero."},{"startTime":10.965,"endTime":15.565,"body":"Although this lecture will be a bit of a departure from most of, well, all"},{"startTime":15.565,"endTime":15.871,"body":"of the lectures today, which have been focused on the challenge of how do we"},{"startTime":15.871,"endTime":21.085,"body":"stop global warming?"},{"startTime":21.265,"endTime":26.223,"body":"Uh, how do we stop the rise therefore in essentially one number, the global average"},{"startTime":26.223,"endTime":26.885,"body":"surface temperature."},{"startTime":27.505,"endTime":32.942,"body":"Um, but of course that one number is, as I emphasized in the last lecturer,"},{"startTime":32.942,"endTime":36.205,"body":"hard enough even to measure, nevermind feel or experience."},{"startTime":37.065,"endTime":42.228,"body":"And what really matters to people in terms of impacts of climate change is what's"},{"startTime":42.228,"endTime":43.605,"body":"happening to our weather."},{"startTime":43.865,"endTime":49.583,"body":"So in this lecture, we'll be talking about the two ways in which climate affects"},{"startTime":49.583,"endTime":49.965,"body":"weather."},{"startTime":50.665,"endTime":54.681,"body":"So there's mull over and say, what are the, why are the two ways we'll"},{"startTime":54.681,"endTime":55.485,"body":"talk about this?"},{"startTime":56.185,"endTime":61.308,"body":"Um, so building on that, we'll talk about how we set about quantifying the role"},{"startTime":61.308,"endTime":64.724,"body":"of climate change, uh, in extreme weather events in particular."},{"startTime":64.925,"endTime":67.925,"body":"'cause it tends to be the extreme weather events that do the damage."},{"startTime":68.625,"endTime":72.525,"body":"Um, and why it is that getting this right is really starting to matter."},{"startTime":74.195,"endTime":78.656,"body":"The Gresham College lecture that you're listening to right now is giving you knowledge and"},{"startTime":78.656,"endTime":78.953,"body":"insight from one of the world's leading academic experts, making it takes a lot of"},{"startTime":78.953,"endTime":83.415,"body":"time."},{"startTime":83.915,"endTime":87.083,"body":"But because we want to encourage a love of learning, we think it's well worth"},{"startTime":87.083,"endTime":87.295,"body":"it."},{"startTime":88.275,"endTime":92.185,"body":"We never make you pay for lectures, although donations are needed, or we ask in"},{"startTime":92.185,"endTime":96.095,"body":"return is this, send a link to this lecture to someone you think would benefit."},{"startTime":96.475,"endTime":100.391,"body":"And if you haven't already, click the follow or subscribe button from wherever you are"},{"startTime":100.391,"endTime":101.175,"body":"listening right now."},{"startTime":102.235,"endTime":103.815,"body":"Now, let's get back to the lecture."},{"startTime":107.795,"endTime":112.395,"body":"I mean, at the end of the day, weather, like this storm in lanch, um,"},{"startTime":112.395,"endTime":116.995,"body":"in the west of Ireland, um, is, uh, it matters much more than global temperature."},{"startTime":117.315,"endTime":121.715,"body":"I mean, this is, this is what actually affects people's lives and livelihoods."},{"startTime":122.095,"endTime":123.795,"body":"But we have always had extreme weather."},{"startTime":123.815,"endTime":129.887,"body":"And this is a photograph I took, um, just down the coast, um, from Lynch,"},{"startTime":129.887,"endTime":135.555,"body":"um, showing that same winter of storms that destroyed this pretty old wall here."},{"startTime":136.215,"endTime":139.612,"body":"So, you know, it was a one in a hundred year perhaps event as we"},{"startTime":139.612,"endTime":139.839,"body":"assessed at the time, but as you can tell, there's some infrastructure there that had"},{"startTime":139.839,"endTime":145.955,"body":"no problem with the storms been around for a bit longer than that."},{"startTime":146.335,"endTime":149.278,"body":"And that gives you a sense of the, the perspective we have to take that,"},{"startTime":149.278,"endTime":149.474,"body":"you know, you, you get a one in a hundred year storm, but it's not"},{"startTime":149.474,"endTime":153.595,"body":"a one in a thousand year storm."},{"startTime":153.655,"endTime":157.435,"body":"And, and, and that's the kind of thing we'll be talking about in this lecture."},{"startTime":158.375,"endTime":163.587,"body":"And the reason it matters, um, is less, one thing I do get teased about"},{"startTime":163.587,"endTime":166.715,"body":"is our obsession with flooding in the Thames Valley."},{"startTime":166.715,"endTime":170.385,"body":"You're gonna hear a lot about flooding in the Thames Valley, um, in this, in"},{"startTime":170.385,"endTime":170.875,"body":"this lecture."},{"startTime":171.215,"endTime":173.82,"body":"And, uh, for those of you who live in the Thames Valley, I'm sure you'll"},{"startTime":173.82,"endTime":174.515,"body":"find this very interesting."},{"startTime":174.815,"endTime":179.299,"body":"Um, but I am occasionally, um, teased by colleagues who point out that, you know,"},{"startTime":179.299,"endTime":179.598,"body":"the floods that actually matter are probably not the ones that happen in in ox"},{"startTime":179.598,"endTime":179.897,"body":"one, but you know, that's, uh, that, that, that's been a focus of, of our,"},{"startTime":179.897,"endTime":189.165,"body":"of our attention."},{"startTime":189.225,"endTime":192.81,"body":"But so, so this is, um, some, uh, very, very serious floods that happened in"},{"startTime":192.81,"endTime":194.245,"body":"Bangladesh a couple of years ago."},{"startTime":194.585,"endTime":201.287,"body":"And it's this kind of event that was being much discussed at the recent COP"},{"startTime":201.287,"endTime":201.734,"body":"28 meeting in Dubai, where countries have agreed to contribute to a fund to pay"},{"startTime":201.734,"endTime":211.565,"body":"for loss and damage due to climate change."},{"startTime":212.305,"endTime":217.309,"body":"Um, which of course raises the question of how do we tell what is loss"},{"startTime":217.309,"endTime":219.645,"body":"and damage that's due to climate change?"},{"startTime":220.185,"endTime":222.445,"body":"And that's already becoming a contentious issue."},{"startTime":222.625,"endTime":227.467,"body":"You know, how, how are you, how are you gonna decide what, what events, uh,"},{"startTime":227.467,"endTime":229.405,"body":"should get payouts from this fund?"},{"startTime":230.585,"endTime":234.691,"body":"But we're gonna talk about, you know, as I said, more parochial level, um, OX"},{"startTime":234.691,"endTime":234.965,"body":"one."},{"startTime":235.425,"endTime":241.281,"body":"Um, and this is really what prompted this event, prompted my interest, uh, in this"},{"startTime":241.281,"endTime":244.405,"body":"whole, um, topic, uh, back in, uh, 2003."},{"startTime":244.505,"endTime":248.582,"body":"So just over 21 years ago, um, I was looking out the back door of"},{"startTime":248.582,"endTime":251.845,"body":"our house at the flood water of the Thames getting steadily closer."},{"startTime":252.705,"endTime":255.765,"body":"And this was the scene, uh, at the neighbor's house."},{"startTime":255.825,"endTime":260.887,"body":"And then just, just actually Dave Frame, who I mentioned, uh, in the, in the,"},{"startTime":260.887,"endTime":263.925,"body":"um, trillionth ton lecture who I've worked with extensively."},{"startTime":264.025,"endTime":265.645,"body":"Um, that, that, that's his front door."},{"startTime":265.645,"endTime":266.765,"body":"Just, just, just there."},{"startTime":267.145,"endTime":272.055,"body":"Um, fortunately he was renting the house, but, um, you know, it's, uh, flooding is"},{"startTime":272.055,"endTime":273.365,"body":"very traumatic for people."},{"startTime":273.625,"endTime":277.368,"body":"Um, we were pretty concerned at the time because we couldn't get sandbags for love,"},{"startTime":277.368,"endTime":279.365,"body":"no money, and the water was getting closer."},{"startTime":279.505,"endTime":283.499,"body":"We were very lucky we didn't actually end up getting flooding flooded, but, um, plenty"},{"startTime":283.499,"endTime":284.565,"body":"of neighbor neighbors did."},{"startTime":285.225,"endTime":291.61,"body":"And at the time, the sort of mantra, um, of the, uh, climate science community"},{"startTime":291.61,"endTime":294.165,"body":"was, oh, well, weather's not climate."},{"startTime":294.165,"endTime":295.125,"body":"These are weather events."},{"startTime":295.945,"endTime":299.928,"body":"Uh, what, when you're talking about climate, you're talking about global averages, global average temperature,"},{"startTime":299.928,"endTime":300.725,"body":"and so on."},{"startTime":300.895,"endTime":302.645,"body":"These weather events have nothing to do with that."},{"startTime":303.625,"endTime":307.811,"body":"And, and that, you know, the thing we kept on saying is you cannot attribute"},{"startTime":307.811,"endTime":309.765,"body":"any individual weather event to climate change."},{"startTime":311.305,"endTime":315.133,"body":"And, and this frustrated me because you had a feeling that, you know, there was"},{"startTime":315.133,"endTime":317.685,"body":"something to be done here, um, which prompted this article."},{"startTime":318.305,"endTime":324.015,"body":"Um, and the reason, of course, it was sort of getting, starting to this line,"},{"startTime":324.015,"endTime":329.725,"body":"oh, you know, you, you can't associate a particular weather event in the climate change."},{"startTime":330.105,"endTime":333.424,"body":"Uh, we're starting to wear a bit thin because people were saying this is a"},{"startTime":333.424,"endTime":333.645,"body":"one in a, you know, we, we had a whole lot of floods in Autumn"},{"startTime":333.645,"endTime":336.965,"body":"2000."},{"startTime":336.965,"endTime":337.765,"body":"We'll come back to those."},{"startTime":338.065,"endTime":340.73,"body":"And at the time everybody said, oh, there's a one in a hundred year event"},{"startTime":340.73,"endTime":340.908,"body":"or so, and there was a lot of discussion about, and then three years later,"},{"startTime":340.908,"endTime":344.285,"body":"we had the same thing."},{"startTime":344.425,"endTime":345.805,"body":"And so it's, well, okay."},{"startTime":346.065,"endTime":349.698,"body":"Um, and, and that's the point where you start thinking, okay, so, so what, what"},{"startTime":349.698,"endTime":352.605,"body":"can we say about the role of climate change in these events?"},{"startTime":353.225,"endTime":356.356,"body":"And, and this is kind of what we, uh, what it, what it boiled down"},{"startTime":356.356,"endTime":356.565,"body":"to."},{"startTime":356.585,"endTime":360.869,"body":"And I was, this is a, a line, a line in this article I was"},{"startTime":360.869,"endTime":361.155,"body":"particularly proud of, um, quoting, uh, ed Lorenz, who I think in turn was quoting"},{"startTime":361.155,"endTime":365.725,"body":"Mark Twain."},{"startTime":366.025,"endTime":367.885,"body":"Uh, climate is what you expect."},{"startTime":367.885,"endTime":369.125,"body":"Weather is what you get."},{"startTime":369.905,"endTime":373.063,"body":"So, uh, we'll talk a bit about what we mean by expect and get in"},{"startTime":373.063,"endTime":373.485,"body":"a minute."},{"startTime":373.945,"endTime":377.488,"body":"Um, and then the, the flip side of that is, well, climate is what you"},{"startTime":377.488,"endTime":377.725,"body":"affect."},{"startTime":378.155,"endTime":382.07,"body":"When we put greenhouse gases in the atmosphere, we affect the climate, but it's weather"},{"startTime":382.07,"endTime":385.725,"body":"is what gets you, uh, because it's the weather that actually, um, affects us."},{"startTime":385.945,"endTime":390.022,"body":"So if we talk about sort of what we mean by expect, you know what"},{"startTime":390.022,"endTime":393.285,"body":"we mean by expectation, what, we'll come onto that in a minute."},{"startTime":393.625,"endTime":399.447,"body":"But the, the question of attribution of linking weather events to external drivers in some"},{"startTime":399.447,"endTime":402.165,"body":"way has been around for some time."},{"startTime":402.345,"endTime":404.245,"body":"And I came across this preparing to this lecture."},{"startTime":404.715,"endTime":409.165,"body":"This was in the 1915 Coursely Journal of the Royal Meteorological Society."},{"startTime":409.165,"endTime":414.285,"body":"And they were talking about another wet winter that occurred in, uh, uh, 1415."},{"startTime":414.905,"endTime":419.031,"body":"Um, and they, this is a quote from the paper, an explanation which has been"},{"startTime":419.031,"endTime":419.306,"body":"most readily accepted by the general public Gresham audiences of the time, for example, um,"},{"startTime":419.306,"endTime":427.285,"body":"and even found favor among a few meteorologists, is the heavy artillery firing in France."},{"startTime":427.905,"endTime":431.805,"body":"Um, and Flanders is the primary cause of the unusual wetness of the winter."},{"startTime":432.385,"endTime":437.645,"body":"So people have looked for explanations for, um, weather events since time immemorial."},{"startTime":437.745,"endTime":441.805,"body":"And of course, if you go further back, you can find that, um, parole led"},{"startTime":441.805,"endTime":442.075,"body":"with ii uh, basically lost the support of the population because of a famine, which"},{"startTime":442.075,"endTime":449.925,"body":"was blamed on him for being an evil king, but it was just a famine."},{"startTime":450.345,"endTime":450.765,"body":"Anyway."},{"startTime":451.545,"endTime":456.365,"body":"So let's talk a little, let's talk a little bit about, um, the, the, uh,"},{"startTime":456.365,"endTime":456.687,"body":"the, what we mean by climate is what you expect and weather is what you"},{"startTime":456.687,"endTime":465.365,"body":"get, um, uh, with the help of a, a dice, very familiar dice."},{"startTime":465.365,"endTime":469.445,"body":"And I'm gonna ask an audience member, if you don't mind, um, helping out here."},{"startTime":469.565,"endTime":472.125,"body":"'cause it's always more convincing if I'm not the one who's throwing it."},{"startTime":472.345,"endTime":476.005,"body":"So if you could, uh, roll the dice for us, uh, somewhere around here."},{"startTime":476.085,"endTime":476.805,"body":"I think they wanted it."},{"startTime":477.065,"endTime":478.245,"body":"And call out what you get."},{"startTime":478.745,"endTime":479.325,"body":"What's a four?"},{"startTime":479.565,"endTime":479.885,"body":"A four?"},{"startTime":480.815,"endTime":481.645,"body":"Let's try again."},{"startTime":482.075,"endTime":483.285,"body":"Just keep, keep rolling it a few times."},{"startTime":483.285,"endTime":483.925,"body":"You gotta roll it a few times."},{"startTime":486.045,"endTime":489.285,"body":"A three, two."},{"startTime":489.955,"endTime":491.685,"body":"This demo doesn't always work."},{"startTime":492.115,"endTime":494.125,"body":"Okay, let's let, let me try."},{"startTime":494.795,"endTime":504.845,"body":"There's actually, okay, we got a six, we got a six, we got a six"},{"startTime":505.645,"endTime":510.645,"body":"\u003claugh\u003e,"},{"startTime":508.065,"endTime":508.845,"body":"We got a six"},{"startTime":511.425,"endTime":513.284,"body":"Loaded dice \u003claugh\u003e."},{"startTime":514.385,"endTime":516.044,"body":"But it didn't work to start with."},{"startTime":516.385,"endTime":518.205,"body":"That's the thing about a loaded dice."},{"startTime":518.625,"endTime":519.924,"body":"And it's just the same with the climate."},{"startTime":520.385,"endTime":524.569,"body":"Yes, heat waves are getting more likely, but it doesn't mean you're gonna get a"},{"startTime":524.569,"endTime":525.685,"body":"heat wave every year."},{"startTime":526.635,"endTime":528.045,"body":"Cold winters are getting less likely."},{"startTime":528.075,"endTime":530.205,"body":"Doesn't mean we're not gonna occasionally get a cold winter."},{"startTime":531.145,"endTime":534.165,"body":"So actually the demo kind of works 'cause it's obvious now."},{"startTime":534.225,"endTime":537.693,"body":"It took, but it took about two sixes before you started to think, wait a"},{"startTime":537.693,"endTime":537.925,"body":"minute."},{"startTime":538.665,"endTime":542.32,"body":"And then, and by the way, I didn't switch the dice, it was the same"},{"startTime":542.32,"endTime":542.563,"body":"dice, uh, in case you're wondering 'cause it, we sort of suddenly, um, but, um,"},{"startTime":542.563,"endTime":547.925,"body":"uh, but, but, but thank you very much."},{"startTime":547.925,"endTime":548.445,"body":"You're fired."},{"startTime":548.785,"endTime":553.631,"body":"Um, \u003claugh\u003e, it is, uh, actually, there's, I'm sure there's a whole PhD to be"},{"startTime":553.631,"endTime":553.954,"body":"done on what actually happens when you roll the dice, because it is interesting how,"},{"startTime":553.954,"endTime":563.325,"body":"um, once I got the knack of it, I was getting a six every time."},{"startTime":563.385,"endTime":566.085,"body":"But, but you can easily not get a six every time."},{"startTime":566.105,"endTime":573.264,"body":"So anyway, um, the, the, uh, but the point is, so expect we expect to"},{"startTime":573.264,"endTime":576.605,"body":"get a six one in six times."},{"startTime":576.605,"endTime":580.593,"body":"That's what we mean by the climate of the dice, uh, of a, of a"},{"startTime":580.593,"endTime":581.125,"body":"true dice."},{"startTime":581.355,"endTime":581.645,"body":"Yeah."},{"startTime":582.305,"endTime":585.805,"body":"And we, uh, and what we get is whatever the number turns up."},{"startTime":586.025,"endTime":591.454,"body":"So that's the analogy to have in your mind when you're thinking about climate and"},{"startTime":591.454,"endTime":591.815,"body":"weather and climate change works like loading the dice slowly, increasing the loading on the"},{"startTime":591.815,"endTime":597.245,"body":"dice."},{"startTime":598.145,"endTime":602.54,"body":"Um, so if I had switched the DI didn't honest, um, in that, that would've"},{"startTime":602.54,"endTime":604.005,"body":"been like a climate change."},{"startTime":604.165,"endTime":607.738,"body":"I would've, I would've changed the climate of the dice by adding some loading to"},{"startTime":607.738,"endTime":609.645,"body":"make it more likely it came up six."},{"startTime":610.505,"endTime":615.455,"body":"So that's an analogy to, to bear in mind, and it helps us just thinking"},{"startTime":615.455,"endTime":615.785,"body":"about a dice helps us think about the whole, uh, challenge of understanding the link"},{"startTime":615.785,"endTime":621.725,"body":"between weather and climate."},{"startTime":622.185,"endTime":627.866,"body":"So, um, here's a plot, um, which, uh, again, you could probably do in your"},{"startTime":627.866,"endTime":628.245,"body":"head showing, telling you what the probability is in the horizontal of rolling a certain"},{"startTime":628.245,"endTime":634.685,"body":"number of sixes."},{"startTime":634.905,"endTime":638.445,"body":"And obviously on the first roll, the probability is one six, if it's a trued"},{"startTime":638.445,"endTime":640.805,"body":"dice, this is the red dots are a trued dice."},{"startTime":641.465,"endTime":648.542,"body":"Um, and then if you want to get two sixes in a row, it's, anybody"},{"startTime":648.542,"endTime":651.845,"body":"wanna shout out 36 1 in 36?"},{"startTime":651.935,"endTime":652.605,"body":"There you go."},{"startTime":652.905,"endTime":656.325,"body":"And then the, the mental arrhythmia gets a little bit trickier now with three roles."},{"startTime":656.555,"endTime":659.125,"body":"It's one in, well, okay, six cubed and so on."},{"startTime":659.355,"endTime":659.645,"body":"Okay?"},{"startTime":660.145,"endTime":661.325,"body":"So that's what it looks like."},{"startTime":661.385,"endTime":665.885,"body":"The probabilities go down very rapidly as the number of sixes go up."},{"startTime":665.905,"endTime":669.555,"body":"So as soon as I rolled three sixes, you were all going, oh yeah, it's,"},{"startTime":669.555,"endTime":670.285,"body":"it's obviously fixed."},{"startTime":670.485,"endTime":674.551,"body":"I mean, you know, because it would've been a, you know, it, well, I can"},{"startTime":674.551,"endTime":674.822,"body":"tell you it would've been to get three sixes in a row would've been, uh,"},{"startTime":674.822,"endTime":680.245,"body":"more than one in a hundred."},{"startTime":680.965,"endTime":684.045,"body":"I just, this is the same data, but I'm just plotting it."},{"startTime":684.585,"endTime":687.485,"body":"Um, because you'll see lots of graphs like this through this talk."},{"startTime":687.825,"endTime":692.04,"body":"I'm plotting it as with probability, one in 10, one in a hundred, one in"},{"startTime":692.04,"endTime":693.445,"body":"a thousand, one in 10,000."},{"startTime":693.745,"endTime":698.326,"body":"And I'll probably start talking about return times and when in, in weather and, uh,"},{"startTime":698.326,"endTime":698.631,"body":"floods and so on, when we talk about the return time of something, we're not"},{"startTime":698.631,"endTime":705.045,"body":"really talking about a time at all."},{"startTime":705.555,"endTime":709.136,"body":"It's not the amount of time you have to wait to get the next one,"},{"startTime":709.136,"endTime":711.285,"body":"it's the probability of that thing happening this year."},{"startTime":711.315,"endTime":714.524,"body":"Well, one, over the probability of that thing happening, that's what we mean by the"},{"startTime":714.524,"endTime":715.38,"body":"return time of event."},{"startTime":715.505,"endTime":721.063,"body":"So the return time of a triple six, um, with just three roles, um, is,"},{"startTime":721.063,"endTime":721.434,"body":"uh, you know, one in one 20, you know, if you did it every day,"},{"startTime":721.434,"endTime":721.805,"body":"it'd be one in one, six cubed, whatever the, the number is, uh, 200 and"},{"startTime":721.805,"endTime":734.405,"body":"something, um, uh, day, uh, days."},{"startTime":734.945,"endTime":738.285,"body":"You know, you, you, you, you'd expect to get that once, once that, that, that,"},{"startTime":738.285,"endTime":739.845,"body":"that sort of frequency and so on."},{"startTime":740.505,"endTime":745.242,"body":"Um, now of course, if we just load the dice to make, um, getting a,"},{"startTime":745.242,"endTime":745.558,"body":"a six a one in five rather than a one in six chance, so to"},{"startTime":745.558,"endTime":754.085,"body":"load the dice a little bit, this particular dice is very heavily loaded."},{"startTime":754.145,"endTime":758.045,"body":"But you know, I suppose imagine sort of fairly subtle loading on the dice, um,"},{"startTime":758.045,"endTime":758.305,"body":"that changes the chance of getting a one in a single six from one in"},{"startTime":758.305,"endTime":763.245,"body":"six to one in five."},{"startTime":763.905,"endTime":768.888,"body":"But the chances of getting a double six go from one in 36 to one"},{"startTime":768.888,"endTime":769.885,"body":"in 25, okay?"},{"startTime":770.065,"endTime":773.946,"body":"And the chance of getting a treble six, um, go up even further and so"},{"startTime":773.946,"endTime":774.205,"body":"on."},{"startTime":774.205,"endTime":779.85,"body":"So, so what the loading does, it has some impact on, uh, the, the, the,"},{"startTime":779.85,"endTime":780.226,"body":"the, the normal events if you like, but a really extreme impact on the more"},{"startTime":780.226,"endTime":790.765,"body":"extreme events, or a different impact on the extreme events than the normal events."},{"startTime":791.145,"endTime":792.565,"body":"And we have to understand that."},{"startTime":792.945,"endTime":794.685,"body":"Now this is just a loaded dice."},{"startTime":794.745,"endTime":799.918,"body":"Now it's not, it's not generic to everything, but it tells you that you've gotta"},{"startTime":799.918,"endTime":800.263,"body":"understand how this slope, the way things get less, get less probable as they get"},{"startTime":800.263,"endTime":800.608,"body":"bigger, which is a feature of many, many things, changes as a result of the"},{"startTime":800.608,"endTime":814.405,"body":"loading is something we need to do a lot of research on."},{"startTime":814.545,"endTime":820.62,"body":"And I actually have this, this is, you know, what we've, we've jumped now from"},{"startTime":820.62,"endTime":821.025,"body":"climate research you can do with, you know, fluid in pipes and, and, um, a"},{"startTime":821.025,"endTime":821.43,"body":"handful of equations to the most sophisticated questions that confront climate resurgence today, which is"},{"startTime":821.43,"endTime":835.605,"body":"understanding what is happening to extreme weather."},{"startTime":835.625,"endTime":839.75,"body":"And we, for which we have to use the most sophisticated models we have available,"},{"startTime":839.75,"endTime":841.125,"body":"which we all come onto."},{"startTime":841.185,"endTime":844.101,"body":"And I'm actually very happy to say that a couple of people who are actually"},{"startTime":844.101,"endTime":846.045,"body":"doing this work are actually here, uh, in the audience."},{"startTime":846.705,"endTime":852.198,"body":"Um, so just to re remind you what return times, uh, look like, and this"},{"startTime":852.198,"endTime":857.325,"body":"is a boring process if you like, um, uh, just a completely random process."},{"startTime":857.385,"endTime":863.031,"body":"If I was to roll a dice, um, a true dice lots of times and"},{"startTime":863.031,"endTime":867.925,"body":"add up the dots, I end up with something called a Gaussian distribution."},{"startTime":868.005,"endTime":872.325,"body":"A a normally distributed process, the sort of bell curve of probability you expect."},{"startTime":873.065,"endTime":878.075,"body":"And if I, uh, plot here number of standard deviations in the vertical of my"},{"startTime":878.075,"endTime":883.085,"body":"bell curve, what's the probability of getting one if I just generate lots of them?"},{"startTime":883.385,"endTime":887.635,"body":"And the red dots here are lots of possible, lot, lots of gen, you know,"},{"startTime":887.635,"endTime":888.485,"body":"lots of weathers."},{"startTime":888.485,"endTime":892.885,"body":"Weather is what you get lots of rolls of this process, and you can see"},{"startTime":892.885,"endTime":893.765,"body":"they go up."},{"startTime":894.195,"endTime":899.625,"body":"It's not this straight line, unlike the dice, it curves a little bit and it"},{"startTime":899.625,"endTime":903.245,"body":"it flattens out as you get towards higher and higher."},{"startTime":903.625,"endTime":907.685,"body":"Um, uh, prob uh, lower and lower probabilities, higher and higher return times."},{"startTime":908.265,"endTime":912.212,"body":"The blue is, is the sort of what you get if you have a, like"},{"startTime":912.212,"endTime":912.475,"body":"a million, if you try it millions of times so that you get sort of"},{"startTime":912.475,"endTime":919.845,"body":"very exact estimate of what the, of what the, uh, uh, return times are."},{"startTime":920.025,"endTime":924.116,"body":"And the red shows you that when you're getting to, you know, a few, a"},{"startTime":924.116,"endTime":924.389,"body":"few tries, it starts to jump around a bit because you're in the, you're in"},{"startTime":924.389,"endTime":929.845,"body":"the noise at that point, right?"},{"startTime":930.305,"endTime":934.027,"body":"Um, but let's think about a more interesting, that's, that's, this is a kind of"},{"startTime":934.027,"endTime":935.765,"body":"boring process, one which is very familiar."},{"startTime":936.115,"endTime":938.325,"body":"This, this Gaussian process."},{"startTime":938.745,"endTime":944.851,"body":"And you could use, if you knew, you know, if you knew what you're studying"},{"startTime":944.851,"endTime":945.258,"body":"was a Gaussian, you could work out, um, from its behavior down here, you could"},{"startTime":945.258,"endTime":945.665,"body":"make a very accurate prediction of what the chances would be of getting a particularly"},{"startTime":945.665,"endTime":958.285,"body":"high magnitude event."},{"startTime":958.705,"endTime":962.592,"body":"You could, you could use weight, you know, what you know about the process here"},{"startTime":962.592,"endTime":964.925,"body":"to predict the probability of what happens out there."},{"startTime":966.185,"endTime":972.047,"body":"But that's the, the hallmark of a Gaussian process is that you're rolling the dice"},{"startTime":972.047,"endTime":975.565,"body":"and each roll is independent of the previous one."},{"startTime":976.705,"endTime":982.752,"body":"But let's think about another process that is also has a lot of randomness in"},{"startTime":982.752,"endTime":984.365,"body":"it, but watch carefully."},{"startTime":985.025,"endTime":989.085,"body":"Um, this is sand pouring out of a tube, okay?"},{"startTime":989.195,"endTime":990.125,"body":"Onto a disc."},{"startTime":991.265,"endTime":995.381,"body":"And you can see how it, it evolves, it, it climbs up and then it"},{"startTime":995.381,"endTime":996.205,"body":"slides down, okay?"},{"startTime":996.745,"endTime":1000.392,"body":"And now if you, and then you get a big slide, a big, a big"},{"startTime":1000.392,"endTime":1001.365,"body":"landslide, so to speak."},{"startTime":1002.545,"endTime":1010.63,"body":"And what's different about this process is that one roll, one grain of sand rolling"},{"startTime":1010.63,"endTime":1013.325,"body":"down bumps into another one."},{"startTime":1013.625,"endTime":1018.565,"body":"And actually it's not like rolling a dice it self, it's self reinforces."},{"startTime":1019.465,"endTime":1022.885,"body":"So it's, it's what we call self-organized criticality."},{"startTime":1022.985,"endTime":1030.198,"body":"But I mean, it, it's, it's a, it's a, it's a hallmark of chaotic systems,"},{"startTime":1030.198,"endTime":1034.045,"body":"non-linear systems which feed on themselves and don't."},{"startTime":1034.405,"endTime":1036.685,"body":"Although actually, interestingly, yeah, this is where the demo goes wrong."},{"startTime":1036.685,"endTime":1040.213,"body":"And if you watch this video, because you see it wasn't quite in the middle"},{"startTime":1040.213,"endTime":1040.448,"body":"anyway, sorry, I didn't mean to get onto that bit, but it just goes to"},{"startTime":1040.448,"endTime":1046.565,"body":"show how difficult it is to simulate chaos in the laboratory anyway."},{"startTime":1046.743,"endTime":1052.583,"body":"Um, but, but, but you get the, you get the point about when you have"},{"startTime":1052.583,"endTime":1052.972,"body":"a system that that is, um, almost as it were, self-aware, it's behavior tends to"},{"startTime":1052.972,"endTime":1053.361,"body":"be much more, you tend to get much more, um, uh, large events than you"},{"startTime":1053.361,"endTime":1067.765,"body":"would expect from the statistics of the small events."},{"startTime":1068.345,"endTime":1073.822,"body":"And a, a para, since we're having these lectures in the city of London, of"},{"startTime":1073.822,"endTime":1078.205,"body":"course a paradigmatic self-aware, but rather random process is the stock market."},{"startTime":1078.705,"endTime":1082.286,"body":"And that's exactly why you don't see that kind of Gaussian behavior in the stock"},{"startTime":1082.286,"endTime":1082.525,"body":"market."},{"startTime":1082.525,"endTime":1087.308,"body":"But you actually see, you know, big, um, big swings much more frequently than you"},{"startTime":1087.308,"endTime":1087.627,"body":"would expect if you assume the stock market was just a, and various people nodding"},{"startTime":1087.627,"endTime":1094.325,"body":"wisely, I suspect that's what they do."},{"startTime":1094.745,"endTime":1098.405,"body":"Um, so, so, so, so that's, that's an example of the kind of process."},{"startTime":1098.865,"endTime":1103.117,"body":"So we need to think about chaos in thinking about understanding the link between weather"},{"startTime":1103.117,"endTime":1103.685,"body":"and climate."},{"startTime":1104.225,"endTime":1110.855,"body":"Um, this is the original chaotic attractor proposed by Ed Lorenz back in the 1960s"},{"startTime":1110.855,"endTime":1111.297,"body":"to explain the lack of predictability, the, or the challenge of predicting, um, atmospheric weather"},{"startTime":1111.297,"endTime":1111.739,"body":"and why it was that, that, uh, weather forecasts tend to, um, go wrong, uh,"},{"startTime":1111.739,"endTime":1126.325,"body":"after only a few days."},{"startTime":1126.785,"endTime":1131.411,"body":"But I'm not gonna talk in, I'm not gonna use this to talk about predictability"},{"startTime":1131.411,"endTime":1131.719,"body":"and prediction I'm gonna use, um, so that, that, that's Ed Lauren, I'm gonna use"},{"startTime":1131.719,"endTime":1132.027,"body":"Ed Lauren's model to talk about the link between weather and climate to illustrate the"},{"startTime":1132.027,"endTime":1142.205,"body":"link between weather and climate."},{"startTime":1143.065,"endTime":1148.775,"body":"So here's a view down over the Lauren butterfly and the dots are sort of"},{"startTime":1148.775,"endTime":1154.485,"body":"what, what happened in the system in a particular hour of, of a Lauren Day."},{"startTime":1154.625,"endTime":1158.362,"body":"So it, you can imagine this is, it's a, it's a, it's a model of"},{"startTime":1158.362,"endTime":1160.605,"body":"the atmosphere, but obviously it's very idealized stylized model."},{"startTime":1161.265,"endTime":1165.285,"body":"And the blue line at the bottom shows you the distribution."},{"startTime":1166.105,"endTime":1174.699,"body":"So how often you find dots in that value of the x variable of the"},{"startTime":1174.699,"endTime":1175.845,"body":"Loren tractor."},{"startTime":1176.625,"endTime":1182.1,"body":"So you've got this attract this, this is the, the, the imagine the particle is"},{"startTime":1182.1,"endTime":1183.925,"body":"moving around in space, okay?"},{"startTime":1184.145,"endTime":1189.845,"body":"And then we're just recording where it is every hour, um, and then looking down"},{"startTime":1189.845,"endTime":1190.605,"body":"at it."},{"startTime":1190.825,"endTime":1195.746,"body":"So we're looking if this is Z in the vertical X in one direction, Y"},{"startTime":1195.746,"endTime":1196.074,"body":"in another, we're looking down at the XY plane and seeing a, a, a map"},{"startTime":1196.074,"endTime":1202.965,"body":"of its behavior and building this distribution."},{"startTime":1204.545,"endTime":1208.685,"body":"And Tim Palmer suggested this again, I think around the sort of late nineties."},{"startTime":1209.025,"endTime":1212.485,"body":"Um, here's Tim Palmer admiring a, a, a chaotic pendulum."},{"startTime":1212.955,"endTime":1219.461,"body":"What happens if you blow on the Loren butterfly, so to speak, if you impose"},{"startTime":1219.461,"endTime":1219.895,"body":"an external driver that, um, that, that pushes the rents model just in particular direction,"},{"startTime":1219.895,"endTime":1229.005,"body":"which is shown by the arrow there."},{"startTime":1229.505,"endTime":1234.46,"body":"And you can see the behavior, the, the response to this external driver is to"},{"startTime":1234.46,"endTime":1239.085,"body":"make it more likely that it's gonna sit down here in the red area."},{"startTime":1239.435,"endTime":1243.282,"body":"That, so the red ones are the forced, are the ones with the driver, the"},{"startTime":1243.282,"endTime":1244.565,"body":"blue is the original one."},{"startTime":1245.025,"endTime":1249.189,"body":"So you can see I've just added the red on here, and you can see"},{"startTime":1249.189,"endTime":1251.965,"body":"that with the forcing, it tends to sit around here."},{"startTime":1251.985,"endTime":1257.605,"body":"So imagine that's wet conditions, that's dry conditions in, in, in the atmosphere."},{"startTime":1257.865,"endTime":1261.245,"body":"The atmosphere tends to sort of hang about in the dry regime a bit more."},{"startTime":1262.265,"endTime":1267.479,"body":"And you can see that, you know, even though the, the, the, the forcing actually"},{"startTime":1267.479,"endTime":1267.827,"body":"is pushing it in, in the positive direction, you actually end up with fewer high,"},{"startTime":1267.827,"endTime":1274.085,"body":"um, high ex events."},{"startTime":1274.295,"endTime":1276.125,"body":"Fewer, fewer floods if you like."},{"startTime":1277.705,"endTime":1282.645,"body":"Um, but what we, what is interesting is if we actually look at the impact"},{"startTime":1282.645,"endTime":1282.975,"body":"of the forcing, and this is what I meant by the two ways in which"},{"startTime":1282.975,"endTime":1283.304,"body":"we need to think about climate change affecting weather, one way to think about it"},{"startTime":1283.304,"endTime":1283.634,"body":"is to think about the trajectories of the weather, the evolution of the atmosphere that"},{"startTime":1283.634,"endTime":1299.445,"body":"leads to a high impact event."},{"startTime":1300.025,"endTime":1305.687,"body":"So imagine a, a hurricane coming, making landfall in the us So there's a whole"},{"startTime":1305.687,"endTime":1309.085,"body":"series of events that happen that, that hurricane's trajectory."},{"startTime":1309.745,"endTime":1315.497,"body":"And you can ask, well, what does, what's the role of the external driver like"},{"startTime":1315.497,"endTime":1318.565,"body":"climate change in the evolution of that hurricane?"},{"startTime":1318.905,"endTime":1324.02,"body":"And we can think about this in the context of the Loren system and say,"},{"startTime":1324.02,"endTime":1325.725,"body":"take away the, uh, driver."},{"startTime":1326.025,"endTime":1331.062,"body":"So, so this is, this is where we've got that Tim Palmers, um, blowing on"},{"startTime":1331.062,"endTime":1335.765,"body":"the butterfly, and now we remove it and we look at the same trajectories."},{"startTime":1336.785,"endTime":1340.965,"body":"And you'll notice they don't go as far in the X direction."},{"startTime":1341.025,"endTime":1341.645,"body":"Can you see that?"},{"startTime":1341.645,"endTime":1346.868,"body":"The green, the green lines peak, um, slightly less far to the right than the"},{"startTime":1346.868,"endTime":1347.565,"body":"red one."},{"startTime":1347.565,"endTime":1351.492,"body":"It's quite a subtle signal, but I'm afraid, and we dealing in subtle signals when"},{"startTime":1351.492,"endTime":1353.325,"body":"we're talking about climate change and weather."},{"startTime":1354.145,"endTime":1361.205,"body":"Um, so, you know, the external driver increases the magnitude of these high X events."},{"startTime":1361.875,"endTime":1366.939,"body":"Yeah, if you just look at one event and assume it's gonna happen anyway, the"},{"startTime":1366.939,"endTime":1368.965,"body":"external driver might make it bigger."},{"startTime":1369.625,"endTime":1372.485,"body":"So that's one way in which climate climate can affect well up."},{"startTime":1373.345,"endTime":1377.778,"body":"But at the same time, if I just color in high ex events just over"},{"startTime":1377.778,"endTime":1381.325,"body":"a certain threshold, you'll see there's more blue ones than red ones."},{"startTime":1382.065,"endTime":1386.605,"body":"So the external driver is actually reducing the frequency of these high ex events."},{"startTime":1387.225,"endTime":1390.965,"body":"So these are the two ways in which climate and they needn't be the same."},{"startTime":1391.385,"endTime":1396.555,"body":"That's the point that the, there's two ways in which climate affects the, um, the,"},{"startTime":1396.555,"endTime":1397.245,"body":"the weather."},{"startTime":1397.865,"endTime":1403.453,"body":"One is by affecting the actual individual behavior of individual events by making them bigger,"},{"startTime":1403.453,"endTime":1407.925,"body":"making or, or making them smaller in, in, in, in some cases."},{"startTime":1408.665,"endTime":1411.885,"body":"And, and secondly, by affecting their probability of occurrence."},{"startTime":1412.785,"endTime":1416.101,"body":"And you need to understand both of these if you're gonna understand the link between"},{"startTime":1416.101,"endTime":1416.765,"body":"climate and weather."},{"startTime":1417.545,"endTime":1422.664,"body":"One of the, um, things I'm actually quite proud of over the past, uh, uh,"},{"startTime":1422.664,"endTime":1423.005,"body":"20 years is sort of in doing this work, um, on, uh, understand the LinkedIn"},{"startTime":1423.005,"endTime":1428.125,"body":"climate."},{"startTime":1428.125,"endTime":1431.765,"body":"Well, obviously it, it's, lots of journalists are very interested in this question."},{"startTime":1432.005,"endTime":1434.838,"body":"Whenever a weather event happens, they want, you know, they want you to, you know,"},{"startTime":1434.838,"endTime":1435.405,"body":"answer the question."},{"startTime":1435.825,"endTime":1440.54,"body":"And, and back in the early two thousands, um, I I had a lot of"},{"startTime":1440.54,"endTime":1440.855,"body":"conversations with people where they got quite exasperated with me is, can't you just answer"},{"startTime":1440.855,"endTime":1445.885,"body":"the question?"},{"startTime":1446.185,"endTime":1447.525,"body":"Is it climate change or not?"},{"startTime":1448.025,"endTime":1451.118,"body":"And I would wander off saying rabbiting on about, well, it might be making it"},{"startTime":1451.118,"endTime":1451.325,"body":"bigger."},{"startTime":1451.385,"endTime":1454.653,"body":"It might be, you know, um, and, and, you know, it might be affecting the"},{"startTime":1454.653,"endTime":1455.525,"body":"probability of the event."},{"startTime":1455.545,"endTime":1460.334,"body":"And, and, and this, what, what are we, what we've seen over the past 20"},{"startTime":1460.334,"endTime":1464.485,"body":"years is now the journalists themselves are going off and explaining all this."},{"startTime":1464.705,"endTime":1469.223,"body":"And I think we've really made, you know, testament to, to the science journalists, um,"},{"startTime":1469.223,"endTime":1469.524,"body":"surviving science journalists, uh, of, of the UK that we've, we've actually made a lot"},{"startTime":1469.524,"endTime":1469.825,"body":"of progress in, in accepting that this is actually just quite complicated, that there isn't"},{"startTime":1469.825,"endTime":1479.765,"body":"a black and white answer."},{"startTime":1480.465,"endTime":1483.045,"body":"Um, but that doesn't mean, though, there's no answer."},{"startTime":1483.555,"endTime":1486.605,"body":"It's just, it's an interesting complic slightly complicated answer."},{"startTime":1488.465,"endTime":1489.645,"body":"Um, so there we go."},{"startTime":1489.645,"endTime":1494.511,"body":"The external driver in this particular example won't of course happen generally, um, reduces the"},{"startTime":1494.511,"endTime":1495.485,"body":"frequency of high."},{"startTime":1496.145,"endTime":1497.485,"body":"So, so this is so chaos."},{"startTime":1498.215,"endTime":1498.565,"body":"Chaos."},{"startTime":1498.865,"endTime":1505.221,"body":"And the, the fact that, um, events in our atmosphere are self-reinforcing makes life particularly"},{"startTime":1505.221,"endTime":1505.645,"body":"interesting."},{"startTime":1505.745,"endTime":1510.349,"body":"It means that you can't just use the statistics of boring events, normal events to"},{"startTime":1510.349,"endTime":1512.805,"body":"predict what's gonna happen, uh, at the extreme."},{"startTime":1513.465,"endTime":1518.64,"body":"And you can also have these two ways in which external drivers affect weather by"},{"startTime":1518.64,"endTime":1523.125,"body":"through the, through their impact, impact on the magnitude and impact on probability."},{"startTime":1524.225,"endTime":1529.863,"body":"So, um, we proposed this sort of way of thinking about, um, the link between"},{"startTime":1529.863,"endTime":1530.239,"body":"climate and weather in 2003 and the later that year, in fact, we had a"},{"startTime":1530.239,"endTime":1540.765,"body":"chance to, to implement these ideas, um, in a much more, um, prominent event."},{"startTime":1540.985,"endTime":1546.137,"body":"The heat wave that occurred in the summer of 2003, uh, which was actually, it"},{"startTime":1546.137,"endTime":1548.885,"body":"caught Europe very badly, um, by, by surprise."},{"startTime":1549.465,"endTime":1551.685,"body":"Um, and you can see it had very serious consequences."},{"startTime":1552.145,"endTime":1555.045,"body":"Um, notoriously in France there were a lot of deaths."},{"startTime":1555.065,"endTime":1559.748,"body":"But actually this is a figure from southern Germany where the health system was by"},{"startTime":1559.748,"endTime":1560.685,"body":"no means overwhelmed."},{"startTime":1561.065,"endTime":1564.648,"body":"But you can see the two weeks of the heat wave, you can see the"},{"startTime":1564.648,"endTime":1565.365,"body":"spike in mortality."},{"startTime":1565.415,"endTime":1568.405,"body":"These are, these are, uh, daily, daily death rates."},{"startTime":1568.905,"endTime":1571.165,"body":"Um, that was a flu epidemic earlier in the year."},{"startTime":1571.345,"endTime":1574.803,"body":"And you can see during the heat wave, um, it you, you was, it was"},{"startTime":1574.803,"endTime":1575.033,"body":"the heat wave was, was killing people at a faster rate than the flu had"},{"startTime":1575.033,"endTime":1579.645,"body":"been, uh, earlier in the year."},{"startTime":1580.345,"endTime":1584.728,"body":"And as I say, that was actually in southern Germany, which was not the most"},{"startTime":1584.728,"endTime":1585.605,"body":"extreme, uh, temperatures."},{"startTime":1586.425,"endTime":1590.073,"body":"And so we, um, went into the, into this problem and working with Peter, start"},{"startTime":1590.073,"endTime":1590.316,"body":"at the med office in Dhi Stone, who was a postdoc in Oxford at the"},{"startTime":1590.316,"endTime":1593.965,"body":"time."},{"startTime":1594.505,"endTime":1601.445,"body":"Um, interestingly funded by the welcome trust, um, on an epidemiology, um, grant."},{"startTime":1601.865,"endTime":1606.11,"body":"So we, we were using the point of the, the point of this research as"},{"startTime":1606.11,"endTime":1606.393,"body":"we started, we, we, we realized we needed to use techniques from epidemiology, the kind"},{"startTime":1606.393,"endTime":1606.676,"body":"of the kind of techniques that we've all got gotten ever so familiar with through"},{"startTime":1606.676,"endTime":1606.96,"body":"Covid, um, about how do we work out what the, what the, uh, role of"},{"startTime":1606.96,"endTime":1622.245,"body":"climate change is in, in effecting the risk of these weather events."},{"startTime":1623.145,"endTime":1626.347,"body":"And, um, this shows, uh, apologies to the crudeness of the, the, the graph, but"},{"startTime":1626.347,"endTime":1626.561,"body":"you know, that that was then, and this, this is the kind of graphics we"},{"startTime":1626.561,"endTime":1631.045,"body":"we got away with in our papers."},{"startTime":1631.585,"endTime":1637.275,"body":"Um, and, uh, so, so the red line is, uh, if you just include human"},{"startTime":1637.275,"endTime":1637.655,"body":"influence, um, uh, simulated summer temperatures, um, various simulations, um, so there's four of them"},{"startTime":1637.655,"endTime":1643.725,"body":"plotted here."},{"startTime":1643.895,"endTime":1647.605,"body":"Green is the average if you don't include, um, human influence."},{"startTime":1647.625,"endTime":1651.645,"body":"So you can see there's a bit of a, an offset, um, in the climate."},{"startTime":1652.225,"endTime":1656.256,"body":"Um, but the individual spikes, uh, sort of as big as the offset in the"},{"startTime":1656.256,"endTime":1656.525,"body":"climate."},{"startTime":1657.105,"endTime":1660.005,"body":"And the, the black line is what actually happened."},{"startTime":1660.985,"endTime":1664.893,"body":"And you know, we used this to argue that, um, human influence on climate had"},{"startTime":1664.893,"endTime":1665.154,"body":"increased the risk of this event by around a factor of at least, at least"},{"startTime":1665.154,"endTime":1669.845,"body":"a factor of two."},{"startTime":1670.225,"endTime":1672.805,"body":"Uh, and best estimate, probably more like a factor of 10."},{"startTime":1673.465,"endTime":1679.197,"body":"Um, but you can see immediately from this figure, um, there was sort of one"},{"startTime":1679.197,"endTime":1679.579,"body":"event that looked like, yes, the model could do this, but the only way we,"},{"startTime":1679.579,"endTime":1687.605,"body":"but you know, it's not that convincing."},{"startTime":1687.825,"endTime":1690.468,"body":"And oh, by the way, I should mention because Peter would love me to mention"},{"startTime":1690.468,"endTime":1690.645,"body":"it."},{"startTime":1690.645,"endTime":1691.525,"body":"He's got a great book out."},{"startTime":1691.625,"endTime":1695.184,"body":"Um, and, uh, so it looked for Hot Air by Peter Stot, the Inside Story"},{"startTime":1695.184,"endTime":1696.845,"body":"of the Battle Against Climate Change Denial."},{"startTime":1697.265,"endTime":1702.329,"body":"Um, sorry that, that's a complete digression, but, um, uh, if you're watching Peter, you"},{"startTime":1702.329,"endTime":1703.005,"body":"owe me."},{"startTime":1703.355,"endTime":1703.645,"body":"Okay."},{"startTime":1704.025,"endTime":1708.6,"body":"Um, and, uh, the model, we, the, the, the, the, the challenge with, um, Scott"},{"startTime":1708.6,"endTime":1708.905,"body":"Stone and Allen, I mean, it was a long time ago, but there were plenty"},{"startTime":1708.905,"endTime":1715.005,"body":"of things wrong with that study."},{"startTime":1715.345,"endTime":1719.926,"body":"And the most obvious was that the model we were using, we, we, we were"},{"startTime":1719.926,"endTime":1720.231,"body":"simulating summer temperatures to see how, because when you simulate the world, you can take"},{"startTime":1720.231,"endTime":1726.645,"body":"human influence out and see what happens."},{"startTime":1726.745,"endTime":1728.485,"body":"So it's sort of, you can do experiments like that."},{"startTime":1728.825,"endTime":1734.03,"body":"Um, but um, but we were simulating the world with a model that we knew"},{"startTime":1734.03,"endTime":1735.765,"body":"couldn't actually do what happened."},{"startTime":1736.385,"endTime":1740.045,"body":"It couldn't generate a two week heat wave like the one which actually occurred."},{"startTime":1740.265,"endTime":1743.565,"body":"So we were talking, what I was showing you, there was three month averages."},{"startTime":1743.805,"endTime":1746.445,"body":"'cause that was the kind of thing this model could actually cope with."},{"startTime":1747.025,"endTime":1748.125,"body":"So that was the one problem."},{"startTime":1748.465,"endTime":1751.751,"body":"We also had very small numbers of simulations, so we had to make lots of"},{"startTime":1751.751,"endTime":1753.285,"body":"assumptions about the distributions and so on."},{"startTime":1753.505,"endTime":1757.932,"body":"And again, you are then using, um, statistics from a small number to try and"},{"startTime":1757.932,"endTime":1758.227,"body":"predict what happens in an extreme event, which again, we've just tried to explain with"},{"startTime":1758.227,"endTime":1763.245,"body":"the sand pile."},{"startTime":1763.585,"endTime":1766.79,"body":"That's, that's not what you want to, that's not ideally what you want to do"},{"startTime":1766.79,"endTime":1767.645,"body":"with a non-linear system."},{"startTime":1768.385,"endTime":1773.265,"body":"So the next step, um, was a study actually led by party Paul, um, a"},{"startTime":1773.265,"endTime":1773.59,"body":"grad student in the University of Oxford, um, who suggested, um, in 2000, uh, actually"},{"startTime":1773.59,"endTime":1773.915,"body":"in 2004 when, when, uh, our paper came out, um, he's, he just started his"},{"startTime":1773.915,"endTime":1774.241,"body":"doctorate and he, we were also running at the time the climate prediction net experiment,"},{"startTime":1774.241,"endTime":1774.566,"body":"where we were getting members of the public around the world to run the simulations"},{"startTime":1774.566,"endTime":1796.365,"body":"of the climate and send us the data back to Oxford."},{"startTime":1796.825,"endTime":1799.685,"body":"And, um, it, that was all that had all got going."},{"startTime":1799.825,"endTime":1804.823,"body":"And Pardeep suggested, um, that we could, we could apply the, this network of computers"},{"startTime":1804.823,"endTime":1805.156,"body":"around the world to, to roll the weather dice lots and lots of times in"},{"startTime":1805.156,"endTime":1805.489,"body":"order to try and address, in order to try and, um, uh, uh, address this"},{"startTime":1805.489,"endTime":1818.485,"body":"question of, of the role of human influence in extreme weather."},{"startTime":1819.145,"endTime":1823.706,"body":"Um, I, I, I think it's important to acknowledge 'cause for, for, for grad students"},{"startTime":1823.706,"endTime":1824.01,"body":"to remind us, not always listen to your supervisor, because I actually advised party strongly"},{"startTime":1824.01,"endTime":1824.314,"body":"not to do this because I figured it would be very risky and difficult and"},{"startTime":1824.314,"endTime":1834.045,"body":"slow for a PhD."},{"startTime":1834.385,"endTime":1837.25,"body":"And, and so it did take him a long time to be fair, but he"},{"startTime":1837.25,"endTime":1838.205,"body":"got funding and so on."},{"startTime":1838.205,"endTime":1841.017,"body":"He, he was able to do it, and he did get the last laugh after"},{"startTime":1841.017,"endTime":1841.205,"body":"all."},{"startTime":1841.305,"endTime":1844.466,"body":"Um, so that was his paper, which came out actually in 2011, which if you"},{"startTime":1844.466,"endTime":1844.677,"body":"do the maths, it was a very long PhD, but he, it was a, it"},{"startTime":1844.677,"endTime":1849.525,"body":"was a great result at the end of it."},{"startTime":1849.525,"endTime":1854.34,"body":"And I'm gonna show you an example, not not actually Pip's original paper, but one,"},{"startTime":1854.34,"endTime":1854.661,"body":"we, we, we worked up a bit, um, more in more detail, um, applying party's"},{"startTime":1854.661,"endTime":1862.045,"body":"approach to the UK winter of 20 13 14."},{"startTime":1862.545,"endTime":1864.285,"body":"Um, this was an extraordinary winter."},{"startTime":1864.385,"endTime":1866.765,"body":"It was, it broke the, um, the, the record."},{"startTime":1866.945,"endTime":1869.645,"body":"It was a record breaking wet winter, you probably remember it."},{"startTime":1870.065,"endTime":1875.765,"body":"Um, and, uh, here's, we, we actually maintained the world's longest daily weather record in"},{"startTime":1875.765,"endTime":1878.045,"body":"Oxford at the, uh, Radcliffe Observatory."},{"startTime":1878.425,"endTime":1883.915,"body":"Um, and here's Ian Pol, uh, making history, pouring out the, uh, the, the, the,"},{"startTime":1883.915,"endTime":1884.281,"body":"the, the flask, uh, to, to, to record the, the, the, to record the, the,"},{"startTime":1884.281,"endTime":1894.165,"body":"the record breaking, um, uh, the record breaking, uh, uh, wet, um, rainfall."},{"startTime":1894.745,"endTime":1899.115,"body":"Um, so, um, and at the time, of course, uh, everybody was talking about the"},{"startTime":1899.115,"endTime":1903.485,"body":"link with climate change, and here's David Cameron, um, trying to look scientific or something."},{"startTime":1903.865,"endTime":1908.473,"body":"Um, and, uh, and, and, and he came out saying he very much suspected this"},{"startTime":1908.473,"endTime":1908.78,"body":"was something to do with, uh, uh, climate, uh, climate change, um, and, uh, with"},{"startTime":1908.78,"endTime":1914.925,"body":"no particular evidence at the time."},{"startTime":1915.145,"endTime":1918.676,"body":"Uh, but it did sort of motivate, um, the scientific community to address the problem"},{"startTime":1918.676,"endTime":1920.325,"body":"and say, okay, well, was he right?"},{"startTime":1920.345,"endTime":1922.525,"body":"You know, was there any justification of this?"},{"startTime":1923.185,"endTime":1928.767,"body":"So the, when we're talking about, um, winter weather, um, it helps to think about,"},{"startTime":1928.767,"endTime":1933.605,"body":"um, the North Atlantic as a sort of four-sided dice, if you like."},{"startTime":1934.345,"endTime":1943.205,"body":"Um, and these curves show pressure, um, in different weather regimes in the North Atlantic."},{"startTime":1943.825,"endTime":1947.405,"body":"So here's one, the sort of northerly cold blast."},{"startTime":1948.345,"endTime":1950.125,"body":"Um, that's one weather regime."},{"startTime":1950.625,"endTime":1958.583,"body":"Um, here's a wet southwesterly, another regime, um, a very chilly easterly, but gentle, but"},{"startTime":1958.583,"endTime":1959.645,"body":"cold winds."},{"startTime":1960.105,"endTime":1962.685,"body":"And finally nice warm, uh, southerly."},{"startTime":1962.745,"endTime":1964.925,"body":"So these are the sort of four sides of the dice."},{"startTime":1964.925,"endTime":1969.471,"body":"And the question we wanted to ask ourselves was, you know, obviously what had happened"},{"startTime":1969.471,"endTime":1969.774,"body":"in uh, 20 13 14 was we had a lot of this one, the dice"},{"startTime":1969.774,"endTime":1978.565,"body":"kept on coming up, um, in, on this side, um, again and again and again."},{"startTime":1978.585,"endTime":1980.405,"body":"And, and that's what built up the floods."},{"startTime":1980.825,"endTime":1985.757,"body":"Um, and so what we did was we, we used a model now which we,"},{"startTime":1985.757,"endTime":1986.086,"body":"uh, were convinced ourselves a higher resolution model, even than the one that, um, pip"},{"startTime":1986.086,"endTime":1992.005,"body":"was using, convinced ourselves."},{"startTime":1992.025,"endTime":1994.445,"body":"The model was able to simulate what happened."},{"startTime":1995.145,"endTime":2000.148,"body":"So this shows you what actually happened in reality and what happened in one of"},{"startTime":2000.148,"endTime":2004.485,"body":"the wetter members, or the wettest 1% of our large numbers of simulations."},{"startTime":2004.545,"endTime":2008.685,"body":"So it doesn't happen all the time, but it can do what happened in reality."},{"startTime":2009.345,"endTime":2014.088,"body":"Um, so we, having convinced ourselves of that, we then rolled the dice with the"},{"startTime":2014.088,"endTime":2014.405,"body":"model."},{"startTime":2014.585,"endTime":2020.06,"body":"So experiments in silico, if you like, um, simulations of in red the world that"},{"startTime":2020.06,"endTime":2020.425,"body":"might, the world as it was in 20 13, 14, with all the drivers prescribed,"},{"startTime":2020.425,"endTime":2020.79,"body":"um, as, as, as the world as they were, um, in terms of temperature, greenhouse"},{"startTime":2020.79,"endTime":2033.565,"body":"gas concentrations, and the rest of it."},{"startTime":2034.025,"endTime":2036.525,"body":"And okay, this is back to these return time plots."},{"startTime":2036.525,"endTime":2040.925,"body":"So this is one over the probability of an event of rainfall."},{"startTime":2040.995,"endTime":2044.005,"body":"That high is one in a hundred, okay?"},{"startTime":2044.395,"endTime":2044.685,"body":"Prob."},{"startTime":2044.865,"endTime":2049.965,"body":"So it's the same plot I showed you with the dice, but it's just now"},{"startTime":2049.965,"endTime":2052.685,"body":"simulations, uh, of the weather of that winter."},{"startTime":2052.784,"endTime":2056.293,"body":"And each dot corresponds to one simulation, which is why it was, uh, tremendously helpful"},{"startTime":2056.293,"endTime":2059.804,"body":"to us to have all these members of the public doing these simulations for us."},{"startTime":2060.005,"endTime":2062.284,"body":"'cause there's a lot of simulations that need to be done."},{"startTime":2062.284,"endTime":2064.045,"body":"This is only showing you a small fraction of them."},{"startTime":2064.465,"endTime":2068.59,"body":"So you can see that the red is simulations of the world as it was"},{"startTime":2068.59,"endTime":2069.965,"body":"in 20, uh, 14, 15."},{"startTime":2070.545,"endTime":2076.125,"body":"And the blue is simulations of the world as it might've been without human influence."},{"startTime":2076.625,"endTime":2081.377,"body":"Uh, if you, if you sort of reverted to 19th century greenhouse gas concentrations and"},{"startTime":2081.377,"endTime":2081.694,"body":"changed the surface temperatures of the model to be to an estimate of what the"},{"startTime":2081.694,"endTime":2082.011,"body":"world would've been like, uh, back, um, uh, 150 years ago or, or back in"},{"startTime":2082.011,"endTime":2094.685,"body":"the way it would've been if we hadn't raised greenhouse gas concentrations."},{"startTime":2095.264,"endTime":2099.165,"body":"And as you can see, there's a, a change in the risk."},{"startTime":2099.165,"endTime":2101.925,"body":"There's a shift from blue to red."},{"startTime":2102.315,"endTime":2105.045,"body":"It's not huge around a 40% increase in risk."},{"startTime":2105.585,"endTime":2110.376,"body":"So this was the bottom line of this study was that, yeah, human influence had"},{"startTime":2110.376,"endTime":2110.695,"body":"increased the risk of this, um, flooding the floods that occurred in 20 13 14"},{"startTime":2110.695,"endTime":2116.765,"body":"by a fairly modest amount."},{"startTime":2117.465,"endTime":2122.387,"body":"Um, and, uh, so, you know, maybe Cameron got it just right by stroking his"},{"startTime":2122.387,"endTime":2126.325,"body":"chin and looking sort of thoughtful because it's not a huge signal."},{"startTime":2126.935,"endTime":2130.405,"body":"There are other stronger ones, and it's not always the result you get."},{"startTime":2131.025,"endTime":2136.341,"body":"Um, this was the autumn 2000 case, which par, uh, did, and he found a"},{"startTime":2136.341,"endTime":2139.885,"body":"doubling of the risk, a hundred percent increase in risk."},{"startTime":2140.625,"endTime":2146.54,"body":"Um, but interestingly, uh, the following year, um, Allison Kay at the Center for Ecology"},{"startTime":2146.54,"endTime":2146.934,"body":"in hydrology in Wallingford, um, did a study where she considered how climate change had"},{"startTime":2146.934,"endTime":2156.005,"body":"affected the risk of an event that didn't happen."},{"startTime":2157.105,"endTime":2160.765,"body":"So she asked, well, we didn't have floods in the spring of 2001."},{"startTime":2162.025,"endTime":2165.88,"body":"Um, how did, how would climate change have affected the possibility of us having floods"},{"startTime":2165.88,"endTime":2167.165,"body":"in the spring of 2001?"},{"startTime":2167.305,"endTime":2170.085,"body":"And what she found was, interestingly, there was a decrease in risk."},{"startTime":2170.745,"endTime":2177.661,"body":"And why, because the heaviest flood events in Britain in the spring occur because of"},{"startTime":2177.661,"endTime":2179.045,"body":"rapid snow melt."},{"startTime":2179.825,"endTime":2182.485,"body":"And we don't get that anymore because of climate change."},{"startTime":2183.185,"endTime":2188.981,"body":"So risks of different events are changing, and they're all, they're, they're, they're all changing"},{"startTime":2188.981,"endTime":2192.845,"body":"because of climate change, but they're changing in different directions."},{"startTime":2193.105,"endTime":2198.186,"body":"And that's really important if you know, because you still get, you could still get"},{"startTime":2198.186,"endTime":2198.525,"body":"a spring flood, but should you prepare for more spring floods is as a result"},{"startTime":2198.525,"endTime":2204.285,"body":"of climate change."},{"startTime":2204.745,"endTime":2207.005,"body":"And the answer is, well, you've gotta go and do some work to find out."},{"startTime":2208.265,"endTime":2213.712,"body":"And we shouldn't just assume because bad weather happens that it, it it's definitely going"},{"startTime":2213.712,"endTime":2215.165,"body":"to become more frequent."},{"startTime":2215.785,"endTime":2220.11,"body":"Um, you may remember, uh, there was a big argument, um, in 2011, I think,"},{"startTime":2220.11,"endTime":2220.399,"body":"about whether, whether we needed to invest in more snowblowers for Heathrow because of climate"},{"startTime":2220.399,"endTime":2224.725,"body":"change."},{"startTime":2225.625,"endTime":2227.165,"body":"Um, we didn't."},{"startTime":2227.465,"endTime":2229.805,"body":"Um, and I think that was the correct answer."},{"startTime":2229.825,"endTime":2234.032,"body":"Of course, I may be proved wrong by subsequent events, but, but all the evidence"},{"startTime":2234.032,"endTime":2234.312,"body":"is that actually heavy snow events such as we had in 2011, I think it"},{"startTime":2234.312,"endTime":2241.605,"body":"was, are actually getting much less likely, um, because of climate change."},{"startTime":2241.825,"endTime":2247.934,"body":"So probabilities are changing, and it's really important to understand how, um, and one of"},{"startTime":2247.934,"endTime":2248.342,"body":"the key things that Freddie Otto introduced into this was relating these different ways of"},{"startTime":2248.342,"endTime":2258.525,"body":"quantifying the impact of climate change on an extreme weather event."},{"startTime":2258.915,"endTime":2264.771,"body":"There's the red lines which show you the, um, in increase in, uh, magnitude in"},{"startTime":2264.771,"endTime":2268.285,"body":"the vertical, or change in probability in the horizontal."},{"startTime":2268.625,"endTime":2274.238,"body":"And they both suggest that, um, the, if we look at, um, the, uh, if"},{"startTime":2274.238,"endTime":2274.612,"body":"we look at the, the changes we might reach the conclusion this event has been"},{"startTime":2274.612,"endTime":2282.845,"body":"made much more likely because of climate change."},{"startTime":2282.845,"endTime":2284.645,"body":"So it's mostly because of climate change."},{"startTime":2285.505,"endTime":2291.424,"body":"But if we also remember what would've happened, um, in a normal year, we very"},{"startTime":2291.424,"endTime":2295.765,"body":"often find that there's a big contribution from chance as well."},{"startTime":2296.665,"endTime":2301.327,"body":"And so you can have rather sterile arguments about whether an event is mainly due"},{"startTime":2301.327,"endTime":2301.637,"body":"to human influence and whether it's mainly due to, um, uh, whether it's mainly due"},{"startTime":2301.637,"endTime":2308.165,"body":"to, um, luck or, or bad luck."},{"startTime":2308.505,"endTime":2310.205,"body":"And the answer is always, well, it's a bit of both."},{"startTime":2310.585,"endTime":2315.418,"body":"Um, and the understanding how these different things contribute, um, is, is the essence of"},{"startTime":2315.418,"endTime":2319.285,"body":"what we do in understanding the link in climate change and weather."},{"startTime":2320.465,"endTime":2325.171,"body":"Um, which brings us to a, a very different approach, which I just want to"},{"startTime":2325.171,"endTime":2325.485,"body":"acknowledge."},{"startTime":2325.685,"endTime":2329.425,"body":"Although in the, the length of this lecture, I can't really go into this approach"},{"startTime":2329.425,"endTime":2333.165,"body":"in, in detail, um, which has pioneered by Ted Shepherd at the University of Reading."},{"startTime":2333.825,"endTime":2337.125,"body":"Um, we're all very obsessed by the attribution problem in Thames Valley."},{"startTime":2337.585,"endTime":2343.706,"body":"Um, but, um, Ted, uh, considered the, if you remember the, the picture with the,"},{"startTime":2343.706,"endTime":2344.114,"body":"the, the, the Lorenza tractor, the impact of the forcing on an individual trajectory that"},{"startTime":2344.114,"endTime":2352.685,"body":"was already going in a particular direction."},{"startTime":2352.715,"endTime":2354.565,"body":"What, what difference did climate change make?"},{"startTime":2355.265,"endTime":2359.519,"body":"And, and this is what, uh, Ted calls the storyline approach to attribution where you,"},{"startTime":2359.519,"endTime":2359.802,"body":"you take out or put in the influence of human, you know, you, you, you"},{"startTime":2359.802,"endTime":2360.086,"body":"simulate an event and then you take out or put in the, the role of"},{"startTime":2360.086,"endTime":2360.369,"body":"human influence into that simulation to see what it does to the size of the"},{"startTime":2360.369,"endTime":2372.565,"body":"event."},{"startTime":2372.785,"endTime":2377.875,"body":"And, and this is an example, uh, which he gave of Hurricane Sandy, um, a"},{"startTime":2377.875,"endTime":2382.965,"body":"with a superstorm Superstorm Sandy, uh, which, uh, clobbered New York a few years ago."},{"startTime":2383.345,"endTime":2387.41,"body":"And, and this is with observed sea surface temperatures at the time, you can see"},{"startTime":2387.41,"endTime":2388.765,"body":"the intensity of the storm."},{"startTime":2389.105,"endTime":2392.916,"body":"And this was if you modified the sea surface temperatures to make them more light,"},{"startTime":2392.916,"endTime":2395.965,"body":"sort of what they would've been back in the seventies or so."},{"startTime":2396.225,"endTime":2400.251,"body":"And, and you can show there's a, you know, the storm is, was intensified by"},{"startTime":2400.251,"endTime":2401.325,"body":"the sea surface temperature."},{"startTime":2401.325,"endTime":2404.858,"body":"So this is an example of how you can trace out the, the role of"},{"startTime":2404.858,"endTime":2405.565,"body":"a particular driver."},{"startTime":2406.105,"endTime":2410.285,"body":"Now, did this is not thinking about ties at all."},{"startTime":2410.355,"endTime":2415.436,"body":"This is saying Superstorm Sandy happened, but what we're asking is how did climate change"},{"startTime":2415.436,"endTime":2418.485,"body":"modify what actually happened when Superstorm Sandy went home?"},{"startTime":2419.065,"endTime":2423.989,"body":"Um, I wanna get onto what we're doing now, um, and, uh, 'cause I, 'cause"},{"startTime":2423.989,"endTime":2424.317,"body":"I, you know, this, this is bringing you right up to date to where, um,"},{"startTime":2424.317,"endTime":2424.645,"body":"if attribution is going and, and, uh, uh, to, because all of those studies that"},{"startTime":2424.645,"endTime":2424.974,"body":"I've talked about up until now have been using models that are essentially making a"},{"startTime":2424.974,"endTime":2442.045,"body":"lot of compromises in their representation, uh, of the weather."},{"startTime":2442.785,"endTime":2447.567,"body":"And, and they tend to be at their weakest when talking about the most extreme"},{"startTime":2447.567,"endTime":2448.205,"body":"weather events."},{"startTime":2448.625,"endTime":2453.353,"body":"But there are a class of models out there, they're in use every day that"},{"startTime":2453.353,"endTime":2455.245,"body":"actually simulate extreme weather extremely well."},{"startTime":2455.825,"endTime":2458.805,"body":"And those are the models that are actually used for weather forecasting."},{"startTime":2459.065,"endTime":2462.999,"body":"And if I showed you these two, these are a syn, one of these is"},{"startTime":2462.999,"endTime":2465.885,"body":"a synthetic satellite picture, the other one is a real one."},{"startTime":2466.305,"endTime":2469.338,"body":"And, and I asked you, you know, which is which, you know, you have to,"},{"startTime":2469.338,"endTime":2471.765,"body":"you have to take a, take a moment to think about it."},{"startTime":2471.765,"endTime":2475.485,"body":"If you, if you're into this sort of thing, you can, you can tell what"},{"startTime":2475.485,"endTime":2475.733,"body":"the, what the issues are with the model, but that's a where satellite observation, and"},{"startTime":2475.733,"endTime":2481.685,"body":"this is the European Centers 18 kilometer ensemble forecasting system."},{"startTime":2481.685,"endTime":2486.06,"body":"That's the, the model that up until a couple of months ago when they increased"},{"startTime":2486.06,"endTime":2486.352,"body":"the resolution to nine kilometers, the European Center, uh, for medium range weather forecasting in"},{"startTime":2486.352,"endTime":2493.645,"body":"Redding was using to generate its weather forecasts twice a day."},{"startTime":2494.625,"endTime":2498.934,"body":"And the crucial thing about these models is they are scrutinized relentlessly because if this"},{"startTime":2498.934,"endTime":2499.221,"body":"model fails to simulate an extreme event, well, it's not that somebody gets fired, but"},{"startTime":2499.221,"endTime":2499.509,"body":"you know, there's a, there's a, there's a, there's a SWAT team comes in straight"},{"startTime":2499.509,"endTime":2509.565,"body":"away to say, well, what went wrong?"},{"startTime":2509.565,"endTime":2512.885,"body":"Because, you know, they need, they need to get the forecast right."},{"startTime":2513.385,"endTime":2516.645,"body":"Um, and if you, if you miss events in the forecast, that's the worst."},{"startTime":2516.985,"endTime":2520.578,"body":"If you miss an event e even if the event's not particularly predictable, if you,"},{"startTime":2520.578,"endTime":2520.818,"body":"if you fail to say that it might happen, um, then that's a, that's a"},{"startTime":2520.818,"endTime":2521.057,"body":"real, um, you know, well in advance then that, that's a real failure of the"},{"startTime":2521.057,"endTime":2528.005,"body":"forecast."},{"startTime":2528.465,"endTime":2532.89,"body":"So, um, this is, uh, uh, the nice graphic produced by, by Nick Leach who's"},{"startTime":2532.89,"endTime":2533.185,"body":"here showing and whose work I'm now moving on to talking about, um, showing the"},{"startTime":2533.185,"endTime":2541.445,"body":"contrast between, you know, what you get out of, um, a weather forecast model."},{"startTime":2541.445,"endTime":2545.529,"body":"This is water vapor swirling around over the North Atlantic and what it would look"},{"startTime":2545.529,"endTime":2548.525,"body":"like in a climate type climate, a climate type model here."},{"startTime":2548.685,"endTime":2553.045,"body":"So if you're thinking about an extreme event like a storm here, you can see"},{"startTime":2553.045,"endTime":2553.335,"body":"immediately it's gonna be sort of smeared out and, and you're not gonna capture the,"},{"startTime":2553.335,"endTime":2561.765,"body":"the real, uh, statistics that of, of the, of the events that actually do damage."},{"startTime":2563.185,"endTime":2567.927,"body":"So just to, uh, as an example, um, I'm gonna, um, tell you about the,"},{"startTime":2567.927,"endTime":2571.405,"body":"the first application of this to a, a damaging weather event."},{"startTime":2572.025,"endTime":2575.232,"body":"Um, uh, Nick did start off by looking at a heat wave in February, which"},{"startTime":2575.232,"endTime":2575.446,"body":"wasn't, didn't, didn't, you know, like a heat wave in the UK in February, in"},{"startTime":2575.446,"endTime":2575.66,"body":"some parts of the world, a heat wave in February does lots of damage, but"},{"startTime":2575.66,"endTime":2575.874,"body":"it was a UK heat wave, um, um, which was interesting meteorologically, but it wasn't"},{"startTime":2575.874,"endTime":2585.925,"body":"particularly interesting to the public."},{"startTime":2586.115,"endTime":2589.365,"body":"This was an event, um, that was extremely interesting to the public."},{"startTime":2589.585,"endTime":2596.053,"body":"Um, the heat wave that occurred in the Pacific Northwest in June, uh, 2021 when,"},{"startTime":2596.053,"endTime":2596.485,"body":"and, uh, work with, uh, between Nick and Anja Weiser, um, uh, where we saw,"},{"startTime":2596.485,"endTime":2596.916,"body":"um, an excursion out of the distribution of peak summer temperatures that was just several"},{"startTime":2596.916,"endTime":2610.285,"body":"standard deviations out."},{"startTime":2610.305,"endTime":2615.135,"body":"And you see something like that, that's the time to start thinking about sand piles"},{"startTime":2615.135,"endTime":2615.457,"body":"because yes, you could have a, a a, a random process like that, which suddenly"},{"startTime":2615.457,"endTime":2615.779,"body":"does something like that, but it's, you, you'd have to be, you know, you'd have"},{"startTime":2615.779,"endTime":2626.085,"body":"to be pretty unlucky."},{"startTime":2626.235,"endTime":2629.808,"body":"It's sort of, you suddenly, you, you're trundling along and suddenly you roll a, a"},{"startTime":2629.808,"endTime":2630.285,"body":"triple sex."},{"startTime":2630.665,"endTime":2635.15,"body":"Um, and, and, uh, so, so, um, and he caused, you know, the, the event"},{"startTime":2635.15,"endTime":2636.645,"body":"caused a lot of damage."},{"startTime":2636.645,"endTime":2641.033,"body":"There was a lot of, um, uh, the tone, tone of litten in British Columbia"},{"startTime":2641.033,"endTime":2641.326,"body":"set the all time Canadian, uh, heat weather record and then burn to the ground"},{"startTime":2641.326,"endTime":2646.885,"body":"the following day, I think."},{"startTime":2647.225,"endTime":2651.321,"body":"Um, but, uh, uh, it was, um, and, and it was also, you know, as"},{"startTime":2651.321,"endTime":2651.595,"body":"far as we could tell this in, in the observational record, this was a completely"},{"startTime":2651.595,"endTime":2655.965,"body":"unprecedented event."},{"startTime":2656.225,"endTime":2659.565,"body":"But interestingly, it was extremely well forecast."},{"startTime":2659.955,"endTime":2661.485,"body":"This is the forecast of the event."},{"startTime":2662.375,"endTime":2663.445,"body":"Color is temperature."},{"startTime":2664.025,"endTime":2665.725,"body":"The lines show you pressure."},{"startTime":2666.185,"endTime":2668.965,"body":"The forecast of the event three days ahead basically nailed it."},{"startTime":2669.905,"endTime":2673.725,"body":"Um, even the forecast seven days ahead was showing it was gonna be pretty hard."},{"startTime":2674.465,"endTime":2678.707,"body":"Um, and at 11 days out, again, you're seeing the, the broad, broad, you know,"},{"startTime":2678.707,"endTime":2678.99,"body":"this was a predict, this was a, a well predicted event, even a co almost"},{"startTime":2678.99,"endTime":2684.365,"body":"a couple of weeks ahead."},{"startTime":2684.745,"endTime":2689.355,"body":"And if we, even if we look, um, two months ahead, this is not forecasting"},{"startTime":2689.355,"endTime":2689.662,"body":"what was gonna happen on that particular day, but just looking at what could happen"},{"startTime":2689.662,"endTime":2689.969,"body":"in that season in a, in a, in a hot day in, in, in, in"},{"startTime":2689.969,"endTime":2699.805,"body":"the, in that season."},{"startTime":2699.825,"endTime":2702.805,"body":"And you can see it's, it's close to what actually occurred."},{"startTime":2702.905,"endTime":2707.951,"body":"So we're dealing here with a model that can, unlike many of the other models"},{"startTime":2707.951,"endTime":2712.325,"body":"we're talking about, actually capture the physics of this kind of extreme event."},{"startTime":2713.105,"endTime":2719.685,"body":"Um, we can convince ourselves even more of that by looking at, say, individual simulations."},{"startTime":2720.265,"endTime":2722.405,"body":"So that's what happened here on the right."},{"startTime":2722.835,"endTime":2726.805,"body":"This is one of the simulations in the model, which Nick has carefully picked out."},{"startTime":2726.965,"endTime":2730.245,"body":"'cause it, it, it is the one which is closest to what actually happened."},{"startTime":2730.305,"endTime":2736.0,"body":"And you can see it, it, it matches not only in temperature and, uh, pressure,"},{"startTime":2736.0,"endTime":2736.38,"body":"but also this lower plots show you the flow of water vapor in from the"},{"startTime":2736.38,"endTime":2736.76,"body":"atmosphere, uh, from, from the tropical Pacific, uh, which carried at this, this atmospheric river"},{"startTime":2736.76,"endTime":2737.14,"body":"that carried a huge amount of humidity into the Pacific Northwest, where because of this,"},{"startTime":2737.14,"endTime":2758.405,"body":"um, anti-cyclone, it didn't rain, um, but you had very moist air sitting over."},{"startTime":2758.825,"endTime":2763.507,"body":"So you had moist air, but not raining, which was sort of ideal conditions to"},{"startTime":2763.507,"endTime":2766.005,"body":"build up the, this really intense heat wave."},{"startTime":2766.905,"endTime":2770.915,"body":"So the experiment we did, or the experiment that Nick and Ancher did, um, uh,"},{"startTime":2770.915,"endTime":2774.925,"body":"with Chris Roberts also at the, uh, European Center, uh, for medium range weather forecasting."},{"startTime":2775.265,"endTime":2777.405,"body":"Um, you start with the actual forecast."},{"startTime":2777.545,"endTime":2782.097,"body":"So you're starting with a model, you know, could do the event because it did"},{"startTime":2782.097,"endTime":2782.401,"body":"it forecasted, and then they modified it, subtracting the pattern of warming that we believe"},{"startTime":2782.401,"endTime":2789.685,"body":"has occurred as a result of human infants and climate."},{"startTime":2789.785,"endTime":2794.135,"body":"And also changing greenhouse gas concentrations to something like 1900 conditions, and then doing the"},{"startTime":2794.135,"endTime":2798.485,"body":"same in the opposite direction and repeat the forecast to see what difference it makes."},{"startTime":2799.305,"endTime":2800.685,"body":"And here's the difference it makes."},{"startTime":2801.425,"endTime":2807.373,"body":"So you can see in both the future climate and the pre-industrial climate, we still"},{"startTime":2807.373,"endTime":2807.769,"body":"see a heat wave, but the loading of the dice is pushing us towards a"},{"startTime":2807.769,"endTime":2808.166,"body":"more intense heat wave in the red or less intense heat wave in the blue,"},{"startTime":2808.166,"endTime":2808.562,"body":"or conversely making the odds of a heat wave as large as what actually occurred"},{"startTime":2808.562,"endTime":2831.165,"body":"higher as a result of the loading and finally talking about work done last week."},{"startTime":2831.465,"endTime":2836.106,"body":"Um, and so, so this is, this is what our, our group does a lot"},{"startTime":2836.106,"endTime":2836.415,"body":"in, in, in, in Oxford, Olivia Vashti who's joining us, um, I haven't mentioned who's"},{"startTime":2836.415,"endTime":2836.725,"body":"funded different, different people here, but I will mention who funds Olivia because that's the"},{"startTime":2836.725,"endTime":2837.034,"body":"man group, uh, who actually based right near to Gresham College, they're, they're funding her"},{"startTime":2837.034,"endTime":2853.125,"body":"work and she's looking at precursors to what actually happened."},{"startTime":2853.125,"endTime":2857.696,"body":"So looking within, because you've got all of these simulations, I should have, each one"},{"startTime":2857.696,"endTime":2858.001,"body":"of these is a simulation of what could have happened given the starting conditions and"},{"startTime":2858.001,"endTime":2865.925,"body":"then all the modified starting conditions at the beginning of the forecast."},{"startTime":2865.945,"endTime":2870.303,"body":"So each one of these is a simulation with that complicated synthetic earth that I"},{"startTime":2870.303,"endTime":2870.885,"body":"showed you."},{"startTime":2871.305,"endTime":2875.005,"body":"Um, and so a huge amount of computing time goes into this sort of thing."},{"startTime":2875.465,"endTime":2880.702,"body":"Um, and what Olivia's doing is using the fact that we've got all these simulations"},{"startTime":2880.702,"endTime":2881.051,"body":"to ask what are the precursors to the event that happened, and can we link"},{"startTime":2881.051,"endTime":2887.685,"body":"those precursors to human influence?"},{"startTime":2888.185,"endTime":2894.155,"body":"So if you look carefully here, this is pressure, atmospheric pressure, uh, red is high"},{"startTime":2894.155,"endTime":2900.125,"body":"pressure, blue is, um, uh, low pressure and day see day there, day minus eight."},{"startTime":2900.125,"endTime":2902.205,"body":"That means eight days before the event that happened."},{"startTime":2902.585,"endTime":2908.18,"body":"And as I approach it, you can see it's about day minus six, a coherent"},{"startTime":2908.18,"endTime":2910.045,"body":"pattern appears in the Pacific."},{"startTime":2911.215,"endTime":2914.459,"body":"Maybe there's a hint of it on day minus seven, but it gets pretty strong"},{"startTime":2914.459,"endTime":2915.325,"body":"in day minus six."},{"startTime":2915.825,"endTime":2920.408,"body":"And then as I go forward, minus five, you can see it moves in there"},{"startTime":2920.408,"endTime":2920.714,"body":"strengthens, and there's the high pressure three days before the event when it was really"},{"startTime":2920.714,"endTime":2928.965,"body":"predictable, it was gonna be an intense heat wave and it builds up."},{"startTime":2929.545,"endTime":2933.895,"body":"And when you get to the heat wave, actually it's the, the, uh, bang on"},{"startTime":2933.895,"endTime":2934.765,"body":"the heat wave."},{"startTime":2934.955,"endTime":2941.815,"body":"This is, this is asking within that cluster of simulations what tells us it's gonna"},{"startTime":2941.815,"endTime":2943.645,"body":"be a hot one."},{"startTime":2943.915,"endTime":2944.205,"body":"Yeah."},{"startTime":2944.265,"endTime":2948.671,"body":"So that's, this is, this is the, the, the, the indicate the indicators within the"},{"startTime":2948.671,"endTime":2948.965,"body":"ensemble."},{"startTime":2949.265,"endTime":2954.032,"body":"So you can see that's clearly one of the triggers was a, a week beforehand"},{"startTime":2954.032,"endTime":2958.165,"body":"you had this trip pattern appear, blue, red, blue, and it moved in."},{"startTime":2958.165,"endTime":2959.165,"body":"That was clearly part of it."},{"startTime":2959.305,"endTime":2964.878,"body":"And another part was water vapor, water vapor transport, this, this carrying water in from,"},{"startTime":2964.878,"endTime":2966.365,"body":"uh, from the Pacific."},{"startTime":2966.635,"endTime":2968.365,"body":"This is a much noisier picture here."},{"startTime":2969.065,"endTime":2974.546,"body":"And you can see though, around day minus six do you see this bright, this"},{"startTime":2974.546,"endTime":2974.911,"body":"orange little feature appearing here, which strengthens going straight into the Pacific Northwest and it's"},{"startTime":2974.911,"endTime":2975.277,"body":"really getting strong four days before the event, but by the time the event happens,"},{"startTime":2975.277,"endTime":2986.605,"body":"it's all over."},{"startTime":2987.745,"endTime":2992.389,"body":"So it's not really, it, it's done, its work, it's loaded the atmosphere with moisture"},{"startTime":2992.389,"endTime":2996.725,"body":"and then the heat wave, and then we had the, the, the spectacular temperatures."},{"startTime":2997.865,"endTime":3003.545,"body":"So, um, to, to wrap up, um, there's a sort of, uh, there's a, there's"},{"startTime":3003.545,"endTime":3003.924,"body":"an appeal in this talk as well as just providing you with information, because we"},{"startTime":3003.924,"endTime":3004.302,"body":"can do this kind of thing, we can use state of the art weather forecast"},{"startTime":3004.302,"endTime":3004.681,"body":"models to actually answer the question of what is human infant climate doing to extreme"},{"startTime":3004.681,"endTime":3020.965,"body":"weather?"},{"startTime":3021.905,"endTime":3023.885,"body":"But it's not done routinely."},{"startTime":3024.515,"endTime":3029.645,"body":"This was a huge amount of work for a bunch of grad students in Oxford."},{"startTime":3029.645,"endTime":3032.125,"body":"Well one, one or two grad students in Oxford to be precise."},{"startTime":3032.585,"endTime":3038.227,"body":"Um, and of course got done years after the event because that's how long it"},{"startTime":3038.227,"endTime":3040.485,"body":"takes to get these experiments done."},{"startTime":3041.625,"endTime":3044.898,"body":"Um, you know, we're all being asked to do something about climate change and when"},{"startTime":3044.898,"endTime":3045.116,"body":"somebody asks you to, and you should point out to them, you know, again, I"},{"startTime":3045.116,"endTime":3045.334,"body":"I keep encouraging you to write your mp, one of the things you could ask"},{"startTime":3045.334,"endTime":3045.552,"body":"your MP is why don't, why aren't you doing a better job of telling us"},{"startTime":3045.552,"endTime":3056.245,"body":"what climate change is doing to us?"},{"startTime":3056.675,"endTime":3059.925,"body":"Because we could be, it's, it's only a matter of resources."},{"startTime":3060.225,"endTime":3065.262,"body":"We could be applying exactly the same models that we use for the weather forecast"},{"startTime":3065.262,"endTime":3068.285,"body":"to the question of quantifying, changing extreme weather risk."},{"startTime":3068.825,"endTime":3070.685,"body":"But we, we need to be doing this every day."},{"startTime":3071.025,"endTime":3071.965,"body":"We shouldn't just be doing it."},{"startTime":3071.965,"endTime":3075.375,"body":"You know, when, when one event happens in one part of the world and somebody"},{"startTime":3075.375,"endTime":3076.285,"body":"happens to get interested."},{"startTime":3077.345,"endTime":3082.085,"body":"Um, so, you know, we need to understand extreme and understanding."},{"startTime":3082.205,"endTime":3087.178,"body":"Extreme weather actually is, I believe the strongest case we have for developing virtual earths"},{"startTime":3087.178,"endTime":3087.51,"body":"for developing, um, computer models of our planet, which are, which behave in a way"},{"startTime":3087.51,"endTime":3094.805,"body":"that's actually indistinguishable from our, our real weather."},{"startTime":3094.905,"endTime":3095.805,"body":"And we are close to that."},{"startTime":3095.805,"endTime":3096.845,"body":"We, we have the tools to do this."},{"startTime":3096.845,"endTime":3100.805,"body":"It's not a, an an invitation to an open-ended research program."},{"startTime":3101.355,"endTime":3105.457,"body":"It's a matter of putting the, putting, putting pressure on, on, on politicians to foot"},{"startTime":3105.457,"endTime":3105.731,"body":"the bill for institutions like the med office, like the European Center for medium wage"},{"startTime":3105.731,"endTime":3106.004,"body":"rather forecasting to start doing this on a routine basis so that we don't end"},{"startTime":3106.004,"endTime":3116.125,"body":"up sort of speculating and arguing over these things."},{"startTime":3116.125,"endTime":3120.696,"body":"There's just an answer that comes out when a, when a big bad event happens"},{"startTime":3120.696,"endTime":3121.001,"body":"within a few weeks, we should just hear from our forecasting centers, yep, human influence"},{"startTime":3121.001,"endTime":3128.925,"body":"made that event less likely or maybe made that event more likely."},{"startTime":3129.025,"endTime":3133.685,"body":"And here's the number that that information could be available to you, but it's not."},{"startTime":3134.505,"endTime":3135.565,"body":"And then I think you should change."},{"startTime":3136.705,"endTime":3141.31,"body":"So wrapping up, um, we can quantify the impact of climate on weather by thinking"},{"startTime":3141.31,"endTime":3142.845,"body":"about loading the weather dice."},{"startTime":3143.505,"endTime":3148.405,"body":"Um, attribution of the most extreme events requires realistic models."},{"startTime":3148.865,"endTime":3153.243,"body":"If you try and rely on, you know, crude simulation averaging up from some, from"},{"startTime":3153.243,"endTime":3153.535,"body":"simpler systems because of the sand pile effect, you, you, you can easily get the"},{"startTime":3153.535,"endTime":3158.205,"body":"wrong answer."},{"startTime":3159.025,"endTime":3163.03,"body":"Um, and I believe this should be made part of the job of weather forecasting"},{"startTime":3163.03,"endTime":3164.365,"body":"centers to make this happen."},{"startTime":3165.015,"endTime":3165.445,"body":"Thank you,"},{"startTime":3172.975,"endTime":3173.325,"body":"Miles."},{"startTime":3173.325,"endTime":3173.805,"body":"Fantastic."},{"startTime":3173.805,"endTime":3175.725,"body":"That was absolutely fascinating."},{"startTime":3175.895,"endTime":3177.605,"body":"Scary but fascinating."},{"startTime":3177.745,"endTime":3181.176,"body":"I'm sure we've got heaps of questions, so we're gonna jump straight in if that's"},{"startTime":3181.176,"endTime":3181.405,"body":"okay."},{"startTime":3181.785,"endTime":3186.027,"body":"Now I've got a question from Paul who wants to know, we are talking about"},{"startTime":3186.027,"endTime":3187.725,"body":"how climate change is affecting weather."},{"startTime":3188.265,"endTime":3193.838,"body":"Is there, are there any reasonable studies on weather modification that could aid the negative"},{"startTime":3193.838,"endTime":3195.325,"body":"impacts of climate change?"},{"startTime":3195.495,"endTime":3198.487,"body":"We're gonna be talking about that in the final lecture of this series, so I'm"},{"startTime":3198.487,"endTime":3199.285,"body":"gonna pump that one"},{"startTime":3199.585,"endTime":3200.725,"body":"Sneaky promo there."},{"startTime":3200.915,"endTime":3201.205,"body":"Okay?"},{"startTime":3201.435,"endTime":3201.725,"body":"Okay."},{"startTime":3201.835,"endTime":3204.405,"body":"Alright then let's try this one from Andrew."},{"startTime":3205.025,"endTime":3211.783,"body":"Um, which is the greater insurance probability mega cities flooding or global food systems going"},{"startTime":3211.783,"endTime":3212.685,"body":"to drought?"},{"startTime":3213.025,"endTime":3215.828,"body":"Oh, well, now you've gotta ask that question for other people who work in this"},{"startTime":3215.828,"endTime":3218.445,"body":"spa in, in this part of the world who work in the insurance space."},{"startTime":3218.865,"endTime":3223.8,"body":"Um, but both of them are, I mean, it, it it's depends on the mega"},{"startTime":3223.8,"endTime":3225.445,"body":"city, depends on the event."},{"startTime":3225.515,"endTime":3229.325,"body":"Both of them are affected by climate change and they're the kind of things that"},{"startTime":3229.325,"endTime":3229.579,"body":"we need to know how those probabilities are evolving and at the moment, because we"},{"startTime":3229.579,"endTime":3229.833,"body":"need to know how to adapt to them and how to, how to, how to"},{"startTime":3229.833,"endTime":3238.725,"body":"deal with changing risks in the future."},{"startTime":3239.105,"endTime":3246.146,"body":"And at the moment, in my view, our planners are being underserved by the climate"},{"startTime":3246.146,"endTime":3247.085,"body":"research community."},{"startTime":3247.165,"endTime":3251.178,"body":"I mean, you know, I'm, I'm, I'm, I'm, I'm fessing up here that because when"},{"startTime":3251.178,"endTime":3254.925,"body":"we do these climate simulations, we're using models that just can't do these events."},{"startTime":3255.625,"endTime":3259.125,"body":"So what we should be doing is, and we've got bet much better models available"},{"startTime":3259.125,"endTime":3260.525,"body":"'cause we use them for forecasting."},{"startTime":3260.785,"endTime":3264.58,"body":"So, you know, we should be, we should be applying the best tools we have"},{"startTime":3264.58,"endTime":3265.845,"body":"available to address this problem."},{"startTime":3266.025,"endTime":3269.042,"body":"And, you know, yes, it would cost more money 'cause it costs computing time and"},{"startTime":3269.042,"endTime":3269.445,"body":"so on."},{"startTime":3269.705,"endTime":3275.617,"body":"But, um, you know, compared to the cost of preparing flood defenses or, you know,"},{"startTime":3275.617,"endTime":3279.165,"body":"preparing for a global food crisis, um, it's trivial."},{"startTime":3279.625,"endTime":3282.775,"body":"So we, we need to understand what's happening and we need to make the investment"},{"startTime":3282.775,"endTime":3283.405,"body":"to do so."},{"startTime":3283.585,"endTime":3287.812,"body":"And that touches on the question I was going to ask you, how prepared are"},{"startTime":3287.812,"endTime":3288.094,"body":"we as a society, as a culture, as an economy for living with a state"},{"startTime":3288.094,"endTime":3292.885,"body":"of sustained unpredictability?"},{"startTime":3292.985,"endTime":3295.965,"body":"And is the answer to that just to do more science?"},{"startTime":3296.985,"endTime":3302.973,"body":"So I've not talked about predictability in this lecture, and that would be a whole"},{"startTime":3302.973,"endTime":3307.765,"body":"other lecture about whether climate change is making the weather less predictable."},{"startTime":3308.105,"endTime":3312.586,"body":"That's a, you hear that a lot, but actually the evidence for it is, is"},{"startTime":3312.586,"endTime":3312.885,"body":"tougher."},{"startTime":3312.905,"endTime":3314.685,"body":"That's, that's work for the future."},{"startTime":3315.385,"endTime":3322.569,"body":"Um, so, but um, we are, we are having to cope with designing things to"},{"startTime":3322.569,"endTime":3324.485,"body":"deal with different climates."},{"startTime":3324.485,"endTime":3327.797,"body":"So if you're building a building today, it's gonna be dealing with a, a, a,"},{"startTime":3327.797,"endTime":3328.018,"body":"a range of weather risks in the early days of its life that will be"},{"startTime":3328.018,"endTime":3328.239,"body":"different from the range of weather risks that that building will experience at the end"},{"startTime":3328.239,"endTime":3335.085,"body":"of its life."},{"startTime":3335.345,"endTime":3336.845,"body":"So that makes things more expensive."},{"startTime":3336.865,"endTime":3339.605,"body":"It makes it harder for planners to do it."},{"startTime":3339.985,"endTime":3343.522,"body":"Um, and it makes it really important for people to understand how these risks are"},{"startTime":3343.522,"endTime":3345.645,"body":"changing, which is what this science is all about."},{"startTime":3346.365,"endTime":3347.085,"body":"A simple question."},{"startTime":3347.115,"endTime":3348.685,"body":"Most of my questions are very simple."},{"startTime":3349.105,"endTime":3354.65,"body":"Um, you're talking about the need for global coordination, uh, so we can predict better"},{"startTime":3354.65,"endTime":3355.019,"body":"what the future will be and whether it is due to climate change or natural"},{"startTime":3355.019,"endTime":3360.565,"body":"phenomena."},{"startTime":3361.345,"endTime":3362.965,"body":"Is there good communication?"},{"startTime":3362.965,"endTime":3365.725,"body":"Will a wa or do meteorologists work in isolation?"},{"startTime":3366.745,"endTime":3368.445,"body":"Um, that, that's actually a really good question."},{"startTime":3368.745,"endTime":3376.445,"body":"Uh, at the moment we have, um, so climate research, um, is remarkably nationalistic."},{"startTime":3376.945,"endTime":3381.645,"body":"So we have, we have national climate simulation programs that produce a climate model that"},{"startTime":3381.645,"endTime":3383.525,"body":"they've put together at the end."},{"startTime":3383.525,"endTime":3386.368,"body":"And, and that's a good thing in one sense 'cause it means you have a"},{"startTime":3386.368,"endTime":3387.885,"body":"sort of variety of models and so on."},{"startTime":3387.885,"endTime":3389.565,"body":"So you get to sort of explore uncertainties in that way."},{"startTime":3389.825,"endTime":3393.972,"body":"But to do this kind of thing, um, that's probably not the best way of"},{"startTime":3393.972,"endTime":3394.525,"body":"doing it."},{"startTime":3394.545,"endTime":3399.285,"body":"You're much better off pooling resources to get the best model you, you can."},{"startTime":3400.145,"endTime":3403.707,"body":"Um, and, and then all, because of course these models are global, you can't run"},{"startTime":3403.707,"endTime":3405.845,"body":"a model of just one corner of the world."},{"startTime":3406.125,"endTime":3410.165,"body":"I mean, so, so you, you may as well pool resources and do it."},{"startTime":3410.265,"endTime":3411.725,"body":"You might aren on just one."},{"startTime":3411.785,"endTime":3415.993,"body":"But, you know, uh, uh, pooling resources and having just a, a, a handful of,"},{"startTime":3415.993,"endTime":3416.274,"body":"uh, of, of these, uh, forecast models is the way to, which is the way"},{"startTime":3416.274,"endTime":3421.605,"body":"the forecasting community has gone."},{"startTime":3422.165,"endTime":3425.326,"body":"I mean, if you'd like, you can sort of almost tell that where the forecasting"},{"startTime":3425.326,"endTime":3427.645,"body":"really matters because it costs money when they get it wrong."},{"startTime":3427.945,"endTime":3432.508,"body":"So we've actually had a big winnowing out of forecasting, of, of forecasting centers over"},{"startTime":3432.508,"endTime":3433.725,"body":"the past 20 years."},{"startTime":3433.865,"endTime":3440.652,"body":"So we now have really only a handful of of countries maintain, um, full global"},{"startTime":3440.652,"endTime":3444.725,"body":"ensemble forecasting capabilities and other countries just buy in."},{"startTime":3445.225,"endTime":3450.233,"body":"So, so, and, and I think we need to move in that direction, or, or"},{"startTime":3450.233,"endTime":3450.567,"body":"rather, one, one option is that the forecasting community just adopts this and just applies"},{"startTime":3450.567,"endTime":3450.901,"body":"their approach, which is much more, you know, in, you know, global, uh, in approach,"},{"startTime":3450.901,"endTime":3463.925,"body":"uh, than is, than, than the way we're approaching climate issues."},{"startTime":3464.365,"endTime":3467.68,"body":"'cause climate, climate research has come out of universities, which is all, it's all quite"},{"startTime":3467.68,"endTime":3468.565,"body":"parochial and so on."},{"startTime":3468.825,"endTime":3472.333,"body":"And, and whereas this sort of stuff, it, it's, it's gotta be approached in the"},{"startTime":3472.333,"endTime":3474.205,"body":"same way that we approach the weather forecast."},{"startTime":3474.825,"endTime":3475.245,"body":"Hi there."},{"startTime":3475.685,"endTime":3480.245,"body":"I asked the question about the insurance risks that are predictable."},{"startTime":3480.755,"endTime":3481.045,"body":"Yeah."},{"startTime":3481.225,"endTime":3493.69,"body":"Um, but really my question is, can you use AI to enable a valuation of"},{"startTime":3493.69,"endTime":3497.845,"body":"halting deforestation and increasing forestation?"},{"startTime":3498.185,"endTime":3498.405,"body":"Yes."},{"startTime":3498.625,"endTime":3503.646,"body":"So, um, there, there's a, there's an enormous potential role of AI in this because"},{"startTime":3503.646,"endTime":3503.981,"body":"as Nick, uh, uh, is, is dealing with at the moment to, to tearing his"},{"startTime":3503.981,"endTime":3512.685,"body":"hair out with the terabytes of data you generate from these simulations."},{"startTime":3512.725,"endTime":3517.365,"body":"Because, you know, imagine we're, we're simulating the whole world at 18 kilometer resolution."},{"startTime":3517.735,"endTime":3522.126,"body":"We're doing it twice a week and we're doing 50 me, you know, there's 50"},{"startTime":3522.126,"endTime":3523.005,"body":"50 member ensembles."},{"startTime":3523.065,"endTime":3526.485,"body":"You know, it all builds up to ridiculous amounts of data very rapidly."},{"startTime":3526.825,"endTime":3531.01,"body":"And I think, you know, we all recognize that actually analyzing this properly will will"},{"startTime":3531.01,"endTime":3531.289,"body":"require ai and that would allow us then, if you've got a realistic in silico"},{"startTime":3531.289,"endTime":3531.568,"body":"model, so in a computer-based model of the climate, then of course you can ask"},{"startTime":3531.568,"endTime":3543.565,"body":"the kind of questions you are asking and you can then play around with it."},{"startTime":3543.665,"endTime":3546.279,"body":"You can deforest it and see what happens and see what happens to weather risk"},{"startTime":3546.279,"endTime":3547.325,"body":"in other parts of the world."},{"startTime":3547.905,"endTime":3551.805,"body":"Um, and, and, but you'll need to do multiple runs in order to do that."},{"startTime":3552.005,"endTime":3554.958,"body":"'cause you know, one, one run is never gonna, you know, because of the butterfly"},{"startTime":3554.958,"endTime":3557.125,"body":"effect, it's never gonna tell you everything you need to know."},{"startTime":3557.665,"endTime":3561.79,"body":"So that's where I think the first application of AI to this is just dealing"},{"startTime":3561.79,"endTime":3563.165,"body":"with the big data problem."},{"startTime":3563.915,"endTime":3565.565,"body":"It's more a comment than a question."},{"startTime":3565.965,"endTime":3569.055,"body":"'cause I, I live in Miami and we have hurricanes and they all have on"},{"startTime":3569.055,"endTime":3570.085,"body":"the pa on the news."},{"startTime":3570.085,"endTime":3572.245,"body":"They always have all the, the, the, the models."},{"startTime":3572.665,"endTime":3576.052,"body":"And I just wanna say that the, the European model is always the one that's"},{"startTime":3576.052,"endTime":3578.085,"body":"most reliable rather than, um, all the other ones."},{"startTime":3578.285,"endTime":3579.645,"body":"\u003claugh\u003e, we like to work with the best."},{"startTime":3580.155,"endTime":3580.925,"body":"I'll pass that on."},{"startTime":3581.225,"endTime":3581.445,"body":"We"},{"startTime":3581.445,"endTime":3585.811,"body":"Like to, on a positive note there ladies and gentlemen, join me for, to, for"},{"startTime":3585.811,"endTime":3586.685,"body":"thanking Miles Allen."},{"startTime":3586.755,"endTime":3587.325,"body":"Very, very much."},{"startTime":3587.355,"endTime":3588.245,"body":"Such a fascinating."}]}