 Thank you Good afternoon everybody It's a pleasure to be here. I'm gonna speak to you about sea level rise and Data science. My name is Andrew Ponell. I'm from the Hamilton Institute in Maneuth University So we live in a bizarre quandary at the moment where Data has never been more available the analysis techniques that we can use I've never been richer and yet Facts seem so sparse and thin on the ground. We seem to have so many disagreements And climate change seems to be emblematic of that problem You think given the size of the data sets and the processing power that we have Given that we've known about the greenhouse effect now for over a hundred and fifty years. This should be a Kind of a settled science and a consensus should be building But traditionally that hasn't happened We've spent far too much time arguing over over details of facts, which which are more or less decided now Having said that I've kind of noticed in the last few years that things have changed a little bit Certainly in the media things are getting much more sensibly reported these days and it kind of feels as though we've moved beyond that kind of controversy Issue and we're kind of Converging to making some kind of action about this this problem I'm not going to speak about climatology generally I'm going to speak about something which I know quite a lot about which is sea level rise and I'm going to start With it with a picture that comes from a paper from from 2011 where they It's just data. They just averaged all of the global tide gauges There's hundreds of them out there some of them go back 50 60 years Some of them go back a little bit further the details of how you average it is is quite complicated but what my research group do is They use Bayesian methods and lots of Gaussian processes to try and merge these kind of data sets together from multiple different sources and Try and estimate rates of change of sea level rise with uncertainty And so this is a global tide gauge data set goes back to 1880 the paper was published in 2011 But they updated it so we've now got data up to 2014 and you can see there in 1880 the rate was about 1.2 millimeters per year And if I set this graph running forward you can see that rate at the top there a sea level starts to rise You can see that rate changing 1.3 1.4 Millimeters per year and you'll see that it's not constant it goes up and it goes down And in fact if you start to average over the entire 20th century You get a rate of about 1.7 Millimeters per year and there's a little trick you can do in your head if you multiply that number By 10 that's the amount of centimeters you'll see in a century and that's often how people like to work with these So you can see it's around about 1.7 millimeters per year and then just before the year 2000 It starts to shoot up we start to hit two two and a half three three and a half four four and a half Millimeters per year so up to 45 centimeters of Sea level rise Across the century and that's a bit worrying and in fact the intergovernmental panel on climate change Think it's going to get worse than that because they think the the rise that That rate of rise is actually going to increase and we're going to see something between 70 centimeters and a hundred centimeters As by the time we hit the end of the century, which is a pretty pretty big problem but I Realize this talk is in the afternoon straight after lunch and everybody's starting to fall asleep and feel a bit sleepy So let's play a little game. There's a building in the center of this picture It's got a kind of serrated staircase type edge Does anyone know what that building is? Okay, I'll zoom out a little bit That building is still there. It's got a little bit smaller So don't know where we are We're in New York. Yes, if I zoom out a little bit further Building still in the center there anyone care to guess now what that building is It's Trump Tower Okay, Trump Tower most annoyingly is 14 meters above sea level So he is not about to get hit anytime soon By by sea level rise at least on Manhattan Island But then I discovered that one of the journalists at Buzzfeed had actually looked at all of Trump's properties and Had worked out which ones would start to be affected the soonest And if you remember from my two slides ago, you're getting about 70 to 100 centimeters That's about three feet and sea level rise and if you look at these very closely You see they all start to get affected once you get to up to about two meters But I think it's Trump Hollywood there that really Starts to get hit first So maybe at some point when it starts to hit his bottom line He'll actually change his mind about some of the science about this stuff Sea level science in the US is actually very well funded I have a number of collaborators who work over there and specifically in New York So we can do the same kind of thing that people do for the global tide gauges for but for New York And this is the graph that you get here and because we've had quite a lot of funding here We can combine satellite information. We can combine tide gauges We can combine more ancient information from from organisms which are stored in the soil Which tell us about past sea level as well. And so in New York We're actually able to go back over 1500 years. Let's try and work out what sea level is doing And again as I play this forward It's now going up every ten years you'll see this kind of like this average background rate of rise. It's almost always there This is an inevitable unfortunate fact about sea level rise because we're still coming out of the last glaciation because land level movements are still changing You will still see always this background sea level rise going on But as you start to get closer to the present as you see we're gonna hit about that 1.2 millimeters You'll start to see exactly what we saw in the in the global series as you start to hit into the 20th century you'll start to see it creeping up you start to hit above two millimeters per year and when we finish this study in the And I think the last rate is 2012 you can see we've already hit that three millimeters per year This is starting to accelerate as well The more recent information puts it at three and a half to four millimeters per year again Use your little rule of thumb that translates into 40 centimeters per century and the headline figure here is that there's 25 billion dollars worth of infrastructure below one meter above present sea level in New York So this is a really urgent problem and people are quite rapidly looking at this as it goes through This really the subtitle for this talk could have been a tale of two cities So we have New York which is a fascinating and interesting place to work on sea level rise But the other amazing city to work in right now is Dublin because almost nobody knows anything about what's actually happening To sea level rise in Dublin There's so much of our of the land around here, which is reclaimed from the sea which is very very close To sea level big chunks of the back of Trinity College are all on the sea level have all been reclaimed from the sea and Anybody who's who's been around Sandy Mount as well will Will have seen something similar So in the center of this picture Over towards the back. There is there is a little very ancient building called the pigeon house Which has a tide gauge in it and there's another one in Dublin port Which actually has a much longer record and people are just starting to look at that and again We can use the same methods as we go through the Dublin port tide gauge is absolutely crazy if you look at it So it's much more uncertain It's much noisier than the other ones and the kinds of rates of change you see as you go through are much greater So you see already in the early in the 50s in the 60s You're still getting three millimeter rises Then you're actually getting drops as you go down. It's going down to below seven millimeters per year But then again exactly like in the global series exactly like in New York You're starting to see just before the year 2000. It starts to go absolutely crazy It starts to hit rates and you'll see them as they come up in a second three five ten Thirteen fifteen millimeters per year and this is right on The spot where all of those wonderful fancy new buildings are being constructed left right and center Nobody really knows whether to trust this data set or not at the moment We don't really like doing stuff on just one tide gauge by itself. We like to have other information in there We like to have satellites. We like to have other stuff that's going on This is just one tide gauge and nobody's really sure if we trust it I'd be amazed if the sea level was rising in Dublin port at 10 15 millimeters per year But also I would be surprised if it's much less than three or four or five because that's what the global average is doing And we have a real problem in how we're going to maintain the sustainability of the city if that kind of thing is actually occurring So the government released its climate action plan 2019 It's a hundred and fifty pages long It mentions sea level rise four times and each time it just says sea level is rising Which isn't great luckily luckily luckily the individual local authorities have released their own climate action plan And if you read at least the Dublin City Council one, that's really good It's got it's the whole thing is pretty much about sea level rise Hasn't got a huge amount of solutions as to what they're going to do about it And they also call into question what's actually going on with this this Dublin port tide gauge Why is it rising three times faster than the than the global average? But there is at least hope that something might be done about this But having said that that's just about Dublin There's still so much we don't know the big global question right now in sea level rise Which we're all working on is acceleration. How fast is the rise in sea level rising? Are we going to level out by 2100 about a meter or is it going to be much higher? And there are all kinds of issues with this. There's the huge volumes of data We need data scientists. We need new methods to amalgamate those different data sets They all have different resolutions and different complexity. They're absolutely massive then you've got You've got issues with What comes with sea level rise as well so a 30 or 40 centimeter sea level rise doesn't sound that bad But what often happens when sea level rises is that the tidal range starts to increase as well And that means you get increased flooding and then if you get rainfall and storms when the tides are higher You get more increased extreme flooding as well And then you start to run into all kinds of problems and again because there's more energy in the system You end up with sediment movement as well And so this the the whole shape of Dublin Bay and can actually change This is all we know about Dublin. We have so little information about the rest of Ireland We really really don't know very much. There's a few other tide gauges knocking around the place We have some wave models. We have some satellite information But our job now is really to do a much better job So much of the natural resources and the amazing sites around Ireland are on the coast and we need to protect those So to finish off what we're working on is trying to just capture what the present state is in terms of Sea level rise and whether it's accelerating in the future We need to get that going the problem we have and this is where you can start to help and Advocate for us is in terms of funding We get small amounts of funding from the Marine Institute and from the Environmental Protection Agency But currently the largest funding source comes from Science Foundation Island and their remit from the government is to fund stuff Which directly impacts the economy and traditionally that has meant they have not funded much in the area of climate change Of all of these huge Science Foundation Island research centers Which are about none of them are really focused on on climate change And so for that we need people who work in companies Especially people who control budgets and especially people who work in big multinational Corporations who care about sustainability who care about this kind of stuff to nag SFI to put funding towards this kind of research So we can work out what is actually happening to sea level rise in the future and if you want to chat to me about that I'd be delighted. Thank you very much Thank you so much for that Andy there was a fascinating talk and Really quite a quite a pertinent topic, you know these days and really your message at the end there was quite significant and The funding does need to need to start coming in for for this kind of research So just a quick question. I have many questions could keep you all day But you mentioned that there is an innate background sea level rise Coming from the glacial period I'm just wondering like is it simple to quantify how much the human activity is actually Accounting for this sea level rise and that increase that acceleration that we see It's really hard because Sea level is it's a slow moving thing It's very hard to stop once it started and the contributions are from lots of different sources You've got just the amount of water in the ocean. You've got ice coming off You've got land level movements from from the last glaciations We kind of have a background rate of around one to one and a half millimeters a year Which is kind of the standard thing that most most corrections are taken off from the sea level rise So anything above that is usually ascribed to human influence We're at fault essentially. Yeah, okay. That's fantastic. We'll just thank Andrew again. Thank you. We're wonderful talk