How Close Are We to a Climate Change Tipping Point?

this next session is about tipping points as most of you know our climate is dangerously close to points of no return moments when nothing might ever be the same again once certain thresholds or tipping points are crossed chain reactions caused by an accumulation of small changes will shift our climate irrevocably but what exactly are these tipping points and if they occur over decades or centuries could we cross them without even noticing what are the extreme risks that they are already perpetuating and how can we avoid the worst impacts those are the questions that we will be discussing um with two of stalwarts of research on this field uh people that we at the New York Times reach out to for knowledge for comment on these issues Dr Johan rockstrom who's a director of the pot Sam Institute for climate impact research and Dr Hassan Lee who is the chair of the intergovernmental panel on climate change we'll also be joined by my colleague Ray Jung in New York who is the New York Times in-house specialist on climate science so with that um I will invite our speakers up to the stage so we can begin our discussion we often think of climate change as linear we add a certain amount of greenhouse gases to the atmosphere and aspects of the Earth's chemistry respond in a certain way by a certain amount it becomes hotter by a certain amount storms contain more water by a certain amount snow and ice melt by a certain amount these aren't changes we want to see but at least we have a decent grasp on the magnitudes of cause and effect tipping points are very much not linear once we cross them even by a little bit big changes can happen abruptly and reversibly they gather speed on their own coral reefs dying on mass ice sheets collapsing not just melting little by little huge ocean currents getting thrown off course once we cross the Tipping Point what seems like just another little increment of global warming sets off a sequence of events one that stays in motion even after we reverse that little last increment of warming changes in the climate start to run away from our ability to do much about them scientists like Dr Lee Dr Rostrum rockstrom have been thinking about these tipping points for a long time how far away are they how catastrophic that they be which climate events even have tipping points and how might different tipping elements interact one tipping the other tipping another there's been a lot of interesting work on all these questions and scientists are gaining confidence in their predictions reducing their uncertainties I just wanted to highlight a few recent findings some of it I think is is good news at least in the scheme of things scientists have become more confident that certain changes aren't irreversible or self-perpetuating Arctic sea ice can reform to some extent areas of permafrost can refreeze although of course the carbon that's released when it falls doesn't go back into the Earth uh for other events The Tipping Point seem slightly farther out in the future than was once believed these would be for instance the die-off of the boreal forests or a shutdown of ocean mixing in North Atlantic and other climate patterns that scientists once thought might shift abruptly after a certain point now don't really seem to have a clear Tipping Point a collapse in the Indian Monsoon for instance or a more persistent El Nino those can just keep shifting and shifting gradually which may not actually be very good news of course that still leaves us with several really high impact events that could begin on a dime and cause damage that scientists believe will be irreversible for centuries even millennia and some of these like the loss of the West Arctic ice sheet might already have begun so I'll turn it back to you Max and hope you have a good discussion thanks Ray um I think something that Ray just said for us there was you know in addition to kind of walking us through what we do and don't know is is introduce us to that there are many tipping points not just one and and so on that note I'm I'm I think I wanted to start with you John um about how we should understand this science you know is um is kind of addressing and avoiding these tipping points more about uh the kind of goals that we hear so much about at cop which is about limiting global average temperatures to a certain amount of rise or not or are there targeted approaches um you know depending on what Tipping Point we're talking about or is it some kind of mix of those two things yeah thanks Max and let me just kind of follow on on Ray's really good summary here to come to your answer so to begin with what what is uh why are we talking about tipping points well let's say we push so-called tipping elements across their biophysical thresholds which leads exactly as Max says to shifts and feedbacks which means irreversible change and what we mean by a tipping element is a biophysical system that fulfills two criteria criteria number one is that we have scientific evidence that it contributes to regulate the state of the climate system and the second criteria is that we have scientific evidence that they have multiple stable States so it can be either a frozen ice sheet or a liquefied ice sheet or a rainforest or a Savannah and what separates these states are the interactions and feedbacks so these are non-negotiable biological chemical physical properties of these systems so if you have a healthy ice sheet with very high altitude it's very cold if that starts melting and it gets lower lower altitude you get a self-amplifying feedback because the lower the altitude the warmer it gets the darker the surface gets because it gets liquefied and Albedo shifts and at a very precise point it goes from self-cooling to self-warming so in all Tipping Point research we're always looking for these two criteria does it control the climate system and does it have multiple stable states with feedback Dynamics that's why as Max says as Ray says there's been a lot of science here even even excluding some systems that we thought were tipping elements but that actually don't show this Behavior like the monsoon system like Arctic sea ice but now we've come a long way the first Tipping Point science was published in 2008 we've done done several updates and in 2029 we had the final update and the last one came just six weeks ago where we for the first time did a full scrutiny and coming up with the analysis that we have 16 of these tipping element systems that fulfill the two criteria and and assessing these very careful in terms of their temperature thresholds they align by the way very well with with the ipcc6 assessment that in table 4.10 in working group 1 has the first time the table of the Tipping element systems but not providing temperature thresholds on them we do the first attempt of scientifically putting temperature thresholds showing just like Ray says that a number of them are at risk already today actually at 1.5 degrees Celsius at the green ice sheet the Western antarctic ice sheet tropical core Reef systems and abrupt throwing of oil permafrost are likely likely to cross the threshold that's a very strong scientific statement but then for example the Amazon rainforced to come to your point about about multiple interactions the Amazon rainforest we assessed in terms of temperature is at risk at Beyond two degrees Celsius so a bit of a positive message there more resilient than we had thought but then when we discussed this with the ecological scientists they tell us you know what you have to factor in deforestation as well because the ecological undermining of the resilience may pull down that temperature threshold even further so Carlos Nobles leading Brazilian scientist who's here at Copp he says that already at 20 deforestation combined with 1.5 could push us across the Tipping board but the science is still unclear there so yes it's complex it's about interactions between by biology and physics but I think we're coming made major advancements to get much better Precision on on when when are we at risk and we're approaching that risk very soon oh Dr Lee I wonder if you can help us understand what role the ipcc plays in in studying these phenomena and and before this we were talking about you know what's known and what's not known and and I'm wondering if you could talk more about that too thank you thank you very much for inviting the ipcc in this uh in this forum uh before I answer to your question specifically uh just to give you some of my understanding of the Tipping points from a economist and uh from that point uh this morning I was when I was eating breakfast I saw outside there was outside a pool and the pool was equipped with a water slide so there's a stairs going up to the top and then some plateau and then water slide the kids were enjoying that water slide and I saw that this sort of configuration was very much looking like a net zero emissions pathway but at the same time the kids were enjoying jumping from that both then downslide and that looks like a perfect example of passing the Tipping Point once you pass that point there's no turning back only way is going down to the water pool and the kid knows where is The Tipping Point I I thought that we do not know where the Tipping points or this climate events and scientists as Johan explained scientists are working very hard to narrow the uncertainties about where and how serious is tipping points are the ipcc does is a a platform to engage a scientist physical scientist as well as ecology and also science social science economics and other relevant disciplines to answer these creative questions of climate systems changes in the climate systems and its impact on human and natural systems and the ways to respond for a liveable future and thus we have just finished day three working group reports and the synthesis report that will be available next year well maybe we can bring that back to you then um Johan the I kind of want to come back to the idea of there being targeted approaches even if there is some uncertainty about exactly what constitutes a Tipping Point and when we're close to hitting it and what contributes to it seems that even in that process there must be some discussion of what are the best mitigating tools um and some of those May differ depending on the many different scenarios that you laid out um yeah I know that's that's actually true and um and I should just add one element before coming to exactly what those tools are and what approach I would advise us to take because it's just like what song Lee says I mean we're doing so much effort in advancing the research on tipping points but they're complex and not only are they complex in in their own individual analysis they also interact between among the Tipping points themselves and Ray pointed that out that we have Cascades between tipping element systems so for example what we are now showing is that when the green line sheet which is one tipping element system melts very fast it releases cold fresh water into the North Atlantic this slows down another tipping element at the a mark the Atlantic Meridian overturning circulation which has slowed down by 15 is a thermodynamic engine which is driven by really heavy saline water that flows from the Southern Ocean at the surface releases heat up in the Gulf Stream and then thanks to the bottom and flows back and it circulates in the North Atlantic but with fresh water it dilutes the weight the density goes down the engine slows down and the hole overturning slows down that pushes the monsoon system further to the South impacting on another tipping element system the Amazon the Amazon basin gets less rainfall more drought more fire releases carbon and comes closest to its tipping Pawn but it also locks surface water heavy saline surface water in the Southern Ocean which can explain why the Western antarctic ice sheet another tipping element is melting faster than science had predicted these Cascades is at the scientific Frontier not yet reported in the ipcc but what does this mean for your question well in my mind it must imply precautionary principles because science will never get the exact I mean it's like the kids on the slide there's an exact point we know it it's just like our body temperature is also Tipping Point you know we know that at 42 degrees Celsius we tip over from one very desired State living to another not very good State die and and that's a it's trial and error that has taken us to that point but do we ever act on the 42 degrees Celsius of course we don't if anyone in this room approaches 39 we go home and go to bed that's precaution we've learned that trial and error and that is what I think we should apply also for the Tipping Point system so Tipping Point science is actually the most important scientific guide for the planetary boundary research when we quantify the planetary boundaries we use Tipping Point science to help us place the boundary the safe boundary so safe boundary on land and water and carbon are Guided by Tipping Point science we have uncertainty ranges the confidence intervals that we've learned from the ipcc by the way the red Embers diagrams and these help us to define the the safe position and and I always argue that we should place that at the lower end of the scientific confidence range because that's the precautionary prone go beyond that point and we enter this slippery danger zone where things can happen but we cannot get the exact number those kind of cascading effects that Dr rockstrom is describing seemed to be to me at least kind of one of the most Crystal Clear explanations of the urgency of all these talks around climate change um you know our systems are interconnected and understanding that more scientifically is is the key to acting on them and so Dr Lee I'm wondering kind of with the ipcc providing such a basis for understanding and ultimately for others to act whether those are scientists or governments what is the what is the kind of future of research on tipping points that that the ipcc is undertaking you know uh the theme for this cup cop for implementation and uh I think this is a very uh substantive meaning to that and then I remember that this isn't the first time first Hub that used word implementation as a main theme and uh 2017 we had a Fiji born Hub at that time the theme was the momentum for implementation and 2017 that was the year that one year before the Special Report the 1.5 made available and after that there's ipcc report 1.5 and the special report on the land the special report on the oceans and Christopher and then three regular reports that regulator was completed in 2022 so I counted that from 17 2017 to 2022 to five years and it took what six ipcc reports to drop that word momentum from the implementation so I wonder you know that's probably the ipcc will do these assessments regular plus some special reports within the next five years and then after five years what will be the theme for the car and hopefully we hope that it will be the same that cup for celebration hopefully celebration for one celebration the global peaking of emissions indeed occurred before that year that would be marvelous and I think that this Tipping Point certainly should start from our understanding of the natural system but I also want to say that there is it should be a Tipping Point in the social system and in this report ar-6 booking group three can I be specific report clear indication that there are tipping points that in the society so that once that critical point passed then we society as a whole will go for a certain direction and I mentioned about this order slide and I believe that the if we invest correctly correctly means that investing in the lower carbon assets and then it will create some kind of a past dependency now therefore society as a whole will slide down to the net zero now to have that tipping points we must have for the world as a whole a speaking of global missions as soon as possible and as you know very well right now the mission is decreasing and uh so let's wait when let's see when that Global peaking will happen I'm oh I'm hoping that such picking will come to us as early as possible well thank you for for bringing us to the idea of a social Tipping Point um that was going to be my last question before we throw it out to the audience for for theirs um do you think Johan that the urgency of this is is conveyed well enough in in the media or even within the scientific community and and at what point do we see a social Tipping Point where perhaps there's some kind of realization that of an impending feedback loop that can't be reversed where that idea takes hold not just in an individual's mind but in a society is collective sense of purpose well and and the following I I really don't say because we're sitting in a New York Times event but but I would really congratulate New York Times if every citizen in the world read the New York Times they would be very much on top of the fact that we are in the midst of a climate crisis or you could read the guardian or you could read The Wall Street Journal even though you could read you know Washington Post you can read so many of the of the mainstream media the problem is that we're still not reaching out to all the Isles politically or or citizen-wise across the world that is a continued challenge but I would say that the scientific Community is today I mean in my professional career I've never felt that there's been such a strong momentum and consensus there's never consensus in science but the message is really clear we're we're facing serious risks and we need to as hosung Lee points out bend the global curve of emissions very fast in fact if you look carefully at the ipcc assessment from the 1.5 report but already in the ar5 most scenarios that takes us to a safe landing well below two and can land at 1.5 they Bend 2020 actually so so it's uh every year now puts us not only at risk for undermining and Crossing tipping points but also undermining in terms of rising climate extremes but the budget shrinks so much that we are already today at the requirement of five to seven percent emission reductions per year to have any chance of staying within the carbon budget and you know we're increasing by one to two percent per year and we know that you know if you go beyond five percent you're talking about energy Revolution Pace I mean it's not easy to how you can keep the economy running while at the same time do that pace of transition so I would say that it's well understood today that it is an urgency apart from those stakeholders that still most of them not being denialist but most of them just sitting status quo on the fence and kind of hedging their bets still on on where will this move over the next 10 20 years and I think what we need to do is to show that it's clearly moving in the direction of decarbonization you don't want it left behind on that on that transition okay I think we have time to pass around a mic for some questions hi so my name is Waleed Mansour I'm from Egypt and I have two questions one for Professor Johan and one for Professor Lee and my question to professor John is do you really believe it's a matter of Finance to solve the crime of Crisis so if the money is there we know it is is that the only problem we have that's not a cynical question and my second question to you Professor is regarding since you spoke of the social aspects do you think that environmental reform can happen in absence of democratic institutions whereby scientists are free journals are free people can speak and complain thank you victims right yeah thanks for that so so Finance is really really important but I would argue that it's not the only question that needs to be resolved for a for a transition a fast transition Finance is important in several ways I mean one is that we must immediately stop the 500 billion US dollars per year of direct subsidies for fossil fuel use or the five four to five trillion US dollars in in implicit or indirect subsidy so that has to stop and then we have to and then we have to you know get all the financial institutions from Pension funds to asset manager to private Banks to to completely halt all financing of new fossil fuel infrastructure I mean from Norwegian oil exploration to new gas fields to Coal Fire plants in China that that that has to stop so that is finance really critical and the third one is of course to put the investment and help developing countries to accelerate their decarbonization patterns to help developing countries to to to be able to move away from often very cheap state-owned fossil fuel resources to be able to scale up renewable energy sources but will all that be enough I would argue that the answer is no because we also need the Innovation and Technologies we need the social tipping points to occurs and you get a much more Equitable sharing of the remaining carbon space how to do that when we're over consuming carbon in the north and under consuming in the South so there are much much more elements to with and only finance yes I I think I probably not heard well about your question I understood that your question is about what the society can do can the society can do to resolve this question if we don't have Democratic agenda all right very quick questions let me let me emphasize this the climate change issue and well in fact all other environmental issues is the problem of how to deal with what is known as so-called externality it is the area that market system do not properly the address cannot properly address now that means that government has to have a clear role in resolving these questions now for climate change issues as you know very well it is a it requires a collective action Collective means that all Nations in the world and thus we should not have such thing as a free rider in the mitigation effort now is that easy and that's the reason why Nations meet regularly to have a common solution common action now there are certain parts of the segment of society who does not really believe in the role of government and uh you know I don't question the uh they are the world view or their philosophy of that role but clearly the science and may say that economic discipline indicates that there is a definite role for public sector government to play to resolve climate issues to resolve environmental issues and without that leading role by the government I don't think we will ever able to resolve this climate problems the reason is very simple everyone mentioned very well about this investment questions and you know the biggest uncertainty in the investment decisions also investment that we need to have in this climate stabilization is uncertainty on the part of government policy uncertainty is the greatest uncertainty that the real world decision makers has to have now I think that's a tragedy government is supposed to be a entity to give us the leading role in this solution of global public goods problems so we keep trying and uh we need to have a some sort of mechanism that would give us a very clear link between the pursuit of global public good and the decision that will be made by us individually and locally so that every one of us makes decision on the basis of his or her best interest but in the end when when it was aggregated we'll find a outcome that is that would be comparable with the achieving of that Global public good at this moment we do not have that link and the reason governments meet so often is that to establish that link between Global pursuing Global public good and individual decision making process hi my name is Samuel Rubin and I am a social impact producer and a climate Storyteller so I really appreciate that today's session started with a storytelling moment so my question to you and the scientific Community is how do we collaborate with cultural strategies with storytellers with Communicator to make sure that your scientific findings enrich the general mainstream audience and how do we do that Beyond The Apocalypse Beyond despair because unfortunately not a lot of people report there are hundreds of pages with a lot of scientific language and I wonder if you feel that your work is actually rich in and the people are understanding how close we are to the Tipping Point I actually had a similar question to that and I'll kind of add my version if I hope you don't mind which is you know maybe you can also both of you could paint pictures for us of of where we're going right now and and maybe do a bit of your own storytelling in in that sense um I think you know I think that that'd be a great thing to leave people here with is is a sense of of what you think about actually physically when you think about tipping points well let me just in a way some summarize it party to it's not a defense point but I think it's quite important to recognize that science is science and we're not the best communicators but I don't think we should be expected to be the best communicators I think we need to hold hands and work with the communicators we need to help each other here ipcc is just the most phenomenal institution the world has I mean it's just fantastic to have this scientific floor to stand on for all our policy making for all our communication for all our work but ipcc cannot do it alone I mean IPC has done tremendous improvements in communication I mean I don't know if you've seen the ipcc AR6 summary for all it's just fantastic I mean I was really congratulating for that I mean just read it through it's just a phenomenal way of just communicating to every citizen in the world with the ipc6 assessment says but painting the future well you know there are two Futures one future is of course the dark future it's a future where in just 50 years time three billion people will live in regions that health-wise are so hot that the vulnerable people will be on the Move will have forced displacement 1.6 billion already today live in such teachers so we are at risk of having you know people's movement food insecurity displacement social conflict you know just Amplified droughts floods disease storms simply a world that is less and less livable for All Humans but if we act and if we're able to bend the curve but also come back within the planetary boundaries we have just a sliver of a chance to have a future where we're not only able to maintain planet Earth at the state that we are in roughly as today but also a future where we have so much evidence today that health-wise security wise job-wise life expectancy but also in terms of jobs economy Innovation is a much more advanced much more attractive much more Equitable you can just think of the energy Independence in most countries that do not sit in the hands of autocratic war-mongering dictators like Putin it's quite a desirable future if you just amplify the pace to decarbonize so that is of course what leads the youth movement today to the double frustration we have the risks but we also know that the future is brighter if we act and that is a double frustration if we're not acting so I think we exactly as you say like we need to paint more clearly the the future in in a way that can be visibly shown but I think we need help there to be honest I don't think we as academics are the best place to do it we can give the the pieces to it but we need help in painting well thank you for that um and and thank you both for sharing your thoughts it was an honor to have two great thinkers like you on this on stage but I'm afraid our time is up and we'll be moving on to the next session so but thank you again [Applause]

Channel: New York Times Events

Views: 23,188

Keywords: nytcf, the new york times, climate, events, climate forward, nyt, nytimes, live journalism, live event, livestream, climate change, cop27, sustainability, international, global, united nations, egypt, sharm el sheikh, cop

Id: mFYE4CfeIj0

Length: 34min 40sec (2080 seconds)

Published: Tue Nov 08 2022