"It's nice to be back here. I didn't know whether I was going to make it or not. I live now way down east Maine. I fled the foot of snow behind me and if I sneak back tomorrow I'll get there before the next one. I'm a marine biologist and I spent the vast majority of my career studying things that interested maybe 12 people in the world. I loved it you know because I loved biology and I loved ocean life. The spectacular beauty of it and the the puzzles of trying to understand it. But about oh my god I'm 72. So maybe 35 years ago I began to realize that everything I'd ever studied had disappeared or was on the way out. And that what I'd taken for granted as nature was something that my children would never see. So I became very involved in issues, I'd like to say deep issues of ocean conservation. But always from the perspective of the fact that for some weird reason I actually love the corals and the fishes and the sponges and the seaweed. When I gave a TED talk which has the the cheerful title of "How We Wrecked the Oceans". It was a kind of a lament for the extraordinary damage that we've done to ocean life. But around the last time I was here I started to realize that although most people sadly don't share my affection for sardines and jellyfish, they have a deep affection for themselves; and that the threats to the ocean life that I love are if anything more dangerous to us than they are to the natural life of the oceans. So, this is a very different talk. You know the last time I talked about over fishing, coastal pollution, climate change, poor corals dying, and all that stuff. You can watch it on your website. But this time I'm going to talk about all the human beings whose lives are going to be placed in very severe jeopardy. If you think about it the crises, the global crises that are going to be caused by these events that are going to play out (and that stuff sort of in your business). So let's start right out talking about sea level rise 101. I think this audience knows all this but you would not believe how many people don't know it and that's terrifying. Sea level is rising because ice melts when it gets hot and because water gets bigger when it's warmed. The reason the earth is getting warmer as you all know is because of emissions of carbon dioxide. So far as sea level rise has been mostly due to thermal expansion so about this much globally the ocean has risen as the water is expanded as it got warmer. But you know at this point it's really most about melting the ice on the land and god only knows there's a lot of it. None of this is controversial. It was predicted by a guy I once met and I spelled his name wrong. It wasn't good stuff it was his father Svante Arrhenius who predicted exactly what would happen in his Nobel Prize speech in 1896. So this isn't exactly news. Sea level is rising a lot faster than we thought it would. Which is the really sort of scary part. It only rose about seven to eight inches in the last century. It's done more than that really pretty much up to now. The Intergovernmental Panel on Climate Change, an international UN group of distinguished climate scientists, makes projections every few years about how warm the earth will get how much sea level rise. There's one thing you can say about them they are consistently conservative; they always get it wrong. They've done so many IPCC reports that it's P less than 0.05 statistically that they will underestimate everything. You see that for sea level rise. The solid lines from the top are the real data all the lines below and the gray stuff. The confidence interval is the projection of the IPCC. These people have been screamed at for being radicals. They're conservative they're always too conservative. Sea level is growing, is rising faster and faster. Because what's going on is when we want off the earth. It's not just the temperature. We set off all these chain reactions of events. For example it used to be in the summer...you know the Northwest Passage...for hundreds of years nobody ever managed to sail across the Arctic Ocean in the summer. Now it's sort of a passe: 'oh you can do it and sell tickets'. The ice is melting really really fast and it's melting much faster than anybody realized. We understand now why it used to be the ocean the Artic ocean was always white in the summer with the snow on top of the ice and it reflected back the heat but now there's all this melted ice and sea water below it. The seawater looks black and absorbs more heat instead of reflecting the heat that the snow used to do. So that heat which is absorbed warms the water even more. Which means it gets warmer faster which means more ice melts which means there's more black surface which means there's more heat observed absorbed and bla bla bla bla bla. Before you know it there won't be any ice there in the summer in 20 years. Then the other thing which is actually like a horror movie is that methane gas is bubbling out of the permafrost and the lakes and the sea floor of the Arctic Ocean. Methane is 30 times stronger as a greenhouse gas than CO2. The thawing soils are getting warmer because there's more methane which makes it get hotter which mean there's more and more and more. These are 'positive feedbacks' and they are a real pain for climate modelers. They make everything nonlinear. But here's what it looks like on the left. You can clearly see black and white the more black the hotter it gets the more white the cooler it stays. The white is on the way out it's going to get hot and that will be irreversible. Then on the right you see in an Arctic like this methane gas just bubbling up continuously. You can light a match to it ... you got to have it be a stove ... it's just coming out all the time in these vast quantities. It's just going to keep doing that and then that's the disappearance of the ice in the Arctic Ocean. There won't be any there very soon. Ok so these positive feedbacks drive the modelers nuts because it's all about very complicated nonlinear dynamics. Really difficult mathematics. We keep we empiricists ... boring empiricism as opposed to the modelers ... we keep finding new feedbacks and then they have to go out and try to figure out how to incorporate those into their models. As I said before, the IPCC scientists were not alarmist they were too conservative. That's really bad news for half the population of the United States of America because we lost 20 years that we could have been doing something about this. So how much will sea level rise. Certainly as high as the naval base at Norfolk and in San Diego where I used to live. You guys are going to have to move. The latest IPCC projection which is very conservative is for about one to three feet. But what's really bizarre about this latest report is they say we're [not really] confident that it will be within those limits. That's just bizarre for modern science because what you're saying is there's one third, one in three chance we don't know what we're talking about. It could be bigger. That's the thing we should be worried. Because a one in three chance of a terrible outcome is a really bad thing. I think this is really interesting about all environmental problems. You know ... you don't like your face ... [so] you go to a plastic surgeon. You say 'fix me' ... the guy says well you know there's a 1 in 10,000 chance that you might die. You say I like my face right? Or you put your kid ...your kid goes out to walk to school and somebody tells you there been a lot of accidents lately...'there's a 1 in 10,000 chance your daughter will die walking to school'. You would not accept that. You go out and hire somebody to be at the crosswalk to walk your child to school. That common sense has not penetrated anything about the environmental policy of this country or any other country in the world [concerning global warming]. It's time to catch on. So why is confidence so low I mean it's we're really smart we've got these satellites we've got all this stuff how can we be so wrong or so unsure? The problem is Greenland and Antarctica; 80% of all the fresh water in the earth is locked up in Greenland and Antarctica. If Greenland melted tomorrow's sea level would be 23 feet higher. Oh ok all of Antarctica will probably never melt but if it did it might be a hundred feet higher. Okay it's very unlikely that all of Greenland is going to melt in the next hundred years. Very very unlikely, which is good news right? But it's incredibly worrying that there are rivers and I mean rivers of meltwater pouring off of Greenland twenty-four hours a day. The West Antarctic Ice Sheet (and maybe a bunch of you in this room have been there) it's absolutely beautiful beautiful place. You know sort of down around the Antarctic Peninsula that ice sheet is unbelievably unstable. It's moving, it's bending, it's burping, it's not happy, and my friends who go down there on cruises they come back and I say Jeremy you would not believe what's going on down there. When it breaks ... it will break ... it will break suddenly not gradually. It's not like Greenland with a mile thick pile of ice. The West Antarctic Ice Sheet has its feet in the bathtub. That was fine as long as it was frozen all the way down to the ground. But now water is getting in underneath. So it's gonna happen and when that happens it'll happen fast and we'll see ten-foot sea level rise in a few years and we ain't ready for them. I think we've got a few decades but but certainly no more than that. So there are a lot of people who are saying the hell with the IPCC we're just going to do it. This is an example of that. This is a very good paper. There are others. What it shows in the graph is the distribution of probabilities of a particular sea level rise. It's still the case being conservative that the peak and probability is somewhere around 70 centimeters. But look at this, look at this broad tail out to two and a half meters. We call this kind of skewed distribution fat-tailed in the jargon of Statistics. This means that there's like a 5% chance of something really really bad happening by 2100. We could all say well there's a 95% chance that that won't happen, but think about your kid walking to school and then that's not a very acceptable way to think about it."
[the video below is longer than the above transcript excerpt of it is].
The next post in this series is here, previous post in this series is here.
Video of a War College presentation by Jeremy Jackson (from which the computer generated transcript above was taken):
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