Henry Pollack: “A World Without Ice” | Talks at Google

>> Welcome. On behalf of Green Google and Authors at Google, it is my privilege to introduce Dr. Henry Pollack today. With his colleagues on the inter-governmental panel on climate change, Dr. Pollack shared the 2007 Nobel Peace Prize with former vice president Al Gore. Dr. Pollack has been a professor of geophysics at the University of Michigan for more than 40 years, and has conducted scientific research on all seven continents. He now serves as a science advisor to Al Gore’s climate project. Dr. Pollack is here today to talk about his latest book, “A World Without Ice.” Following the talk, we’ll have a Q and A session. And please remember our remote audience at that time, and use the microphone in the center aisle when you’re asking a question.

And with that, please join me in welcoming Dr. Henry Pollack. >> [Clapping] Dr. Henry Pollack: Hello, everyone. Thanks very much to Google for the invitation to come and talk about my new book, “A World Without Ice.” I know there’s a lot of excitement on the campus at this very moment with Secretary of Energy, Steve Chu, announcing the ARPA-E, new energy grants that are going to play a big role, we hope, in mitigating the effects of climate change. The introduction by your president just a few moments ago over in the other auditorium said that, Steve Chu is, you know, someone who — you know, some guy with a Scandinavian accent called early in the morning one day — and that, of course, was the reference to the way in which people learn that they have won the Nobel Prize. As you just heard in the introduction that, the 2007 Peace Prize was shared between Al Gore, who had half of it, and the Intergovernmental Panel on Climate Change, which I’m a member, got the other half. So people said, “Did you get an early-morning call from Oslo? Or Stockholm?” And I said, “No, but I did get one from New York.

” And they said, “What was that about?” And I said, “Well, it was a — kind of a faux, Scandinavian accent, and it took me about maybe ten seconds to recognize that it was my son calling. He had just heard about the IPCC winning the Nobel Prize on the radio, and he wanted to be the first to let me know. So there he was in his best Norwegian accent, [imitating accent] “May I speak to Professor Pollack,” and such. So that’s how I learned about the Nobel Peace Prize. And I’m sure that Google has lots of Nobelists, but maybe not two in one day within an hour. And so, it’s a pleasure to be here. Let me just say a little bit about myself, and then we’ll get to talking about the book. I’m an Earth scientist: geologist, geophysicist, climate scientist. And I teach at a university, and do research in wonderful places around the globe. And I’ve found that it’s been a hard sell persuading the public that climate change is real and that humans are playing a big role in it.

These two facts — that climate change is real and humans are playing a big role — are very apparent to the scientific community. And yet, there’s about half of Americans who don’t believe that it’s happening, and certainly don’t think that people have anything to do with it. And so, I’ve — in addition to my scientific work — have tried to reach out and help people understand the realities of climate change. And part of that work has been working with Al Gore — who, I understand is going to be here in just a couple of weeks with his new book, which I had a chance to read and draft for him about a month ago. But, I have been working with Al Gore in his climate project, which is a project that is designed to train community volunteers to go out into their hometowns and talk at schools and churches and rotary clubs — whatever audience they can pull together — and talk about climate change.

And so, I’ve been helping him in this training program of bringing people to Nashville, that’s Al Gore’s hometown, and a long weekend of intense activity. We send them back, and they become “climate messengers,” as we call them. So, in that context, I’d also written this book called, “A World Without Ice.” And the book is about ice, climate, and people: the role that ice has played in the development of our landscape, in the development of Earth’s climate, and its effects on human civilization, and the reciprocal impact that people are now having on ice. A theme interwoven throughout the book is, Earth’s changing climate, both in the past, present, and in the future. Now, why ice? Why did I choose ice as a vehicle to carry the story of earth’s changing climate? There are three principle reasons that I like ice.

The first is that, ice plays a big role in Earth’s climate system. In the polar regions where you have these big expanses of white ice, basically, ice is a very good reflector. Snow is too. And if you’ve been skiing, you know you run the risk of getting sunburned, not from the sun coming from above, but from the reflection off of the snow from below will give you a lot of radiation. So ice is a very good reflector. And, as a reflector, it takes sunshine — that would otherwise warm earth — and sends it right back to space without it doing any warming at all. And so, the more ice there is, the less sunshine Earth receives to warm it; and, the less ice there is, the more earth receives. And so, the coming and going of ice is a big piece of the global climate system. Secondly, ice is a sensitive and unambiguous indicator of climate change. On Earth, ice is very close to its melting point. And a few degrees warmer, and you get a substantial reduction in Earth’s ice. And likewise, if we were to have it be a few degrees cooler, we would see an expansion of Earth’s ice. But changes in temperature result in very visible changes in the distribution of ice on Earth.

And so ice, as a sensitive indicator, also is a good vehicle to tell the story of climate change. And ice is also neutral as an indicator. This is the only reading from the book I’ll do for you, but in it, I say that, “Ice asks no questions; it presents no arguments, reads no newspapers, listens to no debates. It’s not burdened by ideology, and it carries no political baggage as it crosses the threshold from solid to liquid. It just melts.” And that’s why it is to be an indicator, and it leads to big changes in the distribution of ice on Earth with very small changes in Earth’s temperature. The third reason that I have chosen to tell this story through ice is that, the consequences of Earth losing its ice are very big. The first ice to go will be the glaciers that sit on top of mountaintops in tropical and mid-latitude regions. And they are melting back very, very fast. The ice on Kilimanjaro, which is very nearly on the equator, will likely be gone in another decade. The ice in the Andes — the equatorial Andes and temperate Andes — is shrinking fast.

Glacier National Park will probably not have its name sake, glaciers, in another two decades. The importance of this meltback is that, the water that comes from melting mountain glaciers provides the agricultural water and the domestic water — drinking and sanitation and the like — for about a third of Earth’s population, is a tremendous resource that, once it’s gone — if you think there are water problems, water shortages, and certainly you in California know about water shortages — you will see that same story all over the globe. In the parts of Asia where the water supply comes from the high Himalayas. In the Andes where much of Peru, Chile, Bolivia, their fruit industry, their flower industry. Much of that will be greatly distressed and imperiled once the mountain ice is gone. The other big consequence of melting ice is that, eventually, it leads to higher sea levels. When you turn ice into water, the water runs downhill.

It eventually comes into the ocean, which alone, will raise sea level. But, as the oceans themselves are warming up, as the climate changes, they also thermally expand. And that is an additional source of sea level rise coming from the warming simply through the physics of expansion of water. And so, those are the reasons that I’ve chosen ice as the vehicle for this book. Now, I try and develop the story of ice on Earth as a panorama through time starting roughly at the peak of the last Ice Age, about 20,000 years ago. At that time, ice covered all of Canada and North America, from the Canadian border down to about the Missouri River in the west, and the Ohio River in the east. And in fact, those two rivers were actually the result of carrying away all of the melt water from the last Ice Age, and they define the southern limit of the ice.

In Europe, ice came as far south as about the midlands in the United Kingdom, and through Central Europe and the like, and had mountain glaciers in the Alps. And, as a result, there was an immense amount of ice. But ice and water are what I call, “Playmates on a Seesaw.” And, when you have a lot of H2O tied up in ice, you have much less of it tied up as water. And so, when you have ice on the continents starting an Ice Age, you also have much lower sea levels. And, in fact, the ocean level at the height of the last Ice Age, was about four hundred feet lower than it is today. And it exposed large swaths of the continental shelves — which conveniently provided pathways for humans to migrate from place to place and from continent to continent. The Bering Land Bridge was certainly an important one. The English Channel was dry, and so, the communication between the United Kingdom — not yet the United Kingdom but that terrain and continent of Europe — was just a walk.

And throughout Southeast Asia there was a lot of dry land that facilitated human migrations. And so, the high ice volume, low water level was a characteristic of the peak of the last Ice Age. Now, how about the people? At that time, they weren’t many. The total population of the globe, about 20,000 years ago, was perhaps on the order of one million people. One million people. Pick out your favorite city with one million population, but imagine that spread over the entire globe. That’s the population density of the peak of the last Ice Age. Well, now, we have a different situation. We’ve come out of the last Ice Age, and we have seen ice reduced on the globe. The main places for ice today are on the tops of the high mountains in the tropics and mid-latitudes, and in the big icecaps in Antarctica and Greenland, and then, in the frozen sea ice of the Arctic Ocean. The ice on the Arctic Ocean is not very thick, it’s just sea ice that has frozen.

But, those are the main places where we have ice. So we have reduced ice, but we have a lot more people. From the one million people at the end of the last Ice Age to the year about 1800, the growth of population went from one million to about one billion. 1800 was the year when Earth first reached the threshold of a billion population. So that took, let’s say, almost 20,000 years. But the next billion, between 1800 — the next billion came in 1930 — 130 years later. And the next billion after that came in 1955. And the next billion after that came in 1974, when we reached 4 billion people. And today, we’re approaching 7 billion. And we’ll reach 8 billion by 2025, or so. And 9 billion perhaps at mid-century, depending on which way the demography goes. That’s a lot of people.

If you were to take Earth’s population today — close to 7 billion people — and try and grasp how many people that really is. If someone were born every second, and no one ever died, it would take more than 200 years to produce 7 billion people. So it’s an astounding rate of growth that we’ve experienced in just the last couple centuries. Not only, of course, do we have a lot of people, but they’re a lot more clever than were the cave people and the people living on the fringes of the ice during the last Ice Age. The people today have learned to use energy. And I know that, in the other talk by Steve Chu, the subject of energy usage, the subject of carbon-based energy, and the need to make the transition to non-carbon-based energy, was under heated discussion when I left. So we have, not only a lot of people, but they all use a lot more energy, and the energy let’s them make a big impact on the Earth as a whole. The landscape of the Earth that we have admired for a long time — such as Yosemite Valley here in California, the Great Lakes in the Midwest, the Finger Lakes in New York, and other characteristics around the globe, was all carved by ice during the last Ice Age.

But today, humans are becoming a big rival for Earth-moving. Currently, humans move more earth than rivers do. And we have a process of mining going on in the east today called “mountaintop removal,” where they simply blast the tops off of almost five hundred peaks now, or crests, in the Appalachians, and dump the debris into the surrounding valleys to be able to mine coal that’s a few meters under the surface. So humans have become rivals of nature in the ability to move earth. We have interfered with the hydrological system in dramatic ways. We have dammed every major river in the USA. There’s not an uncontrolled river that flows to the sea. No longer. And we have, not only added all kinds of chemicals to the environment, but they are eventually making their way to the sea as well. Currently, the use of agricultural fertilizers and the chemicals that accumulate on the impervious surfaces of our cities and are washed into the sewer systems by big storms — those make their way to the sea, and are today causing dead zones in the sea where the major rivers empty into the ocean.

The coast off of Louisiana, where the Mississippi enters the sea, has very substantial and extensive dead zones where, effectively, nothing is living. We’ve had big impact on our atmosphere. We have, you know, created smog that drapes our cities and acid rain that falls on our lakes and forests, killing both the trees and the fish in the lakes. And, we have used the synthetic chemicals, the chlorofluorocarbons — put them to great use, but later discovered that they were destroying ozone over Antarctica at a creation of the Antarctic ozone holes directly linked to our use of synthetic chemicals. And among other things that we’ve been putting into the atmosphere are the greenhouse gases. Carbon dioxide is a direct product of burning the carbon-based fuels: coal, petroleum, natural gas. And the carbon dioxide, for the most part, is going into the atmosphere.

Some of it gets dissolved in the oceans, but the oceans can’t take it up fast enough. And so, the concentrations of carbon dioxide in the atmosphere have been growing. We have known, from studies of ice cores, what the concentration range of carbon dioxide has been in the past. Through ice ages and periods between ice ages, carbon dioxide in the atmosphere has oscillated between about 200 and 300 parts per million. Today, the concentration in the atmosphere is well out of that range of natural variability. We are at 390 parts per million and adding two or three parts per million to the atmosphere every year under our current industrial economy. And so, humans are embarked on a vast experiment — an inadvertent experiment with the chemistry of our atmosphere — and the nature of that chemical experiment is also one that is an experiment with our climate.

And, because the greenhouse gases trap heat trying to leave Earth, the atmosphere warms, the surface warms. And it is that warming that is having its impact on the ice of the world. And so, what is happening to the ice? As I mentioned earlier, mountain glaciers everywhere are retreating. And it’s likely that most mountain glaciers in the world will be gone before mid-century. We also see big changes in the sea ice of the Arctic Ocean. The Arctic Ocean, I mentioned earlier, is just frozen sea water. That’s the icecap on it. It’s on the order of oh, 15 feet thick in many places, a little thicker sometimes in other places. But in the summertime, there’s a little bit of a breakup of the sea ice in the Antarctic, until the last few decades when there’s far more than little bit. The area of sea ice in the Arctic Ocean in the summer has been shrinking dramatically over the last few decades, until today, about only sixty percent of the area of summertime sea ice that formerly existed is present today, and its thickness has been reduced by about half.

The net result of that is that, the Arctic Ocean is much more open, and the sunshine that might have been reflected away by the white sea ice is now being absorbed by the dark sea water and warming the Arctic Ocean. What that does is, it prevents the freezing in the fall. It pushes it back a few months later into the fall. And it also leads to earlier breakup. So we’re on a pathway, I think, to see an ice-free Arctic Ocean in the summertime in just a few decades. And that will be a whole new regime change in the Arctic. There will be commercial interests that will move in very quickly, searching for resources. There will be fishery ships coming in and scooping up the Arctic fisheries resource. There will be trade routes open up. The fabled “Northwest Passage” and the “Northeast Passage” will become reality, and lead to much more sea traffic in the Arctic Ocean. And so, big changes just due to the loss of sea ice in the Arctic Ocean. Then, of course, comes the rise of sea level. Sea level rice is not something of the future; it’s already happening. Sea level has risen about eight inches in the 20th century.

And the projections of the IPCC — and I’ll come back to how conservative they are in a minute. The IPCC said that you can expect another two feet of sea level rise in the 21st century. Now, that is far and away a lower bound in my mind. Because we’re learning a lot of things about how rapidly ice is leaving Greenland and Antarctica, and popping into the ocean. The IPCC calculation of what we could expect in sea level was basically a melting calculation: How fast Greenland would melt, how fast Antarctica would melt, and that water would eventually make its way to the sea. But you don’t need to wait for ice to melt to raise sea level. If you drop an ice cube into a beverage glass, you’ll see that the level in the beverage glass rises right away. And we’re now witnessing wholesale loss of ice from both Greenland and west Antarctica.

Greenland has the equivalent of about 20 feet of sea level rise with its ice and West Antarctica the same. East Antarctica is a much bigger pile of ice, and it stands much higher. And it’s going to take a lot more to destabilize that. But Greenland and West Antarctica are already losing their ice at faster rates than the IPCC had predicted. Now, the IPCC understood why its projections were on the low side. Because, already, the rapid acceleration of ice off of Greenland was visible and the same in West Antarctica. And the reason being that, there is a lot of summertime melting of the top of the ice sheet, and the water was finding its way down through fishers to the base of the ice sheet and lubricating the base of the ice sheet. And it was slipping off much faster than simply melting from the top. In the Antarctic, some of the big ice shelves that are simply glacial ice that spilled off the continents onto the sea — they too are becoming unstable, because the sea water is warming and eroding them from below and thinning them and breaking them up. And so, my guess is that, we’re more likely to see something on the order of three to six feet of sea level change in the 21st century.

Now, what would that mean? What would three feet of sea level change mean? Well, it means that you would lose about the southern 20 percent of Florida. It would be reclaimed by the sea. All of the Florida Keys would be gone. Much of the gentle, Atlantic seacoast of the Carolinas and Georgia would see big incursions of the sea. But the human tragedy is big. If you look at how many people live within three feet of sea level the world over, you’ll discover that the number’s about 100 million. And we experienced the social problems of dealing with dislocated people, with the people in New Orleans, following Hurricane Katrina. We had about a 150,000 people that were climate refugees. The number of people affected by three-foot rise in sea level is about 100 million people worldwide.

And that’s a social challenge and international challenge of the first order. And it gives urgency to all of the things that Secretary Chu is talking about in the other auditorium just a few moments ago. Some people say that we should not let the concentration of greenhouse gases reach beyond 450 parts per million — that really bad things start to happen then. Currently, we are at 390, and increasing at around three parts per million every year. Well, you can do the arithmetic. I know that people at Google are good at doing arithmetic. There’s sixty parts per million to work with, and if we’re adding three parts every year — that gives us about two decades to stabilize our emissions of greenhouse gases into the atmosphere. And, that may sound like a long time, but two decades to totally reinvent the energy usage — energy supply — around the world, is a big challenge. Now, I was listening to Secretary Chu, and he was asked the question, “Well, are you optimistic?” And in some ways, I am optimistic. Because I know that, once you get people’s attention in serious ways, that they can respond very impressively.

I’m old enough to remember World War II when U.S. was suddenly hit over the head with a two by four. That was our entry into World War II. And, all the best at industry was ended and converted to a wartime industry. No more passenger automobiles. No more refrigerators. No more appliances. Every bit of industry was turning to build airplanes, tanks, vehicles, artillery. And, in just one year, the transformation was so dramatic, that one aircraft factory near my hometown in Michigan — one aircraft factory — was making more airplanes than all of Japan. And that was a transformation of dramatic proportions. But it took something to get our attention. And I think that we need to pay attention now. That’s one of the reasons that I wrote the book. And it’s one of the reasons that I try and talk in various venues around the country — even around the world for that matter.

To make people very aware that we don’t have a lot of time to dillydally, and that there’s a real sense of urgency in making a transformation to non-carbon-based energy. If we do that, we’ll still be able to retain our ice. If we don’t do that, then you’re going to get what I have as the title of my book, a World Without Ice. With that, I’m going to stop talking. And I’d love to have some discussion with you, and to hear your thoughts and your questions. And let’s have a good chat. Thank you very much. >> [Clapping] Dr. Henry Pollack: What’s the custom here at Google? Does anyone just stand up and go to the mic, or whatever? All right. We have a volunteer. Q So, I think one difficulty that we face on this issue is basically communicating sort of, What exactly the sort of global threat that we’re envisioning if we get to 450 parts per million to the general population? Because it seems kind of abstract.

Dr. Henry Pollack: Well, it does. And the reason that ice may not be a perfect medium is that, the ice is a long way away from where the people are, but the sea level change affects the entire globe. And so, the task is to have people be aware that, what seems to be a remote issue, in fact, is one that has very direct consequences. Q And, just to follow up, so it sounds like, based on what you’re saying that, kind of, the direction that we’re headed is maybe losing lots of ice whether we get to 450 or not. Or maybe that’s only if we get to 450, then that’s going to start happening. Dr. Henry Pollack: No, it’s already happening. We don’t want it to go beyond that threshold. Some actually think 350 is the proper threshold. We’re already past that. They want to return as quickly as possible. Bill McKibben is one who advocates that. But, I think that the answer — the real question you’re asking — is, we have to translate this into issues that are closer to home that people do understand. And, in that context, I think that the global financial crisis is a stroke of luck.

Sorry that, you know, for all the people who are out of work, that’s no stroke of luck at all. But it is kind of the lack in the head that I speak of where people say, “Gee, everything we’ve been doing suddenly doesn’t seem like we really knew what we were doing. So, maybe we can take bold steps now.” And Al Gore said something like, you know, “Our dependence on foreign oil and the security issues associated with that, our status as the world’s largest debtor nation, our financial instability around the world, and climate change are not four separate problems. They’re all four facets of the same problem — a misguided, national energy policy.” So I admire the way that Steve Chu and his colleagues in Washington are focusing on energy. If we get our energy policy right, that’s something everyone understands locally. They don’t have to think about polar ice to get the message.

So having that now as a vehicle to get people’s awareness and their creativity thinking — going — I think is a good step. Q Hi. Dr. Henry Pollack: Hi. Q Thank you so much for coming. Dr. Henry Pollack: Thank you. Q So, if you see that a lot of these things are already happening, and you could see the change, my first question is, How do you still sleep at night if you know that this was all coming? Dr. Henry Pollack: Well, it’s a good question, because I’m as concerned as any. And I don’t lose sleep over it, but I do think about it and try and think of, “What can I do differently to reach more people to develop an awareness?” And so, while — as I say, I’m not losing sleep, but it has energized me during the day to explore as many avenues as possible. And one of them, I should say, is that, people say, “Well, what can I do individually to help mitigate climate change?” And, of course, you heard all of it. You know, we want to have our houses more energy efficient.

We want to have our transportation more energy efficient. We want to change lightbulbs. We want to drive less. We want to choose where we live so we don’t have to commute so much. And all of those are important, personal decisions. I’ve even become aware of — even rethinking your eating habits is something that can have a big impact. Because, of course, there’s so many of us, and choices among foods have very real, energy implications. But, I still think that the problem is so big that it won’t come from volunteers or more individual choice. We need both state and national policies and international policies that become from our elected representatives, and so your vote is very important. If the people that go to Congress that represent you aren’t representing you on this issue, you should let them know that. And let them know, if there’s an election in 18 months, or whatever, and if they don’t establish a track record, you know, we’re going to work hard to move you out.

So votes are important, and communicating your impatience with your elected representatives is important. They do understand that they have to get reelected. And, if you cast it just that starkly, that plays a big role. We’re not going to do it individually; we’re going to do it through national and international policy and leverage. Thank you. Q Hi. I was wondering if you could — I know this is a complex subject — but try and explain the cooling and warming model a little bit. Because — to me, who is sort of untrained in this — ice and carbon seem like two different things. And if we factor out people, you know, you talked about reflectivity, and that completely makes sense. I can see that. But, if I apply that to the past Ice Age, it would seem like, “Oh, we’d never warm up again. Because as the ice got thicker and thicker, we’d get more and more reflective, and then there’d be nothing to tip the balance back.” And so, there must be something. And so, I was wondering if you can kind of unify that model? Dr.

Henry Pollack: Yeah, well, it’s not my unification. It has been, of course, studied intensively. And, in fact, ice ages do end. And they’re followed by rapid warming. But part of the end of ice ages has to do with orbital factors in the Earth and its orbit about the sun. And that, the tilt of the Earth’s axis — which is today about 23 and a half degrees from the plane of our orbit about the sun — that actually oscillates between 21 and 24 degrees. And the shape of the ellipse about the sun oscillates with a period about 100,000 years. And the procession of the equinoxes, which determines which hemisphere is getting more sunshine in June or December — that has a period in the low 20,000 years. And those factors are the big pacemakers of the ice age. But, what we’ve noticed is that — throughout the ice ages — temperature and carbon dioxide have marched together. Now, the lesson of that is that, the two are strongly coupled. That the temperature and the carbon cycle are tied together. And whenever either one gets out in the lead, it pulls the other along. So, if the temperature were to warm, it would pull the carbon dioxide up. If the carbon dioxide is added, quite independently of temperature, it would pull the temperature up.

In the current world, we are pulling carbon dioxide way out ahead of temperature, and the temperature is starting to catch up. And so, yes, there are the long period, orbital factors that play a role, but right now, we are pulling carbon out of the Earth, and sending it back to the atmosphere at a pace that it hasn’t seen for over a million years — probably many million years. Q So I can imagine how we can adapt to rising sea levels and missing ice. I’m more concerned about ocean acidification. I wonder if you have any insider words to add about how dramatically the ecology of the oceans will shift as the pH drops? Dr. Henry Pollack: Well, there’s quite a well-established, observational data about the slow decline in the pH. And the oceans are still not acidic in the technical sense, but they’re approaching — they’re becoming less alkaline and approaching acidity. And that, of course, does affect any of the organisms that use calcification as the way of building their shells or their reefs or whatever.

We’re just beginning to see studies that show that coral reefs are having trouble. Some of the bivalves on the ocean floor — their shells are thinning. And so, it’s at a stage now where you’re getting all the early warning signs. But, just as we need to stabilize our emissions into the atmosphere — after all, that is what is driving the decrease in pH in the oceans is that, the oceans are asking to absorb more and more of the carbon dioxide from the atmosphere, and they do that, but it’s changing the pH. Where it’s going to take us is not so clear to me. I’m not a biologist, and I don’t have that insight. But, it’s a very real problem, because the marine environment, of course, is a huge source of human nourishment, and to see that be impacted in this way is ominous.

Now, I might add that there are schemes afoot to block sunshine. It’s called geo-engineering or climate-engineering, by putting artificial pollution into the atmosphere to reflect sunshine away or to spray water vapor into the atmosphere to promote cloud formation. All of that is to, kind of, mechanically interfere with sunshine reaching the Earth, but that doesn’t do anything for the problem you cited. If we’re still pumping out carbon dioxide and trying to adjust climate by reducing sunshine, the carbon dioxide is still going to go into the ocean and lead to a drop in pH. So I think that the geo-engineering or climate-engineering solutions are shortsighted if they focus only on blocking sunshine. Q Apologies if you covered this earlier in your talk, but methane is one of the other large contributors to effects in the atmosphere. And we have, you know, billion of tons of biomass in the Arctic that’s thawing out and letting methane out. It seems to me that could have a pretty disastrous impact on the behavior of the atmosphere and I was wondering. Dr.

Henry Pollack: The comment that, as the regions around the Arctic are thawing out, the permafrost degrading. And that, there’s a lot of methane locked in the permafrost that’s making its way to the atmosphere. And that’s all true. And there is also methane stored in ice just below the ocean floor, which has a huge amount of methane that, if it were destabilized and went into the atmosphere that, it too, would add to the greenhouse gas burden of the atmosphere. About the melting of the permafrost — once again, kind of the first stage of measurements in the permafrost lakes that are developing — show — yes, indeed — there is a methane flux. And how fast that will penetrate — the melting will penetrate — and release more, is the big question. Most calculations of the diffusion of heat downward to melt the permafrost and release the methane, shows that it’s not a fast problem. It’s one that would progress slowly and have a time scale that would be in the centuries, rather than an immediate belching out of large amounts of methane. So while it’s nothing to trivialize, it’s not something that’s going to overwhelm us with a very fast and furious feedback into the greenhouse.

Q I was, I guess, looking more at the Arctic climate in Siberia as opposed to the one in, say, northern Canada, because the biospheres there were tremendously different. Dr. Henry Pollack: Well, the area that’s been studied — at least that I’m familiar with is, in fact, the Siberian permafrost. That’s where these early measurements that I was describing first were made — I’m sure the Canadians are active too. But as you pointed out, maybe it’s quite a different biosphere. So I can’t offer a lot of insight into that, other than to say that, I think that the physics of the destabilization is fairly slow. Yes? Q Hi. I think it’s great that there is more consciousness, you know, around our problems and people are changing habits and there is progress being made, but I still worry very much about the rate of that kind of progress when you talk about hundreds of millions of billions of people being added to the Earth. When you talk about we’re only sixty million parts away from a really nasty threshold and we’re rising quickly. You talked about how quickly the — in your point on being optimistic — you saw what happened in your town with the conversion to military industrial capability.

Where’s the Pearl Harbor, though, that’s going to help us out this time? Dr. Henry Pollack: Where is the Pearl Harbor? Where is the two by four that gives us the whack? I can envision two by fours. I can envision, for instance, a large dislodgement of ice from Greenland that would raise sea level, you know, maybe three or four inches at one time. That could happen, and three or four inches is a lot. When you think of what it means and increasing the strength of any storm that strikes the seashore. The storm surges are bigger; the tides are bigger. Everything about it suddenly is augmented by this half foot of sea level rise. That maybe would get attention. It’s hard to know what kind of an earthquake that it would take to say, “Wow, this is, you know, we really have to do something about it.” And part of that, I think, has to do with — people don’t consider themselves strong in the face of nature — that they are wowed by earthquakes, that they’ve seen their actions before, and that they say, “Woe is me. You know, hurricane or tsunami or an earthquake. You know? Who am I in the face of powers of nature?” But what they don’t realize is that, collectively, all — almost seven billion — of us are now the most powerful, geological force on the planet.

And it’s that awareness that has to shift. And that’s a tough one, because it’s a cognitive problem. It’s a sociological problem. It’s not quite the same as a surprise attack. >> So I wanted to thank you for coming to Google today. And, for those of you who got books, he’ll be signing books over there after this. So, thank you for coming. >> [clapping] Dr. Henry Pollack: Thank you. >> It’s wonderful..