2008 Climate Change Lecture

good evening it's wonderful to see such a full house is everybody comfortable now okay well I am absolutely delighted to welcome you to this which is the the first lecture in a new series for the school of the environment of distinguished lecturers and we are very honored to have a special lecture with us here tonight before I move on though I do want to thank a couple of people and first of all I want to express our appreciation to the Sierra Club of South particularly to South Carolina chapter and their president John Remsburg whom I've lost track of right now though there you are John who's been really instrumental in enabling this evening to happen and the other person or people I want to thank is my staff in the school of the environment who have been really essential in putting this together so again welcome to this lecture I am dr. Madeleine Fletcher the director of the school of the environment and I'm very happy to be able to introduce to you tonight our speaker dr. James Hansen and he is the director of the NASA Goddard Institute for Space Studies he also has an adjunct appointment at Columbia University and I just want to mention briefly I promised to do this briefly a few of the honors that he has received he is truly befitting of our first distinguished lecturer here he won the 2000 or he was awarded to 2001 Roger Revelle award for a merit for the American Geophysical Union for outstanding contributions towards an understanding of the Earth's atmosphere he's won two national president but NASA presidential rank Awards and an exceptional service medal he was selected for the National Academy of Science in 1996 in 2001 he got the hinds environmental award in 2007 the Dan David prize for achievements having an outstanding scientific technological and cultural or social impact in our world and the 2008 Commonwealth award of distinguished service for his outstanding achievements and science dr. Hansen has made an extraordinary contribution to our understanding of the planet and the various factors that have influence on climate change and more important he's advanced our understanding of how we can address these potentially profound changes on our planet so it's a great privilege for me to be able to introduce to you dr. Jim Hansen thanks very much and thanks very much for coming here and spending your time and I'm especially glad to see so many young people because it's this subject is particularly important for you and I'm especially concerned about the intergenerational issues of equity and justice which I'll emphasize oops this one now what today - let me see if I get rid of that escape okay thank you now I tried these arrows okay that's better all right I'll stay away from that one yeah this there is unfortunately a large gap between what is understood about global warming by the relevant scientific community and what is known about global warming by the people who need to know and that's the public and the policymakers and it's hard for you to believe you know if you stick your head out the window the weather seems great we don't see much unusual happening but the truth is we have reached a point a crisis point and the reason one reason that it's hard to notice it is first of all there are large weather fluctuations of 10 degrees or 20 degrees from one day to another which causes you not to notice slow changes that are smaller than that and the climate system has inertia which is especially due to the ocean which is 4 kilometres deep so it takes it a long time to respond to a change a change in a forcing which I'll talk about but so as a result the changes that humans have made to the atmospheric composition only a fraction of the ultimate response has has occurred yet there's more that's in the pipeline even if we don't make any more changes and also that climate system has tipping points you can reach a point where the changes don't occur very rapidly but you reach a certain point and then suddenly things happen much faster because of positive amplifying feedbacks in the system and that makes a danger of losing control of the system and the bad news is that we have realized in just the last couple of years that the dangerous level of atmospheric greenhouse gases is much lower than what we thought the good news is that that means we're gonna have to make some changes which actually have a number of other benefits including for human health and agricultural productivity and other things which I'll mention this that's my newest grandson and I gave a talk last week in Virginia Tech and they rearranged the time for my talk so I could get home in time for Jake's first birthday but there's another reason for that so I'd admit that's why I made this chart to show them but there's another reason to show him one of my grandchildren and that is that I you know I had talked about this subject in the 1980s testified to Congress and it got a lot of publicity then but I decided that was not what I wanted to do and so I got out of that business completely and after 1989 I testified in 1988 1989 and I I'm not I'm not a public speaker and I don't enjoy it and I don't I prefer to do science and there are there are some scientists who really like it so I decided to leave it to them and for 15 years I wasn't involved I didn't go on television or anything 15 years but then in the current administration in 2001 I had had the opportunity to speak to the vice president's Energy and Climate group six cabinet members and actually I got to speak to them twice and of course their policies were not were were not addressed to really reduce any emissions they were so but they said they were open to more information and and the president declined to join the Kyoto Protocol but they said they were open to more information and I did get the opportunity then in 2003 to go back to the White House and and present what I thought was much stronger evidence for what we that were really reaching an emergency situation and still didn't get make any progress in affecting policy but I didn't so in 2004 I or over a few months period decided thought about this and decided I didn't want my grandchildren to say oppa understood what was happening but he never made it clear so I decided to start writing things which could be understood by a wider audience and and giving some talks now and so I've done there now for years I wouldn't say that it's affected any policy yet but anyway I have been giving a few talks now one of the reasons that it's hard for people to notice anything is that the weather fluctuations are larger than the global warming and so if you look at even if you average the weather over a month that temperature anomaly relative to a period of climatology can be warmer than normal normal or colder than the climatology some places are red in yellow which is warmer and some places are blue which is cooler so there are more places warmer than normal but it can go either way but if you average those anomalies over the first seven years of the century you see that actually the anomalies are above normal almost every place and they're larger at high latitudes these are anomalies in degrees Celsius so you multiply times approximately two in order to make degrees Fahrenheit but warmer larger at high latitudes and low latitudes because there are amplifying feedbacks at high latitudes as ice and snow melts it exposes a darker surface which absorbs more sunlight and that magnifies the effect and it's larger over land and over ocean because the ocean has this inertia so it's only partially responded to the forcing and larger in the Northern Hemisphere than southern hemisphere because the southern hemisphere has more ocean and it mixes deeply around Antarctica so the warming so far is eight tenths of a degree Celsius in the last century which is about one and a half degrees Fahrenheit and it fluctuated for a while both be for various reasons of competing forcings and natural variability but the last 30 years it's been a fairly steady warming trend with most of the three-quarters of the warming in the last 30 years this has had two other grandchildren and I when I talked to the vice president's group the cabinet members I tried to explain what a climate foreseen is a climate forcing is a perturbation of the planets energy balance so for example if the Sun became one percent brighter that would be a forcing of about two watts per meter squared because the earth absorbs 238 watts per meter squared of energy from the Sun and so and the amount of greenhouse gases co2 and methane that we've added to the atmosphere those gases are transparent to sunlight so they don't affect that but they're opaque they're they absorb infrared radiation or the heat radiation that the earth mints so they make the atmosphere more opaque in the infrared and that means the radiation to space will arise from a higher altitude and as the temperature falls off with altitude so that means the emission to space is reduced if you add greenhouse gases and of course the planet then is out of balance absorbing more energy from the Sun than it is emitting and that causes the earth to warm up until it gets to a point that it's back in balance again well the greenhouse gases that we've added are forcing of about two watts so sophie was explaining to connor what two watts of energy is and that's that was three years ago this isn't this is recently and in Connors no longer so fantasy was now never this you know you can ask the question a well-educated person can ask the question why should it be concerned about this there have been much larger climate changes in the Earth's history there have been huge changes and it's arrogant to think that we can control the climate or that we know enough to say that today's climate is the best one for the planet this was a statement made on National Public Radio by my boss's boss's boss the nest NASA Administrator and so it is a question a reasonable question that a well-educated person can ask and it's true that it the climate has had much LARC very large changes in the Earth's history those changes actually tell us a lot that's relevant our understanding is based especially on the Earth's history we learn more from that than we do from climate models for example because we never know for sure if we've got all the physics in the models right also just looking at what's happening today with the climate forcings that we're putting on the system is also very useful but to start with the Earth's history the this is the temperature at near the South Pole which fluctuates this is over the last 400,000 years and we get this the temperature by drilling a core in the ice sheet the Antarctic ice sheet is formed by snowfall piling up year after year and so you can sample the snow that was laid down at different dates and from the isotopic composition of the snow you can tell what the temperature was when the snow flake formed and we've been living in this Holocene this warm period for about 10,000 years 20,000 years ago we were in the middle of the last ice age when there was an ice sheet that covered Canada and it covered in New York and Minneapolis and Seattle but the Earth's climate fluctuates between warm periods and then gradually goes into these ice ages and these fluctuations are associated with small changes in the Earth's orbit the Earth's orbit is not perfectly circular it's elliptical but the ellipticity changes when a timescale of a hundred thousand years and the date at which the earth is closest to the Sun in that elliptical orbit changes with about a twenty thousand year period isset E and the tilt of the Earth's spin axis it's the Earth's spin axis is tilted by 23 and a half degrees to the plane of the Earth's orbit and that's what gives us the seasons but that tilt fluctuates by plus or minus one degree and that's those small changes in the distribution of sunlight on the planet change the climate mainly by for example as the tilt becomes bigger then there's more sunlight at the poles and that will tend to melt the high latitude ice sheets and as the ice sheets melt and you get this positive feedback or darker surface and the planet gets a little bit warmer when it gets a little bit warmer co2 will come out of the ocean just like it comes out of your Pepsi if it gets warm so that introduces more greenhouse gases into the so and this is what we see when the planet is is warm then you've got more co2 in the atmosphere and and more methane and this is a chamber temperature down here well we can use this we can compare this present interglacial period the Holocene with the last ice age to estimate how sensitive the climate system is to climate forcing which as I say it's a perturbation of the planets energy balance because the things that kept the planet colder during the ice age have to be either energy coming in but we know that on that shorter time scale the sun's brightness doesn't change significantly or something in the atmosphere or something on the surface well we know the changes in the atmosphere because in this same ice core there we can sample the bubbles of air that existed at each point in time over the last four hundred thousand years so we can tell how much well I showed you already the graph for how co2 changed those greenhouse gases caused a forcing of about three watts per meter squared but the increased the changes on the Earth's surface mainly the larger areas of ice caused a forcing of about three and a half watts per meter squared so that implies the sensitivity of 3/4 of a degree for each watt of forcing that's equivalent to three degrees Celsius for double carbon dioxide because doubled carbon dioxide is four watts of forcing and we can check that sensitivity for that entire four hundred thousand years because we have not only a record of how the greenhouse gases changed over that period but we also have a record of sea level and sea level changes a lot sea level twenty thousand years ago was a hundred and ten meters lower than it is now but that water which is not in the ocean is in the ice sheets on the land and so we that's how we know how big the ice sheets were and so we can calculate the forcing due to both the ice sheets and the greenhouse gas and if we add those two up and multiply by three quarters of a degree we get a calculated temperature which agrees very well with the observed temperature so it tells us how sensitive the climate is and now we just recently got an 800,000 year record from a longer ice core and in a degrees very well on that time period also and now the thing is that humans I've expanded the timescale at the end just to show the modern observations and methane is increasing far off the chart and co2 is increasing far outside the range that has existed for millions of years and of course those increases are due to fossil fuel use primarily although there are also other sources of methane and one thing that the contrarians point out and become very confused about is the fact that if you look very carefully at these variations of the greenhouse gases and the temperature you see that the the temperature changed first it slightly changes it begins to change a bit and then the greenhouse gases increase and then the temperature increases some more and the greenhouse gases increase some more so it's a feedback on these time and that's exactly what we expect because the instigation for these swings is changes in the Earth's orbit and the way they work is as I explained so of course the temperature changes first but then the greenhouse gas is half of the reason for the temperature change the other half of the reason is the change in the surface albedo and the instigating forcing which is only a couple tenths of a watt per meter squared is a very small fraction of the direct of the ultimate cause of the temperature changes and that shouldn't be so hard for the contrarians to understand but nevertheless in order to show you an example which is also very instructive we can look at timescales on which the greenhouse gases do change first and the temperature responds to that change it all we have to do is look at longer timescales so what I've done here is this is the temperature change over the last 65 million years which is called the Cenozoic era it follows just after the extinction of the dinosaurs and the last three million years are blown up here to show you what it looks like on a higher resolution and then the last four hundred thousand years are blown up here and that's the familiar ice age cycle and you can see that those ice ages were occurring at all times but there are small although those are huge changes they're small in comparison to the total change that occurs from the present back to say 50 million years ago in fact between 65 million years ago and 35 million years ago there was no ice sheets on the planet the planet was too warm to have ice but that now the reason that co2 that the temperature changes on these long timescales we know we know you know that the mechanisms have to be either the energy coming in or some changes in the atmosphere or some changes at the surface but the energy coming in the Sun is a well-behaved main-sequence star and we know how they behave is slowly getting brighter with time it was four tenths of a percent dimmer 65 million years ago and that because the earth absorbs 238 watts that means the forcing of about one watt per meter squared the Sun the Sun slowly getting brighter by one watt and the surface that continents were located differently than they are now but they were close to their present latitudes and so the surface changed due to surface changes is also all but co2 50 million years ago was about a thousand parts per million that is a forcing to change from that to the amount of co2 during the ice ages is a forcing of more than 10 watts per meter squared so the dominant thing is the change in atmospheric carbon dioxide that we expect that our carbon dioxide will change on long timescales because the amount of co2 in the atmosphere depends upon the balance between sources of co2 and sinks of co2 the source of co2 is volcanic eruptions associated with continental drift as a continent moves in subducts beneath it ocean crust the carbonates in the ocean floor are metamorphosed into basalt and other rocks and there's carbon dioxide emitted in that process which comes out in volcanoes and seltzer springs such but the sink the primary sink is the weathering of rocks so the weathering will carry sediments down the rivers to the oceans and deposit on the ocean floor carbonates which is so that draws co2 out of the atmosphere of that process and also there's some deposition of organic material on the ocean floor which then can eventually form fossil fuels but so what was happening here 65 million years ago India was still located south of the Equator but it was moving north at a rapid rate of about 20 centimeters per year and as it was moving north it was moving through this so-called Tethys ocean which is now Indian Ocean but it that ocean had long been the Depot center for major rivers of the world so it had a very young carbonaceous a carbon rich ocean sediments ocean floor so as India's plowing through there subducting ocean floor it's spewing up co2 into the atmosphere and as co2 increased the temperature increased and then 50 million years ago India crashed into Asia and that began to push up the Himalaya Mountains in the Tibetan Plateau and so the source of co2 in this subduction is is reduced and the sink is increased because of the weathering of the Himalaya Mountains and so co2 gradually decreased and the temperature decreased until it hit it became cool enough that Antarctica began to have ice on it and it suddenly froze over with the positive feedbacks and so there are two interesting things about this the one is that if you look if you look at the rates of these processes the difference between the source and the sink is typically one ten thousandth of a part per million well over a million years that's a big change a hundred parts 100 ppm of co2 which is a big forcing but the human-made rate of change is 2 ppm per year so we're more than 10 thousand times more powerful than the natural rate of change so you don't it's true so the NASA administrators right yeah there were much bigger changes but you don't have to worry about those because we're totally dominant now those changes occur on a much slower time scale and the other thing that's interesting is well how much co2 was there at the time Antarctica began to freeze over well in a paper that will be published next week we show that it was about 450 parts per million so the assumption energy companies and governments around the world assume that we can burn all the fossil fuels if we do that we'll end up with 600 or 800 ppm of co2 in the atmosphere and we will have we will be headed toward a different planet avenge the eventual response of the system would be an ice-free planet with sea level 75 meters higher so we really can't do that and all in fact all the nations in the world are 170 of them agreed with this Framework Convention on Climate Change that said we should avoid dangerous human-made climate change but nobody defined what that meant what is dangerous I think that the two most important metrics are extermination of species because that is irreversible on any timescale that we can think about there have been large global warming several times in the Earth's history and when they did occur there was extinction of more than half the species on the planet and other species came into being over tens and hundreds of thousands of years but on any timescale we would leave a much more desolate planet for young people and unborn people if we caused the extinction of a large fraction of the species then Ice Sheet disintegration it takes tens of thousands of years for an ice sheet to build up by snowfall piling up so we don't want the ice sheets to disintegrate and there are also important regional climate changes and as I mentioned there are tipping points which we need to avoid you can temporarily exceed a given level that would be dangerous on the long run it provided you get back to a safe level if we suddenly had a thousand ppm of co2 and we had that for one day well that's not gonna cause ice sheets to disintegrate you can have it for a while but the question is how long when do you reach a point of no return and the process becomes dynamic and out of your control well here's a process that we've have probably pushed beyond the point of we've pushed to a point such that we're going to lose all the Arctic sea ice this is the Arctic sea ice from it fluctuates from year to year beginning in the late 1970s and then last year it but but it's been decreasing as the planet has become warmer and last year at decreased to almost down to half of what it was a few decades ago and because the planet is now out of balance by about half a watt per meter squared we're going to lose the rest of that Arctic sea ice in the summer that's almost certain within the next few decades but that is a reversible tipping point because if we would restore the planets energy balance or make it slightly negative then the planet would cool down and and the ice would grow back and it can go back in one year but we would have to reduce co2 to something like 300 350 parts per million if we wanted the planet to restore the sea ice the more important issue with regard to Ice Sheet stability we can examine by looking at the area on Greenland that has summer melting and that fluctuates with the weather but it the area in general has been increasing since we began to make satellite measurements in the late 1970s and last year the area with doubling with melting was about double what it was in the 1970s that melt water does not in general make it to the edge of the ice sheet it will find a low spot on the ice sheet and burrow a hole to the base of the ice sheet and it there serves as lubrication which increases the rate at which these giant icebergs are discharged to the ocean now some contrarians argued that well the ice sheets will actually get bigger with global warming because you get more snowfall because the atmosphere holds more water vapor and of course that's true but the common-sense conclusion would be as the planet gets warmer the ice gets smaller but and now we have a way to test that because we have this spectacular satellite which measures grace which measures the gravitational field with such a high precision that we can measure the mass of the Greenland ice sheet and the Antarctic ice sheet and we see that during the winter the it gains mass and then during the melting season it loses mass but overall it's losing mass at a rate of now almost 200 cubic kilometers per year and that rage if we don't we only have these measurements for a few years but we have other ways to estimate and it looks like if we go back about 15 years that it was close to mass balance and that rate rate of ice mass loss has been increasing over the last 15 years so if we want sea level to be stable it's clear that 385 ppm is too much and probably based on prior interglacial periods if we want the ice sheets to be similar in size to what they are we probably shouldn't have co2 much more than 300 ppm now another effect which is observed is the impact of global warming on the overturning circulation they're rising motions in the tropics and the subsidence in the sub tropics which causes the sub tropics to be dry that that circulation cell is expected to expand as the planet gets warmer and we observe empirically that there has been an expansion on the average by about 4 degrees of latitude and that's beginning to affect the southern United States and the Mediterranean region and Australia and parts of Africa and so for example Lake Mead and Lake Powell have are only about half fall and that's probably at least in part due to this general climate trend and a related effect is the increase in in fires that is occurring not only in the western US but in Canada and Siberia an important effect is the melting of glaciers which is occurring worldwide this is a picture taken in the Himalayas and then a more recent picture where that a glacier is now gone the glaciers in the Himalayas in the Rocky Mountains and the Andes Mountains provide fresh water in the summer and fall for hundreds of millions of people in the spring you get snowmelt which gives you a huge flush of fresh water but as the summer and fall go on there's no more snow but there's still the glaciers melting and providing fresh water but once those glaciers are come gone then there's these rivers will be running much drier and that's an important climate impact in fact these glaciers have now lost the black part of these bars show the loss mass loss of the glaciers as a function of altitude of the glaciers so already a significant fraction has been lost and it there's the danger that it could all be gone within 50 years if we stay on business as usual the coral reefs are another practical effect impact of well there are several stresses on coral reefs but two important ones are the acidification of the ocean as the atmosphere has more co2 it's and the ocean takes up the co2 the ocean becomes more acid and that is destructive for shell animal has shelled animals that are made carbonate or with carbonate skeletons because in effect it dissolves the shell and also the increasing temperature is a as a stress on coral reefs so all of these things tell us that we would be better off if we aimed for having co2 of less than 350 parts per million now if we want to keep a planet similar to that which has existed for the last 10,000 years unfortunately co2 is already 385 parts per million and the when we put a pulse of co2 into the atmosphere by burning fossil fuels part of it disappears quite rapidly after only 20 or 25 years about half of it is gone but then the rate of loss slows down and after a thousand years about one-fifth of it is still in the atmosphere the reason is that as the ocean takes up co2 it then begins to resist taking up anymore because the co2 in the ocean can come back out and until the co2 in the ocean has been taken up and has been deposited as sediments on the ocean floor it will continue to resist taking up the remaining fraction and that takes thousands of years for to form those sediments so you you simply cannot the bottom line is this we cannot burn all of the fossil fuels without producing a doubling or tripling or quadrupling of the amount of co2 in the atmosphere what we've burned so far is the purple part of oil gas and coal we've probably reached about used about half of the oil they're different there are different estimates for how much undiscovered oil there is but most experts think we're close to peak oil which means we've used about half of the oil if and it's you know you can't practically capture the co2 from because that's used in vehicles and you can't capture the stuff coming out of a tailpipe but you could decide so the target if we want to preserve a planet that looks like the one we have then we're going to have to target coal because that's the biggest source and we could decide will only use coal at power plants which capture the co2 none of which the presence of power plants do if we did that if we said we'll have more Tory Amon coal-fired power plants and will phase out the existing ones by 2030 then co2 would peak at a value of something between four hundred or four hundred and twenty-five ppm depending upon which estimate is more accurate for the reserves of oil and gas and then although that would still keep co2 above the 350 parts per million for a couple of centuries we could draw it down faster by means of improved forestry and agricultural practices or if we would capture co2 and the gas-fired power plants but especially the reforestation in areas that on marginal land that has been deforested but it's so it's technically feasible to get back to 350 but it would require a quick coal phase out over the next two decades and many people don't realize that coal is the main source of the excess co2 in the atmosphere as much as oil and gas put together and on the long run it's potentially even a larger fraction just because the reserves are the largest so that's really what has to be addressed now China has passed us in the past year they now emit more co2 than the United States but as far as who is responsible for the climate change it's actually mainly the United States because of the very long life of the atmospheric co2 so we're more than three times more responsible than any other single country so you know the energy departments and fossil fuel companies say that it's a god-given fact that we're going to use all the fossil fuels well I think that we should dispute that and I think especially young people should dispute it I think that it would be possible to phase out to coal co2 emissions and I think we need to do that but so we have I think a basic conflict between fossil fuel special interests and young people in nature and it's it's it looks like this is a very uneven fight because fossil fuel interests have money money talks in Washington and other capitals and as I say animals are not much help but but but you know we're gonna have to fossil fuels are not going to last forever anyhow so the world is gonna have to figure out an energy source other than fossil fuels so why not do it now instead of waiting instead of introducing something which we're certain is going to cause a huge problem for our children and grandchildren and in the unborn and all it does is is give us a little money for a short period time so we need a strategic approach but unfortunately we don't have leadership that looks at the long time scale and what has happened is the government's are now starting to talk about oh we know there's a problem we agree there's a problem and then they say we're doing this and that is really greenwash because what they're doing is are very marginal things which don't solve the problem they're the governments that are most green appear to be are planning to build more coal power plants so they simply don't get it I think that the two things that are essential are phasing out Koli missions and United Kingdom the United States and Germany are the most responsible on a per capita basis for the co2 in the atmosphere so we should be leading the effort but I also think that we need to have a price on carbon emissions because that and but in order if you put a tax on carbon emissions the only way the public will accept that is if you give all the money back to the public don't let the politicians decide how they're going to use the money or who so if you just gave it back on a per capita basis deposited in people's bank accounts on a monthly basis then those people who do who want to it would eventually be a lot of substantial amount of money and people would decide well I'm gonna save I'm gonna reduce my carbon emission so I reduce my tax and I'll make money those people who do better than average will make money and those people who have four SUVs or Hummers will lose money but that's fine so that would encourage innovation because those companies would want to make money so they would want to make products that use less fossil fuels and that would be the so I yeah I and and of course we should eliminate the fossil fuel subsidies and and that way the marketplace would choose the winner winners and it would we should change the profit motive of utilities right now utilities make more money if they sell you more energy their profits are proportional to the amount of energy they sell you we should change it so that they make more money if they help you conserve energy and and then the bottom line is that I want to emphasize is that I think this is really an intergenerational issue a question of equity and justice and our parents did not know about this so they had a defense but that defense is no longer viable nyeeehhh I even think there's a question of legal liability for those industries fossil fuel industries that have in effect hired contrarians to confuse the public about this story so that they can continue to make maximum profits and I think as I mentioned on that last point I think there's likely to be increasing public protests if I were a young person I think I would be protesting but this actually uh older people should be protesting but this there was this case in England where the United Kingdom where people climbed this smokestack and painted where they're painting Gordon Bennett on the tower where Gordon Brown is the prime minister of United Kingdom but they got arrested and they were charged with sixty five thousand dollars worth of damage and also threatened with prison terms but the jury declared they were innocent because they were protecting property of greater value which namely the planet and now unfortunately that doesn't set a precedent it doesn't set a legal precedent and I was last week there was this case in Wise County Virginia where young protesters were arrested and two of them were charged with 14 counts of crimes topped by obstruction of justice for blocking the entrance to the construction site for coal-fired power plant and they realized and their lawyer realized that they really had little chance of winning that case because of the unfavorable jury pool and the large number of counts against them they just didn't think it was likely that the jury would find them innocent on all charges it and it just seems that the justice system had it was the case of where the justice system is working hand in glove with the with the fossil fuel industry and so it's it's a continuing and but my I and and there was actually a story in The New York Times that said that I had had encouraged young people to to protest and and I in which is unlawful and I actually have not said that what I've said is that now is the time to try to influence the political process this year and I have had press conference with the group power vote and have tried to encourage young people to get active in the political process and then then after the elections you've got to hold the people elected accountable because they're just the the pressures the financial pressures from the fossil fuel industry and special interests just seems to be enormous and so somehow we've got to be able to hold politicians accountable but that reminds me I did meet some young people today one of them was and I'm at the end of my talk so I wanted and Fitzgerald to I give her a chance to make a comment about this [Applause] okay thank you so what what I I got thrown off my game so power vote is being run at 300 campuses across the nation we're running it here at USC it's being run at colleges at universities at high schools these are students who are standing up and saying I want a different future I want a future that is based on clean and just energy not a future that is based on fossil fuels dirty money and special interest and that is an incredibly powerful statement but we can't do that alone we need everyone in this room we need every person of every generation of every race of every Creed to stand up and say we want a different future and the best time to do that is this election this election we have a chance to hold our leaders accountable to making a difference and I don't care so much who gets elected as what they do after they're elected I want to see the folks who we elect on November 4th go to Washington go to the Statehouse go to our local governments and say what can we do about global warming what can we do about fossil fuel emissions and that is what signing this power vote card is all about the power vote pledge is the cornerstone of this campaign and I urge you to find a pen in your bag find your neighbor who has a pen and sign this pledge card because this is a way for you to get involved in this election and make a difference this is a way for you to exercise your political will so what are we gonna do with these pledge cards these pledge cards are gonna be delivered during powershift 2009 to Congressional to members of Congress and Senate they're going to be delivered by thousands of youth from across the nation right now we're looking at between 10 and 15 House 10 and 15,000 youth converging on Washington at the end of February to demonstrate to our leaders what we as a nation care about and we the youth are standing up and we the youth will continue to stand up but we need everyone to stand up along this our side so take the moment fill this out it does a world of good and then we will collect it at the doors on your way out or pass them to the aisles and on that note thank you so much for your time and now I ask dr. Hanson lots of hard questions thank you ranks and so we're open to questions and I'm told that it would be best if you had come to the microphone to ask your questions if you can get out the way fossil fuels staying in business is everybody in Alaska get to check for a well that's drilled in Alaska now the what that what has been proposed by my congressman Henry Brown and several other congressmen in this state is that the state of South Carolina can decide if they want offshore drilling and everyone in the state will get a check now my thought to you I come from Kentucky and in Appalachia our ancestors sold the rights to coal mining for almost nothing and now they can go in and they can mine your land and ruin your livelihood forever because those rights were sold so if you care about this election I would say find out how your Congressman who's running what their attitude is on this because we have alternatives in biofuels and conservation and other new new developments that could come along but if we're bribed you know to get that check every month here in South Carolina I'm afraid you know will continues in fossil fuels and my slogan is fossil fuels or fossil thinking yeah the the people who would have us burn all the fossil fuels are are clever you know what the problem is we should have started in the 1970s with with a small carbon price and gradually increased that and we would we would have much more efficient vehicles now and we would could have weaned ourselves largely off of fossil fuels but we we waited we wasted three decades now we're we've got to do it more rapidly but that frankly it we should be there's still so much potential inefficiency and again we're not tapping that because the prices are not that high the prices quickly went up and that's that's not the effective way to suddenly have an increase from two dollars a gallon to four dollars a gallon you need to gradually increase in price so that people have a chance to change their their energy uses but I think the oil in places like the Arctic National Wildlife Refuge incise should be left in the ground it would be we have time it gives you such a small amount of additional fuel for your addiction that we really need to break the addiction hi dr. Hansen thank you so much for visiting us I know that we've fought the oil battle on a national security basis and as a result of that a lot of people are pushing natural gas I have my suspicions that that won't really solve some other issues like climate change and I just wanted to know from an expert if my suspicions are accurate well natural gas is the most it has the least carbon of the three fossil fuels per unit energy and there doesn't appear to be so much of it that I mean we should be we're going to again it's a fossil fuel which is a finite source of energy so we're going to have to find alternatives on the long run that we should be working in that direction so you know it takes time to wean ourselves off of those but what we can't do for example is say okay well there are a lot of methane hydrates in the Arctic maybe we can go up there and figure out a way how to get the methane out of the methane hydrates if we did that there's a lot of methane there and we we could not do that without creating a different planet we would if we're going to try to use such methane we would have to capture the co2 and sequester it and again that's just such a hard thing to do that we had better figure out what our energy sources are going to be on the long run and move in that direction hi dr. Hanson um I just wanted to know what do you think is the most promising alternative energy source for the United States the most promising you know the most it turns out that the most promising and the least expensive is energy efficiency we're we use about double the amount of energy per unit product as as the more efficient places even California is almost twice as efficient as we are in terms of carbon emissions per unit GNP and in Europe is much more efficiently so we we've been wasteful we and we've because it was so inexpensive fossil fuels you know are very cheap and we as long as they don't have to pay for their damage so the air pollution the health effects and there are thirty to forty thousand people per year in the u.s. who died from air pollution most of which is from fossil fuel burn and there there's the climate impacts which will eventually have a big bill associated with them and the fossil fuels use doesn't have to pay for those and furthermore they even get tax subsidies so that's what makes them so cheap they don't have to pay for their true cost I forgot it was oh it was what is the cheapest so this efficiency is actually the the but that is not enough you got to have some energy and we should give the renewables the chance to fill that need and in order to give them that chance we need an improved electric grid which allows renewable energy to be moved from the places where it's abundant to the places where it's not so abundant and and that grid by the way could be underground right now we put all of our electric lines up and then we have to cut down the trees or cut half of the tree out and actually we would store more carbon if we allowed those trees to be there so it would we should have I think a a major program and I would hope the next president would have a major program to make a modern electric grid and and do it in a way which is environmentally more desirable and I think that we should let the marketplace decide on which are the most effective energy sources and if we have a carbon price that is gradually increasing and if it's made clear that this is going to continue to increase then there will be innovations that we haven't thought of yet we still have despite the fact that we've we've not done very well recently in terms of our science education and even or start to scare away some foreign scientists or at least we've always been very United say it's always been a very attractive place for people to come and so we've had a brain drain which has always been a positive brain drain we bring in scientists from all over the world and we need to make the u.s. a little more attractive but also train our students better and I think then we will come up with some things which I don't even know what they are yet I want to introduce the the nuclear issue and into the discussion here in South Carolina where we're facing four new nuclear reactors two of which possibly could be located north of Columbia by South Carolina electric and gas and in the company's application and I appreciate you were just talking about energy efficiency and conservation it's quite clear that the company intends to kill new measures in in their service area which is the the bulk of South Carolina for new types of energy conservation efficiency and they also intend to kill renewables in their service area and not do anything in application of about 200 pages the analysis on demand side management energy efficiency conservation and renewables is essentially about a page so they they plan to build the reactors which they claim would cost about 10 billion dollars but Department Energy estimated a couple weeks ago about nine billion dollars per reactor so it appears to me South Carolina could be going down a path where the big companies Duke and SC and G are gonna try to eliminate efforts for energy efficiency and conservation and my organization has intervened by the way Friends of the Earth against the SC ng proposal but it's quite disturbing to see that that this is what it appears they're they're out to do is stop any any renewables energy efficiency conservation in the state of South Carolina and I'm just curious how you think 18 billion dollars or more could best be invested over the next few years yeah that is analogous the situation in Nevada where I went several months ago and where there are plans to build three new coal-fired power plants which will provide a level of energy which makes it unnecessary to develop the renewable energies and they have incredible potential with solar and with wind and geothermal so Nevada should be a leader in these new renewable energies well that will be killed by if with the approval of those power plans and yet the governor and everyone is pushing for that and of course the fossil fuel industry and they're all in bed together that that and there's a reason for that from the utilities perspective that's the way they make the most money there and in this case in Hawaii Virginia that I mentioned that utility gets the guaranteed 14 percent return on whatever its costs are they're allowed to pass this on to the customer so it's just a crazy it's a wrong cyst a long wrong way of setting up the incentives because there's utilities make more money if they sell you more energy and they make more money if they build more power plants so that is what a leadership would have to address and they would have to buck the utility industry and the fossil fuel industry and that's a tremendous power that you're going up against I haven't seen the leadership that's willing to do that yet although you know that in California they're doing a pretty good job of that it's so it's possible but it has to be recognized where the who you're fighting and what needs to be done and yeah that you should should not be allowed to build a new large power plant whether it's coal or nuclear if you have not fully exploited the potential of energy efficiency and you know the programs that some of these companies have like Duke and their save a watt program are so marginal that and be and you know and to a certain extent you can't blame them because the rules are such that they make more they would make less money if they had a good program we got to change those rules I spend quite a lot of time arguing with climate sceptics I've come across quite a lot of them and I learned a lot from your talk and in particular the data and the graph that you showed of 50 million years of the impacts of co2 and as compared to the last 100 few hundred thousand years I know one of the questions I'm gonna get is how we estimated carbon dioxide levels from 50 million years ago yeah yeah and that's in our paper which will be published next week in the appendix in the supplementary material there we show all the data there like half a dozen different ways of trying to estimate how much co2 there was in the air probably one of the better ones is counting the stomata on the leaves of plants because from the fossil fossil plants because the plants don't like to have any more stomata than necessary they need to breathe in co2 through those stomata but as they breathe in the co2 they lose water vapor which is their vital fluid and so they try to minimize the loss of water and so you have these indirect type ways of measuring the co2 and all you can say for sure was that the co2 maximum back there was of the order of a thousand parts per million or maybe 1500 parts per million but it's it's not as accurate as you would like but it's clear that it was the dominant thing because as I showed the the other competing four scenes are an order of magnitude smaller I'm old enough to remember that what happened the last time an American president tried to tell the American people the truth about the unsustainability of our energy consumption Jimmy Carter was a one-term president and I don't see and maybe you can tell me what you know what else can be done but I don't see any way that we can make any substantial change in the problems that you're talking about tonight without accepting and moving toward a radically different lifestyle in the United States in the developed world unless we're willing to drastically reduce the human population of the world it seems that you know one or the other or both needs to occur do you see any realistic possibility that politicians who are more concerned about their political future than the future of humanity will actually tell the truth and work for policies that can bring about these changes yeah I well I yeah I see hope or I wouldn't be encouraging people to exercise the democratic process Jimmy Carter he had other problems and that probably caused his downfall not his honesty about the fuel he did recognize this energy problem and was encouraging measures to deal with it although some of them like coal gasification and things who are not probably the wisest but whether they you know they would they would have to bite this bullet of a carbon price and I think that the public is more intelligent and willing to understand an honest presentation of the facts especially if you'd packaged it in a way where the money is not going to Congress to decide who the favorites they're going to give it to it rather would go directly back to the public so I it seems to me that it's possible that but you're gonna have to have leadership from the top and they're going to have to understand the problem and they're going to have to the problem is a lot of the advice they get is from people who you know float through these special interests so it's not going to be easy but on the other hand that story is pretty clear and a smart person should be able to understand this so I think there's hope and dealing with it it's just a question of can we do it fast you know you talk about carbon sequestration before and I'm just wondering what are your thoughts on carbon sequestration is it viable is it not inherently dangerous my thought is it's probably technically possible to sequester co2 in geologic reservoirs where it would be quite safe from escape to the atmosphere but it's going to cost money and some of the disadvantages of coal are very difficult that mercury emissions is another story it's hard to you can reduce the mercury emissions but it's hard to eliminate them and the local effects of coal mining on mountain we especially if you do use mountaintop removal are not are pretty nasty in the pollution local lucien of streams and things so i my first my i would bet that if we put a carbon price on emissions that it will end up the coal gets mostly left in the ground and we find better cleaner ways for energy how'd the government regulate how much emissions the person has well so the person would have as much emissions as they want but they've got to pay for them the carbon tax and and the dividend that they would get is going to be the same as everybody else so if you you if you burn a lot of carbon you may George you're going to lose a lot of money and so you the marketplace would then solve it there would be no restriction on how much just as there isn't now there's no you can you can go out and drive as much as you want nobody's going to tell you you they have to can only drive 50 miles a day or whatever you can drive whatever you want but it's gonna cost a lot further you drive the more carbon you emit and the bigger your tax is well we don't need to measure it we just do we just what only thing we need is one number and that's the carbon tax the tax rate and as I say that would start moderate but it would increase with time and I used to say we need a carbon czar who would determine how it increases with time because you'd like it have intelligent decisions you if you're having a recession you don't want to increase the tax rate so you maybe go one year without increasing or whatever is necessary and if the prices of fuels drop like they sometimes do the supply increases then you in can increase the tax them because you don't want what the problem with renewable energies has been that whenever they start to look good then fossil fuel price drops and then the they can't compete the renewable energies can't compete so you'd want to choose the tax rate in an intelligent way but I was comparing the carbons are to the chairman of the Federal Reserve and I don't think he's done such a good job so maybe that's not a good example I guess it's a continuation of the previous question you talked about these carbons are and and that on one hand you emphasize that everything will be decided by the market forces which will lead to innovation and energy efficiency on the other hand you have these two measures which are non-market certainly the carbons are and then the changing of the structure of profits for utility companies how compatible is that and is there any methodology of actually calculating those carbon taxes which will be accepted by voters in public yeah the thing I actually like about the carbon price is that it is so simple and you know what I'm told by an economist right went to Kansas a few weeks ago is well you don't really have to worry then much about these complicated utility regulations because the carbon price itself will take care of that utilities are not going to use coal as an energy source if the carbon has the carbon tax gets higher and higher so you can you don't still I think and and efficiency I'm still not sure that you don't want some mechanism to and a stronger inducement for utilities to be encourage people to be as efficient as possible but the price that the consumer pays is going to be proportional to this carbon tax so there will be incentive for consumer to be efficient and so I think largely that one number takes care of it what is the carbon price and that should be determined empirically you will see will see as you're going along what is needed in order to reduce reduce the carbon emissions the fuel use exactly those are the kind of distortions that we have right now you got to eliminate all those distortions it we import food from New Zealand because there's zero tax in the 1940s the government's decided they should encourage the airline industry so they decided they had an agreement not to put a tax on aviation fuel and 60 years later they haven't changed that so that's crazy we should have a carbon tax and those kind of things would be fixed if in an automatic way if we did that there are several billion people on earth in the undeveloped countries that understandably would like to come up to our standard of living and the world's population is projected to grow from about 6 billion today to about 9 billion by the end of this century which is a big improvement over you know 10 years ago is projected to grow to ten and a half billion by 2050 nevertheless you know Japan seems to be about the most energy efficient developed country today produces about twice the GDP that we do per capita right for unit input of energy if you're not gonna do nuclear can solar energy support the coming demand for energy which would be roughly four to eight times the present use of energy worldwide well that that projection of four to eight times is the kind of thing the Energy Department's make I'm not sure that that's really viable they're projections always assumed this growth curve which if we in fact had a carbon price I don't think that curve would grow that way but but nevertheless there's two parts to your question I think population is one thing but you know having a lot of children has become unpopular with most women in educated women so that in developed in developed countries the fertility rate is actually many in most countries slightly below the replacement levels still population will go up because the life span is increasing but there are some countries in Africa and India where the growth rate is still pretty large but I yeah that's it's certainly a problem but it's one which has gotten better and we question is can solar do yeah it it would take substantial area there's actually enough area in a desert to do that but it's as I say it's not clear that renew that you would need a storage mechanism if you're going to use solar as the primary source because it is intermittent and you would need a good distribution system so it does raise the issue of whether you need other things but again I do think the market mechanism should decide that but the one question that everybody must know if do you need a base load power and if you do need a base load constant power is there a choice between are you do are you forced into making a choice between coal and nuclear power and I think that that I think that we should have continued research on next generation nuclear power the kind of nuclear power that would burn the 4th generation nuclear power that would burn nuclear waste and would not require us because we have so much nuclear waste already we wouldn't have to mine uranium for several hundred to a thousand years but that's not yet I'm not yet ready to advocate nuclear power I I think we haven't exploited energy efficiency or renewables to the anywhere near the extent that they're capable of providing so I think that should be the first priorities a comment and a question I think that what you said about reconstructing the grid is one thing that's really necessary as you were talking about do we really need to have base load generation and the the trend now I believe is moving away from the giant base load and moving into distributed energy systems and that's my comment my question is just to reveal my ignorance to everybody um I have difficulty in speaking to policymakers who want to speak to an expert such as yourself and I do not have the command of the facts and when I try to take something with me notes or you know I I get derailed because they have the opposition's arguments so my question is there are cliff notes that you have for people because you know there are policy makers tend to know even less than I do but I have to know a lot more than I do to be convincing since my background is not science it's not mathematics and it's someone thank you yeah I wish we had better cliff notes than we do you're actually thinking of writing some this winter but yeah that's that's the problem afraid I don't have a recommendation for a specific book that really handles what you what you want much of your data is collected by NASA satellites and as I understand it do the budgetary cuts etc of some of the satellites that were programmed to be put up in orbit are no longer going to be ones that take the measurements that you've been talking about is that a major problem that you foresee in the near future yeah that's a problem in that there's a Kadim II committee that wrote a report trying to stress the the problem with the great reduction in the satellite missions for looking at the earth and the fact that in the current administration there was a Polish there was a decision made that NASA should focus on going back to the moon which meant some people thought was in order to spend to take away the emphasis on looking at the earth because it rather not look at something if you don't know about it it's not a problem I would hope that in the next administration there would be a little more emphasis because there are really spectacular measurements like this gravity satellite and there's no follow-on satellite for that that's on the books and there are other things we can can do with modern technology which should be done and and you're right the number of earth looking satellites has been on the decline a market by itself can be competitive that can hit the edge to make an offer in person use market you find money with money and that language has the biggest spoken to these people for that reason they have done so well right now renewables are still if with the price of oil dropping renewables are at a disadvantage and suddenly the big investments in them are not looking as good or declining so that's why you need to make the fossil fuels pay for the damage that they're doing if you had at least remove their subsidies and and put some price even on the damages that they caused a human health and if not the climate then renewables would do very well and on the long run I think renewables will do very well but you know far we've we've had century to build up the technology for the fossil fuels the oil man of long-standing t boone pickens has proposed a plan to assist our dilemma at least as he puts it by reducing the amount of gasoline that we burn in cars automobiles and other forms of transportation and trading that gasoline for natural gas replacing the amount of natural gas that we would be using for the generation of electricity by wind power I have some I have some problems with that I don't see that it's really helping the transportation industry except that the natural gas does produce less carbon dioxide than gasoline but we're still we're still facing our transportation on fossil fuels yeah and it seems to me that all we're doing is all that problem all that proposed solution would be doing would be just giving us a little bit a little bit more time to continue doing what we've been doing in the past yeah yeah no I agree with you completely that the half of his plan is useful to trying to really see what we can get out of wind power in this wind belt in the central us but vehicles we're gonna have to find a way people are not going to give up personal vehicles that's just to grade a asset and so we have to find a way to power our vehicles which does not produce co2 and there certainly are ways to do that the electric car with electricity coming from non-fossil fuels is one way but as by itself has a limited range and you know there are other possibilities there's an interesting one mentioned in the recent book of tom police which is boron you know you if you if you put even if you could use iron dust and and if you make it fine enough powder it'll burn boron and fine powdered boron will burn and boron oxide and produce the energy to drive your car and you catch the boron oxide and then you take it back and put energy into it and take the oxygen off and you got the boron again well that actually would work and you could you could get the bore you could buy the boron in a set eleven store so you that would that would eliminate the need for gas station so you can be sure that the fossil fuel industry is going to be I'm very excited about this this buddy but there are ideas like that which would work on the long run the only reason we have not really developed them or worked on them is that fossil fuels are so cheap you drill into the ground and hit an oil pocket when you can bring the oil out for you know it used to be ten cents a gallon and and sell it for a lot more so yeah so we so I don't think that using natural gas to power gasoline to power vehicles is a long-run solution at all shall we call it I could bring it to a close now dr. Hansen I do want to say to you first of all I want to thank you all for coming and that there are some refreshments outside the door if you if you want to get your energy up again but I dr. Hansen I do want to thank you so much for sharing your time with us and sharing your thoughts and your knowledge it's just been a great honor for us to have you here