James Hansen, 70, heads the NASA Goddard Institute for Space Studies in New York City, a part of the Goddard Space Flight Center in Greenbelt, Maryland. He has held this position since 1981. He is also an adjunct professor in the Department of Earth and Environmental Sciences at Columbia University.Well I don't know why you say I'm alarmist. I just go by what the IPCC report says. And we have measurements of the carbon dioxide concentration. That's uncontroversial. And the projections of the temperature rise towards the end of the century if we go on burning fossil fuels like before is anything between one-and-a-half and six degrees. That's because the science is uncertain. But the important point there is that when people talk about a mean temperature rise of say two, three or four degrees that's a sort of global average which really is a signature of large scale change in climatic patterns. And for instance one of the computer models for a four degree temperature rise would give rise to a 10 degree temperature rise in Africa. And bear in mind also that in the depth of an ice age the mean temperature drop compared to the present was five degrees. So these changes are serious and the risk of them is substantial. And I think unless one has strong reasons for discounting the whole of this science then the precautionary action which was called for in the lead-up to Copenhagen, which the G8 has endorsed, which some countries in the European Union have endorsed of aiming to cut back on CO2 emissions over the next 40 years is fully justified as an insurance policy against the worst case…Well it's a cost benefit analysis. I think if you look at the present uncertainty I would say that the worst case is what we should take precautions against…And you have to compare the downside of the 50 per cent probability outcome with the downside of the worst 10 per cent of possible outcomes. But I think that it's really a concern to avoid the worst case… And particularly of course the higher the temperature of the earth rises the greater the chance of positive feedbacks like release of methane from the tundra when it melts and melting the Greenland ice cap etc . And that's why the consensus at the G8 meeting last summer was that the aim should be to ensure that the global temperature doesn't rise by more than two degrees. And that was the motive for trying to cut back with an aim of reducing global CO2 emissions by a factor of two by the year 2050.
http://www.abc.net.au/sundayprofile/stories/2857306.htm
Martin Rees has a simple message for those seeking solace in the stars. The end is nigh: humanity has only a 50-50 chance of surviving the 21st century. According to the Astronomer Royal, nuclear war, biological terrorism, ecological mayhem or asteroid collisions could take us out in less than 100 years. Nor should these warnings be dismissed as the musings of a mere depressive. They are the considered thoughts of one of the world's greatest astrophysicists, a man who has used his cosmological expertise to bring a new awareness of the risks to Earthly life. Outlined in his latest book, Our Final Century, Rees's prognostications demonstrate the perspective gained when our antics are viewed from an astronomical perspective. (Forget the asteroids, at the end of the day, it's most likely to be the A-bombs that do for us, he concludes.)…Most of our nuclear power plants are old and will soon need decommissioning, he points out. Will we replace them with new nuclear plants, or wind turbines, or turbines that burn Russian gas, or what? 'The government cannot fudge this one any longer,' Rees insists…Should we get it wrong, then we could face a cold uncertain future with insufficient power to warm our homes. On the other hand, we could enhance global warming and trigger climatic mayhem, or we could even suffer a devastating nuclear meltdown. These are uneasy prospects. Rees, to his credit, has perfect credentials for dealing with them.
http://www.guardian.co.uk/science/2005/ ... on.comment
In the book "Our Final Century" published in 2003 in the chapter concerning natural causes he predicted an imminent Japanese earthquake with huge tsunami and the relative repercussion in the economy of that country. This event came true in 2011 with the addition of atomic disaster.
Curt Stager, is an ecologist, paleoclimatologist, and science journalist with a Ph.D. in biology and geology from Duke University (1985). He has published over three dozen peer- reviewed articles in major journals.The scientific method and perspective have relevance that reaches beyond pure science. The urgency of implications for energy policy is not yet adequately recognized by governments, but it must be. The implications for intergenerational equity deserve greater attention…But the human-made rate of change is today about 2 ppm per year, about ten thousand times greater than the natural rate. So the assertion that we should not be concerned about human-made climate change, because there have been much larger natural climate changes is nonsense. There have been larger changes, but on very long time scales. On any time scale of interest to humanity, humans will be in charge of the climate change. The second conclusion is that we cannot burn all the fossil fuels, which would double or triple the amount of CO2 in the air, without setting the planet on a course to the ice free state. It would be a rocky trip, and it would take some time, as the ice sheets collapsed and sea level rose 250 feet. But it should not be doubted – feedbacks work in both directions – ice sheet formation is reversible…The Venus syndrome is the greatest threat to the planet, to humanity’s continued existence….If the planet gets too warm, the water vapor feedback can cause a runaway greenhouse effect. The ocean boils into the atmosphere and life is extinguished…There may have been times in the Earth’s history when CO2 was as high as 4000 ppm without causing a runaway greenhouse effect. But the solar irradiance was less at that time. What is different about the human-made forcing is the rapidity at which we are increasing it, on the time scale of a century or a few centuries. It does not provide enough time for negative feedbacks, such as changes in the weathering rate, to be a major factor. There is also a danger that humans could cause the release of methane hydrates, perhaps more rapidly than in some of the cases in the geologic record. In my opinion, if we burn all the coal, there is a good chance that we will initiate the runaway greenhouse effect. If we also burn the tar sands and tar shale (a.k.a. oil shale), I think it is a dead certainty.
http://www.columbia.edu/~jeh1/2008/AGUB ... 081217.pdf
Milankovic climate oscillations help define climate sensitivity and assess potential human-made climate effects. We conclude that Earth in the warmest interglacial periods was less than 1°C warmer than in the Holocene. Goals to limit human-made warming to 2°C and CO2 to 450 ppm are not sufficient – they are prescriptions for disaster. Polar warmth in prior interglacials and the Pliocene does not imply that a significant cushion remains between today's climate and dangerous warming, but rather that Earth today is poised to experience strong amplifying polar feedbacks in response to moderate additional warming. Deglaciation, disintegration of ice sheets, is nonlinear, spurred by amplifying feedbacks. If warming reaches a level that forces deglaciation, the rate of sea level rise will depend on the doubling time for ice sheet mass loss. Satellite gravity data, though too brief to be conclusive, are consistent with a doubling time of 10 years or less, implying the possibility of multi-meter sea level rise this century. The emerging shift to accelerating ice sheet mass loss supports our conclusion that Earth's temperature has returned to at least the Holocene maximum. Rapid reduction of fossil fuel emissions is required for humanity to succeed in preserving a planet resembling the one on which civilization developed…Augmentation of peak Holocene temperature by even 1°C would be sufficient to trigger powerful amplifying polar feedbacks, leading to a planet at least as warm as in the Eemian and Holsteinian periods, making ice sheet disintegration and large sea level rise inevitable….
We find that simulated western Arctic land warming trends during rapid sea ice loss are 3.5 times greater than secular 21st century climate-change trends. The accelerated warming signal penetrates up to 1500 km inland. BAU scenarios result in global warming of the order of 3-6°C. It is this scenario for which we assert that multi-meter sea level rise on the century time scale are not only possible, but almost dead certain. Such a huge rapidly increasing climate forcing dwarfs anything in the peleoclimate record. Antarctic ice shelves would disappear and the lower reaches of the Antarctic ice sheets would experience summer melt comparable to that on Greenland today…Hansen (2009) points out a negative feedback that comes into play as ice discharge approaches a level of the order of a meter per decade: cooling of the upper ocean by the ice. That negative feedback would be cold comfort. The high latitude cooling and low latitude warming would drive more powerful mid-latitude cyclonic storms, including more frequent cases of hurricane force winds. Such storms, in combination with rapidly rising sea level, would be disastrous for many of the great world cities and devastating for the world's economic wellbeing and cultural heritage…We have presented evidence in this paper that prior interglacial periods were less than 1°C warmer than the Holocene maximum. If we are correct in that conclusion, the EU2C scenario implies a sea level rise of many meters. It is difficult to predict a time scale for the sea level rise, but it would be dangerous and foolish to take such a global warming scenario as a goal…We have presented evidence in this paper that prior interglacial periods were less than 1°C warmer than the Holocene maximum. If we are correct in that conclusion, the EU2C scenario implies a sea level rise of many meters. It is difficult to predict a time scale for the sea level rise, but it would be dangerous and foolish to take such a global warming scenario as a goal
http://arxiv.org/abs/1105.0968
How close we are to destabilizing frozen methane is unclear. There are already signs of an accelerated release of methane from high-latitude tundra and from the larger reservoir on continental shelves. So far the amounts of methane released has been small. But if we continue to increase greenhouse gas emissions, the eventual destabilization of large amounts of methane is a near certainty. We must remember that the human-made climate forcing is not coming on just a bit faster than natural forcings of the past; on the contrary, it is a powerful rapid blow, an order of magnitude greater than any natural forcings that we are aware of….Global chaos will ensue when increasingly violent storminess is combined with sea level rise of a meter and more. Although ice sheet inertia will prevent a large sea level rise before the second half of the century, continued growth of greenhouse gases in the near term will make that result practically inevitable, out of our children’s and grandchildren’s control. (his grandchildren appear to be 4 & 1 year old at the time)….the sun remains in the deepest solar minimum since accurate solar record keeping began in the 1970s…The picture has become clear. Our planet, with its remarkable array of life, is in imminent danger of crashing. Yet our politicians are not dashing forward. They hesitate; they hang back. Therefore it is up to you…It is crucial for all of us, especially young people, to get involved. Source: Storms of my Grandchildren 2009.
James Lovelock, 91, CH, CBE, FRS, is an independent scientist, environmentalist and futurologist. He is best known for proposing the Gaia hypothesis, which postulates that the biosphere is a self-regulating entity with the capacity to keep our planet healthy by controlling the chemical and physical environment.Don’t panic and don’t give up. Climate change is a troubling and complex issue, but it’s not going to kill us all off, either…We need to think, speak, and act rationally if we’re going to deal successfully with the enormous social and environmental problems facing us…Were already near the limits of economically viable petroleum production, and the decline of cheap oil will have swift and sever consequences for those who will inherit the full measure of the problem. If and when the prices and availability of petroleum-based fuels, fertilizers, plastics, pharmaceuticals, cosmetics, synthetic fabrics, and even roadway pavement go haywire, the scale of human suffering could outstrip anything in the works for us from climate. It is that horribly dangerous and fast-approaching situation that makes the need for a switch to fossil fuels a no-brainer of the first order…from a full Anthropocene perspective, coal is too valuable and damaging to burn indiscriminately. It’s highest use is as a long term climate protection device, not just cheap and dirty furnace food. Running power plants on it is like burning to your house down because its cold outside. It’s like cutting a square of fabric from the floor of your raft to patch a hole in your trousers. In short, it’s just…well, it’s kind of stupid. Source Deep Future 2011
Brian Fagan, Professor emeritus of Anthropology at the University of California. He is the author or editor of 46 books, including seven widely used undergraduate college texts, and has contributed over 100 specialist papers to many national and international journals.By 2040, parts of the Sahara desert will have moved into middle Europe. We are talking about Paris - as far north as Berlin. In Britain we will escape because of our oceanic position.If you take the Intergovernmental Panel on Climate Change predictions, then by 2040 every summer in Europe will be as hot as it was in 2003 - between 110F and 120F. It is not the death of people that is the main problem, it is the fact that the plants can't grow — there will be almost no food grown in Europe. We are about to take an evolutionary step and my hope is that the species will emerge stronger. It would be hubris to think humans as they now are God's chosen race….The great climate science centres around the world are more than well aware how weak their science is. If you talk to them privately they're scared stiff of the fact that they don't really know what the clouds and the aerosols are doing...We do need scepticism about the predictions about what will happen to the climate in 50 years, or whatever. It's almost naive, scientifically speaking, to think we can give relatively accurate predictions for future climate. There are so many unknowns that it's wrong to do it. Source: Wiki bio.
Lovelock believes global warming is now irreversible, and that nothing can prevent large parts of the planet becoming too hot to inhabit, or sinking underwater, resulting in mass migration, famine and epidemics. Britain is going to become a lifeboat for refugees from mainland Europe, so instead of wasting our time on wind turbines we need to start planning how to survive. To Lovelock, the logic is clear. The sustainability brigade are insane to think we can save ourselves by going back to nature; our only chance of survival will come not from less technology, but more… Nuclear power, he argues, can solve our energy problem - the bigger challenge will be food. "Maybe they'll synthesise food. I don't know. Synthesising food is not some mad visionary idea; you can buy it in Tesco's, in the form of Quorn. It's not that good, but people buy it. You can live on it." But he fears we won't invent the necessary technologies in time, and expects "about 80%" of the world's population to be wiped out by 2100. Prophets have been foretelling Armageddon since time began, he says. "But this is the real thing."…Interviewers often remark upon the discrepancy between Lovelock's predictions of doom, and his good humour. "Well I'm cheerful!" he says, smiling. "I'm an optimist. It's going to happen."… There have been seven disasters since humans came on the earth, very similar to the one that's just about to happen. I think these events keep separating the wheat from the chaff. And eventually we'll have a human on the planet that really does understand it and can live with it properly. That's the source of my optimism." What would Lovelock do now, I ask, if he were me? He smiles and says: "Enjoy life while you can. Because if you're lucky it's going to be 20 years before it hits the fan."
http://www.guardian.co.uk/theguardian/2 ... matechange
“We have to understand that the Earth system is now in positive feedback and is moving ineluctably toward the stable state of one of the past hot climates. I can’t stress to strongly the dangers inherent in the systems in positive feedback. The year 2040 is when the IPCC is estimating that Europe, America, and China become uninhabitable for the growth of food, they’re grossly underestimating the rate of temperature rise, so that 2040 may be 2025. People don’t realize how little time we’ve got. The planet really is on the move. I don’t think there’s much doubt at all now amongst these few of us that have worked on the problem, that the system is in the course of moving to its stable hot state, which is about 5 degrees Celcius globally higher than now. Once it gets there, negative feedback sets in again, and the whole thing stabilizes and regulates quite nicely. What happens is, during that period, the ocean ceases to have any influence on the system, or hardly any. It’s run entirely by land biota. That’s what happened in the past anyway. There’s a good deal of geologic evidence; the best evidence comes from the 55-million-years-ago event. The Arctic ocean temperature was 23 degrees Celcius (73 F) – crocodiles swam around in it. The whole damn planet was tropical,probably, and will be again if it goes the way its going. The equatorial regions were a hell of a lot drier than they are now. You see that happening already…Oh I think it will be less than a billion [carrying capacity]. It will be too hot to grow. The world will move to its hot state regardless of what we do. Peter Cox at the Hadley Centre in our country has done some very careful analysis on how little CO2 is needed to start the automatic jump from the cool to the hot state, and its an astonishing and worryingly small quantity. He probably doesn’t want to be quoted. It turns out to be a quarter of a gigaton of carbon per year. So you’d have to cut back below that level to keep it stable, and you wouldn’t succeed if it’s already on course up towards it’s hot state. You’re not going to turn it back.” Source: Whole Earth Discipline 2010.
The range of forecasts by the different models of the IPCC is so large that it is difficult to believe they are reliable enough to be used by governments to plan policy for ameliorating climate change…Long term climate history of the Earth reveals the existence of several stable but quite different climate states, and their presence is not predicted in present day climate models…[Since 1970 until 2007], the measured sea level has risen 1.6 times as fast as was predicted. Similar but lesser discrepancies exist with the predictions of temperature…Observations of the area of the Arctic Ocean covered in summertime by floating ice. In 1980 and the previous years the area covered at the end of September showed 10 million sq. Km. The range of predictions compared to observed decline is huge, and suggests that if melting continues at this rate summer Arctic Ocean will be almost ice free within fifteen years. The IPCC prediction suggests that this is unlikely before 2050..The authors [Jeffrey Polovina] comment that the barren area of ocean has increased by 15% in the past nine years and this is a consequence of global heating. Lee Kump warned of its inherent positive feedback…this phenomenon is not yet included in their models by climate professionals. Source: The Vanishing Face of Gaia 2009
Gwynne Dyer, 68, Officer of the Order of Canada, is a London-based independent Canadian journalist, syndicated columnist and military historian. Dyer writes a column on international affairs which is published in over 175 papers in at least 45 countries.A study by Britains authorative Hadley Centre for climate change documented a 25% increase in global drought during the 1990s, which produced well documented population losses. The Hadley’s computer model of future aridity resulting from the impacts of greenhouse gas emissions are truly frightening. At present, extreme drought affects 3% of the earths surface. The figure could rise to as high as 30% if warming continues, with 40% suffering from severe droughts, up from the current 8%. 50% of the worlds land would experience moderate drought, up from the present 25%. The UNEP reports that 450 million people in twenty nine countries currently suffer from water shortages. By 2025, an estimated 2.8 billion of us will live in areas with increasingly scarce water resources. 20% of the worlds population currently lack access to safe, clean drinking water. Contaminated water supplies are a worse killer than AIDs in tropical Africa. If projected drought conditions transpire, future casualties will rise dramatically. The greatest impact will be people living in already arid and semiarid lands, about a billion of us. The number of food emergencies in Africa each year has already tripled since the 1980s, with one in three people across sub-Saharan Africa malnourished….
Today, we are experiencing sustained warming of a kind unknown since the Ice Age. And this warming is certain to bring drought – sustained drought and water shortages that will challenge even small cities – to say nothing short of metropolises like Los Angeles, Phoenix, and Tucson. The Ogallala aquifer, an enormous underground aquifer, that supplies eight states from Nebraka to Texas, is being depleted at a rate of 42 billion gallons a year. When one hears that an expanding Las Vegas is trying to buy up water supplies from the outlying Nevada ranches, one wonders what the future will hold. Will a day come when the hotels on the Strips run dry because the aquifers have run dry?…By 2030, UNESCO estimated the world will need 55% more food, which translates into growing demand for irrigation, which already claims 70% of all water consumed by humans…Now we confront a future in which most of us live in large and rapidly growing cities, many of them adjacent to rising oceans and waters where Category hurricanes or massive El Ninos can cause billions of dollars of damage within a few hours. We’re now at a point where there are too many of us to evacuate, where the costs of vulnerability are almost all beyond the capacity of even the wealthiest governments to handle. The sheer scale of industrialized societies renders them far more vulnerable to such long term changes as climbing temperatures and rising sea levels. Source: The Great Warming 2008.
Steven Chu, 63, American physicist and the 12th United States Secretary of Energy. Known for his research at Bell Labs in cooling and trapping of atoms with laser light. Nobel Prize in Physics in 1997.Here are four conclusions that I have reached after a year of trailing around the world of climate change. First, this thing is coming at us a whole lot faster that the public acknowledged wisdom is. When you talk to the people at the sharp end of the climate business, scientists, and policy makers alike, there is an air of suppressed panic in many of the conversations. We are not going to get through this without taking a lot of casualties, if we get through it at all. Second, all the stuff about changing light bulbs and driving less, although it is useful for raising consciousness and gives people some sense of control over their fate, is practically irrelevant to the outcome of this crisis. We have to decarbonize our economies wholesale, and if we haven’t reached zero greenhouse gas emissions by 2050 – and preferably 80% cuts by 2030 – then the second half of this century would not be a time you would choose to live in…Third, it is unrealistic to believe that we are really going to make those deadlines. Maybe if we had got serious about climate change fifteen years ago, or even ten, we might have had a change, but its too late now. Global greenhouse gas emissions were rising at about 1% when the original climate change treaty was signed in 1992, now they are growing at 3% a year, and most of Asia, home to half of the human race, is rapidly moving into industrialized consumer societies. To keep the global average temperature low enough to avoid hitting some really ugly feedbacks, we need greenhouse gas emissions to be falling be falling by 4% now, and you cant turn that supertanker around that fast. So we are going to need geoengineering as a stop-gap to hold down the temperature while we get our emissions down, and we should be urgently examining our options now…Fourth, for even degree that the average global temperature rises, so do the mass movements of populations, the number of failed states, and very probably the internal and international wars. Which, if they become big and frequent enough, will sabotage the global cooperation that is the only way to stop the temperature from continuing to climb. Source: Climate Wars 2008
David King, 71, FRS, is the Director of the Smith School of Enterprise and the Environment at the University of Oxford, Director of Research in Physical Chemistry at the University of Cambridge, Director of the Collegio Carlo Alberto, Chancellor of the University of Liverpool and a senior scientific adviser to UBS. He was the Chief Scientific Adviser to Tony Blair and Gordon Brown and Head of the Government Office for Science from October 2000 to 31 December 2007.In a worst case, Chu said, up to 90% of the Sierra snowpack could disappear, all but eliminating a natural storage system for water vital to agriculture.“I don’t think the American public has gripped in its gut what could happen,” he said. We’re looking at a scenario where there’s no more agriculture in California. I don’t actually see how they can keep their cities going….He compared the situation to a family buying an old house and being told by an inspector that it must pay a hefty sum to rewire it or risk an electrical fire that could burn everything down.“I’m hoping that the American people will wake up,” Chu said, and pay the cost of rewiring.
http://climateprogress.org/2009/02/04/c ... ia-part-2/
Peter Ward, paleontologist and professor of Biology and of Earth and Space Sciences at the University of Washington. Ward's academic career has included teaching posts and professional connections with Ohio State University, the NASA Astrobiology Institute, the University of Calgary, McMasterI see climate change as the greatest challenges facing Britain and the World in the 21st century. In a speech given by the Prime Minister on 27 April 2004, he agreed that in the long term it will be the single most important issue we face as a global community. Over the past century the global climate has warmed by an average of 0.6C, with much of this seen over the past 30 years. The science is clear that this rise in temperatures will continue and will accelerate, leading to a rise in the range of 1.4C to almost 6C by 2100. At the same time, global average sea levels are also predicted to rise, by between 9 to 88 cm by 2100. At over 370 parts per million, we are already living with levels of carbon dioxide in the atmosphere that have not been seen on earth for at least 420 thousand years. The current level isalready well beyond that seen in the atmosphere during Earth’s “warm periods” between ice ages, and is consistent with the Earth’s “hot periods”, such as around 60 million years ago when all ice on the planet melted and when mammals would have found Antarctica one of the most comfortable places to live.
http://www.coolkidsforacoolclimate.com/ ... 20King.htm
The Iraq war was the first ‘resource war’ according to Professor Sir David King, Director of the Smith School of Enterprise and the Environment and a former UK government chief scientist.‘I believe historians of the future will look back and see the Iraq war as the first resource war of the 21st century,’ he told the British Humanist Association in a speech on February 11. ‘The US is dependent on oil and was well past peak oil production when the war began. Looking at Iraq, many in the White House saw an opportunity to secure America’s oil supply by creating a friendly government which would be more amenable to providing oil to the US.’….‘Now, we face a new set of linked challenges including producing enough food, protecting biodiversity and supplying enough energy, water and minerals. If we try to tackle these problems individually we will fail.’ Our challenges now are entirely different from those faced by Darwin and Dickens in the 19th century. Now, we face a new set of linked challenges including producing enough food, protecting biodiversity and supplying enough energy, water and minerals. Professor King warned that the world’s rapidly increasing population will make these problems far worse. He pointed out that we are currently releasing 36 billion tonnes of carbon dioxide a year. ‘We will need to produce 50 per cent more food by 2030, including 50 per cent more crops. At the same time there will be much less water. Put simply we will have to get more crop per drop.’
http://www.ox.ac.uk/media/news_stories/2009/090213.html
University, and the California Institute of Technology. He was elected as a Fellow of the California Academy of Sciences in 1984.
Rajendra Pachauri,70, Nobel Peace Prize, head of Yale's Climate and Energy Institute, former Chair of the Intergovernmental Panel on Climate Change.Will there be another extinction similar in any way to the events of the deep past profiledin this book? If one is in our future, when might it occur? For the momentlet us accept an affirmative answer for the first and see what (ifany) consensus there already is regarding the second.The latter question was examined in a landmark paper publishedin Nature in 2005. That study estimated that climate changes brought about by global warming will lead to the extinction of more than amillion species by the year 2050. Since there are only 1.6 million species now identified (although many more are yet to be described), such numbers result in an extinction rate of more than 60 percent. To compare this with the past, this number would place the next greenhouse extinction second only to the Permian extinction. And the first million species, if the Nature study is correct, would just be the start of things. As we shall see below, a shift to a new kind of oceanic conveyer current system would create an anoxic ocean, eventually changing into a Canfield ocean. The shift from mixed to anoxic ocean would likely kill off the majority of marine species, just as it has in each of the ancient greenhouse extinctions…..The rise in sea level that has occurred to date is still very low, on the order of a centimeter over the last century. But if either part of the Antarctic (western part) or all of the Greenland ice sheet melts, which would occur (according to climate models) with a global rise in temperature of between 2 degrees and 3 degrees Celsius, the rise in sea level would be 6 meters, or about 20 feet! If both melt, the rise is more than 60 meters, or 200 feet. Good-bye, all coast cities, and goodbye, a good proportion of the planetary agricultural yield, since a very significant quantity of human food is grown in the large deltas such as those found at the ends of the rivers Nile, Mississippi, and Ganges.
All of the deltas and their rich soil would be pretty well inundated with even a 1- to 2-meter rise in sea level. The eventual rise of 25 meters would bring back the old coastlines of the Eocene epoch. Melting of the ice sheets would produce a radically different climate than what we have now. Radically different. As stressed here, what we call climate is made of many individual and largely interconnected systems, and the past evidence of change suggests that these thresholds are both sensitive and can have dramatic consequences, once a critical level is passed…..Warm water has more salt ions, and once it cools, its density is higher than surrounding water. But the injection of fresh water, with a much lower density because of its lack of salt ions, would effectively stop the conveyer or perhaps shift where it starts and stops on the surface. A rising sea level would drowncities, but a conveyer belt shift would kill people, lots of them, because
of the great effect it would necessarily have on climate in European agricultural areas. It can be surmised that a suddenly cooled, cropless European subcontinent with its large population would by necessity look toward still-arable lands to make up food loss. Here’s hoping under this scenario that the Europeans have enough cash in reserve to buy an awfully large volume of food for centuries to come…As any urban geographer can attest, a large proportion of humanity currently resides in coastal or low-elevation riverside locales. All such localities would be affected by even a small rise in sea level, and when we start looking at 25-foot increases (a common estimate for an ice-free world following melting of the Greenland and Antarctic ice sheets), we see a reality in which vast populations of humans will have to move to higher ground. Perhaps nowhere is this more evident than in the low-lying country of Bangladesh,which currently has one of the densest populations of humans on Earth and whose population is estimated to double over the next century. Let us look in detail at what a 25-foot rise in sea level would do to that country…
Virtually the entire population of Bangladesh, one of the poorest countries in the world, would have to migrate. But who would take the perhaps 200 million people who would need land, food, water, and energy on an unprecedented scale…A 2004 study by scientists at the World Health Organization and the London School of Hygiene and Tropical Medicine determined that 160,000 people die every year from the effects of global warming, from malaria to malnutrition, children in developing nations seemingly the most vulnerable. These numbers could almost double by the year 2020….Our world sits on a knife edge of global starvation already. We six billion humans [7 now?], heading toward a far higher number at about the time that rising carbon dioxide levels should begin to stabilize a new pattern of climate, are able to be fed, all of us right now, through the miracle of that long-ago breakthrough of the human mind, agriculture. We need every bushel of grain, however. There cannot be even a single season without harvest in either hemisphere, and this is why there is extreme danger of rapid weather change if there is a Krakatoa-type volcanic explosion or impact of a 100-meter or larger asteroid. Both would put so much dust in the air that one hemisphere or the other (or perhaps both) would have a yearlong or longer winter and thus no crops. Short-term climate change would be nearly as devastating, and in the long run, more devastating. Neurobiologist Bill Calvin, who has written extensively on the dangers and effects of sudden climate change, suggests that a 10- to 20-year event is far more difficult to deal with societally than is a sudden catastrophe. Source: Under a Green Sky 2007
I don’t think climate change can make us go extinct. Unless we produce so much CO2 in the atmosphere that, once again, we shut down the conveyor belt currents. These are the largest scale currents in the ocean. They are from the surface to the bottom currents, not just sideways currents. And so, there the current conveyor that takes oxygen from the top and takes it to the bottom, if we lose that, then the bottoms of the ocean go anoxic and you start down this road towards what we call a greenhouse extinction, which is the hydrogen sulfide events. It would take tens of thousands of years to get to that. But we as a species who have only been around for a couple of hundred thousand years, the average mammal lasts 5 million years. Are we anything less than average? So, we should have a few million years left even if we’re average, and we’re not average. We could be living fossils that last 500 million years. There’s nothing genetically within us that says we have to go extinct, unfortunately, I have these genes in me that are going to kill me and all your listeners too. But as a species we don’t have those genes. Species don’t age out of existence, species are killed off, lose competition, they go extinct because they’re driven to extinction. It’s not inherent. It’s not within them….So we keep track of Mother Earth and do some good engineering and we’re not going to go extinct. But extinction and misery are two different things. Not going extinct doesn’t mean you’re not going to be miserable, and by misery I mean, wholesale, enormous human mortality. The greatest single threat to us, again, is this rapid global warming, in the sense that I am really kept up at night worrying about the slowing of the circulation systems of the oceans and kept up at night worrying a great deal about sea level rise.
http://bigthink.com/ideas/18406
...a mean sea level rise of two meters would suffice to virtually submerge the entire country of 1,190 small islands, most of which barely rise two meters above sea level. That would be the death of a nation…....have raised the threat of dramatic population migration, conflict, and war over water and other resources, as well as a realignment of power among nations. Some also highlight the possibility of rising tensions between rich and poor nations, health problems caused particularly by water shortages and crop failures.…He said that since the panel began its work five years ago, scientists have recorded “much stronger trends in climate change,” like a recent melting of polar ice that had not been predicted. “That means you better start with intervention much earlier.” How much earlier? The normally understated Pachauri warns: “If there’s no action before 2012, that’s too late. What we do in the next two to three years will determine our future. This is the defining moment.”
(I interpret this as we can't avoid catastrophic climate change, but we can still avoid extremely catastrophic climate change)
Peter Wadhams Professor of Ocean Physics, Head of the Polar Ocean Physics Group in the Department of Applied Mathematics and Theoretical Physics, University of Cambridge.
Lord Monkton,59, is a British politician, public speaker, former newspaper editor and hereditary peer. Formerly a member of the Conservative Party, Monckton has been the deputy leader of the UK Independence Party since June 2010. Funding connected to Exxon-Mobil.Peter Wadhams, professor of ocean physics at the University of Cambridge, said much of the melting will take place within a decade, although the winter ice will stay for hundreds of years. “The data supports the new consensus view -- based on seasonal variation of ice extent and thickness, changes in temperatures, winds and especially ice composition -- that the Arctic will be ice-free in summer within about 20 years," Wadhams said in a statement. "Much of the decrease will be happening within 10 years.”
http://ca.reuters.com/article/topNews/i ... 8W20091015
Dear John, I agree with your diagnosis of the serious role that methane is going to play in the next phase of global warming, but fear that Semiletov is right in his statement that we can do nothing (so long as stupidity and greed prevail in the world of course, but unfortunately that seems to be a given). The unfortunate fact is that two big factors are driving Arctic methane release: (1) The general increase in global temperatures (enhanced by a factor of 2-3 in the Arctic) as a product of our CO2 emissions, which is causing permafrost to melt on land, (2) the summer retreat of sea ice from continental shelves, which allows the shallow shelf seas to warm by up to 5C right down to the seabed in summer, causing offshore permafrost to melt and release trapped methane. The sea ice retreat is itself a result of global warming via mechanisms involving both air temperature and ocean heat transport. Therefore what is causing methane emission, both on land and at sea, is our heating of the atmosphere due to CO2 emissions. The dangerous difference about today is that the heating has just become enough to trigger massive releases (eg the seabed warming) while in the past it was not. A quantum jump is about to happen. There seems to be no prospect of reducing our CO2 emissions, or even of reducing the rate of rise in our CO2 emissions. The greens may think they have won some battles in building wind farms and making us sort our rubbish, but this is pitiful deckchair-rearrangement compared with the fact that China is building four coal-fired power stations per week and is set to continue to do this ad infinitum since they have plenty of coal and have taken over the world's manufacturing industry.
Greed and blindness continue to govern our stewardship of the planet, and I fear there is no solution except the climate-driven collapse of our entire global civilisation. If geoengineering can do something to slow this, then great. My own fears for any technique involve (a) unknown side effects, (b) the fact that it is like putting a sticking plaster on a gigantic wound, in that it is slowing the temperature rise while doing nothing about the driving force, the CO2 content of the atmosphere. Processes that depend only on CO2 rather than temperature will continue apace, e.g. acidification of the ocean, leading to loss of the marine ecosystem. CO2 sequestration would seem to be the only geoengineering that would be really safe and productive in the long term. However the energy required to get rid of CO2 itself has to be generated, and this has to be by non-emissive methods like nuclear or renewable. But if you are going to do this you have solved the problem anyway since you are no longer emitting the CO2 that is causing the problem! Sorry to seem pessimistic but I do fear the worst. I suspect that in 20 years time we will be seeing a range of serious impacts making the world a quite different (and nastier) place than it is now. One of them will be the loss of summer sea ice (I think this will happen in less than 10 years). At my age I will, sadly, be seeing just the beginning of the collapse of our planetary civilisation, but I fear that our grandchildren will live (or not love) through the whole thing, Best wishes Peter Wadhams
http://groups.google.com/group/geoengin ... 8f72b369d#
Fred Singer, 88, Austrian-born American physicist and emeritus professor of environmental science at the University of Virginia.[1] Singer trained as an atmospheric physicist and is known for his work in space research, atmospheric pollution, rocket and satellite technology, and as an outspoken critic of the mainstream scientific assessment of global warming. Linked to Exxon, Shell, GM, Sun Oil, utilities, Philip Morris, accepted payment by fossil fuel industry for global warming consultation and climate-denial conferences.Monckton questions the magnitude of global warming to be expected in response to anthropogenic increases in CO2 concentration. Monckton has stated his belief that there is a greenhouse effect, that CO2 contributes to it, that humanity is adding CO2 to the atmosphere and that some warming will result, but he questions how much warming will occur, how much damage it will do and whether addressing it by taxing or regulating CO2 is cost-effective.In a 2006 article he questioned the appropriateness of using a near-zero discount rate in the Stern Review, which, he wrote, had underestimated the costs of mitigation and overstated its benefits. He said that mitigation was "expensively futile without the consent of the Third World's fast-growing nations
scm - 25, pilot, permaculturist, soon-to-be reservist.Singer argues there is no evidence that the increases in carbon dioxide produced by humans cause global warming, and that if temperatures do rise it will be good for humankind. He told CBC: "It was warmer a thousand years ago than it is today. Vikings settled Greenland. Is that good or bad? I think it's good. They grew wine in England, in northern England. I think that's good. At least some people think so. "We are certainly putting more carbon dioxide in the atmosphere, However there is no evidence that this high CO2 is making a detectable difference. It should in principle, however the atmosphere is very complicated and one cannot simply argue that just because CO2 is a greenhouse gas it causes warming." He believes that radical environmentalists are exaggerating the dangers. "The underlying effort here seems to be to use global warming as an excuse to cut down the use of energy," he said. "It's very simple: if you cut back the use of energy, then you cut back economic growth. And believe it or not, there are people in the world who believe we have gone too far in economic growth.
Myself and a friend are trying to get a group of people to build up some electric bicycles and cycle across Canada towing banners saying "-80% by 2050", "NUCLEAR/SOLAR" "GEOENGINEERING", "350 PPM CO2"- for the purposes of raising awareness of this critical issue.The third world will not stop their populations from skyrocketing, but we can stop ours. China, Brazil, and India will not stop industrializing, but we can lead the way in clean energy. Coal plants built today will not simply be decommissioned, so we should support nuclear in the northerly latitudes where there is little sun, and solar in the southerly latitudes where there is much sun. The poor world may cut down their forests to grow food (and export, cattle-feed, and lumber...), but we can keep ours. Other countries may erode their soils into the air and ocean, but we don’t have to – we can bring about sustainable farming by combining genetic engineering with organic and permaculture practices. We can save our organic wastes and build up our yard soils for the day that we really have to start growing our own food, and we can start experimenting now with small gardens and rainwater capture systems. The vocal anti-nuclear minority will sabotage the future of the majority – so we may have an overheated planet, brown electricity, and old-coal and gas plants burning CO2 into the air driving us towards a runaway feedback loop – an H2S event or Venus condition. We’re not going to stop using liquid fuels for our 400 million vehicles, but we can drive less and buy smaller and electric cars. We can put pressure on politicians to support geoengineering, genetic engineering, carbon-capture, emissions-cuts, pedestrian & bicycle friendly cities, and clean nuclear and solar energy. Fusion is still at least 50 yeas away from commercialization, but nuclear power is mature now, and Integral Fast Reactors can be online in a matter of decades. We could have had them already had the Gore-Clinton admin not cut it. Numerous scientist confirm that a mix of both is required if we are to achieve 80% emissions cuts by 2030, In the rich world, population will come down through family planning and birth control, or by imposed limits. It is our choice.