That's the critical point and it needs to be made clearly and backed up with evidence. Further, you need to PROVE that the arctic sea ice is the tipping point.
A 2008/12/3 John Nissen <[EMAIL PROTECTED]>: > > Gwynne and everybody, > > One additional point to make it absolutely clear about why we need > geoengineering. I'll number this zero, so it begins the chain of argument: > > 0. Even if we were to stop all CO2 emissions overnight, the CO2 level in > the atmosphere would remain at around 385 ppm, and the net positive climate > forcing (i.e. heating) around 1.6 Watts per square metre, for decades. The > global warming would therefore continue for decades. Therefore there is no > way that emissions reductions can produce a cooling effect on a timescale of > a few years. > > Actually the point can be made even stronger. To produce a cooling effect, > one would need to have a net negative forcing. To produce this you would > need to bring the CO2 down below the pre-industrial equilibrium point, > generally taken as 280 ppm. And to do this in the Arctic, and counter the > local albedo forcing, you'd need to take CO2 well below 280 ppm within a few > years. This is clearly absolutely impossible. > > And as regards geoengineering "as a last resort" [1], when do you determine > the time that you should use it? When you can see that other methods are > not working, surely. That was probably in the mid 80s, when the glacier > mass ice loss suddenly deviated from the curve it had previously followed - > showing a doubling of global warming per decade [2]. This sudden > acceleration could not be explained by CO2 - but could have been explained > either by the additional forcing of Arctic sea ice which had started to > retreat, or by the removal of "pollutant" sulphur compounds from the > atmosphere, or a combination of the two. (I discussed this with the glacier > expert Wilfred Haeberli himself, to no definite conclusion.) We should then > have realised that putting sulphate aerosol in the stratosphere was an > obvious way to stop the acceleration, as it could counter both the effect of > sulphur removal from the troposphere AND any additional forcing of Arctic > sea ice. > > But it is easy to be wise in hindsight. Now we have no time to lose as the > sea ice threatens to disappear faster than we ever imagined possible. > > Cheers from Chiswick, > > John > > [1] Paul Crutzen has considered albedo enhancement a last resort: > www.springerlink.com/content/t1vn75m458373h63/fulltext.pdf > > [2] Glacier mass ice loss. Haeberli et al. See trend on figure 1b: > http://www.wgms.ch/mbb/mbb9/sum06.html > > > > ----- Original Message ----- > From: John Nissen > To: Gwynne Dyer > Cc: geoengineering > Sent: Wednesday, December 03, 2008 3:58 PM > Subject: Fw: [geo] Can't Get There from Here > > Hello Gwynne, > > I appreciate very much that you explore the security dimension. But there's > one vital thing you miss. > > You write: > > "The third conclusion is that there is a point of no return after which > warming becomes unstoppable—and we are probably going to sail right through > it. It is the point at which anthropogenic (human-caused) warming triggers > huge releases of carbon dioxide from warming oceans, or similar releases of > both carbon dioxide and methane from melting permafrost, or both. Most > climate scientists think that point lies not far beyond 2 degrees C hotter > (3.6 degrees F). " > > but you miss the glaring example of a tipping point - the disappearance of > the Arctic sea ice. So here is a logical argument. Considering: > > 1. The Arctic is warming at least double the speed of average global > warming. > > 2. If the sea ice goes, the Arctic warming accelerates and is liable to > trigger huge releases of methane from permafrost, long before the global > warming reaches 2 degrees. (It is also liable to trigger disastrous sea > level rise from Greenland ice sheet melting.) > > 3. According the latest research, documented in the Climate Safety report > (launched last week [1]), the sea ice could disappear in 3-7 years (at the > end of summer). > > 4. Geoengineering now appears to be the only possible means to save the > Arctic sea ice, and prevent a "tipping point" becoming a "point of no > return". > > 5. The local climate forcing (heating) from the albedo effect, as Arctic > sea ice retreats in summer, could more than double between now and complete > sea ice disappearance. > > 6. Geoengineering needs to be up to full scale as quickly as possible, to > maximise the chance of saving the Arctic sea ice. > > Therefore: > > 7. We need immediately to initiate a top-priority, super-urgent project for > geoengineering to save the Arctic sea ice - a project with the focus, > determination and urgency of the Manhattan project. > > The consequences of failure are too dreadful to contemplate. Failure is not > an option. Psychologically, we have to think of this as war, in order to > accept the enormity of the predicament we are in and be spurned to action. > > > Can you refute this argument? Can anybody refute this argument? > > Could Obama and his defense advisers accept this argument? (I shall work on > our own Prime Minister Brown.) > > Cheers from Chiswick, > > John > > [1] http://www.indymedia.org.uk/en/2008/12/414238.html > > > > ----- Original Message ----- > From: Alvia Gaskill > To: [email protected] > Sent: Wednesday, December 03, 2008 2:08 PM > Subject: [geo] Can't Get There from Here > Like the financial crisis, when the roof falls in, watch out, it may be your > own. > > http://www.straight.com/article-173168/gwynne-dyer-four-harsh-truths-about-climate-change > > > Gwynne Dyer: Four harsh truths about climate change > > By Gwynne Dyer > Publish Date: December 2, 2008 > > About two years ago, I realized that the military in various countries were > starting to do climate change scenarios in-house—scenarios that started with > the scientific predictions about rising temperatures, falling crop yields, > and other physical effects, and examined what that would do to politics and > strategy. > > The scenarios predicted failed states proliferating because governments > couldn't feed their people; waves of climate refugees washing up against the > borders of more fortunate countries; even wars between countries that shared > the same rivers. So I started interviewing everybody I could get access to: > not only senior military people but also scientists, diplomats, and > politicians. > > About seventy interviews, a dozen countries, and eighteen months later, I > have reached four conclusions that I didn't even suspect when I began the > process. The first is simply this: the scientists are really scared. Their > observations over the past two or three years suggest that everything is > happening a lot faster than their climate models predicted. > > This creates a dilemma for them, because for the past decade they have been > struggling against a well-funded campaign that cast doubt on the phenomenon > of climate change. Now, finally, people and even governments are listening. > Even in the United States, the world headquarters of climate change denial, > 85 percent of the population now sees climate change as a major issue, and > both presidential candidates in last month's election promised 80 percent > cuts in American emissions of greenhouse gases by 2050. > > The scientists are understandably reluctant at this point to publicly > announce that their predictions were wrong; that they are really much worse > and the targets will have to be revised. Most of them are waiting for > overwhelming proof that climate change really is moving faster, even though > they are already privately convinced that it is. > > So governments, now awakened to the danger at last, are still working to the > wrong emissions target. The real requirement, if we are to avoid runaway > global warming, is probably 80 percent cuts by 2030, and almost no burning > whatsoever of fossil fuels (coal, gas, and oil) by 2050. > > The second conclusion is that the generals are right. Food is the key issue, > and the world food supply is already very tight: we have eaten up about > two-thirds of the world's grain reserve in the past five years, leaving only > 50 days' worth in store. Even a one degree C (1.8 degrees F) rise in average > global temperature will take a major bite out of food production in almost > all the countries that are closer to the equator than to the poles, and that > includes nearly all of the planet's bread-baskets. > > So the international grain market will wither for lack of supplies. > Countries that can no longer feed their people will not be able to buy their > way out of trouble by importing grain from elsewhere, even if they have the > money. Starving refugees will flood across borders, whole nations will > collapse into anarchy—and some countries may make a grab for their > neighbours' land or water. > > These are scenarios that the Pentagon and other military planning staffs are > examining now. They could start to come true as little as 15 or 20 years > down the road. If this kind of breakdown becomes widespread, there will be > little chance of making or keeping global agreements to curb greenhouse gas > emissions and avoid further warming. > > The third conclusion is that there is a point of no return after which > warming becomes unstoppable—and we are probably going to sail right through > it. It is the point at which anthropogenic (human-caused) warming triggers > huge releases of carbon dioxide from warming oceans, or similar releases of > both carbon dioxide and methane from melting permafrost, or both. Most > climate scientists think that point lies not far beyond 2 degrees C hotter > (3.6 degrees F). > > Once that point is passed, the human race loses control and cutting our own > emissions may not stop the warming. But we are almost certainly going to > miss our deadline. We cannot get the ten lost years back, and by the time a > new global agreement to replace the Kyoto accord is negotiated and put into > effect, there will probably not be enough time left to stop the warming > short of the point where we must not go. > > So—final conclusion—we will have to cheat. In the past two years, various > scientists have suggested several "geo-engineering" techniques for holding > the temperature down directly. We might put a kind of temporary chemical > sunscreen in the stratosphere by seeding it with sulphur particles, for > example, or we could artificially thicken low-lying maritime clouds to > reflect more sunlight. > > These are not permanent solutions but merely ways of winning more time to > cut our emissions without triggering runaway warming in the meanwhile. > However, the situation is getting very grave, and we are probably going to > see the first experiments with these techniques within five years. > > There is a way through this crisis, but it isn't easy and there is no > guarantee of success. As the Irishman said to the lost traveler: If that's > where you want to go, sir, I wouldn't start from here. > > Gwynne Dyer will be speaking on his new book, Climate Wars, at the Park > Theatre (Cambie and 18th) in Vancouver on December 6 and 7 at 1 p.m. Tickets > available from www.festivalcinemas.ca/ or at the door. > > ________________________________ > Source URL: > http://www.straight.com/article-173168/gwynne-dyer-four-harsh-truths-about-climate-change > > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "geoengineering" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/geoengineering?hl=en -~----------~----~----~----~------~----~------~--~---
