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Comments 57051 to 57100:

57051. dissembly at 12:58 PM on 9 July 2012
       Ian Plimer Pens Aussie Geologist Gish Gallop #2 of the Week
       @Tom Curtis - "The minimum cost of your plan amounts to the equivalent of an increase of the GST to 15% plus a 5% tariff on all exports; or alternatively, a 10 year depression (very low or negative growth for 10 years)." Bizarre. Neither a 10-year depression nor an increase to the GST are equivalents of each other, and neither is directly equivalent to any of the many other ways in which a public works campaign can be funded. This is either extremely naive on your part, or extremely poorly intentioned. The fact is, an increase in progressive taxation (not even remotely like raising the GST) could fund a substantial amount of this plan. The mining tax alone would have netted billions more under Rudd's scheme than Gillard's, a genuinely progressive mining tax would have done better again. A recent estimate held that even under a UK-like tax system, another $108 billion per annum would be available in the Australian budget. But your statements are incorrect from the other direction, as well; a massive public works campaign would stimulate the economy (and, in fact, is precisely what many economists advocate during recession), and the economics of nationalisation make the process both cheaper and less wasteful (and entirely removes one of the glaring holes in the carbon cap & trade scheme - simply because you try to incentivise investment doesn't mean investors will actually do what you need them to do, and in fact, right now they are hoarding their money against a rainy day; you can lead a horse to water, but you can't make it drink). You seem to believe that an economy is a bucket that can be filled and unfilled, and nothing else. But progressive taxes are different to flat taxes, and government spending is different to private spending. And again, you seem to be arguing not simply that the carbon tax is a good idea, but that alternatives don't exist - a ridiculous position, but especially from someone who seems to think it's worthwhile spreading information about global warming. You wrote: "If you do not have a realistic plan to persuade a major party, and the majority Australians to vote for these consequences as part of your plan before the end of this electoral cycle, you do not have an alternative plan to the Carbon Tax." Again, a naive and unrealistic assessment of how politics works, and one which ignores each and every point I made on this subject in earlier postings. A "realistic plan" is not limited to an electoral cycle (as governments can be pressured at any stage during their tenure) & not limited to a political party (as parties only deal with the situation they face). Furthermore, and once again, the carbon tax is not an alternative plan to what I've outlined - it, in fact, makes the plan I've outlined more difficult, by sucking strength from the push for alternative energy as a way to address climate change. That's why the government of the day proposed it, and that's precisely the effect it has had on the environmental movement. Regarding the graphs; thank you for linking me to the source. It appears that this is not related to any specific model of a given carbon pricing scheme (as i incorrectly thought), but in fact, is modelling carbon trading between countries based on their respective energy budgets; it's dependent upon the emissions trading actually being relatively unproblematic, which in turn depends very heavily on the nature of carbon offsets, which in turn depends on what alternatives are developed in any given country. The graph describes the target we want to reach. Well, great! The argument is about how to get there. I am familiar with the second graph you posted, in fact I just saw it in Beyond Zero Emission's "Zero Carbon Australia" - a plan that outlines the theoretical capacity to completely eliminate fossil fuels from Australia's energy grid within ten years.
57052. Ger at 12:04 PM on 9 July 2012
       Climate change is simple: We do something or we’re screwed
       In transferring the knowledge into the society, one does wonder why it takes so long for anything is being accepted in some societies. I think http://www.kellogg.northwestern.edu/faculty/sapienza/htm/social_capital_jeea.pdf is a good reading for that.
57053. Tom Curtis at 11:01 AM on 9 July 2012
       Climate change is simple: We do something or we’re screwed
       TonyO @23, on the contrary, it is still on the cards that we could tackle global warming at a cost that does not preclude continuing economic growth (see my immediately preceding post). It is urgent, however, that we stop dawdling about doing so. A further 10-15 years of inaction will make your prognosis accurate.
57054. Tom Curtis at 10:59 AM on 9 July 2012
       Climate change is simple: We do something or we’re screwed
       rpauli @22, the primary constraint on human well being, at least in material terms, is the energy available to meet those material needs and desires. Currently humans use enough energy for that purpose to generate 0.028 W/m^2 of energy globally. In contrast, we receive an average of 240 W/m^2 from the Sun. That means we could increase our energy use from renewable sources till it used just 1% of energy from the Sun that arrives at Earth and expand our energy consumption by a factor of 85. It would be preferable if that expansion came without a concurrent expansion in population so that we could expand our energy consumption (and hence wealth) per capita; but it is not necessary. Scenarios of doom and gloom because of a need to switch to renewable energy are therefore completely unwarranted. Nor is there an immediate need to stop population growth (although there is a need for population to stabilize within the next century). Nor are the prospects of doom from Global Warming so certain that we cannot afford a measured approach. That measured approach requires that we immediately and unilaterally (for all Western nations) end emissions growth and start reductions at at least 3% per annum by 2015 as the prelude to negotiating a global agreement to reduce effective global emissions to zero by 2050. It does not mean simply cutting of all combustion of fossil fuels, which would introduce a human disaster worse than any in prospect from global warming.
57055. Tom Curtis at 10:15 AM on 9 July 2012
       Hansen and Sato Estimate Climate Sensitivity from Earth's History
       curiousd @35, transient climate response (TCR), the Charney Sensitivity, aka, the Equilibrium Climate Sensitivity (ECS), and the Earth System Sensitivity (ESS) all have clear definitions in computer models. The Earth System Sensitivity is the change in temperature with a doubling of CO2 with constant forcing after the system has reached equilibrium, allowing all feedbacks fast and slow to operate. The Equilibrium Climate Response is the change in temperature with doubled CO2 and constant forcing after the system has reached equilibrium with only fast feedbacks allowed to operate. The transient climate response is the average temperature in the twenty year interval centered on the year that CO2 reaches double the initial value when it is increased by 1% per annum throughout the model run. Outside of models, we cannot control things so easily. CO2 increases at greater than 1% per annum, and not be the same percentage each year. Fast feedbacks and slow feedbacks both occur. However, the TCR as scaled for the appropriate forcing still approximates to the current expected temperature during a period of increasing CO2. The scaled ECS still approximates to the temperature we can expect a hundred or so years after CO2 emissions begin to be held steady. And the scaled ESS approximates to the temperature the Earth will be at if CO2 concentrations are held near constant over thousands of years. In each case, however, they are only approximations. In any event, the time it takes for the deep ocean to warm is not a feedback. It is only a constraint on the response time.
57056. Tony O at 09:39 AM on 9 July 2012
       Climate change is simple: We do something or we’re screwed
       We are committed to change much worse than that which has destroyed previous civilizations. To make matters worse our super economic efficiency has, in many cases, been at the price of resilience. We are so much more vulnerable than most realize. It would appear whatever happens, we are committed to much pain. It is still possible that a better system will arise out of the ashes, but the transition will be horrific. The longer we carry on as we are the less will come out at the other end. The steps we need to make will also change society in a way that will help us get through it all. This is the change that conservatives fear above all and why they are so reactionary. Carry on as we are without any action and by the end of the century we will have set in motion changes that will in all probability claim humanity itself. This is less scary to the conservative mind than changing the concept of property. They truly believe better dead than red, and they have a pretty wide definition of red.
57057. Tom Curtis at 09:32 AM on 9 July 2012
       Roy's Risky Regression
       Alexandre, an introduction to the basic information can be found in the article What is causing the increase in atmospheric CO2?. For the data on volcanic emissions, the article Do volcanoes emit more CO2 than humans? is a good start point. Anthropogenic Emissions from Land Use change and deforestation represent 10% of all human emissions (0.9 PgC of 10 PgC). Over the last century, human caused deforestation and other land use changes have been by far the largest cause of change in land cover, and hence natural changes cannot be significantly larger than that (and in fact are known to be a net sink of CO2 by the mass balance argument).(Source) Evidence that CO2 rise coincides with the start of industrialization is found in ice cores (Scroll to bottom for thousand year record), and also in other markers, including sponges: (Source) A little discussion of the O2 decline may be helpful. Because the change in solubility of O2 in water with change in temperature significantly differs from that of CO2, the change in O2 concentration is not effected by other possible CO2 sinks. That means the decline in CO2 concentration means any large unknown natural sources of CO2 must not come from a source of combustion but must come from a low C14 source generated by photosynthesis. These facts together almost completely preclude the existence of such putative natural sources. Because of the importance of the O2 decline, it is worthwhile lookinig at the chart below from the IPCC TAR which shows it: The observed decline in O2 is straighforward. The diagonal arrow from the start point marked "fossil fuel burning" represents the expected change in CO2 and O2 concentrations from known fossil fuel consumption. The arrow marked "ocean uptake" represents the uptake of CO2 by the ocean, which does not effect the O2 level. The arrow marked "land uptake" is the uptake of O2 by photosynthesis, which also reduces O2 concentration. Finally, the small arrow marked "outgasing" represents outgasing from of O2 from the ocean, which does not effect CO2 concentration. That outgasing is partly the result of a warming ocean, and partly a result of the very slight decrease in the partial pressure of oxygen in the atmosphere. These factors are reasonably well, but not exactly known. The most important fact is that because the fall in O2 concentration is significantly less than that predicted from known combustion of fossil fuels, the uptake of CO2 by photosynthesis must exceed the combustion or decay of modern organic material from either anthropogenic (Land Use Changes) or natural sources.
       Moderator Response: TC: word "corals" deleted and "sponges" added.
57058. r.pauli at 08:42 AM on 9 July 2012
       Climate change is simple: We do something or we’re screwed
       Great post. But we should realize that "Do Something..." does not mean wimpy-ass dumb tweaks to business-as-usual. ("OK, I'll bring a cloth bag to the supermarket" ) Nope, our tepid compromises mean nothing. ( OK we will try carbon cap and trade - but only if we keep up profits.) Nor does it mean we can try smart actions too late. ("OK, if you insist, a carbon tax - but that's all I will accept.) No, we cannot let runaway climate change begin. It really means no more carbon combustion - none. And we have to sequester carbon. Oh and no more hockey stick Population growth. None. No more humans ("OK, we'll accept 1.5 children per family [but only voluntarily!]") The wonderful thing about physical laws of climate science is that there really is no room for compromise. We are defeated, and all we can do is mitigate this defeat to a level that may permit multigenerational survival. No negotiations. We can only decide now how difficult we want to make it. Sorry, no compromises.
57059. Tom Curtis at 08:39 AM on 9 July 2012
       Murry Salby's Correlation Conundrum
       Bob Loblaw @31, as an addendum to your (2), the natural source must not be pure source of Carbon or a hydrocarbon that has been combusted. Otherwise the O2 concentration would be falling 10 times faster than it currently is. So, it must come from ancient plants (to account for the changes in C13 ratio and C14 ratio) but it must not be combusted. Therefore it can only be leakage from pure subterrainian reservoir of fossil CO2. The immediate problem is that no such reservoirs have been noticed; and buried organic materials do not form CO2 in large amounts because they are cut of from a ready supply of oxygen.
57060. Bob Loblaw at 08:28 AM on 9 July 2012
       Murry Salby's Correlation Conundrum
       Marco: OK. Let's assume that there is a natural source we don't know about. What characteristics would it have to have, to be the main cause of the increasing atmospheric CO2? To begin, we know that at least 50% of the anthropogenic emissions are removed, because the rate of increase is only 50% of those emissions. With that 50% amount, all the rise is anthropogenic. So, if only part of the rise is anthropogenic, then we need a natural sink that removes more than 50% of our anthropogenic source. Let's make a WAG that only 10% of the rise is anthropogenic, which requires that 95% of the emissions be removed (i.e., the 5% that is not removed is 1/10 of the rise that equals 50% of the emissions). The natural source then has to make up the other 90%. What are the implications of this? 1) if natural sinks are just as efficient at removing this natural source as they are at removing the anthropogenic source, then this natural source has to be 9X larger than the anthropogenic one. (9+1=10, x5% not removed, leaves 0.5 as the atmospheric rise). This would be extremely unlikely to have gone unnoticed. 2) in addition, the natural source has to have the same isotopic signature as the anthropogenic source. It has to smell, taste, look like CO2 from fossil fuels. 3) to get away from 1), you need to find some plausible physical mechanism whereby CO2 from a natural source - CO2 that is indistinguishable from fossil fuel-derived CO2 - is somehow not soaked up by a sink that efficiently removes the anthropogenic source. This is akin to magic. Bluntly, the whole argument of an "unknown" natural source that is causing the increase, while the anthropogenic one is easily counteracted by natural sinks, is a dog that just won't hunt.
57061. Tom Curtis at 08:01 AM on 9 July 2012
       Climate change is simple: We do something or we’re screwed
       fungelstrumpet @19, the strategy of ignoring the A in AGW is doomed to failure. The simple reason is that "their favourite colmnist" is sure to also be telling them that "it is the sun" and that solar scientists are predicting a Maunder Minimum, so the problem will magically go away; or perhaps that "it's a natural oscillation" which, having oscillated up is about to oscillate down and so will again magically disappear. What is worse, we, having neglected the A, will be unable to counter them, for it is the A that is the sole basis for our predictions of ongoing, and increasingly rapid warming. On top of that, you can be sure that "their favourite colomnist" will very quickly tell them, if we drop the A, that we were wrong about the A all along, and what else are we wrong about that we are not telling them. Like it or not, the only successful communication strategy has been, and remains the truth, the whole truth, and nothing but the truth.
57062. jimspy at 07:38 AM on 9 July 2012
       Climate change is simple: We do something or we’re screwed
       I'm with Funglestrumpet @19. Details, shmetails. All we laymen need to know to shut down the deniers is that it is them vs. the virtual unanimity of the climate science community. How often do 98% of scientists agree on anything? I think it's time to get beyond the debate stage, marginalize the naysayers, and pressure the world's leaders to act in unison. How on earth did we get past Y2K so smoothly? What process was used to kick everyone's tuchas on that issue? Whatever it was, we need more of it. (And I also agree we need to re-think nuclear. Yes, I'm fully aware of the dangers; I just think we're going to have to re-evaluate those dangers as "acceptable risks".)
57063. scaddenp at 07:27 AM on 9 July 2012
       It's the sun
       And as a final point - if we were getting warmer because we were getting closer to the sun, then we should see that in the TSI measurements. As shown in the main article, this is not the case.
57064. funglestrumpet at 06:58 AM on 9 July 2012
       Climate change is simple: We do something or we’re screwed
       One of the main problems with trying to convince the general public of the danger is the concentration on whether GW is AGW or not. They get hung up on that point and because they refuse to believe that we are to blame, they think we we cannot supply the solution. This is an easy position to adopt because it means no effort on their part and it helps them believe what their favourite colmnist has said in their daily/Sunday paper. Not only that, but it is happening very slowly in terms of human lifetimes, which is a deception, I know. However, if an asteroid were headed our way, would we just put our head between our knees and kiss our backsides goodbye, or would we try and do something? Even the general public would support action despite the fact that it is clearly not an asteroid of our making and the possible actions are far more limited than the current climate changes ones are. Also, even the thickest of newspaper columnists would support taking action in such circumstances. Well, having said that, there are a couple I can think of and a peer of the realm who would say it is nothing to worry about in order to get attention. So what am I recommending? Well, stop debating the 'A' in AGW. Take it as read that we are to blame and leave those who disagree to carry on the debate elsewhere, away from the mainstream. Push quantifying the precise long-term temperature effects of cutting GHG emissions within possible sensitivities to GHG (obviously narrowing the sensitivity band as sensitivity becomes more clearly constrained) and start a serious debate on alternative energy supply. In particular, lend support to Thorium nuclear reactors, which I believe the USA and China are now collaborating on. We simply cannot afford to take the 'If its nuclear, it must be dangerous and must not be used' approach. Not using it is damn dangerous if Mr Roberts is anywhere near correct in his prognosis. It would not hurt to start compiling a list of persons who we believe are against taking action for reasons that do not have a valid, ie not debunked, scientific foundation. The time might well arise when the only way to get some action is to get people facing charges of crimes against humanity. That might even shut up a certain attention seeking peer. Finally, David Roberts is correct when he says that we do not need to know the details in order to act. We know the science of the greenhouse effect and we know that we are pumping GHGs into the atmosphere. The dangers are clear and so too is the necessary action.
57065. llosmith at 06:43 AM on 9 July 2012
       Climate change is simple: We do something or we’re screwed
       Composer99 @13: The link in 10 should read LINK
       Moderator Response: [RH] Fixed link that was breaking page formatting.
57066. Kevin C at 06:15 AM on 9 July 2012
       Climate change is simple: We do something or we’re screwed
       Clyde: Have you read the IPCC SREX, rather than second hand reports of its contents? The material on Disaster losses is quite concerning, especially given the current fragility of the global economy.
57067. curiousd at 05:49 AM on 9 July 2012
       Hansen and Sato Estimate Climate Sensitivity from Earth's History
       Maybe I now know enough to make a slight correction to something someone told me(not sure who the someone was) here in one of many helpful answers to my questions. The recent pre print Hansen and Sato made available here states they determine a "fast feedback" response which includes CO2, water vapor feedback, sea ice, clouds, aerosols. The warming up of the entire ocean, (like the melting of Antarctica and Greenland)is longer term, on order of "100s of years" Someone - I think incorrectly - confused fast feedback response, which is a portion of the equilibrium response, with the "transient response". "Transient response" means you run a simulation to include continual addition of CO2, which, unfortunately, is what "really happens". Also, the warming up of the ocean is not included in either the fast feedback response or the transient response because it can take 1000 years for the ocean temperature to equilibriate with the surface?? Do I now have this right?
57068. Alexandre at 04:53 AM on 9 July 2012
       Roy's Risky Regression
       Tom Curtis at 08:22 AM on 8 July, 2012 That's a great summary! Do you have any link with that information so I can keep it as a reference?
57069. Clyde at 04:30 AM on 9 July 2012
       Climate change is simple: We do something or we’re screwed
       Paul Magnus 11 Even at the current rate of extreme events societies globally are going to collapse. We are just arriving at 1c. Not even there yet. The IPCC SREX report disagrees with your position. No strong evidence to support GW is causing "extreme" weather events. Read more here.
57070. ranyl at 04:08 AM on 9 July 2012
       Climate change is simple: We do something or we’re screwed
       How long is the lag in the system? For El Nino it seems about 6 months, for the sun it seems about 2 years, the Argus current takes 4-35 years to reach the North Atlantic, but what is the lag between CO2 forcing and heat realisation? Say it is only 20years for 80% warming like Hansen's suggests, then considering the rise in CO2 since 1990, 350ppm to 393ppm, or 35% or all humankind's CO2 emissions in the last 20 years, and the last 10 years has had low low sunspot activity, been shaded by the Asia smog and S02, with nitrogen fertilizes effects rducing warming further due to ozone formations from NO destroying methane and predominantly La Nina conditions and maybe things are sobering. And the man in the video never mention so much stuff as well, like waste, pollution, overexploitation, invasive alien's, methane re-rise, forest fires, the albedo accelerator that is kicking in terms of ice sheet surface, snow melt and sea ice loss. These weathee extremes are clearly serious and the last time USA hada major drought the whole economny sort of stopped, and let's face it the world's ecomony isn't that robust at present. How to do we get to 350ppm? And given paleo data that isn't that safe! Make the impossible possible he says? That would take a transformative scale change to all levels of society across the world. That seems impossible, unless everyone takes on board that environmental change is now and serious and is soemthign to do everything about otherwise the legacy we leave is civilization chaos which in past times has never been pretty. Adaptation is also needed to protct food and water security agaisnt the times. So a reasonable challenge, so like the man in the video says why isn't everyone making their primary drive to restore to 350ppm and to prepare for the changes to come?
57071. dagold at 03:29 AM on 9 July 2012
       Climate change is simple: We do something or we’re screwed
       I watched Robert's talk with interest. We clearly need to build a 'critical mass' of support to pressure the extraordinarily reluctant politicians to even begin addressing the problem. The 'educational' approach Roberts takes is important. But I am wondering if old fashioned story telling approaches might also be key. I am crafting a potential TED video that combines my personal health story- 2 serious diseases, multiple hospitalizations and surgeries- culiminating in a liver donor liver transplant from my brother. It has it all!- my initial 7 year denial of the scientists and the consequences (ambulance, hospitals, surgeries), systems being pushed out of equilibrium, complete with graphs of upward sloping liver function tests ('Keeling Curves!'), tipping points crossed, and, finally, maturing to the stage of facing the information, making the hard choices-asking a family member to donate over half their liver- and (for me) coming out to the other side...all in analogy to climate change. (please see 'My Personal Story' on www.itsphysics.org for more of the story) Coming soon to a theater near you.
57072. Composer99 at 01:20 AM on 9 July 2012
       Climate change is simple: We do something or we’re screwed
       Whomever can fix it: Tom Curtis' link @10 is broken.
       Moderator Response: TC: Fixed, and thanks for spotting it.
57073. Rob Painting at 18:49 PM on 8 July 2012
       It's the sun
       Icyhot - in addition to Tom's comments, the beauty of the mainstream climate science view of atmospheric CO2 as Earth's thermostat - is that it has explanatory power. Turn up the CO2 and the Earth gets warmer, turn it down and the Earth cools. Aside from maybe one outstanding complication, the Miocene, this relationship holds true for hundreds of millions of years back in time. There are, of course, other control knobs on Earth's climate - such as the Milankovitch Cycles, but CO2 is very clearly the Big Kahuna. If, as you suggest, the Earth is moving closer to the sun, why then was it much warmer on Earth further back in time?
57074. villabolo at 15:57 PM on 8 July 2012
       Nil Illegitimi Carborundum
       Giordano Hernandez I would have gone postal if all that vitriol were directed at me. Hang in there.
57075. Paul Magnus at 15:45 PM on 8 July 2012
       Climate change is simple: We do something or we’re screwed
       Here is a good article on current rate of extreme events http://thinkprogress.org/climate/2012/07/07/511194/what-is-causing-the-climate-to-unravel/
57076. Paul Magnus at 15:07 PM on 8 July 2012
       The GLOBAL global warming signal
       Here we have the graph of ghg well, co2 emissions.( I am sure that total ghg emissions is going to be much steeper) we can see that there is a marked up tick around 1945. http://thinkprogress.org/wp-content/uploads/2012/07/chart751.png I think that that might correlate quite closely to the the up tick in sea level rise rate acceleration, The next surge will be soon and must be related to the albedo effect in the article and it's effect on Greenland ice sheets. What seems likely in the south is massive collapse and disintegration. So the ice going tthere will result in a jump in sea level rise rathere than a rapid increase in rate,
57077. Stephen Baines at 15:04 PM on 8 July 2012
       Murry Salby's Correlation Conundrum
       DM. We're on the same page. The only rather academic difference is that I think conservation of mass is not a sufficient condition to argue that humans are the sole cause of the current increase in CO2. You also have to assume that removal processes do not distinguish between anthro and natural CO2 in the atmosphere. That assumption is implicit in the equations as you have presented them. Alternatively, one could characterize variations in atmospheric CO2 as a system of two distinct budget equations that track the anthropogenic CO2 and the natural CO2 in the atmosphere separately. One could then set the loss term for the anthro CO2 into one natural reservoir equal to anthropogenic emissions. In the other equation another natural reservoir could contribute CO2 to atmsophere while not interacting with the reservoir that serves as a sink for anthro CO2. Of course, in doing all that, one would be contradicting physical reality. Removal processes cannot distinguish between anthro and natural CO2 any more than my bank can discriminate between the dollars deposited as salary and those deposited from tax refunds once they are in my checking account. None of the evidence we have in hand suggests that atmospheric CO2 acts as anything other than single reservoir of well mixed gas with respect to loss processes. Still, I can't tell you how many people I meet are prone to think human derived CO2 must behave differently -- it's ingrained in their psyche.
57078. Marco at 15:01 PM on 8 July 2012
       Murry Salby's Correlation Conundrum
       Dikran, I fully agree that the natural environment is still resulting in a net uptake. I was merely pointing out that some may still claim, even after they accept the "net" versus "absolute", that there is a net natural emitter that is larger than the anthropogenic contribution. Better have arguments for that available, or they have another few hours to spread that new confusion!
57079. Paul Magnus at 14:55 PM on 8 July 2012
       Climate change is simple: We do something or we’re screwed
       @9 SW, I think we don't need much science to prove that 2c is way beyond the carrying capacity for global civilization. Even at the current rate of extreme events societies globally are going to collapse. We are just arriving at 1c. Not even there yet. Do you really think that another 1c is not going to be absolute mayhem? Then also add the accelerating sea level. Tusha. No need to even then address a 4c scenario.
57080. Tom Curtis at 13:55 PM on 8 July 2012
       It's the sun
       Icyhot @976: If the Earth's orbit decayed by one inch per annum since 1750, it would be 6.65 meters closer to the Sun, on average than in 1750. Incoming solar radiation varies with the inverse square of distance. So, a decay of 6.65 meters in the approx 150 billion meters radius of the Earth's orbit would result in a 0.00000001 increase incoming solar radiation, or a forcing of 0.000000024 W/m^2. This is compared to the approx 1.8 W/m^2 forcing from increased CO2 over the same period. Therefore such a decay in the Earth's orbit would not have a detectable effect the Earth's climate (and probably would not be detectable to begin with). However, that is beside the point. There is, SFAIK, no evidence that the Earth's orbit is decaying. Indeed, if anything the solar tide on the Earth would cause the Earth's orbital distance to increase, just as the Lunar tide result in the measured increase in distance to the moon. The increase in distance, however, is very small so that there is no reason to think the Earth's orbit will increase or decay significantly at any time in the past or future several million years.
57081. Tom Curtis at 13:04 PM on 8 July 2012
       Climate change is simple: We do something or we’re screwed
       Sceptical Wombat, the special report by the WGBU, Solving the Climate Dilemma: The budget approach, directly addresses the second point, and contains relevant discussion on the other two points.
57082. IcyHot at 13:02 PM on 8 July 2012
       It's the sun
       Hello Ladies and Gentlemen. What is the truth to the assertion/hypothesis that the Earth's orbit is degrading by approximately 1 inch per year. I am at a loss for the location of the publication that provided this information. I do find it curious. Have any of you interested parties read about or researched this hypothesis? Although I find myself wondering about the validity of the assertion/hypothesis, it would seem to be a logical,if not complete cause of warming. What would the effects of increased or decreased solar flare activity have on the Earth with this hypothesis. An interesting point for further investigation.
57083. Sceptical Wombat at 12:29 PM on 8 July 2012
       Climate change is simple: We do something or we’re screwed
       One of the problems with cross postings like this is that SKS's usual policy of justifying everything by references to the peer reviewed literature goes by the board. This is a pity and I think detracts from the quality of your site. Could anyone give me some references to justify the following: 2 degrees Celsius would be unbearable We have to start reducing emissions in 5 to 10 years We are on target to reach 4 degrees by the end of the century I'm not saying that the evidence is not there - I would like to be able to refer to it.
57084. newcrusader at 11:04 AM on 8 July 2012
       Climate change is simple: We do something or we’re screwed
       The heat across most of the eastern US (east of the Rockies to the Atlantic coast) has been historic. I know so many people that 'believe in global warming' but know so little about what is really happening. I have been looked at as 'alarmist' 'obsessive' discussing to others about the dire danger we are in. Now I am gloating - my attitude is simply...'I told you so' 'you snickered' at me and thought I was a 'radical environmentalist' trying to destroy the 'American way of life'. With C02 levels this high ( though this is in the pipeline) We are seeing Carbon in the atmosphere from 1990- or before before when C02 had passed 350ppm. As the decade progresses that warming in the pipeline will rear its ugly head. Is the climate beginning to unravel quicker then many thought? Perhaps- but there is really little time left to stop the worst outcomes that climate change will bring to us.
57085. Tom Curtis at 08:46 AM on 8 July 2012
       Climate change is simple: We do something or we’re screwed
       Sphaerica @2, uncertainty is often misinterpreted. Fake "skeptics" think that if the science is uncertain, the future will be less bad than scientists predict; but of course it may be much worse. On the other hand, we are only almost "out of time" if the scientist's predictions are accurate and not overestimating the problem. While the low side uncertainty exists, it is always too soon to say too late. (And while the high side uncertainty exists, it is never correct to say that we have time to spare.) This is also on top of Chris G @1, with whom I agree. One point that needs to be mentioned, however, is too late for what? Assuming scientists central projections are accurate: We are already too late to avoid a collision (zero damage from climate change), and passed that point around 1990. We are not yet too late to avoid the collision writing of our car, but if we don't brake now a our car is toast. If we don't mind the radiator being concentened into the rear fender, we still have time to spare. In this situation, policy settings around the world are for steady acceleration.
57086. sol6966 at 08:45 AM on 8 July 2012
       Roy's Risky Regression
       Rob, Stephen & Tom Thanks Sol
57087. Tom Curtis at 08:22 AM on 8 July 2012
       Roy's Risky Regression
       sol @18: Declining C14 ratio indicates old, hence fossil fuel or volcanic (ie, not oceanic outgasing or deforestation; Declining C13 ration indicates organic, hence not volcanic; Declining O2 concentration indicate combustion, hence not volcanic; Measured CO2 emissions from all (surface and beneath the sea) volcanoes are 1 hundredth of antrhopogenic CO2 emissions; hence not volcanic; Partial pressure of CO2 in the ocean is increasing, hence not oceanic outgassing; Known changes in biomass too small by a factor of 10, hence not deforestation; and as the icing on the cake, The start of the growth in CO2 concentration coincides with the start of the industrial revolution, hence anthropogenic; and Increase in CO2 concentration over the long term almost exactly correlates (corr.: 0.998; R^2: 0.997) with cumulative anthropogenic emissions: (Source) and finally, Annual CO2 concentration growth is less than Annual CO2 emissions, hence anthropogenic. In all, six independent lines of evidence preclude a volcanic source for the increased CO2; five independent lines of evidence preclude a source from the non-fossil biosphere; and three lines of evidence are only consistent with an anthropogenic source.
57088. DSL at 08:22 AM on 8 July 2012
       Climate change is simple: We do something or we’re screwed
       If George Monbiot (or, rather, Leonardo Maugeri) is right, the worst may have gotten much worse: http://www.monbiot.com/2012/07/02/false-summit/.
57089. Chris G at 06:57 AM on 8 July 2012
       Climate change is simple: We do something or we’re screwed
       ...nothing to be done about it anyway, ... as though we are already committed to the worst that could possibly happen, which I would like to think is not the case.
57090. Chris G at 06:53 AM on 8 July 2012
       Climate change is simple: We do something or we’re screwed
       Hi Sphaerica, If you put it that way, OK. It bothers me when people say that there is nothing to be done about it anyway, and the 'out of time' concept can be used (abused?) as leverage by them. I do not wish to give them any leverage.
57091. Dikran Marsupial at 06:34 AM on 8 July 2012
       Murry Salby's Correlation Conundrum
       Stephen Baines wrote "Strictly speaking, I'm sure one could construct a mathematical budget that could reconcile a natural source with a CO2 increase less than human emissions." No, this is not possible, without contravening conservation of mass. The increase cannot be less than human emissions without the natural environment as a whole taking in more CO2 than it emits. It is important not to confuse the cause of the rise with the source of the molecules actually in the atmosphere (yes, I know that sounds odd). There are vast exchange fluxes that swap CO2 from the oceans/terrestrial biosphere and atmosphere each year, so anthropogenic CO2 only lasts on average about 4-5years in the atmosphere. However the exchange is a straight swap, so it doesn't have any effect on the amount of CO2 in the atmosphere. In my paper I have a simulation of a very basic model of the carbon cycle that shows that even though the rise is 100% anthropogenic, only a small percentage of the excess in the atmosphere consists of CO2 of directly anthropogenic origin; this is a result of the exchange fluxes.
57092. Dikran Marsupial at 06:29 AM on 8 July 2012
       Murry Salby's Correlation Conundrum
       @Marco, even if some part of the natural environment had become a stronger emitter of CO2, and some other part a greater CO2 sink, the mass balance analysis still tells us that the natural environment is a net carbon sink, in which case how can it be causing the rise while taking more CO2 out of the atmosphere than it puts in? I think part of the problem is that the mass balance argument is so simple some find it hard to accept that it proves unequivocally that the rise is anthropogenic, but it does.
57093. Dikran Marsupial at 06:26 AM on 8 July 2012
       Murry Salby's Correlation Conundrum
       @oarobin The mass balance argument is sufficient as it proves that natural emissions must be smaller than natural uptake, and hence the net action of the natural environment is opposing the rise in atmospheric CO2. "that is another possibility is that all Ea is taken up by the environment which also emits excess carbon equal to C'." There is no physical mechanism by which the natural environment could preferentially take up all of anthropogenic emissions. However, even if it could, in order to have conservation of mass natural emissions would still have to be less than natural uptake, in order for the observed rise to be less than anthropogenic emissions. Bart has frequently tried to dismiss the mass balance argument as being static rather than dynamic, however this simply isn't true. Figure 1 is the results of the mass balance argument, not that the net environmental sink has inter-annual variability and is gradually strengthening over time. One wonders how this is possible in a static analysis. Essentially introducing a time index variable is an attempt at obfuscation. The key result is that conservation of mass tells us that: En - Un = C' - Ea This is true for any time, i.e. En(t) - Un(t) = C'(t) - Ea(t) so if at any time the right hand side is negative, we know the left hand side is as well. You don't need a more complicated model, the only reason Bart intrduces it is to avoid discussion of the mass balance argument.
57094. Dikran Marsupial at 06:09 AM on 8 July 2012
       Simply Wrong: Jan-Erik Solheim on Hansen 1988
       @angusmac As IIRC I mentioned in an earlier post, it is unreasonable to specify any percentage as being a reasonable error range without an anlysis of the physics of the problem. In this case, even if the model physics were perfect and the model had inifinite spatial and temporal resolution, it would only be reasonable to expect the projection to be within the range of effects that can arise due to internal climate variability (a.k.a. weather noise, unforced response etc.). The best estimate we have of this is the spread of the model runs, if the observations fall within the spread of the model runs then the model is as accurate as it can claim to be. As I said, the spread of Hansen's model runs, had he the computational power at the time to have run them, is unlikely to be smaller than those of the current generation of models. At the end of the day, given the state of knowledge available at the time, Hansen's projections do a pretty good job. If you disagree, and want to perform a solid scientific/statistical evaluation of the model, then download the code, adjust for the differences in the estimated and observed forcings etc., and generate some model runs and see if the observations lie within the spread. As I said, rules of thumb are all very well, but they are no substitute for getting to grips with the physics.
57095. Bob Lacatena at 05:58 AM on 8 July 2012
       Climate change is simple: We do something or we’re screwed
       Chris G, In your analogy, there is a point, however gray and fuzzy it may be, at which the electric shock becomes unbearable, a point at which you would never, ever consider putting up with that much pain. That is the point Dave Roberts is talking about. That is what he means by "out of time." If we wait too much longer before taking action, the price and the suffering will be way, way beyond anything we would ever choose to endure.
57096. Chris G at 05:18 AM on 8 July 2012
       Climate change is simple: We do something or we’re screwed
       I have a slight objection to the phrasing of the problem as being out of time or not. As long as we don't hit a tipping point which would make any effort on our part moot, the damages are not binary, they are analog. Or, put another way, it is not like tossing a coin, you win or you lose; it is more like electric shock. A very little hurts a little, the more you apply, the more it hurts, and there is no real upper limit to the pain, until you are dead. It is never a bad idea to slow down the car even if you think you may crash anyway. I do not think that Dave Roberts says we are out of time. Out of time would imply that we are already committed to hitting a tipping point that would overwhelm anything we might try to do, and he specifically says that he doesn't think that is very likely, at present. An interesting talk. Not much new there, but he has reached most of the same conclusions I have, but then, we all have to watch out for our own confirmation biases.
57097. Stephen Baines at 03:55 AM on 8 July 2012
       Nil Illegitimi Carborundum
       Stephen Baines, USA
57098. Stephen Baines at 03:51 AM on 8 July 2012
       Roy's Risky Regression
       Exactamundo.
57099. Stephen Baines at 03:42 AM on 8 July 2012
       Murry Salby's Correlation Conundrum
       Oarabin Strictly speaking, I'm sure one could construct a mathematical budget that could reconcile a natural source with a CO2 increase less than human emissions. But to be relevant such a budget should be realistic from a biophysical and chemical point of view, and it must be consistent with data in hand on reservoir sizes, stable isotopes etc. To summarize then, for a natural source to be responsible for the recent CO2 increase 1) The anthropogenic CO2 to be taken up almost exclusively by natural sinks, while the natural CO2 remains in the atmosphere. I can think of no mechanism that could cause that to be true. 2) The source must be terrestrial (because surface acidification of the ocean indicates net uptake of atmsopheric CO2 while C isotopes and atmspheric oxygen trends are inconsistent with oceanic outgassing) 3) The net loss from this terrestrial source must amount to >40% of living terrestrial biomass (!!!) or >15% of soil organic carbon. It would have to be much larger as there should be some compensatory uptake by other reservoirs, and release from the mystery reservoir does not seem to be reaching some limit. 4) That source must look like very old plant carbon interms of isotopic composition. 5) Atmospheric oxygen must be consumed in rough proportion to release. That's a pretty hard list of requirements to satisfy, and I don't think you even can get past #1, which is why the budget approach has power. Then again, why look for an alternative explanation when we already have an explanation in hand that is consistent with everything we know about the carbon cycle?
57100. sol6966 at 02:54 AM on 8 July 2012
       Roy's Risky Regression
       Stephen Baines @ 16 Thanks. So a relative decrease in C14 = old and a relative increase in C12 = plant Therefore, if the rise were due to volcanoes then C14 would still decline but C12 would stay relatively constant. Sorry for dragging this off-topic

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