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Comments 93651 to 93700:

93651. Tom Curtis at 01:26 AM on 7 March 2011
       Icing the Medieval Warm Period
       DB @66, may I suggest you leave it up until WB posts his screenshot at his blog, then I can post a screen shot of your response at his blog.
93652. Tom Curtis at 01:24 AM on 7 March 2011
       Icing the Medieval Warm Period
       Gilles @65, yes, that is exactly what I would expect. New Zealand temperatures, after being flat for the first part of the 20th century started to rise in the 1930's. Glaciers do not care what causes the temperature to rise, they only respond to that rise. Further more, in 1930, the CO2 concentration was 306.6 (Law Dome), generating a total additionaly forcing in excess of 1750 levels of 0.54 w/m^2, or half that in 1980 (or a third that in 2000). For comparison, the net incease in solar forcing from its lowest point in the 19th century to its highest in the twentieth is just over 0.3 w/m^2. Once again, the claim that because global temperatures do not fall out of the confidence interval of natural forcings alone until after 1980, that therefore anthropogenic forcings are inconsequential before that is a fallacy, and shows the person making the claim does not know what a confidence interval is. In fact, it is transparently a fallacy because the models also show that: 1) The temperature does not fall outside the confidence interval of combined anthropogenic and natural forcings over the same period; 2) The combined anthropogenic and natural forcings predict a higher temperatures than natural forcings alone (thus shown the anthropogenic forcings to be significant); and 3) The temperature tends to lie near the center of the anthropogenic and natural forcings, but on the extreme limit of the confidence interval of natural forcings alone. The natural interpretation of that is that, on the evidence: 1) Both anthropogenic and natural forcings are significant in the early part of the 20th century; 2) Natural forcings have a 5% or less chance of explaining early twentieth century temperature alone; 3) Natural forcings have virtually no chance of explaining temperatures in the late twentieth century alone; 4) Anthropogenic forcings combined with natural forcings have a better than 66% chance of explaining temperatures across the whole twentieth century without involving any other factor; 5) There is a 33% chance or less that some other factor is involved, but it must explain only a small part of the variation; and 6) Anthropogenic forcings are dominant in the late 20th century. Once you accept these 6 facts, you will find you no longer need to distort science to accommodate your world view.
93653. RickG at 01:03 AM on 7 March 2011
       Blaming the Pacific Decadal Oscillation
       A Google Scholar search using the words "El Nino humidity" reveals a plethora of papers discussing the relationship.
93654. Alexandre at 00:07 AM on 7 March 2011
       A Real-World Example of Carbon Pricing Benefits Outweighing Costs
       Marcus #58 I'm interested about that algae biofuel price you mentioned. Do you have some reference or link?
93655. muoncounter at 00:06 AM on 7 March 2011
       Blaming the Pacific Decadal Oscillation
       RW1: "if a mere natural 'oscillation' can cause as much as a 0.5 C spike in global average temperatures in one year ... " Now you are making a major assumption with the contention that all of ENSO is an entirely natural oscillation. From Yeh et al 2009: Using calculations based on historical El Nin˜o indices, we find that projections of anthropogenic climate change are associated with an increased frequency of the CP-El Nin˜o compared to the EP-El Nin˜o. ... the occurrence ratio of CP-El Nin˜o/EP-El Nin˜o is projected to increase as much as five times under global warming. "why couldn't slower natural oscillations cause most of the 0.6 C warming in the 20th century? " Here you're assuming that such slow oscillations exist at all, let alone in sufficient amplitude to 'cause' any such change. Then you'd have to explain why 'slow' oscillations cause rapid temperature increase in a pattern that accelerates (increases in rate of change) towards the Arctic. It would be interesting indeed if you applied the same zeal that you've shown for testing forcing theory to Spencer's calculations referenced in the context of Figure 3 of this post. That would be the skeptical thing to do.
93656. Ken Lambert at 23:27 PM on 6 March 2011
       Climate Sensitivity: The Skeptic Endgame
       #96 BP So how does your analysis relate to the purported TOA warming imbalance currently about 0.9W/sq.m? Does it increase with projected levels of CO2 from a 'do nothing emissions scenario going forward? Or does it start to decrease from herein? What would be your suggestion of the surface temperature increase at equilibrium??
93657. Marcus at 22:40 PM on 6 March 2011
       A Real-World Example of Carbon Pricing Benefits Outweighing Costs
       Oh, to give you an inkling of why electric cars are better than conventional ones. An average electric car gets uses 15kw-h of electricity per 100km of travel (though most current models use closer to 10-12kw-h). In Australia, electricity currently costs $0.30c per kw-h. So an electric car here would cost about $4.50 per 100km of travel. By contrast, a petrol powered vehicle consumes about 9L of petrol per 100km of travel (assuming highway travel) & petrol currently costs about $1.30 per liter. So a conventional vehicle would cost about $11.70 per 100 km of travel. Not hard to see which is the cheaper alternative-especially as the price of oil continues to rise.
93658. Marcus at 22:34 PM on 6 March 2011
       A Real-World Example of Carbon Pricing Benefits Outweighing Costs
       "It's just more and more expensive, and the economy cannot afford a 100 ou 200 $ barrel without a strong recession. Replacing an expensive resource by another expensive resource is obviously hardly an "opportunity"." Man, there are so many things wrong with this comment I really don't know where to begin. Peak oil is *exactly* the reason why we shouldn't be wasting what oil we have left on inefficiently transporting people, 1 person to a car, using the most inefficient form of transportation currently available-cars propelled by internal combustion engines. If we're going to use conventional oil at all, it should *only* be in those parts of the economy where nothing else will suffice. In the rest of the transportation network, we should be looking at switching people to mass transit and/or vehicles that run on electricity-preferably supplied from renewable sources. Of course electric vehicles are currently far less expensive to run than petrol powered vehicles, due to lower maintenance costs & better "fuel" efficiency of the former. As to algal biomass derived bio-diesel-test bed facilities in the US have already proven that bio-diesel derived from algal biomass can be achieved at significantly lower cost than from conventional oil-with prices as low as $20 per barrel once commercial scale operations are achieved. Of course this is easy to believe when you consider that the oil is being produced from waste emissions-so are not costing any extra money, & that the energy required to extract & process the oil in algae is far, far less than that required to extract & refine conventional oil. So, yes, I do see a cap-&-trade system as an opportunity, given that it will provide us with the opportunity to *finally* make our transport network more efficient & less carbon-intensive.
93659. Gilles at 21:25 PM on 6 March 2011
       A Real-World Example of Carbon Pricing Benefits Outweighing Costs
       "You see, every so-called problem is really just an opportunity in disguise." Rob : I know, peak of conventional oil has probably already occurred - unconventional "all liquids" may still have a small margin for progression however. marcus : Peak oil is not due to the lack of oil, it is due to the lack of CHEAP oil. There is still plenty of oil underground. It's just more and more expensive, and the economy cannot afford a 100 ou 200 $ barrel without a strong recession. Replacing an expensive resource by another expensive resource is obviously hardly an "opportunity".
93660. Marcus at 20:50 PM on 6 March 2011
       A Real-World Example of Carbon Pricing Benefits Outweighing Costs
       "I'm sure most people are aware that oil is a necessary component of both food transport and industrialized farming methods (heavy machinery, artificial fertilizer production etc)." Well of course there is a fairly obvious solution. High Density Vertical growth chambers filled with algae can be used to sequester the CO2 & NO2 generated from the production of electricity from natural gas. This algae can then be used as both a source of bio-diesel & a natural fertilizer or high-protein feed for animals-thus the agricultural sector with carbon neutral versions of its key requirements-thus avoiding the need for higher food prices. Also, if farmers want to earn extra income under a cap-&-trade system, they can do so by (a) planting trees, (b) allowing some of their land to be set aside for Wind Turbines or PV panels & (c) using crop & animal waste to produce methane-methane that can be used to provide electricity & heat for towns & cities. You see, every so-called problem is really just an opportunity in disguise.
93661. Rob Painting at 20:02 PM on 6 March 2011
       A Real-World Example of Carbon Pricing Benefits Outweighing Costs
       Gilles - Note : FAO food index is much better correlated with the price of oil than with the average temperature of the world. I'm sure most people are aware that oil is a necessary component of both food transport and industrialized farming methods (heavy machinery, artificial fertilizer production etc). Of course there's going to be some correlation. if peak oil happens soon Done & dusted Gilles. It happened in either 2005 or 2006 (depending on which official estimate you choose). Peak oil refers to the peak rate of extraction, it doesn't refer to the price of oil.
93662. williambaskerville at 19:57 PM on 6 March 2011
       Icing the Medieval Warm Period
       @ Moderator [ - Complaining about moderation removed - ]
       Moderator Response: [Daniel Bailey] As it was pointed out to you previously, it is not ad hominem to show an argument as being silly, which was done in relation to your statements. Complaining about having to comply with the Comments Policy adds nothing to the dialogue here & thus begs for moderation. I will leave this up for a time so you have a chance to see it & will then remove it. No one wants to stifle dialogue that's on-topic and complies with the Comments Policy. Thanks!
93663. Paul D at 19:49 PM on 6 March 2011
       A Real-World Example of Carbon Pricing Benefits Outweighing Costs
       "Strikes me whatever the evidence CO2 emissions aren't stopping any time soon unless some miracle happens so all these discussions really are academic. Suspect it is probably prudent to start planning adaptation, with clear goals of carbon sequestration (this would a miracle or an enigma size effort), rapid transformation to a low energy use none fossil fuel society." You do both. Cut emissions and plan to adapt for current warming. In that respect the discussion is not academic. The fact that discussions focus on one aspect do not mean people and governments ignore the wider issues. The UK is put together adaptation plans as well as plans to cut emissions.
93664. Timothy Chase at 19:20 PM on 6 March 2011
       Blaming the Pacific Decadal Oscillation
       RW1 wrote in 28:

       "Temperatures after the '98 el Nino were the same as they were going in. No net heat increase. Oscillations have no input to the trend." Why not? Why doesn't the increase in temperatures set off the 'positive feedbacks' and make temperatures go higher and stay higher? If water vapor and cloud feedbacks, which operate on the order of days to weeks (or even hours), are positive as claimed by the AGW hypothesis, why did the temperatures come back down so quickly?

       Ok, you raise temperatures and this causes water to evaporate, and like the greenhouse gas that it is (as you can see here) it reduces the rate at which energy escapes the top of the atmosphere. Now what? The temperature isn't suddenly going to jump up to its Charney equilibrium. The warming due to greenhouse gases is the result of a net, small imbalance in rate at which energy in the form of radiation enters the system. Greenhouse gases -- such as water vapor -- will reduce the rate at which energy escapes to space, but the rise in temperature due to water vapor feedback would -- like the warming due to carbon dioxide -- take years. And likewise you won't have the full rise in water vapor from increased levels of carbon dioxide right away. Part of the increase in levels of water vapor in the atmosphere is a response to higher temperatures that are themselves the result of higher levels of water vapor. Unlike the spike in temperature that results from an El Nino, much of the carbon dioxide that we emit will remain in the atmosphere for years, decades and even millenia. Raise the temperature of an object and it will emit more radiation. The warm water of the El Nino emits thermal radiation a higher rate than cooler ocean water. But it doesn't reduce the rate at which energy leaves the system. Carbon dioxide does -- and it will continue to do so until the system warms up, increasing the rate at which radiation is emitted so that the system achieves equilibrium at a higher temperature. However, the equilibrium due to carbon dioxide alone is lower than the equilibrium of carbon dioxide plus water vapor. And if the system cools down due to the negative feedback where a warmer object emits more radiation, increasing the rate at which it cools (the Planck feedback) then this will bring temperatures down before temperature has the chance to rise significantly due to increased water vapor. When the temperature drops this reduces the humidity of saturation and the extra water vapor will fall out of the atmosphere in the form of precipitation. RW1 asked:

       Also, please explain how global temperature spikes coming down so quickly, such as those that occur during el Nino events, is inconsistent with net negative feedback operating on the climate system?

       It isn't. And you do have a negative feedback: Planck feedback. A hot object emits radiation proportional to the absolute temperature raised to the fourth power. That happens pretty much right away. Increased levels of carbon dioxide due to higher temperatures reducing the capacity of the ocean to hold carbon dioxide? That would take centuries. In the absence of a long-term forcing such as that due to the Milankovitch cycle or higher levels of carbon dioxide due to the emissions of some supervolcano Planck feedback wins. But once carbon dioxide is in the atmosphere much of it tends to stay there for a long time. Now you tell me: if you don't have the full water vapor, cloud or sea ice response to an increase in temperature until several decades after the imposition of a new forcing to the climate system, what does the rate at which at which the climate system cools off after an El Nino have to say about whether there is a net positive or negative feedback? Beyond the Planck feedback, whatever the feedback (water vapor, clouds or melting sea ice) it really hasn't had a chance to affect the system since such feedbacks result in only a small imbalance in radiation entering the system over radiation escaping the system and the heat content and temperature of the system will rise only gradually, significantly only if this imbalance is maintained.
93665. Timothy Chase at 19:03 PM on 6 March 2011
       Blaming the Pacific Decadal Oscillation
       Tom Curtis wrote in 30:

       As I understand it, global temperatures peak sometime after the peak of the El Nino or La Nina they are associated with. That lag shows the effect of the El Nino or La Nina is not just the effect of the change of Sea Surface Temperatures on the global average. There must be a feed back involved.

       The strength of the El Nino is measured by temperature in the tropics. However, just because the temperature in the tropics begins to drop precipitously doesn't mean that the water from the El Nino is losing all of its heat to the atmosphere. The warm water spreads out, circulating beyond the tropics, raising the temperature of the ocean beyond the tropics (which figures into the average global land and ocean temperature) and increasing the surface area that is exposed to the atmosphere, raising the temperature of the atmosphere over the ocean, and due to atmospheric circulation raising the temperature of the atmosphere over land as well. We really aren't talking feedback at this point. Somewhat higher levels of water vapor? Sure. But for the full feedback and effects of this to be felt from a new forcing that forcing must be maintained over a substantial period of time. And the full rise in the levels of water vapor will take essentially the same length of time.
93666. Gilles at 18:57 PM on 6 March 2011
       Icing the Medieval Warm Period
       Tom : "So, what I can find is not a trend downward that starts in 1998, but an overall 50% loss of NZ glacier mass balance starting in the early 1930's. Out of that massive decline, you were only able to find a few cherry picked upward slopes, the longest of which is less than 10 years long. " But this is NOT what you would expect, if this decrease were caused by the anthropic forcings that are supposed to exceed significantly the natural ones only after 1970 ? about flattening : what is certain is that there is no sign of significant acceleration since 1970. Do you have an idea of how much acceleration is needed before the warming becomes "dangerous" ?
       Moderator Response: [DB] Enabled inline graphic.
93667. Chief Hydrologist at 18:35 PM on 6 March 2011
       Blaming the Pacific Decadal Oscillation
       It should rather be the Interdecadal Pacific Oscillation -because it is a basin wide multidecadal phenomenon that acts through modulation of the intensity and frequency of ENSO. Cloud cover changes in the tropical and subtropical regions are most strongly influenced by sea surface temperature. SST is most strongly influenced by ENSO+PDO. Observational evidence shows cloud cover and optical depth decreasing following the great Pacific climate shift in 1976/1977 to the late 1990's and increasing thereafter (Burgmann et al 2008, Clements et al 2009, Norris 2005) - consistent with these multidecadal changes in SST. These changes are consistent with the trends of ERBS, ISCCP and HIRS radiative flux data showing a decreasing trend in reflected shortwave and an increase in emitted longwave from the mid 80's to the late 1990's. There seems to have been a decrease in Pacific cloud cover in the late 1970's and an increase in the late 1990's - which if you anywhere near accept the quantum of the satellite data dominated warming in the period. I do have a recent post here - http://judithcurry.com/2011/02/09/decadal-variability-of-clouds/
93668. Tom Curtis at 18:27 PM on 6 March 2011
       Blaming the Pacific Decadal Oscillation
       RW1 @33: "How do you figure a lag means there must be a feedback involved? Let alone positive feedback?" If it was not a feedback mechanism, the global temperature effects would exactly coincide with the temperature effects on the surface of the pacific ocean, and would equal the surface temperature effects on the tropical pacific divided by the area effected. As it happens, the maximum global temperature effect lags the maximum surface temperature effect in the Pacific, and is larger than the proportional change in SST. Because the global temperature response lags ENSO, the causal direction must be ENSO -> global temperature response, rather than the other way round. Hence, it is a feedback. "You're making an awfully lot of assumptions here. What causes the SST cooling and warming (i.e. what causes El Ninos and La Ninas?)?" No assumptions. The increase of globally averaged specific humidity with El Ninos (and decrease with La Ninas) is a well known phenomenon. The 1998 spike in humidity is as obvious as the spike in temperature. Further, the connection between high humidity and high temperatures is also well established by theory and observation. El Ninos and La Ninas are caused by variations in the strength of the Walker circulation, which are in turn driven by changes in the relative temperature between the Eastern and Western tropical pacific. So, the Walker circulation in effect acts as a feedback mechanism to that variation. What causes the initial variations is more dubious, with a number of factors implicated (and it is unlikely to be a single factor). "Again, you're making a HUGE number of assumptions here. How do you know that the response of EL Nino SO wouldn't be even stronger if were not for negative feedbacks opposing it? If you claim a +2 C over about one third of the planet caused a 0.5 C global average warming, how is that consistent with positive feedback? One third of 2 C is 0.67 C - more than the 0.5 C that occurred." Again, I know that it is a positive feedback because of the relative magnitude of the response. The maximum area affected by an El Nino is approximately one ninth of the Earth's surface. This excludes those parts of the Pacific that are cooled in an El Nino, which if included would weaken the calculated initial response (and hence strengthen the calculated feedback). The minimum area warmed is about 1/27th of the Earth's surface. It is difficult to estimate the total area warmed, but with very high confidence it lies between these two extremes. So, 2 degrees over one ninth of the Earth's surface, globally averaged is 0.22 degrees, much less than the 0.5 degree global increase. Hence the feedback must be positive. And that is the very conservative estimate, as it allows the maximum possible warming extent, and does not consider the cooling at other regions. Again the caveat, this is beer coaster mathematics, and only indicates ball parks. It is certainly accurate enough to show the sign of the feedback, but not accurate enough to narrow the magnitude significantly. None-the-less, the correlation does hold that the stronger the effect of ENSO on global temperatures, the stronger the positive feedback involved, and hence the stronger the positive feedback from CO2 induced warming. @ 34: Perhaps it will make it easier when you remember that a positive feedback enhances both warming from an initial warming, and cooling from an initial cooling. The return of Pacific SSTs to normal values after an El Nino is a cooling, of equal magnituded to the initial warming. It will therefore generate a cooling feedback of equal magnitude to the initial warming feedback, thus cancelling it out.
93669. Gilles at 18:16 PM on 6 March 2011
       A Real-World Example of Carbon Pricing Benefits Outweighing Costs
       yes but ... the fossil fuel prices will increase anyway, since unconventional resources can become profitable only with much higher prices. So there is a real paradox here : carbon tax is supposed to be efficient to avoid an increase of fossil fuel consumption, which could happen only if prices get higher ... much higher than any reasonably acceptable tax , actually. So why the natural increase of the resource price would not be enough? actually if peak oil happens soon, it seems that IT IS. Modern economy relies on cheap FF, and it may well be that it can simply not afford to high prices. Note : FAO food index is much better correlated with the price of oil than with the average temperature of the world.
93670. actually thoughtful at 17:39 PM on 6 March 2011
       A Real-World Example of Carbon Pricing Benefits Outweighing Costs
       The biggest failure of the anti Cap-and-Trade crowd is they assume that Americans will not respond to the increased price. So they assume Americans will just pay more for energy, instead of being motivated, by the increased savings in energy money, to reduce their costs. Indeed, the best way to motivate my fellow Americans is to explain they can avoid a "tax" by becoming more energy efficient. You will unleash the most powerful economic force in the history of civilization on earth: Americans desire to avoid taxes. The truth is there is some low lying fruit. A lot of of it. Inertia, and "cheap" fossil fuel keep that fruit rotting on the vine. Increase the marginal cost of fossil fuel, and people will be motivated to take action. The ACTUAL effect of increased energy prices is 1) more jobs and 2) people pay LESS for energy. This is somewhat counter-intuitive, but the trick to understanding it is to realize how much we can do. Look at your own home. Are windows R-5 or higher? Do you use the sun to heat your home and water? Do you use the sun or wind to create electricity? Are the walls insulated to R25 or higher and ceiling to R-40 or higher? Have you planted trees to shade the home in summer, and allow sunlight in during winter? Are all appliances Energy Star rated? Lightbulbs CFL or LED? All those energy conservation things pay for themselves in under 5 years. The active systems yield bigger paybacks, but also cost more and tend to take between 10 and 20 years to payoff (no subsidies). Active system life is 40+ years. After you factor in OPM (other people's money) the payback time is greatly reduced. You might think that OPM has its limits, but governments are well positioned to recognize the savings in things they pay for (healthcare, subsidized food, subsidized oil, wars for oil, etc.) and reward behavior changes in the energy sector and still be better off. This is yet another case where the narrative has been seized by people who can't or won't think things through beyond the very first move (a tax increases costs). If they thought about what happens in the 3rd iteration (lower costs to building owners, lower pollution=lower costs to government, higher employment) they would run out of rational objections. But that is not how policy makers think on this subject. We have master of tiddlywinks, when Chess or better thinkers are required.
93671. dana1981 at 17:30 PM on 6 March 2011
       A Real-World Example of Carbon Pricing Benefits Outweighing Costs
       Agnostic, the article says RGGI only applies to the power sector. Unfortunately it's not a very ambitious system.
93672. e at 17:29 PM on 6 March 2011
       Blaming the Pacific Decadal Oscillation
       RW1 > One third of 2 C is 0.67 C - more than the 0.5 C that occurred. He said "less than one ninth" not one third.
93673. RW1 at 17:24 PM on 6 March 2011
       Blaming the Pacific Decadal Oscillation
       Tom (RE: 32), "Assume an initial warming of the ocean has caused in increase in water vapour, and hence an enhanced greenhouse effect. The total amount of water vapour in the atmosphere will be the product of both the initial warming of the ocean, plus the feedback. If that initial warming is then removed by a change in the oscillation, the water vapour will now reduce to the amount appropriate for just the feedback warming. But that reduces the feedback, and hence the amount of water vapour, and so on. Consequently the temperature will relax back to the equilibrium state." I don't get it. I do understand that if an 'oscillation' causes an increase in temperature and then the 'oscillation' subsides or ceases, the temperature would decrease some, but I don't understand how with net positive feedback, why temperatures would decrease back to pre-oscillation - let alone decrease back so quickly. Furthermore, if a mere natural 'oscillation' can cause as much as a 0.5 C spike in global average temperatures in one year, why couldn't slower natural oscillations cause most of the 0.6 C warming in the 20th century?
93674. RW1 at 17:07 PM on 6 March 2011
       Blaming the Pacific Decadal Oscillation
       Tom (RE: 30), "As I understand it, global temperatures peak sometime after the peak of the El Nino or La Nina they are associated with. That lag shows the effect of the El Nino or La Nina is not just the effect of the change of Sea Surface Temperatures on the global average. There must be a feed back involved." How do you figure a lag means there must be a feedback involved? Let alone positive feedback? "However, El Ninos,ie, the condition with warm tropical Pacific SSTs is associated with warmer global temperatures. In contrast, La Ninas, with their cool SSTs, are associated with cool global temperatures. Therefore the feedback must be positive. The most likely cause would be increased water vapour during El Nino's driving increased heat by an enhanced greenhouse effect, and decreased water vapour during La Ninas having the opposite effect. The effect is short lived because the conditions that drive the feedback are short lived. After the SSTs return to normal, water vapour levels return to normal, and with it the the variation in the greenhouse effect. This picture is at least partly complicated by cloud albedo effects, with temperature variations in Australia in particular being driven by cloud albedo rather than water vapour feedback. You're making an awfully lot of assumptions here. What causes the SST cooling and warming (i.e. what causes El Ninos and La Ninas?)? "Denier's should be very worried about this pattern. IN 1997 an average 2 degree anomaly over less than one ninth of the Earth's surface caused a 0.5 degree excursion in the Global Mean Temperature. An equivalent excursion to a forcing causing a 1.2 degree increase in global temperatures (ie, a doubling of CO2) would cause a global temperature increase of between 2.7 and 8.1 degrees C. That is a very rough calculation of climate sensitivity, but it shows that appealing to El Ninos should give deniers no cause for comfort. The stronger the climate response to the EL Nino Southern Oscillation, the stronger the climate response to CO2 forcing." Again, you're making a HUGE number of assumptions here. How do you know that the response of EL Nino SO wouldn't be even stronger if were not for negative feedbacks opposing it? If you claim a +2 C over about one third of the planet caused a 0.5 C global average warming, how is that consistent with positive feedback? One third of 2 C is 0.67 C - more than the 0.5 C that occurred.
93675. Tom Curtis at 17:03 PM on 6 March 2011
       Blaming the Pacific Decadal Oscillation
       RW1: "If the feedback is positive in response to temperature increases, why doesn't that keep temperatures higher?" Assume an initial warming of the ocean has caused in increase in water vapour, and hence an enhanced greenhouse effect. The total amount of water vapour in the atmosphere will be the product of both the initial warming of the ocean, plus the feedback. If that initial warming is then removed by a change in the oscillation, the water vapour will now reduce to the amount appropriate for just the feedback warming. But that reduces the feedback, and hence the amount of water vapour, and so on. Consequently the temperature will relax back to the equilibrium state. The equilibrium state is determined by the balance of energy coming in by radiation from the sun, and the energy going out by IR radiation (along with energy flows between regions for regional temperatures).
93676. RW1 at 16:45 PM on 6 March 2011
       Blaming the Pacific Decadal Oscillation
       Bibliovermis (RE: 29), "The oscillations do not add energy to the system, but merely move it around. This is why global feedback effects are not relevant." How do you figure? And how do you know that 'the oscillations', such as el Ninos, are not the result of energy being added to the system? The point is temperatures do spike and clouds and water vapor operate in response to temperature changes - do they not? If the feedback is positive in response to temperature increases, why doesn't that keep temperatures higher?
93677. Tom Curtis at 16:39 PM on 6 March 2011
       Blaming the Pacific Decadal Oscillation
       RW1: As I understand it, global temperatures peak sometime after the peak of the El Nino or La Nina they are associated with. That lag shows the effect of the El Nino or La Nina is not just the effect of the change of Sea Surface Temperatures on the global average. There must be a feed back involved. However, El Ninos,ie, the condition with warm tropical Pacific SSTs is associated with warmer global temperatures. In contrast, La Ninas, with their cool SSTs, are associated with cool global temperatures. Therefore the feedback must be positive. The most likely cause would be increased water vapour during El Nino's driving increased heat by an enhanced greenhouse effect, and decreased water vapour during La Ninas having the opposite effect. The effect is short lived because the conditions that drive the feedback are short lived. After the SSTs return to normal, water vapour levels return to normal, and with it the the variation in the greenhouse effect. This picture is at least partly complicated by cloud albedo effects, with temperature variations in Australia in particular being driven by cloud albedo rather than water vapour feedback. Denier's should be very worried about this pattern. IN 1997 an average 2 degree anomaly over less than one ninth of the Earth's surface caused a 0.5 degree excursion in the Global Mean Temperature. An equivalent excursion to a forcing causing a 1.2 degree increase in global temperatures (ie, a doubling of CO2) would cause a global temperature increase of between 2.7 and 8.1 degrees C. That is a very rough calculation of climate sensitivity, but it shows that appealing to El Ninos should give deniers no cause for comfort. The stronger the climate response to the EL Nino Southern Oscillation, the stronger the climate response to CO2 forcing.
93678. Bibliovermis at 16:22 PM on 6 March 2011
       Blaming the Pacific Decadal Oscillation
       RW1, The oscillations do not add energy to the system, but merely move it around. This is why global feedback effects are not relevant.
93679. RW1 at 15:48 PM on 6 March 2011
       Blaming the Pacific Decadal Oscillation
       muoncounter (RE: 22) "Temperatures after the '98 el Nino were the same as they were going in. No net heat increase. Oscillations have no input to the trend." Why not? Why doesn't the increase in temperatures set off the 'positive feedbacks' and make temperatures go higher and stay higher? If water vapor and cloud feedbacks, which operate on the order of days to weeks (or even hours), are positive as claimed by the AGW hypothesis, why did the temperatures come back down so quickly? Also, please explain how global temperature spikes coming down so quickly, such as those that occur during el Nino events, is inconsistent with net negative feedback operating on the climate system?
93680. Riduna at 15:48 PM on 6 March 2011
       A Real-World Example of Carbon Pricing Benefits Outweighing Costs
       Alexandre @ 4 In some ways, a carbon tax (CT) may be preferable to cap and trade (ETS) but a CT is less cost efficient and effective in reducing CO2 emissions, which is the primary purpose of pricing carbon. 1. With a CT, the price of carbon is set by government (bureaucrats) rather than by the market. Why is market pricing more important? Because as the level of CO2 reduction increases and becomes more difficult to achieve, the carbon price fluctuates and increases. This continuing change in the price of carbon is best determined by an informed market than by government. 2. By itself, a CT does no more than “encourage” CO2 emitters and energy users to reduce emissions, except a desire to avoid paying a CT. There is no “compulsion” for them to do so, nor is government required to set a reduction target and act to achieve that target. An ETS is just the opposite. It does require government to publicly state annual and longer term emission reduction targets and it does require emitters to reduce their emissions or bear the cost of purchasing market-priced emission licenses to cover any shortfall in meeting the annual target. 3. An ETS gives certainty that CO2 emissions will be reduced, by how much, how fast and over what period - and it forces government and emitters to plan and set targets With a CT there is no such certainty, indeed the only certainty is the level of tax – and even that can be changed by a new government. 4. A CT can be made just as opaque as a poorly designed ETS scheme by being selectively applied, by paying off-setting subsidies to emitters, allowing tax rebates and other discriminatory practices. Some of these measures are applied with ingenuity and it was their proposed use which contributed to the defeat of Australian government proposals to price carbon in 2009/10. 5. Finally, is a Carbon Tax really a tax given that it is only levied on and paid by those directly responsible for CO2 emissions? It is not paid by any others earning a taxable income, though its effects in terms of higher energy bills may be paid by everyone. However, those least able to afford higher bills can be (and usually are) assisted by government. Perhaps a Carbon Tax would more accurately be described as a Carbon Levy or an Emissions Fee?
93681. Riduna at 15:41 PM on 6 March 2011
       A Real-World Example of Carbon Pricing Benefits Outweighing Costs
       Dana: Thanks for an interesting article. However, it is difficult to determine how successful it has been in its primary purpose – reducing CO2 emissions – since the article does not tell us what emitters are subject to the RGGI. Does it include all industrial emitters and transport? Is RGGI applied uniformly by all participants? Which, if any direct CO2 emitters are excluded from the scheme? What adverse effects has the cap and trade scheme had and how have these been dealt with? Without this info, it is difficult to evaluate its success in terms of its effects on energy bills, employment and other effects on the economy, particularly any movement of businesses out of participating states (carbon leakage), which is not reported on. What is clear is that CO2 emissions are being reduced, revenue is being earned and applied to employment in new businesses, notably those which increase the efficiency with which energy is used by consumers. It should come as no surprise that cap and trade has been introduced by RGGI participants without bringing about the economic damage which critics of pricing carbon so loudly warn us of – usually without substantiating their claims. For the last 6 years, the European Union has shown that introduction of properly designed and administered mechanisms for pricing carbon does reduce CO2 emissions without damaging their economies. There is of course a difference between introduction of cap and trade in a state of the Union and in a country, such as Australia, Canada or the USA as a whole. Countries may find it necessary to include in the design of a cap and trade scheme, introduction of a “carbon tariff”, to protect domestic industry from unfair competition of imports produced in countries which do not effectively abate CO2 emissions. Although European countries have not felt a need to introduce a carbon tariff (yet), my prediction is that it will be introduced by those countries which are effectively reducing CO2 emissions as a protective measure against countries which are not. Such a tariff has the added benefit of persuading errant countries to curb their CO2 emissions, while protecting complying countries from carbon leakage.
93682. johnd at 15:33 PM on 6 March 2011
       Blaming the Pacific Decadal Oscillation
       Riccardo at 00:36 AM, frequency would only be irrelevant if the situation you originally described was the case, that being "Whatever the impact of one phase might be, the opposite phase would have the opposite effect and after a full cycle the system would be brought back to where it was at the beginning.", however that would be to assume opposite phases to be mirror images of each other. The PDO, or any other such ocean atmosphere systems are based around geographic distribution of warmer and cooler SST's, and the difference between each phase is the relative location of the warmer waters versus the cooler waters. In addition there is also the relative location to adjoining land masses. In addition, within each phase there is also a "front" and a "back" where the system also manifests itself in different ways. Perhaps the easiest way to illustrate this is to consider that what El-Nino means to those on the eastern rim of the Pacific is what La-Nina means to those on the western rim. What then has to be also taken into account is that the surface of the planet is an irregular surface, with a very uneven distribution of land masses, and different ocean conditions, meaning that when the systems change phase, the physical environment also alters which then influences how the system interacts with the local and adjoining regions, thus determining how it ultimately manifests itself, and how that then controls the liberation or conservation of heat as it transfers between the ocean and the atmosphere, which then feeds into whether the ocean is gaining or losing heat in that particular location, during that particular phase. If identical circumstances were in play at either side of each phase, then perhaps I could see how things may balance out. But I suspect that they are not, and if that means things do not return to balance as each cycle completes, then a changing frequency becomes relevant.
93683. KR at 15:22 PM on 6 March 2011
       Blaming the Pacific Decadal Oscillation
       TIS - Keep in mind, "It's just a jump to the left, then a step to the right". Oscillations don't add energy; they just move it around. The PDO is a redistribution, not an added amount of total energy such as we see in global warming.
93684. jyyh at 14:52 PM on 6 March 2011
       Blaming the Pacific Decadal Oscillation
       An odd thought, while it's clear PDO (or AMO for that matter) cannot explain GW, could it relate to the speed of arctic amplification? This claim would base itself to the Bering strait flows, which at least in the summer are going mostly north for the warmer waters of the Pacific. Years back I thought that this PDO thing was somehow cleverly modified derivative of the overall GW signal, but looks like there is something else too, at least on regional (well continental) level. But still, if there's no predictive model there's not much use to an index.
93685. Marcus at 14:01 PM on 6 March 2011
       Blaming the Pacific Decadal Oscillation
       Yes, Muon & Timothy, the point I meant was that the various ocean oscillations move heat energy around-both from one part of the ocean to another, & also between the ocean & the surrounding atmosphere-& vice versa. The point is that this heat energy isn't being created out of nothing-its heat energy that has already been added from another source. As an example, the 1998 El Nino was simply releasing a large amount of stored heat from the oceans into the atmosphere-probably accumulated over the previous decade or two-it didn't *create* that heat. Hope that makes more sense.
93686. Timothy Chase at 13:52 PM on 6 March 2011
       Blaming the Pacific Decadal Oscillation
       The Inconvenient Skeptic wrote:

       In the 1998 event the average global temperature increased by more than 0.5C. That energy was not simply moved around the surface of the Earth. The La Nina did not create the energy, but it added energy to the surface and the atmosphere that wasn't at the surface before. So these events do add (or take) energy to the system.

       If one's idea of "the climate system" is limited to the first couple of meters of the atmosphere and the first few centimeters of ocean, then yes, of course these events can add energy to "the system." However I doubt that this is what Marcus was thinking of when he posted his comment. By "climate system" I would assume he meant at least the first ten kilometers of atmosphere and more importantly the ocean that extends well below those first 10 centimeters where the temperature of the ocean is usually measured. On average the ocean goes down to a depth of over 2.6 miles and at its deepest 6.85 miles -- and unless you've found a wormhole its a pretty safe bet that the only way the ocean is going to heat up is if the rate at which energy is entering the climate system through the top of the atmosphere is greater than the rate at which energy is leaving the climate system through the top of the atmosphere. This is called "radiation balance theory" since the only way energy is going to enter or leave is as radiation. It is a cornerstone of climate science. But in terms of the balance of energy you can think of it as the principle of conservation of energy -- which Marcus alluded to when he said that climate oscillations cannot create energy -- they can only move it about. We know of course that other than the ups and downs of the solar cycle solar irradiance has been flat to falling since at least 1962. So it doesn't look like what explains the net increase of energy in the system lies with the rate at which energy is entering the system. So we have to look at the other side of the equation: the rate at which energy leaves the system. And we have a pretty good idea of what is happening there. Now if you are a regular here you have undoubtedly run into the essay Did global warming stop in 1998? (intermediate) which shows that more than 20X as much of the excess heat that has entered the climate system has gone into the ocean. Sometimes some of that heat comes back to the surface -- but as Marcus points out the climate oscillation didn't create that heat. The temperature of the ocean is increasing, including the deep ocean. And in fact the ocean is where the vast majority of the heating is taking place. If you just look at the surface or the atmosphere you are harboring a rather superficial view of the climate system. If so, you should probably venture a little further away from land some time.
93687. muoncounter at 13:51 PM on 6 March 2011
       A Real-World Example of Carbon Pricing Benefits Outweighing Costs
       Blessthefall, "what good is it doing when China and India's emissions continue to rise?" US emissions are still 4x China and 10x India on a per capita basis. We have short memories. Fifty years ago the western US had terrible air pollution problems; thirty years ago it was eastern block Europe's Black Triangle. Both have cleaned up through tough emissions standards. If China et al admit that their Brown Clouds are a problem they can get started cleaning up, it will make the US even more unpopular.
93688. muoncounter at 13:25 PM on 6 March 2011
       Blaming the Pacific Decadal Oscillation
       TIS "La Nina did not create the energy, but it added energy to the surface and the atmosphere that wasn't at the surface before. So these events do add (or take) energy to the system." That's just plainly untrue, as even a Spencer graph shows: Temperatures after the '98 el Nino were the same as they were going in. No net heat increase. Oscillations have no input to the trend.
93689. The Inconvenient Skeptic at 12:50 PM on 6 March 2011
       Blaming the Pacific Decadal Oscillation
       Marcus, Consider a strong La Nina event. The atmosphere starts neutral and the ocean starts to warm. As the SST increases and the area affected also increases the atmosphere starts to warm from convective and latent heat transfers. In the 1998 event the average global temperature increased by more than 0.5C. That energy was not simply moved around the surface of the Earth. The La Nina did not create the energy, but it added energy to the surface and the atmosphere that wasn't at the surface before. So these events do add (or take) energy to the system. I will also add that MacDonald's study was a tree-ring study that used results during a mega-drought. I would much rather trust a corral reconstruction for something like SST's.
93690. Marcus at 11:59 AM on 6 March 2011
       Blaming the Pacific Decadal Oscillation
       As far as I understand it, the point here is that the PDO-like the NAO & the AO-cannot actually *create* energy within the system-all they do is move that energy around. If that is the case, then the PDO can't really be a *cause* of warming-it must surely be responding to another source of energy entering the system.
93691. Marcus at 11:49 AM on 6 March 2011
       A Real-World Example of Carbon Pricing Benefits Outweighing Costs
       @BTF. If you will keep repeating the same fallacies-in multiple threads-over & over again, like an obstinate 5-year old, then that's exactly how I'm going to speak to you. That said, I didn't speak to you that way when I tried-very calmly-to explain why your claims are fallacious. You keep telling us that Coal, Oil & Nuclear are "cheap & efficient", yet at the end of the day all 3 energy sources consume a relatively expensive, non-renewable resource in a extremely thermally inefficient manner in order to generate energy. Given that the fuel sources also involve expensive & highly destructive extraction techniques-not to mention the extremely toxic by-products that their consumption generates-it becomes easy to see how your claims of "cheapness & efficiency" simply don't stack up. If they are so "efficient", then why is the majority of the fuel consumed without producing anything useful? (The most efficient Coal power stations only convert 35% of the energy released from the coal into electricity-the rest being lost as waste heat. The most efficient Nuclear Power stations (highly experimental gas-cooled varieties) only convert 50 % of the energy released into usable electricity. The most efficient Internal Combustion Engines only convert 20% of the energy released from petrol into forward momentum-the rest being lost as waste heat). If they're so cheap, then why do all 3 industries still demand massive subsidies from tax-payers-60-150 years after the technologies were first introduced? Modern Renewable Energy technologies have been around for as little as 30 years yet-with only a small fraction of the Government Support enjoyed by your "cheap & efficient" technologies-they've managed to achieve massive strides in efficiency, reliability & cost per kw-h. Now its true that some Oil companies might publicly promote a "belief" in AGW, or support for renewable energy technologies-but this is purely for PR purposes. Behind the scenes, the oil & coal industries are the biggest financial backers of those organizations most vociferously promoting "skepticism" about both AGW & the usefulness of renewable energy & energy efficiency measures-because whatever they might say publicly, they'll all do whatever it takes to protect their massive profit margins.
93692. Tom Curtis at 11:02 AM on 6 March 2011
       A Real-World Example of Carbon Pricing Benefits Outweighing Costs
       ranyl @43, the increased price of oil is driven primarily the increased demand from India, and especially China. The increased prices will put a dent in that demand, but won't eliminate the factors that are driving it. However, if you think that it does not effect car purchases, consider this graph:
93693. Rob Honeycutt at 10:59 AM on 6 March 2011
       A Real-World Example of Carbon Pricing Benefits Outweighing Costs
       Blessthefall @ 38 said... "Rob, I don't see how one country reducing emissions will do anything if the rest of the world goes unchecked. It doesn't make any sense. Some say it's a "good place to start," but what good is it doing when China and India's emissions continue to rise?" I know this was for another Rob, but you might take note that China is putting huge amounts of money into renewable sources. Vastly more than we are. They want to develop those technologies so that they can sell them to us. We need to be doing the same in order to sell them the technologies they need. That's what we're good at but we're rapidly slipping in that area. Look, this is all a no-brainer. In coming decades the entire world will be involved in pricing carbon. Pricing it enables us to develop technologies for the future. By avoiding this we are risking our future standing as the leader of the modern economic world.
93694. Tom Curtis at 10:38 AM on 6 March 2011
       Icing the Medieval Warm Period
       Williambaskerville @59, to answer my question of the prior post - evidently not. Trust you when shown the overall temperature trend once the influences of the solar cycle and ENSO to show the raw figures, and cherry pick the bit between the largest El Nino on record and a near record La Nina and talk about flattening.
93695. Tom Curtis at 10:32 AM on 6 March 2011
       Icing the Medieval Warm Period
       williambaskerville, you may well like to look up the definition of "ad hominen". My comments indicated that a certain argument was silly, not that a particular person was. I also indicated that a particular activity was foolish. It is not ad hominen to say it is foolish to bang your head against the wall, even in the presence of somebody who is doing it. It is of course open to anybody to judge the foolishness or wisdom of that man if, after you have reminded them how foolish their activity is, they do not stop. Now on to your head banging ... The chart may only start in 1977, but you already have the comment of scaddenp @30 that the glacier's are in long term retreat. Also the comment of nigelj @45 (after your cherry picking post, but before your futile attempt to defend it) that, "Over the last 100 years the trend is most glaciers are retreating, or a nett decrease in ice mass. From NIWAS website." And, of course, and most crucially, you had from NIWA at the link provided with the graph where you foolishly cherry picked the upward trends, the comment that, " NIWA’s snowline surveys show an overall decrease in the glacier mass balance", and that:

       2. Despite the sensitivity of New Zealand glaciers to changes in both precipitation and temperature, the volume of ice in the Southern Alps dropped by roughly 50% during the last century. New Zealand’s temperature increased by about 1 °C over the same period. I would also point out that as you are trying to find an equivalent case to that studied by Koch & Clague, you needed a case in which there was wide spread regional glacier growth over the course of the century (such as they found in the MWP), and should yourself have checked whether NZ's glacier growth was century long, or just a few years or decades. Had you done so, you would have found out about the overall retreat of NZ glaciers: So, what I can find is not a trend downward that starts in 1998, but an overall 50% loss of NZ glacier mass balance starting in the early 1930's. Out of that massive decline, you were only able to find a few cherry picked upward slopes, the longest of which is less than 10 years long. Do you think it might be wise to stop banging your head yet?

93696. adelady at 10:24 AM on 6 March 2011
       A Real-World Example of Carbon Pricing Benefits Outweighing Costs
       ranyl@43 "But as oil prices have jumped since 2006, and fossil fuel use hardly blinked an eye...." Oil and total fossil fuel are not the same thing. Oil use is mainly related to transport and to rising living standards allowing more people to use cars rather than other transport. Fossil fuel used for power generation rises with increases in industrial activity and, with luck, associated improvements in domestic living standards. The balance of these factors is pretty well settled for advanced economies. But in developing economies, the increases in power generation precede the improvements in living standards (at least those that involve more use of oil based fuels.)
93697. Rob Honeycutt at 10:15 AM on 6 March 2011
       Blaming the Pacific Decadal Oscillation
       dana1981 at 13, responding to thingadonta #3: "these 3 coupled periods (sun+-PDO) correspond better than c02 does in the 20th century...implying that climate sensitivity to c02 is low." Dana: "Sorry no, you don't calculate climate sensitivity by looking at correlations." That was my thought as well, Dana. "CO2 alone" is one of the more firmly agreed upon figures for climate sensitivity at 1C.
93698. ranyl at 10:04 AM on 6 March 2011
       A Real-World Example of Carbon Pricing Benefits Outweighing Costs
       "ranyl @3, while a carbon price will not significantly reduce demand for energy, to which we are adicted, it will significantly change the best means of sourcing that energy. The only way this is not true is if alternative power sources are so inefficient as to by not commercially viable at any reasonable price (contrary to the claims of their advocates)." Hi Tom, But as oil prices have jumped since 2006, and fossil fuel use hardly blinked an eye, what evidence is there that a higher price unless much higher will make any difference to use really? Strikes me whatever the evidence CO2 emissions aren't stopping any time soon unless some miracle happens so all these discussions really are academic. Suspect it is probably prudent to start planning adaptation, with clear goals of carbon sequestration (this would a miracle or an enigma size effort), rapid transformation to a low energy use none fossil fuel society. Not sure renewables are the all saving grace, wind farms do heat and dry the land as well several other things, solar panels are associated with tri-nitro_floride release and rare metal mining, large dams casue huge CO2 releases from ecological effects and so on. Not using energy is in a real challenge but surely not worth taking the risk of CO2 levels over 400ppm for?
93699. Timothy Chase at 09:34 AM on 6 March 2011
       Blaming the Pacific Decadal Oscillation
       Bob Tisdale wrote:

       The difference in the multdecadal variability of ENSO (NINO3.4 SST anomalies as a proxy) and the PDO should be a function of North Pacific Sea Level Pressure...

       It's not eye balling as they use statistics, but you might be interested in Di Lorenzo et al. (2010 ) ENSO and the North Pacific Gyre Oscillation: an integrated view of Pacific decadal dynamics (presented at AGU 2010 Ocean Sciences Meeting) nevertheless.
93700. Bob Tisdale at 08:55 AM on 6 March 2011
       Blaming the Pacific Decadal Oscillation
       Timothy Chase: The difference in the multdecadal variability of ENSO (NINO3.4 SST anomalies as a proxy) and the PDO should be a function of North Pacific Sea Level Pressure, with the SLP altering the strength of the gyre spin-up into the KOE.

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