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Berényi Péter at 19:36 PM on 8 April 2010Oceans are cooling
#23 contd. Looks like volumetric thermal coefficient of seawater also depends on pressure and (to a lesser extent)salinity. It is 2.44 × 10-4 K-1 at 0 °C, 108 Pa (bottom of abyss). Pressure dependence may close the gap. IES 80 (UNESCO International Equation of State of Seawater 1980) Algorithms for computation of fundamental properties of seawater by Fofonoff & Millard, 1983 Sea Water Equation of State Calculator, Johns Hopkins University, Applied Physics Laboratory, Ocean Remote Sensing Group However, there is still room for improvement -
Jacob Bock Axelsen at 19:22 PM on 8 April 2010Are we too stupid?
Commenters in this thread have discussed the problem of population growth. In that respect it might interest the audience that many economists are coming to the sobering realization that the era of continous economic growth is probably soon coming to an end: Degrowth Conference Barcelona 2010. -
Jacob Bock Axelsen at 19:05 PM on 8 April 2010Are we too stupid?
embb The point is, you need the same young generation applying the same peer pressure in China. Do you see that happening? No, because of censorship of the media. I was mostly thinking of societies where public opinion and public policy making is correlated. I do not think indirect reciprocity is the holy grail. However, something new is called for and tests show that it works specifically for this huge public goods game. -
JMurphy at 19:04 PM on 8 April 2010Ocean acidification: Global warming's evil twin
JRuss wrote : During the global cooling from 2004 to 2009, our oceans did absorb more CO2 resulting in a decrease in pH. Do you have any figures or references for that global cooling in association with that decrease in pH ? How significant are the trends and the relationship between the two ? -
embb at 18:53 PM on 8 April 2010Are we too stupid?
Jacob: "The reason indirect reciprocity has not been applied yet is because these results are rather recent. With social networking media for an entire young generation in place, perhaps social peer pressure could be much stronger than for us." The point is, you need the same young generation applying the same peer pressure in China. Do you see that happening? -
embb at 18:45 PM on 8 April 2010Are we too stupid?
Gallopingcamel: it is even nicer - there is a real possibility of using thorium as a nuclear fuel, and there is plenty of it. -
fydijkstra at 18:44 PM on 8 April 2010Is the science settled?
Riccardo (99): Do Santer et al say the opposite of what I claim? This is their closing remark: “We may never completely reconcile the divergent observational estimates of temperature changes in the tropical troposphere. We lack the unimpeachable observational records necessary for this task. The large structural uncertainties in observations hamper our ability to determine how well models simulate the tropospheric temperature changes that actually occurred over the satellite era. A truly definitive answer to this question may be difficult to obtain. Nevertheless, if structural uncertainties in observations and models are fully accounted for, a partial resolution of the long-standing ‘differential warming’ problem has now been achieved. The lessons learned from studying this problem can and should be applied towards the improvement of existing climate monitoring systems, so that future model evaluation studies are less sensitive to observational ambiguity.” Translated into normal language: ‘Sorry, we could not find the hot spot, that was predicted by the models. Our data are too ambiguous. Maybe in the future, we will have better observations to test our models.” On the other hand, Santer et al show, that Douglass’ claim is wrong, that he proved that the hot spot does not exist. Douglass has not yet got the opportunity to contradict this. These together show my point: that the science on this issue is not settled. Chris (105) “…Since paleoanalysis indicates that the warming of the last 30 years is exceptional at least in the context of the last millennium and likely last two millennia…”: We all know, that this claim is highly controversial. The use of carefully selected high quality treering data for the reconstruction of the temperature in the past two millennia is very tricky. There is no need to figure that out in this posting. Craig Loehle has shown, on the basis of non-treering proxies, that the present warm period is not exceptional (Energy & Environment 18(2007), 1049-1053). But the IPCC-figure 1 in Box 6.4 (AR4, page 468) does not justify this claim either, given the fact, that the post-1960 data have been replaced by thermometer measurements (the famous ‘divergence’ problem). My point was, that the science on this issue is not settled, and that remains true. Chris (105): “…ocean current contributions to 20th century warming indicates that these have made close to zero net contribution to warming over the last 100 years…” OK, you have a point. There is a clear correlation between the ups and downs of the ocean currents and the global temperature and the net effect of this multidecadal oscillation is about zero. The oscillation is superposed on a slow rise in temperature by 0.5 degrees per century, that the earth experiences since 1800. Whether that warming is related to CO2 is not settled. The warming in the last 30 years was probably the up going phase of the oscillation. You may know the clear analysis of Akasofu of these cycles (http://people.iarc.uaf.edu/~sakasofu/pdf/two_natural_components_recent_climate_change.pdf). My point is not that Akasofu tells the ultimate story, but only, that the science on this issue is not settled. So, to return to John’s question: does less understanding on one issue invalidate better understanding on other issues? Of course not. But the most important issue has not been settled: will cutting our CO2-emmissions have any effect on the global climate? We don’t know. -
embb at 18:42 PM on 8 April 2010Are we too stupid?
There is a ugly practical side to this question - when it comes to a mutually binding agreement it has to be seen as "fair". Now, emerging industrial nations like China or Brasil will definitely use the non-sensical argument that the "West" caused the problem so fair means that they should get a bigger share of the commons. This argument can also be used to reject any kind of emission control, and where does that leave us? -
Tom Dayton at 14:50 PM on 8 April 2010A database of peer-reviewed papers on climate change
There is a good case study of the process of writing, submitting, revising, and publishing a scientific article in a peer-reviewed journal, recounted on RealClimate's post Science Story: The Making of a Sea Level Study. Also there is an inline response by one of the authors of that journal article, Stefan: "I've certainly had more papers rejected than accepted by Nature and Science." (The inline response is to comment #8 by Andy S on 6 April). Stefan's professional and grateful attitude differs starkly from McKitrick's attitude. -
Doug Bostrom at 13:53 PM on 8 April 2010Climate's changed before
Rogerthesurf, you'd do better to explain yourself. Failing that, presumably you won't care if your post is deleted? -
Doug Bostrom at 13:49 PM on 8 April 2010Humans are too insignificant to affect global climate
jmymac1958, we're going to be forced to make a radical change in the amount of fossil C02 we liberate into the atmosphere not so far down the road, not necessarily because we actually care about the climate but because fossil fuels are a but a blip on our history, here today and gone tomorrow. Now-- while we still have "free" power available from fossil fuels-- is the time to figure out what our long term energy supply will be. We've got a limited amount of resources and time to sort out what our more permanent and reliable energy sources will be. Assuming we don't succumb to some sort of disaster, this era of fossil fuel usage we're living in right now will seem to our descendants as quaint and outmoded as do chipped flints to our own modern day chefs. Imagining that C02 is the only challenge we're facing w/regard to fossil fuels misses many future chapters of our story. -
gallopingcamel at 13:31 PM on 8 April 2010Are we too stupid?
My last posts on this thread (#42 & 43) caused quite a reaction. While I don't like to disappoint my fans, I have some new courses that start next week so I have some preparation to do. One has to stay at least a week ahead of the students! My regard for this blog and its denizens remains undiminished so I plan to return when the pressure of work eases. I don't want my last post to be disagreeable so I will refrain from offering any opinions. All I ask is that you view a video. This is not an unreasonable request as many of you ask me to read material that you consider important. Here is the link: http://www.youtube.com/watch?v=AHs2Ugxo7-8 This video covers the science relating to the availability of fission fuels; the effects of mining activities on the environment; "burning" high level nuclear waste; reactor safety issues; reducing plutonium production; truck mounted reactors and much more. I see "4th generation" nukes as something that both sides of the AGW debate could support. Am I wasting my time and yours? -
Rogerthesurf at 12:52 PM on 8 April 2010Climate's changed before
"What does past climate change tell us about global warming?" In case you dont know it, your explanation uses the AGW theory to explain the question when the question is really asking for some proof of the AGW theory. Cheers Roger http://www.rogerfromnewzealand.wordpress.com -
Bern at 12:07 PM on 8 April 2010Ocean acidification: Global warming's evil twin
From Peru at #17: Both. Actually, not just frozen then fried, but fried then frozen then fried, as I understand it (no citations, so take it with a grain a salt). I believe one consequence of a large impact is an enormous amount of debris which spreads out over most of the planet, much of which is very hot (incandescant?) when it hits the ground, causing very widespread fires. There's your first fry-up. Of course, this also releases a *lot* of CO2 & aerosols. The aerosols (from the impact & subsequent burning) then have an enormous negative radiative forcing, causing the big freeze. As these aerosols settle out, though, over a relatively short period of time, the forcing from the massive GHG pulse becomes dominant, and the temperature heads north again. On the one hand, this GHG contribution would tend to prevent an impact from causing a snowball earth. On the other hand, such drastic climatic swings would almost certainly lead to mass extinctions. Sorry I don't have any references - this is just pulled from memory, but I'd love to read a paper examining climatic consequences of large impacts, if anyone knows of one (or more). -
jmymac1958 at 12:06 PM on 8 April 2010Humans are too insignificant to affect global climate
I'm not a scientist, so maybe I didn't get my point across: It's not possible for us to make a radical enough change to the amount of CO2 humans are putting into the atmosphere to make a difference. We'll have to live with it.Response: The question of whether it's possible to reduce our CO2 sufficiently has been examined in the peer-reviewed literature (Pacala 2004). The verdict:Humanity already possesses the fundamental scientific, technical, and industrial know-how to solve the carbon and climate problem for the next half-century. A portfolio of technologies now exists to meet the world's energy needs over the next 50 years and limit atmospheric CO2 to a trajectory that avoids a doubling of the preindustrial concentration. Every element in this portfolio has passed beyond the laboratory bench and demonstration project; many are already implemented somewhere at full industrial scale.
To borrow from the Bionic Man, "we have the technology!" -
jmymac1958 at 12:02 PM on 8 April 2010Humans are too insignificant to affect global climate
PS: This is the best web site I've seen for rational debate. I haven't read one post where someone is called ....ing idiot or ....redneck. Very cool. -
jmymac1958 at 11:47 AM on 8 April 2010Humans are too insignificant to affect global climate
A Drop in a Bucket Volume of the Earth’s Atmosphere: How thick is the atmosphere? There are many different answers to this question. Everyone agrees that the atmosphere consists of 5 layers. The bottom layer, the troposphere, contains 75% of the gas. The thickness of this layer, depending on who you ask, varies between 8 km and 15km above the surface of the earth. For the purposes of this discussion, I’ll use the lower limit of 8 km. Also, for this discussion, I won’t consider the remaining 4 layers of the atmosphere, as there is very little gas in these layers. Volume of a sphere: The radius of the earth is 6,360 km This makes the radius of the earth plus the troposphere to be 6368 km (6,360 + 8). The formula for finding the volume a sphere is: 4/3 X π X r3. To determine the volume of the troposphere: (1) Plug in the larger number (radius of the earth plus the troposphere) (2) subtract the volume of the earth: (4/3) X (3.142) X (6,368km)3 = (4/3) X (3.142) X (258,231,468,032 km3) = 1,081,817,696,742. km3 For the earth: (4/3) X (3.142) X (6,360km)3 = (4/3) X (3.142) X (257,259,456,000 km3) = 1,077,745,614,336 km3 Subtract the volume of the earth from the volume of the volume of the earth plus the troposphere: 1,081,817,696,742 km3 – 1,077,745,614,336 km3 = 4,072,082,406 km3 = the volume of the troposphere For this discussion, I’m going to use 4.07 billion cubic kilometers as the volume of the troposphere. US Gasoline Use in 1 Year The U.S. Energy Information Administration says the United States uses 378 million gallons of gasoline, per day, for motor consumption. (378,000,000 x 365) = 137,970,000,000 gal/year For this discussion, I’m going to use 138 billion as the number of gallons of gasoline, for motor consumption (cars), burned in the U.S. in a single year. CO2 Emissions The International Carbon Bank and Exchange states that burning a gallon of gasoline produces 4.867m³ of CO2. Multiplying the 138 billion gallons of gasoline burned in the U.S. by the 4.867 m3: (138,000,000,000 x 4.867 m3) = 671,646,000,000 m3 There are 671.6 trillion cubic meters of CO2 produced by gasoline motors in the U.S. in one year. This is equal to 671.646 cubic kilometers. To give this unit a name, I’m calling it an ALGIT (Al Gore’s Inconvenient Truth). One algit = 671.646 cubic kilometers = the volume of CO2 gas produced by all the gasoline motors in the US in one year. Percentage of the Atmosphere If the volume of the atmosphere is 4.07 billion km3, and an Algit is 671.646 km3, then the atmosphere contains (4.07 billion / 671.646) algits. This equals 6,059,739.80 algits. The CO2 produced by the U.S. (from gasoline burning motors), in a single year is equal to .0000165% of the atmosphere. Drops in a Bucket One drop of water is a minum. Twenty minums make a milliliter. If we consider a one gallon bucket, there are 3,785.4 milliliters in a gallon, so there are 75,708 minums (drops) in a bucket. The number of Algits in the atmosphere is 6,062,039, so there are 80 times (6,059,739.8 / 75,708) as many algits in the atmosphere as there are drops in bucket. Another way of looking at this is that it would take 80 years for all the gasoline motors in the U.S. to produce the amount of CO2 that would be the equivalent of a drop in a bucket. So if we stopped using all gasoline motors in the U.S. today (impossibility), each year would have the effect of 1/80th of a drop in the bucket of the atmosphere. Doesn’t seem worth it. The earth is warming up - let's spend our efforts (and $) figuring out what to do as it gets warmer. Buying electric cars and crappy lightbulbs won't do it.Response: Another way of looking at it, and I would argue the most appropriate way to look at it, is how much heat is this trace amount of CO2 trapping? This has been accurately determined by line-by-line calculations and confirmed by direct measurements by satellites and surface measurements. Observations in the real world confirm the increased greenhouse effect from more atmospheric CO2.
But I agree, buying electric cars and more efficient lightbulbs are only a tiny drop, to borrow your metaphor, compared to the effort required to lower and eventually stop CO2 emissions. -
Steve L at 10:48 AM on 8 April 2010Ocean acidification: Global warming's evil twin
I find the level of analogy between the skeptic arguments regarding ocean acidification and those already debunked regarding climate to be remarkable. Er, perhaps the are homologous. Anyway, in comment #4, which I otherwise thought was a waste of time, the sixth point about buffer systems not being very well understood was worth adding to. Being a fish guy, I like this story, and so will you: "Fish an 'ally' against climate change." I haven't read enough papers on this topic yet, but I like the fourth one on Ari's CC Observer page Wooten et al (2008) pdf, particularly figures 1B and 2B. These show that things are already changing. A friend in the scallop farming industry tells me that there's been trouble with low pH so far this year. I can't help but think that the observed reduction in pH on the coast of the Pacific Northwest is too fast to be due directly to anthropogenic CO2 emissions (though those certainly can't help). I think I read somewhere or heard that changing wind patterns are bringing more ancient CO2 into surface waters than used to occur. Anyway, the changes in coastal invertebrate communities (like those shown in the Wooten et al paper) at this early stage are probably a bit of a window into the kinds of changes we'll be seeing in the open ocean in the next few decades. -
P@J at 10:12 AM on 8 April 2010Ocean acidification: Global warming's evil twin
"Dinosaurs died frozen or cooked?" Does it really matter? The climate changed faster than the plants could adapt to the change, so the dinosaurs starved. -
Chris McGrath at 09:37 AM on 8 April 2010Ocean acidification: Global warming's evil twin
An important point, often overlooked, is the use of CO2-only figures in papers such as Pelejero et al (2010). However, most policy-makers use the term "carbon dioxide equivalents", rather than CO2-only targets, when discussing stabilisation targets for climate change. For example, targets for stabilizing temperature rises between 450-550 ppm "carbon dioxide equivalents" generally include all components of the atmosphere affecting global temperature rises, including CO2, other greenhouse gases and the cooling effects of aerosols. For further discussion, see: http://www.climateshifts.org/?p=683 John, this could be the subject of a useful post from you clarifying the differences between CO2-only and CO2-equivalents targets. -
VoxRat at 09:24 AM on 8 April 2010Ocean acidification: Global warming's evil twin
JRuss, #18: "in the deep oceans there are lakes of almost pure CO2." I think you're mistaken. Do you have a reference for this? -
Berényi Péter at 09:13 AM on 8 April 2010Oceans are cooling
BTW, even the Levitus OHC history reconstruction gives only a 0.14 °C increase in temperature for the upper 700 m of oceans for the entire 53 year period between 1955 and 2008. It is a problem indeed. Same author says average thermosteric sea level rise for this period was 0.39 mm/year. For a 700 m deep water column to expand by 20.7 mm in response to 0.14 °C warming, volumetric thermal expansion coefficient should be 2.1 × 10-4. It can only happen if average temperature of the upper 700 m is more than 20 °C. Now. In fact average temperature of ocean surface waters is 17 °C and this is the warmest layer. Below the thermocline (100-200 m on average) it gets really cold fast. At 700 m it can not be more than 5-6 °C. Therefore average temperature for the upper 700 m is somewhere around 10 °C. At this temperature volumetric expansion coefficient of water is only 0.88 × 10-4. It means that either OHC increased twice as much as Levitus claims or steric sea level rise was half of his value. There is of course a third, most unlikely possibility: temperature of seawater might have increased only in the warmest parts and layers of the ocean and nowhere else. -
Doug Bostrom at 07:56 AM on 8 April 2010Ocean acidification: Global warming's evil twin
JRuss, can you supply a pointer showing where we may read about naturally occurring pools of liquid C02 in the deep ocean? -
Jacob Bock Axelsen at 07:52 AM on 8 April 2010Are we too stupid?
Alexandre I assume you mean some kind of voluntary action that would lead to the agents "preferring" to stay within the rules (even if informal rules)(...) I don´t see this happening in large scale (nation, world). The problem, of course, is that on the other hand coercion for nations could mean war. Lovelock actually mentions this in his interview. And you are right about the problem of air pollution. In fact, handling particle filters on diesel cars has turned out to be hard to control even with laws. The setup in Milinski's first game is that the collected funds will be used to publish a notice in the newspaper about the study. The more funds the bigger the notice. Admitted, a poor substitute for the cost of investing in sustainable energy sources, but it gets interesting because it makes the players cooperate much more when using indirect reciprocity and/or informing them. The reason indirect reciprocity has not been applied yet is because these results are rather recent. With social networking media for an entire young generation in place, perhaps social peer pressure could be much stronger than for us. I have already read newspaper stories about the difference in culture of young people e.g. being upset about leaving appliances on stand by, using less water, sorting trash etc. The children will naturally be better educated than our contrarian generation, so enlightenment is implied. -
Berényi Péter at 07:45 AM on 8 April 2010Oceans are cooling
#21 Ned at 03:33 AM on 8 April, 2010 All that said, I think Doug Bostrom has the most important point here There are things I am as good at as an expert. Energy conservation is one of them. Here are the OHC anomaly data for each quarter between 1955 & 2009 according to the NODC Ocean Climate Laboratory: 1. quarter 2. quarter 3. quarter 4. quarter The error bars supplied are way too small if you take into account the differences between various reconstructions, but that's another story. According to the ISCCP-FD Radiative Fluxes database the 85-89 based Total Net Global Mean Anomaly at TOA is about -3 W/m2, basically flat between 2002 and 2005 with a rapid (sub-annual) oscillation. We do not know the correct offset, so the zero level is arbitrary, but there was no any climatically relevant change detected in this period. There might have been instrumental problems in 2000-2001, none later. Now. NODC OHC anomaly annual averages for 2002-2005 look like this: 2002 7.095 ± 0.527 × 1022 J 2003 10.481 ± 0.535 × 1022 J 2004 12.154 ± 0.494 × 1022 J 2005 11.247 ± 0.445 × 1022 J That is, from 2002 to 2003 OHC increased by 3.386± 0.751 × 1022 J and it has decreased by 0.907 ± 0.665 × 1022 J between 2004 and 2005. The difference is 4.293 ± 1 × 1022 J. It means that Earth has accumulated that much more heat in 2002-2003 than in 2004-2005. As Earth surface area is 5.1 × 1014 m2, the difference in net radiation balance is 8.42 ± 1.96 × 107 J/m2. A year is 3.16 × 107 sec. Therefore the difference in net radiation flux should have been 2.66 ± 0.62 W/m2. That is, from 2002-2003 to 2004-2005 Total Net Global Mean Anomaly at TOA should have decreased by at least 2 W/m2. It would be very visible in the ISCCP-FD graph, but in fact nothing like that can be seen. The extra heat needed to increase OHC in 2002-2003 could come from nowhere else than from TOA radiation anomaly, since there is no component in the climate system other than the oceans capable to store and supply that much energy. But it could not come from above. Therefore the NODC reconstruction is flawed. Q.E.D. -
Riccardo at 07:29 AM on 8 April 2010Ocean acidification: Global warming's evil twin
I found some common misconceptions over the internet and here in the comments. The first, and the least important, is the use of the word acidification. Doug already clarified the meaning and its use; but neverthless, it's obviously irrelevant. Call it de-alkalinization or pH change, it doesn't matter, what's important is the effect. Some people think that CO2 in water forms HCO3- plus H+, the former then decomposes into CO3-- plus H+ and then increasing CO2 will increase CO3--. If true, it would favour the formation of calcium carbonate. Unfortunately, the opposite is true. The buffering effect to CO2 induced pH reduction consists in limiting the H+ concentration increase by formation of more HCO3- at the expenses of CO3--. Calcification is then limited not by availability of Ca++ but by CO3-- concentration, which is declining along with pH. pH has the same fate as CO2 in the sense that skeptics claim, for example, that it's not true that pH reduction influences corals growth, the latter being related to temperature. Did anyone ever say that corals growth is governed just by pH? Corals, as well as other shell forming organisms, respond (among other things) to temperature, true; but a reduced pH will increase their stress and limit the resilience to increasing temperature. Other human induced stresses (pollution) come also into play and clearly more stress means less resilience. Similarly, no one ever said that all species are getting into trouble, at least not in the short run. For example, some organisms (e.g. foraminifera) form calcite while others (e.g. corals) aragonite structures. The latter is more soluble than the former, so it is expected that aragonite forming organisms will be more vulnerable to pH reductions. And this is not the whole story. Some organisms, for example, are able to use different chemical paths to form their shells making them much more resilient to water acidification. The last myth that comes to my mind is that you need to have an acidic water (pH<7) to have any impact on calcium carbonate dissolution. This is not true, any alteration of a chemical equilibrium brings the reaction one way or another. -
JRuss at 07:22 AM on 8 April 2010Ocean acidification: Global warming's evil twin
The solubility of carbon dioxide in water varies greatly with temperature and pressure. At the surface of the ocean, [760 mm Hg] the solubility in grams of CO2 in 100 g (pure water)is .3346 @ 0 C, .2318 @ 10 C, .1688 @ 20 C, .1257 @ 30 C, etc. Global warming warms the ocean surface causing release of CO2. Global cooling allows the ocean to absorb CO2 as the ocean cools. But in the deep oceans there are lakes of almost pure CO2. Presumably, much of this is from under sea volcanoes where the pressure is high enough for CO2 to liquefy, and being denser the water, fall to the ocean floor. Slowly, this CO2 does migrate to the ocean surface. During the global cooling from 2004 to 2009, our oceans did absorb more CO2 resulting in a decrease in pH. Now that our globe is again warming, I expect the oceans to release vast quantities of CO2 and thus increase the pH of the ocean's surface. During of period of global warming, the amount of oceanic release of CO2 can be greater then all from all the power plants and vehicles man has made. -
From Peru at 06:52 AM on 8 April 2010Ocean acidification: Global warming's evil twin
So the K-T impact caused cooling or warming? Or to be more explicit, what happened , a "Nuclear Winter" or a "Greenhouse Oven"? Dinosaurs died frozen or cooked? -
Marcel Bökstedt at 06:02 AM on 8 April 2010Southern sea ice is increasing
I’m not convinced that this problem is well understood yet. My feeling is that it is dangerous to use data from the sea off Antarctica as evidence either for or against AGW, until there is a consistent model covering the whole area. Unfortunately, it might not be so easy to provide one. I’ve been trying to read the literature, and intend to give my dumbed down version of it below, in the hope that someone with more expertise can correct me. OBSERVATIONS: Much of this depends on the “reanalysis” project, that tries to reconstruct climate data for the period 1957-96. It seems clear from Boning el al that there is a measured warming trend of the water of the Southern Ocean (between 30 and 60 degrees south, down to 2000 meters). The reanalysis of temperature records seem (Zhang) to show that in the interval 1979-2004 the air surface temperature in the much smaller “ice covered area” around Antarctica has been rising. There is also a measured increase in Antarctic sea ice extent (Turner et al and references therein) In addition to this there is also a further measured change, related to the Antarctic Oscillation (also called Southern Annular Mode). There are two modes (Thompson & Solomon): High index means cold polar temperatures, strong western winds, and low index means the opposite. This index has been rising, increasing winds and decreasing polar temperature. There is evidence that this development is driven by the “ozone hole”. All of the above seem to comparatively safe. In particular the simplistic argument “more ice means the South Polar Sea is colder” is nonsense, we do know that the Polar Sea is getting warmer, so that the extent of ice on the Ocean is definitely a bad proxy for temperature, But when it comes to explanations of what we see, things look a lot more murky to me. Two main players seem to be the layering of the Southern Ocean water (less dense water above denser water) and the constant western winds around 60 degree. THE EKMAN SPIRAL: The wind possibly contributes to the mixing of layers in an interesting way: the wind drives an ocean current which runs around the Antarctic moving from West to East. This current extends down into the ocean, with the surface water moving fastest, and deeper water moving in the same direction, but slower, Because of the Coriolis effect, the current will try to veer to the left, which means towards the North. Now, since the surface water moves faster than the deeper water, the net effect is stronger at the surface, So surface water will move to the North, which forces deep water to the south. This creates a down-welling North of the current, and an upwelling South of the current. This whole business is called an Ekman spiral. BONING: The paper by Boning et al. quotes measurements that seem to show that even if the circumpolar winds have been increasing, that “Ekman spiral” has not become stronger. They believe that the reason for this is that the increased wind also produces more eddies, which confuse the whole picture. They note the the models that has been used cannot resolve those eddies (they are too small). If they are right, the lack of enhanced mixing of layers in the ocean is not yet theoretically understood. ZHANG: Zhang’s paper is a pure model study The main point of the article is that he can construct a model of the South Sea that agrees with two important seemingly contradictory measured factS: it has a warming ocean, but an increase in sea ice. I think that the mechanism proposed by Zhang is slightly (but not essentially) different from what John describes. The motor driving various changes is the increase in surface temperature. This initially leads to a decrease in production of new sea ice. The top water gets warmer and less salty. Both these changes work in the same direction, they both make the top layer less dense. The next thing that happens is that since the top layer is gets dense, there is less upwelling of warm water. This means that less ice is melted. So now, both less ice is created and less ice is melted. The model says that the change in melting is bigger than the change in the creation of new ice, so the net effect is that we get less ice. But wait? If less ice melts in the top layer, the salinity will increase, counteracting the previous effect? Zhang says that this is so, but we still have to take the warming of the top layer into account! This warming makes the top layer lighter, decreasing mixing of layers. So now there are lots of things going on: Since the top water gets warmer, less ice is produced. On the other hand, less ice is melted by upwelling deeper warm water. Then there is precipitation, but Zhang does not believe that the increase in precipitation is the decisive effect. And the sum of the three effects "creating less new ice", “destroying less old ice" and "warming the water" is actually that the top layer gets less dense - driving the cycle. This all seems a bit subtle for my taste, taking the big uncertainties into account. For instance, what happened to Boning’s eddies, which were supposed to be important? But at least this is a testable model. TURNER: This paper seems to ignore questions of up and down convection in the oceans, the questions that dominated Boning et al. and Zhang.et al. Instead it focuses on the strengthening of the western wind – the high index of the Antarctic oscillation. Another important point of this paper is that they break down the increase in sea ice into geographical areas and seasons. In particular, the ice in the Ross sea (close to the pole) has been increasing, while the ice in the Bellinghausen-Amundsen sea (father from the pole) has been decreasing. This is clearly important, and the regional differences should be explained. There is some modeling going on, but the upshot seems to be unclear (they conclude that it could all be natural variability). The paper is often cited for explaining increased sea ice by the polynyas in the Ross sea. It seems to me that they only suggest this mechanism, but they don’t give strong arguments for it. Possibly I’m missing something. -
Alexandre at 05:17 AM on 8 April 2010Are we too stupid?
Jacob #56 Axelrod shows that a cluster of cooperating individuals can displace the defectors and persist against mutations, making tit-for-tat evolutionary stable. In other words, the fisherman could try to convince a small group to put trust in him. I´ll try to find the time to have a look at Axelrod´s paper. Ostrom´s research finds something different: even though she detects that impulse of autruistically staying within the rules, when you don´t have means to enforce the rule, in her lab experiments and field research, this usually collapses as free riders appear more and more. Of course, some means to "enforce the rules" can be some informal, cultural behaviour like diminishing one´s reputation or maybe some physical harassment. This has been observed in small fisher communities, for example. But I don´t see this working in some nationwide scale, let alone worldwide. BTW, in environmental issues I have never seen any successful case of solving air pollution without proper legislation. This is the coercion option Hardin finally resorts to in his paper. Not having the results of Axelrod and followers he still faces the problem of how to agree on the necessary reform. Coercion is a necessary part of any law. The most successful stories involve the users themselves working out an agreement (even if they resort to the state´s coercive power to enforce it). To reach the agreement can be difficult, but it´s a necessary step. You see any alternative? This is why Milinski's results are so interesting: it can be handled using indirect reciprocity alone. I assume you mean some kind of voluntary action that would lead to the agents "preferring" to stay within the rules (even if informal rules). I don´t see this happening in large scale (nation, world). And I don´t know any success stories with something as diffuse as air pollution. Think of car gas emissions - that´s only within a city, and I´ve never seen a city controlling this kind of pollution with indirect reciprocitiy alone. -
Ned at 05:09 AM on 8 April 2010Ocean acidification: Global warming's evil twin
RSVP writes: "there are other examples of mass-extinctions coinciding with global warming and increases in atmospheric carbon dioxide" If I am not mistaken, in previous posts, arguments have been made against anthropogenic global warming as being faster than historically warmer periods produced solely by nature. Here is a switch that simply proves mankind is just as much a part of nature as anything else. You're right. In the 4.5 billion year history of the Earth, there have been six or more brief episodes of extreme climate change that each killed off a large fraction of life on the planet. If you use that as your yardstick, then our impact on the planet is not unprecedented in magnitude. I'm not sure what the policy relevance of this is, however. Does the fact that AGW won't be worse than a comet slamming into Yucatan mean that we shouldn't bother trying to prevent or reduce the impact of AGW? That's setting a pretty high bar for action, IMHO. -
Tom Dayton at 03:42 AM on 8 April 2010A database of peer-reviewed papers on climate change
Following up on Dennis's comment, compare E&E's web site to the clear and complete information for authors on the web site of the journal Science. -
Dennis at 03:35 AM on 8 April 2010A database of peer-reviewed papers on climate change
Poptech @29: You wrote: "E&E does use a real peer-review process as I have stated multiple times." You've stated that, but haven't provided any evidence beyond writing E&E "follows the standard academic review process." Can you direct us to evidence for that? I have found nothing of value from the E&E website -- no policy statement, no links to a parent organization's policy, nor the names of scientific peers who oversee the process. -
Ned at 03:33 AM on 8 April 2010Oceans are cooling
All that said, I think Doug Bostrom has the most important point here: Without doing more work, neither of us can be believed. The problem is, neither of us really knows what we're talking about here, not with the degree of expertise needed to sort out the instrumentation problem you believe you see. Fortunately, we amateurs are not the last word on this matter, instead we've got actual scientists working on the case. I concur entirely with this. -
Ned at 03:28 AM on 8 April 2010Oceans are cooling
BP writes: Anyway. Even by eyeballing (and disregarding lack of significance) the trend between 1959-2001 is 0.2 × 1022 J/year perhaps. It translates to a 0.12 W/m2 net "forcing" at TOA on average during this 42 years long interval. This seems a bit low. I get 0.26 W/m2 at the ocean surface, not 0.12 TOA, and TOA should be *higher* because of the albedo. Trend +2.4E21 J/year OHC700 (Ishii) or +3.2 (Levitus) or +4.1 (Domingues), from Levitus 2009 Conversion to watts 7.6E13 (Ishii) or 1.0E14 (Levitus) or 1.3E14 (Domingues) Area of oceans 3.61E14 m2 Trend at surface, not TOA +0.21 W/m2 (Ishii) or 0.28 W/m2 (Levitus) or 0.36 (Domingues) For comparison, NASA GISS has a table of annual net radiative forcings here. If you take the 1969-2003 forcings, multiply them by the area of the ocean and convert to J/year, the average over that time period is 1.0E22 J/year. So the OHC700 trend from those three papers is anywhere from 24% to 41% of what GISS suggests it should be. That's a bit low, even assuming some of the heat is going into the ocean below 700m. I'm going to have to read and think more about this; I may be forgetting something. For comparison, Domingues shows the following figure comparing their results to model predictions, including those of GISS:
That seems to show their observations falling nicely in the middle of the ensemble of models, which is hard to reconcile with a trend that's only 24% to 41% of what would be predicted from forcings. Unfortunately at the moment Nature's website seems to be down so I'll have to go back and reread Domingues later to see how they explain this.
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John Cross at 03:19 AM on 8 April 2010Ocean acidification: Global warming's evil twin
GFW: Part of your answer is that during ice ages, carbon is sequestered in the land in the form of dead vegetation. As the ice then recedes the vegetation can decay and CO2 is released. Regards, John -
Riccardo at 02:49 AM on 8 April 2010Oceans are cooling
I agree with Berényi Péter, it's a travesty that we can not track the energy flow through the climate system ... More details in the well known Trenberth's paper. -
GFW at 02:36 AM on 8 April 2010Ocean acidification: Global warming's evil twin
Ah, at least part of the answer to my question at 13 is likely to be related to the answer to johnd's questions at 11 regarding the definition of "surface". -
GFW at 02:33 AM on 8 April 2010Ocean acidification: Global warming's evil twin
Figure 1 suggests that dissolved CO2 in the ocean is historically in near equilibrium with atmospheric CO2. That makes sense given the rather large contact area. But it raises a huge question for me, one that must have been answered somewhere but I've so far not stumbled on it. What is the actual form of the carbon sink that interchanges with the atmosphere to form the Milankovitch-driven glacial cycle? My understanding is that in the slow cooling phase of the cycle, carbon is sequestered at the bottom of the ocean via the "rain" of dead organisms. If that understanding is correct, how does that reverse during the (relatively fast) warming phase of the cycle? -
Doug Bostrom at 02:27 AM on 8 April 2010Ocean acidification: Global warming's evil twin
RSVP, there's a fundamental difference between us and much of the rest of nature. Unlike a large rock following a deterministic Newtonian existence leading to an orbital rendezvous with Earth, we're not mindless, we have some iota of influence on our destiny. We've sprung from nature, but for better or worse we've transcended a limitation shared by most other features of the natural world and have got a least a few levers of control in our hands. We're not supposed to be "dumb as a rock"; to be mindless is no longer in our nature. -
Doug Bostrom at 02:13 AM on 8 April 2010Oceans are cooling
Berényi Péter, you do need to supply a hypothesis better than simply being suspicious of what could be a coincidental string of increases in observed OHC over 3 years. That's not really a workable hypothesis at all, not without elaboration. Assuming your notion about instrumentation changes is valid, I think you're missing a potential explanation for the "anomalous jump" you see, namely that adding instrumentation improved our ability to measure OHC. If I buy into the idea that 3 years of increasing OHC is down to instrumentation issues, I can as easily say the increase is due to better perception as you may say it's an error introduced by instrumentation changes. Without doing more work, neither of us can be believed. The problem is, neither of us really knows what we're talking about here, not with the degree of expertise needed to sort out the instrumentation problem you believe you see. Fortunately, we amateurs are not the last word on this matter, instead we've got actual scientists working on the case. After all of our handwaving is finished, they're still the horse's mouth with regard to this issue. -
johnd at 02:13 AM on 8 April 2010Ocean acidification: Global warming's evil twin
When the term "surface water" is used in relation to the oceans, it is generally used to identify a specific zone within the ocean. However it seems in this thread that the terms Ocean pH and surface water pH are both being used and interchanged, even in the OP graph. When surface water pH is mentioned, what depth of water is it referring to? When Ocean pH is mentioned does this refer to the full depth of the entire ocean or just different terminology that actually means surface water pH? For clarity perhaps it needs to be defined what each refers to, especially when pH values are being mentioned. -
RSVP at 01:59 AM on 8 April 2010Ocean acidification: Global warming's evil twin
"there are other examples of mass-extinctions coinciding with global warming and increases in atmospheric carbon dioxide" If I am not mistaken, in previous posts, arguments have been made against anthropogenic global warming as being faster than historically warmer periods produced solely by nature. Here is a switch that simply proves mankind is just as much a part of nature as anything else.Response: The one example of time-frames used above is the PETM which occured over a time-frame of thousands of years. This is substantially slower (at least an order of magnitude) than current warming. It's not just the amount of CO2 that we're emitting that is the problem with global warming - the rate is also important because climate is changing faster than nature is able to adapt. So while there have been other past periods where climate changed faster than nature could adapt, current conditions are even worse.
The primary lesson when looking at past climate change is that it gives us insights into how the planet responds to changes such as more atmospheric CO2 and/or disturbances in energy balance. And what we learn is that the planet is highly sensitive to changes in energy imbalance and that extinction rates increase when the climate change is more rapid. -
Berényi Péter at 01:32 AM on 8 April 2010Oceans are cooling
#15 doug_bostrom at 04:47 AM on 7 April, 2010 why should we arbitrarily decide a particular year's increase is an error simply because it's the largest difference on the graph? I have explained it above. The energy needed to create such a jump is missing. you should supply a hypothesis to explain how one year's error can influence subsequent derivations of OHC? No, I do not have to. But I have already supplied one anyway. Instrumentation and coverage changed a lot between fourth quarter 2002 & third quarter 2003.
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John Cross at 01:25 AM on 8 April 2010Ocean acidification: Global warming's evil twin
I was going to comment on what acidification means, but Doug did that. Then I was going to post about averaging large numbers but Tom did that. All I can do is to back up Tom's point with a link to Taminos. John -
Tom Dayton at 01:21 AM on 8 April 2010Ocean acidification: Global warming's evil twin
fydijkstra wrote "3. The oceans have a huge buffering capacity." Of course. But actual measurements reveal that the buffering is insufficient, because the pH has changed despite that buffering. That's not speculation, it is measurement. You wrote "5. A shift of the pH from 8.3 to 8.1 is not serious for most organism." Your statement is too vague to be useful, or even meaningful. If you actually read the actual scientific papers you will see highly specific descriptions of exactly what the consequences are expected to be, not just for individual species directly affected by such pH changes, but also for other species affected by the cascading effects such as disruption of the food chain. -
Tom Dayton at 01:10 AM on 8 April 2010Ocean acidification: Global warming's evil twin
fydijkstra wrote"2. Just as a global temperature, 'the' global ocean pH does not exist. We have only calculations of the average of various separate measurements. The accuracy of such an average can be estimated at 0.15 pH-units. This means, that the pH shift that is found now, is only slightly more than the error in the measurement. Statisticians have an expression for such a difference: ‘not significant’."
Of course both "global temperature" and "global ocean pH" are expressed as averages. Your misinterpretation of the standard uses of those terms is just as pointless and distracting as your misinterpretation of the term "acidification," as Doug pointed out. Regarding the "accuracy" of the average pH measurement: Randomly distributed errors in the individual measurements cancel each other, increasing confidence in the average measurement as the number of measurements increases. Read about the Law of Large Numbers. Statistical significance is not calculated as simply as you described. -
Berényi Péter at 01:03 AM on 8 April 2010Oceans are cooling
#15 Ned at 05:04 AM on 7 April, 2010 What strikes me about this figure is how close the agreement is among the three different teams By the year 2004 the difference between Leviticus vs. Ishii & Kimoto is more than 6 × 1022 J. Of course you can call this agreement close, provided the meaning of this word is redefined. In fact the discrepancy between them is so large, that huge error bars are needed to make them consistent. With those error bars I would be surprised to find a trend different from zero at any reasonable level of significance. It would be nice to have all the data in digital format and perform such a test.
Anyway. Even by eyeballing (and disregarding lack of significance) the trend between 1959-2001 is 0.2 × 1022 J/year perhaps. It translates to a 0.12 W/m2 net "forcing" at TOA on average during this 42 years long interval.
On the other hand according to the Mauna Loa record, CO2 has increased from 315.98 ppmv to 371.07 ppmv. If we accept the estimated sensitivity of 3.7 W/m2 for carbon dioxide doubling given in IPCC AR4 WGI 2.3.1 as a reference point, it should mean a 0.86 W/m2 increase in "forcing" by the year 2001 relative to 1959.
Log CO2 being almost linear, average should have been 0.43 W/m2. More than 70% of it is nowhere to be found. And not even feedbacks are taken into account yet. With them the effect measured is barely more than 10% of the radiative imbalance projected by IPCC.
The artificial jump of 2003 introduced by Levicus at al. would not improve the situation much. It would make the figure above 15-20% perhaps (of expectations based on mainstream climate science).
Either OHC history reconstructions are useless or theory misses some strong negative feedback.
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Doug Bostrom at 00:39 AM on 8 April 2010Ocean acidification: Global warming's evil twin
fydijkstra, it seems this word "acidification" touches a hot button for a lot of folks, perhaps the same way as does thinking of C02 as a pollutant. When the relative pH number is reduced, a solution is said to be "acidified." It's a convention in our language you're not going to be able to change. It's the same deal as speaking of relative temperature. A gas at 2,500 degrees C is said to "cool" if its temperature is later found to be at 2,400 degrees centigrade. It's not cool by any means, but it has cooled. Easy, eh? Getting hung up on this point does the rest of your post no credit. -
gallopingcamel at 00:35 AM on 8 April 2010What CO2 level would cause the Greenland ice sheet to collapse?
Ned (#80), My apologies for taking so long to get back to you. The response from Environment Canada arrived a few minutes ago. Here it is: From: Env Canada Weather-Météo
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