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Berényi Péter at 06:13 AM on 9 April 2010Ocean acidification: Global warming's evil twin
#35 Ned at 00:52 AM on 9 April, 2010 Your flat assertion that the existence of natural variability around the mean somehow immunizes the ecology to variability in the mean seems to be unjustified. It would be unjustified indeed had I claimed such a thing unconditionally. However, it was not the case. I said it should not have observable effect provided shift is negligible compared to natural variability. If diurnal pH changes up to 1 pH do occur in coral reefs with no devastating consequences, a less than 0.1 pH change since 18th century is insignificant. BTW, I wonder how they figured out how much average ocean pH was 250 years ago with such accuracy. -
Doug Bostrom at 05:57 AM on 9 April 2010CO2 has a short residence time
N/A, read Spencer Weart's book for a thorough background on this topic. To get directly to the point you raise, you might start with chapter two, The Carbon Dioxide Greenhouse Effect Long story short, we've got a robust set of reliable physics tools found amply predictive in a plethora of applications including this particular case coupled with extensive laboratory experiments and a record of field observations as well as models of climate behavior, all mutually consistent and all leading inexorably to the notion of additional C02 in the atmosphere causing an increased temperature of the part of the Earth we're concerned with. At this point, the onus is on folks choosing to disagree with all of the above to state a persuasive case of why and how all those things should fail in a way that does not upend much of what we think we understand of radiative physics, the ideal gas law and much else. That's a steep hill to climb, nobody's yet made it to the top. -
Ned at 05:55 AM on 9 April 2010CO2 lags temperature
Science doesn't tell us what is "good" or "bad." Those are value judgments. Science tells us "If you increase the radiative forcing from greenhouse gases, the planet will warm." Whether that's good or bad, or more likely some mixture of both, depends on your viewpoint. Your repeated insistence that you want people to focus more on value judgments while simultaneously insisting that you want the discussion to be more scientific seems irreconcilable to me. -
Ned at 05:49 AM on 9 April 2010CO2 has a short residence time
N/A, we've "convicted" CO2 of causing warming for physical reasons, not just because of statistical correlations. In fact, Arrhenius predicted that CO2 would cause warming long before we had any of the data showing these correlations. Some of the reasons for believing that CO2 is responsible for the warming are discussed on the page How do we know CO2 is causing warming?. -
nhthinker at 05:31 AM on 9 April 2010CO2 lags temperature
Actually, the purpose of this site seems to be to cite scientific literature that CO2 from humans causes warming and warming in the short term is necessarily bad. That there seems to be an aversion to discuss why some level of human caused CO2 may be necessarily good and an aversion to interest in understanding what that level would be seems like it has some non-scientific motivations to me. If you are interested in CO2 but not interested it what the optimum level that the humans should keep in the atmosphere to balance all the potential disasters, seems kind of limited scope of inquiry to me. If you want to take the position that the "right" level of CO2 would be the level that would occur without humans, then say so. Such a position does not have a scientific basis unless you consider humans unnatural. -
CO2 has a short residence time
With climate science as in astronomy when we are looking into past events, it is hard to distinguish between circumstantial evidence, theoretical conjectures, and thought experiments which supports a given hypothesis which may not be falsifiable (i.e., it cannot be refuted or replicated by experiments. Thus it is easy to mistake a correlation with cause and effect. Can you give some advice on how one can untangle this confusion? What repeatable experiments have been done or can be done in a high school lab to show that global warming is "caused" not "correlated" with a rise in CO2 and is due only to the onset of the industrial age and is not caused by something else? What does it take to transform a correlation into a cause? It only takes one valid counter example to demolish a hypothesis. Are all the proposed counter examples for the predominant cause of global warming proven to be invalid or cannot be proven by experiment. Is it possible to have two contradictory hypotheses about global warming which are not falsifiable. That is, they cannot be proven by experiment. -
Berényi Péter at 04:46 AM on 9 April 2010Skeptical Science Housekeeping: Preview, translations and icons
Thanks for the preview. I'll certainly use it (I know who I am :) -
Ned at 04:44 AM on 9 April 2010CO2 lags temperature
nhthinker writes: The inability of scientists here to discuss what the "right amount" of extra CO2 is the appropriate amount to balance the short term needs versus the long term needs of humanity seems like a very unscientific approach to me. The fact that people don't choose to discuss things in the way you want doesn't imply any "inability" or "unscientific approach" on their part. -
Ned at 04:38 AM on 9 April 2010CO2 lags temperature
nhthinker writes: What problem do you have with use of the term "apocalyptic" to describe the hostility to life of the next ice age? Well, it's awfully slow for an "apocalypse" since it develops slowly over a period of tens of thousands of years. Also, of course, humans have already lived through multiple glacial/interglacial cycles and in fact dramatically expanded our geographic range, our population, and our behavioral development (language, tool usage, etc.) right smack in the middle of the last glacial cycle. Do you know of an adjective that would be more accurate to describe a planet that has lost 80% of its biomass to premature death and starvation? Source, please. Where does that 80% come from? "Premature death and starvation" seems a bit overdramatic for something that only transpires slowly over a period of millennia. You carefully avoided the answer as to whether humans should do what is scientifically necessary to prevent the next ice age. (A response like "we're doing it anyway" is not an answer). Again, I'd recommend a little more politeness and a little less confrontational style. I haven't avoided any question in this thread. We are, of course, actually in an ice age. As I understand it we're near the start of an interglacial that would probably last for another 50,000 years even if we didn't burn another kg of coal or oil. To answer your question directly, I don't think we should lift a finger to "prevent" the next glacial advance. I think our descendants 2000 generations in the future should be able to decide how they want to handle it. In fact, if burning fossil fuels and raising the CO2 concentration of the atmosphere were the best way to prevent a future glacial advance, that would be all the more reason to reduce our consumption of fossil fuels now and save some for the future generations who will really need them, right? Following your logic, we're currently wasting precious resources that will be desperately needed by our 2000x-great-grandchildren in AD 50,000. More to the point, worrying about the next glacial advance (which almost certainly won't happen for 50,000 years, and if we burn enough carbon may not occur for 500,000 years or more) is rather foolish when the next century or two will experience serious environmental problems caused by too much warming and the resulting alterations of the hydrologic cycle. What you're suggesting is analogous to worrying about flooding in the middle of a drought. We should focus on more immediate concerns. -
nhthinker at 04:19 AM on 9 April 2010CO2 lags temperature
The entire purpose of this forum is to link to scientific literature that human introduced CO2 is causing global warming and the clear implication here is that extra CO2 is a bad thing. The inability of scientists here to discuss what the "right amount" of extra CO2 is the appropriate amount to balance the short term needs versus the long term needs of humanity seems like a very unscientific approach to me. You are welcome to call it "policy" question. To me, it clearly has its roots in scientific exploration of causes and effects and near term disasters versus long term disasters. But it's your site and you are welcome to limit it to discuss the limited inquiry you want. Cheers. -
citizenschallenge at 04:07 AM on 9 April 2010Skeptical Science Housekeeping: Preview, translations and icons
Fantastic and thank you John. . . . . . and thanks to all the other folks helping you keep this site going and improving. For myself, you have leap-frogged all the previously top rung AGW information websites. They are still valuable and needed, but for the interested lay-person I believe Skeptical Science is the number one spot going!!! Peterm And the Preview button is genius ;-) -
Tom Dayton at 03:54 AM on 9 April 2010CO2 lags temperature
nhthinker, what you're now focusing on is a policy question that is off topic for this thread on CO2 lagging temperature:I assert that humans should intentionally do what ever necessary to prevent the next ice age. It should be done with a significant safety margin of error to account for unusual but expected events like massive volcanoes and asteroid hits. Do you disagree? If so, why?
I'm not sure whether there is an appropriate thread on this Skeptical Science site, since this site focuses on science rather than policy. But you might try The Upcoming Ice Age Has Been Postponed Indefinitely, or maybe Are We Heading Into A New Ice Age? Please don't be upset if off-topic posts get deleted from any of the threads, though. -
Doug Bostrom at 03:48 AM on 9 April 2010CO2 lags temperature
Nhthinker, you've been provided with excellent information indicating that perhaps 40,000 years from now we should consider another ice age to be reasonably imminent. Right now we have a more urgent problem erupting under our feet, multiple lines of evidence indicating we're in some degree of difficulty due to C02 pollution. Why not check back here in, say, 35,000 years? Meanwhile the rest of us will get on with solving the present issue. -
CBDunkerson at 03:48 AM on 9 April 2010Skeptical Science Housekeeping: Preview, translations and icons
Even as someone who has been using HTML for years I'm glad to see the preview button as there have been several times that I have wondered things like, 'does this site support font tags?' and either taken them out or just went ahead and hoped for the best. That said, please note Ned's comment above about 's and, as you can see in my text above, the fact that if you hit preview a few times these 's are actually accumulating in the comment box and will come out in the final note if not removed.Response: Fixed the accumulating slashes glitch, thanks for pointing this out. -
nhthinker at 03:14 AM on 9 April 2010CO2 lags temperature
What problem do you have with use of the term "apocalyptic" to describe the hostility to life of the next ice age? Do you know of an adjective that would be more accurate to describe a planet that has lost 80% of its biomass to premature death and starvation? You carefully avoided the answer as to whether humans should do what is scientifically necessary to prevent the next ice age. (A response like "we're doing it anyway" is not an answer). I assert that humans should intentionally do what ever necessary to prevent the next ice age. It should be done with a significant safety margin of error to account for unusual but expected events like massive volcanoes and asteroid hits. Do you disagree? If so, why? If there is full agreement from scientists that humans should, for the good of future generations assure that an "unnatural" amount of CO2 should be kept in the atmosphere to prevent an ice age, then who decides what the right added level should be? Those that are only concerned and emotionally connected with their immediate offspring? Or those that have a more balanced concern with the long term? Were the dramatic changes to climate/environment caused beavers considered "natural" because the they were not self-aware of their impacts? Are the changes to the environment changed by self-aware beings any less natural? To see a difference between the beavers and the humans is to agree with the druids. -
Chris G at 02:52 AM on 9 April 2010Ocean acidification: Global warming's evil twin
Ah, I think I detect a pattern related to the preview pane. Look's like apostrophes are escaped as part of coping with XML(?) in the preview, but not returned to original when submitted. It's a minor defect. -
Doug Bostrom at 02:50 AM on 9 April 2010Humans are too insignificant to affect global climate
Because it's a hobby horse for me, let me amplify Ned's remark about our crude habit of burning our petroleum. Not only is petroleum pyromania pathetically primitive, but burning this resource will seriously balloon our future energy requirements while simultaneously throwing sand into the gears of our economy. Using petroleum for liberation of heat via combustion is a wretched waste that is going to come back and haunt us in a bad way. We're heavily dependent on polymers made from oil. Nearly all of our daily activities are dependent on products made using petroleum feedstock. That's because the simple molecule of methane and all of its more evolved and advanced cousins are absolutely fabulous structures for rearranging into different configurations, tweaking with the addition of other components and then creating useful things. All of that hydrogen and carbon we lean on was jammed together for free, eons ago, over plenty of time when nobody was tapping their foot waiting for their next roll of polyethylene, collection of O-rings, damping bushing, etc. As we burn what could be made into relatively durable and incontrovertibly essential artifacts, we're going to see the prices of nearly every product we use steadily creep upward quite independent of direct impacts of rising motive power costs. If we continue to burn petroleum willy-nilly as we do now, our requirement for hydrocarbon feedstock to produce things we need will collide with insufficient supply. At that point, we're going to have to -manufacture- methane and all its more useful cousins, and that's going to require a staggeringly large amount of of energy. Marrying hydrogen and carbon is only possible with a large energy dowry, which of course is why the stuff burns so nicely. That energy demand is going to be stacked on top of what will already be a horrendous challenge, that of substituting for and eliminating hydrocarbons for thermal applications such as heating and motive power. We really do need to change our approach to how we use petroleum. We can start by recognizing what rotten stewards of this resource are our petroleum producers, refiners and marketers, how defective is their drive to encourage waste. However, they're not really the primary problem. These entities have commercial considerations compelling them to encourage us to be thoughtless, feckless consumers. At the end of the day, it's up to us to cease our fascination with igniting petroleum and instead consider it irreplaceable, something to be husbanded jealously. -
Chris G at 02:49 AM on 9 April 2010Ocean acidification: Global warming's evil twin
I\'ve been thinking for some time that ocean acidification is potentially a bigger problem than sea-level rise, maybe even bigger than climate zone shifts. But, I haven\'t been able to bridge the gap between impacts to specific species of foraminifera and impacts to people. I\'ve read speculations that we might want to develop a taste for jellyfish, but I suspect there exists information on the food chain dependencies on the threatened foraminifera and the subset of those chains on which a lot of people are dependent for food. Any pointers? RobHon #16, my sister and I happen to have graduate degrees in psych, though I went the cognitive route (and ended up in a not in a research career) and she went social and teaches at university, your thoughts are within the realm of how I remember things in that area. I don\'t know the answer; attempts to ease the dissonance are often seen as attempts at manipulation. Defense mechanisms kick in (It\'s really hard to admit even to yourself that your actions cause harm to others.) and further attempts are most often met with hostility. Kind of like trying to force water on a dehydrated person, they don\'t feel thirsty, but you have to keep making water available. -
Doug Bostrom at 02:20 AM on 9 April 2010Visual depictions of Sea Level Rise
BP, you should take a look at David Roper's site: Sea Level Versus Temperature He's not in sync w/you regarding his conclusions but I'm pretty sure you'll enjoy looking at his methods. -
Chris G at 02:01 AM on 9 April 2010Ocean acidification: Global warming's evil twin
Bern, I don't have time to back you up with real papers at the moment, but I was thinking the same thing. For a 1st-order assessment, I imagine an overlay graph of the lifetimes of sulfates, particulates, CO2, whatever, and the different rates, and opposing effects, determine that a climate roller-coaster was likely. As well, systems tend to 'wobble' for a while after a disturbance, as inertial effects often cause an overshoot of equilibrium. -
Ned at 01:53 AM on 9 April 2010CO2 lags temperature
nhthinker writes: Using your daughter is clearly an emotional argument- any scientist can recognize that. Is this a forum for emotional arguments? I don't see any problem with John mentioning his daughter. Many of us who are scientists do in fact have young daughters, and being normal human beings we may be a bit more motivated in our work by the desire to make the world a better place for them to grow up in. In any case, it seems less problematic than your own use of "apocalyptic ice age" and "druids" above. Maybe when you're just starting out participating here you might want to be a little less confrontational? Just a suggestion. -
Chris G at 01:49 AM on 9 April 2010Ocean acidification: Global warming's evil twin
Ned, No worries. Actually, when I first read it, I assumed you were having a poke at the anti-AGW argument regarding the correlation of CO2 and global temps, or anything where the causation can be determined by physics, and not by simply looking at the stats. Cheers -
billkerr at 01:48 AM on 9 April 2010Are we too stupid?
wrt the nuclear issue fast breeder reactors (Gen IV) use existing wastes as fuel and only 1% remains as waste, compared with 99% of Gen II reactors. Nuclear is safer than coal. The only real problem is that nuclear is still more expensive. Barry Brook's Brave New Climate is a well informed pro nuclear site based on the premise that AGW is a real problem. Also Tom Blee's book Prescription for the Planet is an interesting read mainly for his knowledge of the Integral Fast Reactor but he has other interesting ideas too, such as the boron fueled car. -
Ned at 01:45 AM on 9 April 2010Skeptical Science Housekeeping: Preview, translations and icons
Tom writes: \"Thanks for the Preview button, John! Unfortunately it seems to be absent from the Arguments pages. \" Also, I notice that when I click the Preview button it adds back-slashes (\) before any quote-marks in my comment [see above]. That said, thanks for doing this. I apologize for all the times I've messed up my HTML (or just written the wrong thing) and I'll endeavor to make good use of the Preview button in the future. -
Ned at 01:42 AM on 9 April 2010Ocean acidification: Global warming's evil twin
Chris G writes: Ned (#2 & #3), I don\'t know, there\'s a correlation there, but you can\'t prove causality. :-P My motto is "Post in haste, repent at leisure." I think my frequent mishaps and typos probably helped provoke John into adding the "Preview" button. -
Ned at 01:37 AM on 9 April 2010CO2 lags temperature
Whoops, Tom has the name right and I have it wrong. It's Berger and Loutre, not Loulette. And when I write "If our understanding of that threshold is correct, it's possible ..." that should be incorrect not correct. Sorry for the confusion. -
Chris G at 01:34 AM on 9 April 2010Ocean acidification: Global warming's evil twin
Ned (#2 & #3), I don't know, there's a correlation there, but you can't prove causality. :-P -
Ned at 01:33 AM on 9 April 2010CO2 lags temperature
nhthinker writes: Please reference the peer reviewed article that claims to know that the next ice age will definitely not occur for the next 50,000 years. "Definitely" is not a word that's used much in the geosciences. The last couple of interglacials were relatively short, but in recent years people have realized that neither of them is a particularly good analog for the Earth's current orbital geometry, and that comparison to the MIS-11 interglacial is more apt (Berger and Loulette 2002). Even without any anthropogenic CO2, this yields a long interglacial followed by a descent into glacial conditions around 50k years from now:
Long-term variations of eccentricity (top), June insolation at 65°N (middle), and simulated Northern Hemisphere ice volume (increasing downward) (bottom) for 200,000 years before the present to 130,000 from now. Time is negative in the past and positive in the future. For the future, three CO2 scenarios were used: last glacial-interglacial values (solid line), a human-induced concentration of 750 ppmv (dashed line), and a constant concentration of 210 ppmv (dotted line). Simulation results from (13, 15); eccentricity and insolation from (19). (Berger and Loulette 2002).
See also the subsequent work by David Archer, described in his book The Long Thaw and in various papers, such as Archer et al. 2005. Archer notes that the projected insolation will come close to the apparent threshold for glaciation in a few thousand years, then move away from that threshold and not cross it until 50k years from now.
If our understanding of that threshold is correct, it's possible that a mild return to glacial conditions could start in a few thousand years from now. But the most likely scenario is that it won't happen for another 50k years. That's without additional CO2. Here's what Archer et al. 2005 say about adding CO2:
"Release of 1000 Gton C (blue lines, Figure 3c) is enough to decisively prevent glaciation in the next few thousand years, and given the long atmospheric lifetime of CO2, to prevent glaciation until 130 kyr from now. If the anthropogenic carbon release is 5000 Gton or more (red lines), the critical trigger insolation value exceeds 2 s of the long-term mean for the next 100 kyr. This is a time of low insolation variability because of the Earth’s nearly circular orbit. The anthrogenic CO2 forcing begins to decay toward natural conditions just as eccentricity (and hence insolation variability) reaches its next minimum
400 kyr from now. The model predicts the end of the glacial cycles, with stability of the interglacial
for at least the next half million years (Figure 3c)."
nhthinker writes: Why won't you answer the question about the beavers?
I'm not sure I understand your point. If your comment above is imagining a hypothetical situation where beavers become intelligent, industrialize, and start to double to CO2 concentration in the atmosphere, then yes, once their scientists understood the probable climate impacts of their activities they would probably be well advised to modify their ways and develop better technologies.
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Tom Dayton at 01:23 AM on 9 April 2010Skeptical Science Housekeeping: Preview, translations and icons
Thanks for the Preview button, John! Unfortunately it seems to be absent from the Arguments pages.Response: I wondered who would bring that up :-) I've now added the Preview button to the argument pages. -
Tom Dayton at 01:11 AM on 9 April 2010CO2 lags temperature
njthinker: An article by Berger and Loutre (2002) explained why this interglacial could last 50,000 years past today. The exact number of thousands of years is estimated differently by different researchers; 50,000 is the current best estimate, but nearly all researchers agree that the number is in the tens of thousands of years from now, and all researchers agree that the number is many thousands of years from now. You can learn more about the triggers of ice ages by entering "Milankovitch" in the Skeptical Science "Search" field at the top left of every page. -
Steve L at 01:11 AM on 9 April 2010Ocean acidification: Global warming's evil twin
Again, the analogy between anthropogenic acidification denial and debunked AGW-denier arguments is remarkable. "We experience daily temperature fluctuations greater than the projected average temperature increase by 2100; therefore AGW is no big deal." Average surface water in the North Pacific will be unsaturated for Aragonite in the North Pacific by 2100? Don't worry! Small volumes are ephemerally unsaturated for Aragonite even now, and there are still pteropods. -
Jim Powell at 01:03 AM on 9 April 2010Ocean acidification: Global warming's evil twin
Wikipedia has an interesting chart on Ocean Acidification:
ocean pH between the 1700s and the 1990s.
According to Wikipedia
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Steve L at 01:00 AM on 9 April 2010Skeptical Science Housekeeping: Preview, translations and icons
You can lead a horse to water, but can you make me properly use a preview function? -
Ned at 00:52 AM on 9 April 2010Ocean acidification: Global warming's evil twin
BP writes: If natural variability is high, a little drift does not make any difference. How do you know that? Let's say a species is existing near the limit of its range in a given parameter (temperature, moisture, pH, whatever). There's some range of variation s around the mean x of that parameter which it has to be able to cope with. In other words, it has to be able to survive and reproduce through the range of conditions [x-s, x+s]. Now perturb x upward or downward to x'. That natural variability s doesn't disappear. The species is now subject to the range [x'-s, x'+s]. That's a different range of conditions and there's no guarantee the species will be able to survive under this new range. Of course, s may also change. That adds to the uncertainty. Your flat assertion that the existence of natural variability around the mean somehow immunizes the ecology to variability in the mean seems to be unjustified. -
Berényi Péter at 00:39 AM on 9 April 2010Ocean acidification: Global warming's evil twin
#29 Riccardo at 22:19 PM on 8 April, 2010 Modulation is one thing, long term decrease, eventually modulated, is another Of course it is, for us. For the creatures living there it is all the same. If natural variability is high, a little drift does not make any difference. -
Steve L at 00:33 AM on 9 April 2010Ocean acidification: Global warming's evil twin
Answer to malcuk @31: yes. -
cbrock at 00:24 AM on 9 April 2010Skeptical Science Housekeeping: Preview, translations and icons
John: Thanks for the expansion and improvements to Skeptical Science. This site is the number-one place to send those relatives and friends who have heard mutterings about the so-called fallacy of AGW but truly want more information--a place largely free of rancorous tirades and name-calling. A call to readers to add translations for French, Russian, and Hindi. Also remember to click on the donate icon to help John maintain and expand this site! -
dhogaza at 00:23 AM on 9 April 2010Ocean acidification: Global warming's evil twin
The sad thing about JRuss is that he substitute teaches classes, including science classes, in public schools. The "pools of CO2 at the bottom of the ocean" and stuff like this being taught to our children? Ooof. -
nhthinker at 00:02 AM on 9 April 2010CO2 lags temperature
The study you quote only indicated half a million years for 5000 gigatonnes. (And note these are just projections). Please reference the peer reviewed article that claims to know that the next ice age will definitely not occur for the next 50,000 years. Using your daughter is clearly an emotional argument- any scientist can recognize that. Is this a forum for emotional arguments? Why won't you answer the question about the beavers? -
malcuk at 23:53 PM on 8 April 2010Ocean acidification: Global warming's evil twin
Ah, was just being stupid I think (re my comment #30). Is a 0.1 decrease in pH roughly the same as a 26% increase in H+ in the water? -
nhthinker at 23:43 PM on 8 April 2010CO2 lags temperature
Use of the phrase "arguably occur hundreds of thousands of years in the future" is only consistent with your quoted scientific projections if and when the CO2 release reaches 5000 gigatonnes. Are you proposing that we should reach that level? Your reference to your daughter seems inconsistent with your stated posting policies.Response: If we emit 5000 gigatonnes of CO2, the ice age is postponed indefinitely. If 1000 gigatonnes, then still over 100,000 years. We've already gone past the 300 gigatonne mark which will postpone the ice age for at least 50,000 years. If you want to haggle over numbers, let's adopt the most pessimistic worst-case-scenario and say we're staring down the barrel of an ice age in 50,000 years.
I'm not sure which posting policy I've violated - it seems fairly straightforward that immediate generations are a higher priority than descendents over 5000 generations away. -
malcuk at 23:25 PM on 8 April 2010Ocean acidification: Global warming's evil twin
I am finding this discussion of "pH units" a little uncomfortable. As I understand it, pH is a logarithmic scale, so a change of 0.1 pH units means a different change in H+ concentration depending on the starting pH. Is there data on the % change of H+ concentration, or would this be misleading? -
nhthinker at 22:59 PM on 8 April 2010CO2 lags temperature
On average, the climate of the last quarter million years have been very much less hospitable to humans and all life in general. It is less than 20% of time that the climate stay hospitable. Should humans allow the climate to naturally ebb back into terribly inhospitable cold? Do we actually know the mechanisms humans can use to delay the onset of the next apocalyptic ice age? Isn't the prevention or delay of ice ages terribly more important than slight rises in temperature? Do the druids and "humans should have no climate impact" scientists agree that allowing the globe to slip into the next ice age would be a bad thing? Somehow, I don't think so. Beavers had dramatic impact on climate and terrestrial life: If they had become smart enough to become self aware, should they have stopped transforming the planet?Response: The possibility of heading back into another ice age has been examined on multiple occasions in the peer-reviewed literature. Ice ages begin when northern ice sheets encroach further southward from year to year, gradually increasing the Earth's albedo. So if a huge ice sheet takes over northern Canada, then yes, be concerned.
But in the meantime, the two largest ice sheets in the world, Greenland and Antarctica, are losing ice mass at an accelerating rate. You can rest assured that the imminent ice age has been postponed indefinitely. On the contrary, the accelerating mass loss from these ice sheets is predicted to raise sea levels by 1 to 2 metres by the end of this century. For the sake of my 10 year old daughter, I'm more concerned about the 1 to 2 metres sea level rise she'll see in her lifetime than a hypothetical ice age that will arguably occur hundreds of thousands of years into the future. -
Ned at 22:40 PM on 8 April 2010A database of peer-reviewed papers on climate change
Poptech, it's also worth noting this. From your comment above: [E&E is] Found at 44 libraries worldwide, at universities and the library of congress. Including an additional 78 in electronic form. That seems to be about the right order of magnitude. WorldCat says E&E is currently in 48 libraries worldwide. Now, that's a really, really small number of libraries. My own field is pretty narrow, and the journals are going to be inherently of less wide interest than a journal that publishes papers on "environment" and "energy" topics. I just looked up all of the main journals in my field, and they're all in at least 400-600 libraries according to WorldCat. As far as I can tell, E&E is part of a parallel infrastructure that's grown up to provide a safe and un-skeptical venue for promoting work that (a) questions the mainstream scientific consensus on climate change, and (b) isn't of high enough caliber to be considered in a "real" scientific venue. So, for example, there's the "NIPCC" report created by Fred Singer as a kind of shadow version of the actual IPCC reports. There's the Heartland climate "conference" which is likewise a kind of weak and nonserious response to actual scientific conferences (AGU, etc.). And then there's E&E, kind of a toy journal for outside-the-mainstream papers only. The advantage of publishing in E&E rather than a real journal, or presenting at a Heartland event rather than a real conference, is that your work won't actually be subjected to any kind of skeptical review. -
Berényi Péter at 22:28 PM on 8 April 2010Visual depictions of Sea Level Rise
OK. I have visited the University of Colorado at Boulder Sea level change site and downloaded Global mean sea level satellite data (Inverted barometer applied, Seasonal signal removed, 1993-2009). It looks like this:
I have calculated least square fit quadratic. It turns out sea level rise is actually decelerating in this 16 years long period. Acceleration term is -0.108 mm/y2.
If linear term is also considered valid and current trend is extrapolated, sea level rise should stop by 2030 (21 mm above current level). Beyond that time it would start decrease. By 2100 sea level would be some 25 cm lower than now, decreasing at a 7.5 mm/year rate.
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Riccardo at 22:19 PM on 8 April 2010Ocean acidification: Global warming's evil twin
Berényi Péter, "natural pH cycles can modulate the impact of ocean acidification on coral reef ecosystems." This is the conclusion of the original Pelejero et al 2005 paper that you did not quote. Modulation is one thing, long term decrease, eventually modulated, is another. -
Ned at 22:07 PM on 8 April 2010A database of peer-reviewed papers on climate change
Poptech, nobody (outside their editorial team) really knows how "review" functions at E&E. However, the proof of the pudding is in the eating as they say, and there is a long history of seriously and obviously flawed papers coming out in that journal. So either they're not being reviewed, or they're not being reviewed effectively. In either case the result is the same. Most scientists will (rightly, in my opinion) feel that it's not worth their time to read papers from E&E. Given the huge expansion in the number of journals and the number of papers being published, it's difficult enough to keep up with the literature as it is! -
Ned at 21:50 PM on 8 April 2010Humans are too insignificant to affect global climate
jmymac1958, you're comparing the quantity of CO2 emitted from burning gasoline to the total atmosphere. But the atmosphere is mostly made up of inert nitrogen and oxygen, which are irrelevant to the radiation balance. Instead, you need to compare the increase in CO2 to the total quantity of CO2. The mass of CO2 in the atmosphere is about 3E15 kg. The mass of CO2 produced annually by burning gasoline in the US is 1.2E12 kg. So US gasoline consumption increases CO2 in the atmosphere by about 0.04%. That's a small amount. But it accumulates over time, due to the long lifetime of CO2 in the atmosphere, and gasoline in cars is not the only source of CO2 (see coal, natural gas, and petroleum not used in cars), and the US isn't the only country in the world. Thus, in a fairly short time, we are doubling the concentration of CO2 in the atmosphere ... even in spite of the fact that some of the CO2 we produce is taken up by the oceans and the biosphere. It is sometimes hard to believe that a small quantity of something can have a serious impact. The lethal dose for arsenic is around 13-14 parts per million, for dioxin it's 0.02 parts per million (0.000002%). As John points out, it's quite possible to reduce our CO2 emissions with current technology and without destroying the economy. The Socolow and Pacala 2004 paper is a good place to start. And as Doug points out, we're going to have to move away from fossil fuels anyway, so why not start now? Oil is a very valuable substance for manufacturing and industry; it's stupid to just burn it all. Doesn't it seem a bit selfish to take a valuable resource that's accumulated over hundreds of millions of years and burn it all in the course of a century or so? One assumes that human civilization will still be around past 2100; even if you ignore the climate issue our descendants may not appreciate our profligate squandering of their inheritance. Finally, I'd politely suggest not making ad-hominem remarks in your posts (e.g., your references to Al Gore). It's much better to make your point without name-calling or insults, no matter how subtle and humorous you think you're being. -
Ned at 21:04 PM on 8 April 2010Ocean acidification: Global warming's evil twin
JRuss, in addition to the mysterious "pools of liquid CO2" comment, I'd like to highlight this, which is also incorrect: 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. As long as humans are burning large quantities of fossil fuels, the direction of the CO2 flux is from the atmosphere to the ocean. It's true that warmer waters hold less CO2, but that means the oceans will take up less CO2 from the atmosphere, not that the oceans will be a net source of CO2 to the atmosphere. See: * Sabine et al. (2004). The Oceanic Sink for Anthropogenic CO2. Science, Vol. 305. no. 5682, pp. 367 - 371. * Takahashi et al. (2009). Climatological mean and decadal change in surface ocean pCO2, and net sea–air CO2 flux over the global oceans. Deep Sea Research Part II: Topical Studies in Oceanography Volume 56, Issues 8-10, Pages 554-577. -
Berényi Péter at 20:23 PM on 8 April 2010Ocean acidification: Global warming's evil twin
Local diurnal/seasonal/interdecadal pH variability is rather larege comparedt to projected changes. Therefore marine ecosystems must have been evolved to deal with such excursions. Response to Comment on "Preindustrial to Modern Interdecadal Variability in Coral Reef pH" Pelejero & al. Science 27 October 2006: Vol. 314. no. 5799, p. 595 DOI: 10.1126/science.1128502
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