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cjshaker at 06:03 AM on 5 December 2010We're heading into an ice age
Daniel Bailey asks And your source for that claim would be...? Re: cjshaker >"I think the bottom line is that climate modelers don't really understand the glacial >cycle, nor how it really works." I make that claim because of articles like this one, which appear to show poor ability to predict the glacial cycle using models http://www.igsoc.org/annals/5/igs_annals_vol05_year1984_pg213-214.pdf And this one, which attempts to use spectral analysis to predict future behavior of the glacial cycle http://www.nosams.whoi.edu/PDFs/papers/surveysingeo_time_series.pdf Chris Shaker -
Albatross at 05:19 AM on 5 December 2010A basic overview of Antarctic ice
Bill, "Since it appears to be statistically insignificant it probably either is or very close to it." Now the goal posts shift, again. OK, I'll look into that for you. But I have a bunch of things to take care of this weekend...so please be patient. Actually, I do not have the global data for sea ice. Those data I showed earlier were area from NSIDC while the graph I posted was extent data from "Cryosphere today". PS: I have not "cherry-picked" data, nor is applying an OLS model and stating the statistical significance of the model fit "arm waving". The reason for me selecting the months I did is because (if you have read the original post) we have been discussing the impact of changes in albedo around the time of the solstices. -
actually thoughtful at 05:01 AM on 5 December 2010Renewable Baseload Energy
Based on this thread, I have come to some conclusions for energy goals in the United States. Currently electricity comes from the following sources: 2005 energy production
Source:
http://montaraventures.com/blog/2006/10/09/how-does-the-us-produce-electricity/
So, we need a future that is different. Based on the statement that 60% of energy consumption is baseload, we should aim for for a fossil free future that looks something like this:
coal 0%
nuclear 30%
petroleum 0%
hydro 5%
renewable 65%
gas backup (normally not used, but available): 20%
This will require an intermediate stage where gas takes on a larger role as we get off of coal and ramp up renewables and supporting technologies.
Moderator Response: Fixed image tag. -
Bob Guercio at 05:00 AM on 5 December 2010Stratospheric Cooling and Tropospheric Warming
Folks, I corresponded via email with a distinguished professor at Rutgers and this is that correspondence. Dear Bob, You correctly wrote up what Gavin told you, but he is wrong. The stratosphere cools because its emissivity goes up with more CO2, and it still absorbs the same amount of energy being emitted from below. It is a balance of energy. You cannot just look at one term. Designing a graph with not enough room to do it correctly is not a good reason in my opinion to do it wrong. Alan Alan Robock, Professor II (Distinguished Professor) Editor, Reviews of Geophysics Director, Meteorology Undergraduate Program Department of Environmental Sciences Phone: +1-732-932-9800 x6222 Rutgers University Fax: +1-732-932-8644 14 College Farm Road E-mail: robock@envsci.rutgers.edu New Brunswick, NJ 08901-8551 USA http://envsci.rutgers.edu/~robock On 12/2/2010 10:22 AM, Robert Guercio wrote: > Dear Alan, > > I'm sure you're correct; however, here is the email correspondence > that I had with Gavin. > > The ordinate should be (watts/meter square wavenumber) and I had > trouble making it all fit. I was actually working pixel by pixel and > I guess I was a bit lazy but that is easily corrected. > > The solar insolation that I used was very fictitious as everything > about my model is. I just kept on playing with different numbers > until the fictional atmosphere that I came up with made for "good" > graphs. > > Bob > > > > ----- Original Message ----- From: "RealClimate" > -
cjshaker at 04:55 AM on 5 December 2010Ocean acidification isn't serious
The bleaching of coral reefs seems to actually be caused by fungus, which is transported across oceans by dust in the wind as the climate naturally warms and dries. http://imars.usf.edu/~cmoses/PDF_Library/Shinn%20et%20al%202000.pdf It looks like fungi have been attacking coral reefs for a long time http://www.biolbull.org/cgi/reprint/198/2/254.pdf Chris Shaker -
Bob Guercio at 04:50 AM on 5 December 2010Stratospheric Cooling and Tropospheric Warming
Sphaerica So CO2 prevents energy from escaping from the troposphere into the stratosphere in the CO2-IR bandwidth, My blog does this. and CO2 actively cools the stratosphere by emitting energy in the CO2-IR bandwidth. Once I fully understand this, I'll incorporate it into my blog and maybe it will be complete. This sentence that you wrote would be part of my opening statement. And then my blog, as it is now, would address the first method and I'll then add the second method. This has been like wrestling an alligator. The problem is that, as far as professionals are concerned, all this is so trivial that they wouldn't waste their time on it. It's probably in some climate textbook or maybe not; maybe it's a problem at the end of some chapter on stratospheric chemistry or some such name! Thank you, Bob -
Albatross at 04:42 AM on 5 December 2010The human fingerprint in the seasons
HR @55, "So fingerprint = correlation? Is that all? Wow." Umm, not quite. Read some more of Santer's seminal works. Earlier you said "The problem I have is that those two options aren't the only possibilities." Referring to options other than solar and volcanic forcing. But then @ 55 you misrepresent the findings form a study to try and support the “it’s the sun” argument. Also, I asked you to present a model here which does not include solar or volcanoes and that explains the nature of the observed long-term warming trend. -
Billhunter at 04:32 AM on 5 December 2010A basic overview of Antarctic ice
Philippe Chantreau at 03:04 AM on 5 December, 2010 "I don't know how one can look at the data and come to that conclusion. Whatever analysis this assertion is based on is in error. The decline of global sea ice is statistically significant." The claim was made based upon a monthly analysis that ice gain in the Antarctic which also is visibly easy to see on a graph was NOT statistically significant. Thus the appropriate response would be that since there is a positive trend provided by the southern ice that reduces the loss of Arctic ice by nearly half on a month by month basis that the trend globally may also not be statistically significant. When one decreases the percentage of ice loss by both increasing the denominator and decreasing the numerator a mathematical answer is called for. Saying it is easily visible is not an appropriate response when somebody had already responded that something that is easily visible mathematically is not significant. (i.e. antarctic ice gain). The correct response is a third category, which Albatross can easily do as he obviously already has all the data and we can get away from the highly unscientific approach of arguing via cherry picking mathematical tests vs visual tests. All that is required to test this hypothesis is to add the two categories together in post #74 and do the math. An interesting variation if our objective is to test the statistic significance of the "pole" albedo issue would be to add in the land mass of antarctic as virtual sea ice serving the same purpose the core area of the Arctic serves. In that way we could test the statistical significance of "pole" ice. Then we can really begin to treat these issues consistently and better weigh the significance of each argument in a consistent manner without a lot of arm waving. -
Bob Guercio at 04:23 AM on 5 December 2010Stratospheric Cooling and Tropospheric Warming
Dan, Success! Thank you, Bob
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CBDunkerson at 04:19 AM on 5 December 20102nd law of thermodynamics contradicts greenhouse theory
damorbel #277: "How so? A has only 10% absorption capacity, B has 75%. Now the absorption capacity is always equal to the emission capacity, after all the reflection part cannot emit as well as reflect, can it? So both objects have the same temperature, any difference would clearly break the 2nd Law of thermodynamics." I'm sorry, but what part of 75 units of energy is greater than 10 units of energy don't you understand? Yes, an object cannot emit more energy than it absorbs. Ergo, if the more reflective object is only absorbing 10 units of energy it can only emit 10 units of energy. Those 10 plus the 90 reflected equal the 100 total incoming and thus incoming and outgoing energy are in balance. Ditto the less reflective object except that it is absorbing and emitting 75 units of energy. 75 > 10. It has absorbed and is emitting more energy. Higher energy absorption and emissions equals higher temperature. For the 90% reflective object to be the same temperature it would have to be emitting the same 75 units of energy... which added to the 90 units reflected would be 165 units total... which runs afoul of the law of conservation of energy... an extra 65 units of energy can't just spontaneously appear from nothing. You seem to be arguing that absorption and emission are the same for all objects... rather than that they are the same for each object. That clearly isn't the case because an object can't absorb energy it has reflected away. Taking Tom's example of a theoretically 100% reflective object it is clear that it would absorb no energy... and thus would be at absolute zero. The more energy an object reflects the less it absorbs and the colder it is. -
Daniel Bailey at 04:06 AM on 5 December 2010Stratospheric Cooling and Tropospheric Warming
Re: Bob Guercio (137) 1. First type this symbol: < 2. Next, type: img width="500" src="http://image_url/" 3. Replace the URL in Double Quotes "" with the actual URL intended 4. A common error is to have an extra / at the end of the URL; this can be avoided by using the preview function Hope this helps! The Yooper -
Daniel Bailey at 03:55 AM on 5 December 20102009-2010 winter saw record cold spells
Re: Rob Painting (10) Here's one from January 7th, 2010
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Bob Guercio at 03:39 AM on 5 December 2010Stratospheric Cooling and Tropospheric Warming
Bob Moderator Response: Fixed. See the help on posting images; you need an html tag: img src= "url" width=no more than 500 inside the usual lt and gt brackets. I don't get it. Could you please put exactly what you typed inside quotes or brackets. Thank you, Bob -
Rob Honeycutt at 03:35 AM on 5 December 2010Renewable Baseload Energy
Camburn @ 344... "What this thread shows is the reluctance of people to address co2 emmissions with the tech that is available and proven." This is patently, and utterly false. Virtually everyone here who has posted has stated they believe that nuclear belongs as a solution to CO2. What people here are NOT willing to say is that it is the ONLY solution. Conversely, the the nuclear proponents have been completely unwilling to accept any of the positive aspects of renewables. As I stated previously nuclear does somethings very very well. Stable, level output. If we needed exactly that then nuclear would be the perfect solution. That is NOT what is required. That does not perfectly address electrical demand. I'm sorry if you can't see it but nuclear also has negatives that nuclear proponents like Peter Lang are unwilling or incapable of seeing. And, once again, the grid level storage solutions presented in Dana's original article apply equally well to mitigating the losses of nuclear spin reserve off-peak as it does to the intermittency of renewables. -
Bob Guercio at 03:30 AM on 5 December 2010Stratospheric Cooling and Tropospheric Warming
134.Sphaerica at 03:12 AM on 5 December, 2010 Bob, I actually think that once you sort it out, you can come up with a simple explanation. . Figuring what to leave out is the key to any simple model created for explanatory purposes, as you well know (and despite what the "it's not realistic" crowd moronically screams). I think that I understand what you are saying. Regarding your comment about realism, I doubt if these people have ever had even a basic Physics or Chemistry course. Bob -
Bibliovermis at 03:24 AM on 5 December 2010Renewable Baseload Energy
Another irony about people who push nuclear as The Solution is that many of them also argue that there is no problem; references to CAGW are a plain indicator. Lang has provided a good service here though. His posts have been a case study in how not to discuss a contentious topic. This was a thread about renewable baseload & how it could be achieved. Exhortations that such a feat is impossible belong aside those that heavier than air flight is impossible. -
Bob Lacatena at 03:22 AM on 5 December 2010The human fingerprint in the seasons
55 (Humanity Rules), I don't see what you see. I went through the review, and while there are frequent references to the terms "winter", "summer" and "season", they almost all have to do with data studied being limited to a particular season (e.g. MWP winters), not comparisons between the two. The only reference to a specific difference in the seasons has to do with stratospheric wind patterns, and even these were inferred from model runs, not observations. I find nothing at all in the review to support your claim. Alternately, the review also says this:...many of these solar-climate associations also seemed highly improbable simply on the basis of quantitative energetic considerations.
andRecent estimates suggest a radiative forcing drift associated with solar irradiance changes of 0.017 Wm-2 per decade (see section 2). In comparison, the current rate of increase in trace greenhouse gas radiative forcing is about 0.30 Wm-2 per decade (Hofmann et al., 2008).
So I'm not sure how anyone could make any observations on seasonal impacts of solar variations when there haven't been any. -
Bob Guercio at 03:21 AM on 5 December 2010Stratospheric Cooling and Tropospheric Warming
Hi All, I've tried to post an image but again I am not successful.
Could someone take care of this for me and then show me the exact code used for this image.
I was going to ask the question "The ozone layer is not at the top of the stratosphere so how does heating of the ozone layer cause the temperature to be the highest at the top?" But then I saw this image which shows the temperature increasing and then decreasing as you go up through the statosphere. This is what I would expect.
That said, how is the stratosphere defined. Apparently it is not simply simply defined by a negative lapse rate!
Bob
Moderator Response: Fixed. See the help on posting images; you need an html tag: img src= "url" width=no more than 500 inside the usual lt and gt brackets. -
Bob Lacatena at 03:12 AM on 5 December 2010Stratospheric Cooling and Tropospheric Warming
Bob, I actually think that once you sort it out, you can come up with a simple explanation. A lot of the complications can still be removed. The difficulty with anything like this lies primarily in removing relatively inconsequential complications. The reader probably does not need to know that the stratosphere is heated through UV and ozone creation, or what "optical thickness" means (that is a very confusing, obscure term that is meaningful to people that are familiar with it, but requires a paragraph just to explain, and so distracts and confuses the reader). Terms like "adiabatic lapse rate" and the 15 micron issue are similarly confusing details which do not really add anything to the heart of the explanation. A lot of things can be left out. Figuring what to leave out is the key to any simple model created for explanatory purposes, as you well know (and despite what the "it's not realistic" crowd moronically screams). The only factor that you really need to incorporate with what you have already written, IMO, is that energy is transferred at the molecular level via collision or emission/absorption, and in varying proportions depending on the density of the atmosphere. The main point is simply that energy can be absorbed one way but then surrendered in another, so that at equilibrium the total-radiation-in need not equal total-radiation-out in a particular band. As a result, the CO2 in the troposphere is more likely to absorb IR in that narrow CO2 band, but then passes it on through collisions to the abundant, non-emitting O2/N2, raising temperatures and somewhat "blocking" that band of radiation. Alternately, the CO2 in the more rarefied stratosphere is more often excited by collisions with the more abundant O2/N2, and emits the gained energy through radiation before it can pass it on through another collision. So CO2 prevents energy from escaping from the troposphere into the stratosphere in the CO2-IR bandwidth, and CO2 actively cools the stratosphere by emitting energy in the CO2-IR bandwidth. The only question left to clarify is relative amounts of these mechanisms (i.e. how much does stratospheric emission contribute to cooling, versus tropospheric "blocking"). I suspect that the latter is minor, at least as far as its influence on stratospheric temperatures (but I don't know). -
swieder at 03:12 AM on 5 December 2010Renewable Baseload Energy
Here are some more interesting links of actual projects/studies/companies in the field how to make renewable more reliable. - The first IEEE smart grid symposium - German company "energymeteo" - Australian company CSIRO - virtual power plant - RWE & Siemens effort: review article on VPP - VPP, microgrids, energy hubs: overview (semester thesis by R. Bühler from ETH Zürich, CH) To me it looks like the concept behind distributed energy production and virtual combination to be able to work on centralized offering for customers is gaining more and more attention and is leaving the concept/theory phase, entering in the demonstration/piloting phase around the globe. -
Riccardo at 03:06 AM on 5 December 2010The human fingerprint in the seasons
Alexandre to quote from the review linked by HumanityRules:There have been suggestions that 20th century global and hemispheric mean surface temperature variations are correlated to longer-term solar variations. Advanced statistical detection and attribution methodologies confirm that solar forcing contributed to the increase in global temperatures in the early part of the century but for the latter part of the 20th century they consistently find that using realistic variations, solar forcing played only a minor role in global warming, in agreement with the practically constant mean solar forcing since 1980.
The passing of time doesn't apper to help the "it's the sun" supporters. -
muoncounter at 03:06 AM on 5 December 20102009-2010 winter saw record cold spells
#11: "The image @10 is somewhat misleading" Indeed. This thread is about winter 2009-2010; the photo date puts it in winter 2010-2011. -
Philippe Chantreau at 03:04 AM on 5 December 2010A basic overview of Antarctic ice
"Since it appears to be statistically insignificant." I don't know how one can look at the data and come to that conclusion. Whatever analysis this assertion is based on is in error. The decline of global sea ice is statistically significant. -
muoncounter at 02:51 AM on 5 December 2010Positive feedback means runaway warming
#24: "I worry that our "clathrate gun" and associated ice age relics might be cocked and loaded, so to speak. " It is, as with many other questions of climate change, a question of rate of change. Thus we do not know if the loaded gun has birdshot or a deer slug. Archer 2007 is an excellent summary of methane hydrate and their climate change potential. The hydrate reservoir is so large that if 10% of the methane were released to the atmosphere within a few years, it would have an impact on the Earth’s radiation budget equivalent to a factor of 10 increase in atmospheric CO2. ... Fortunately, most of the hydrate reservoir seems insolated from the climate of the Earth’s surface, so that any melting response will take place on time scales of millennia or longer. Acoustic images of real-time methane releases as in this example are dramatic evidence that such melting is indeed occurring, albeit in isolated places. As summer Arctic sea ice continues to dwindle in the coming few years, 'science experiments' such as this will no doubt become more frequent and widespread. In my days in the offshore O&G exploration, hydrates were a well-known drilling hazard; punch a hole in one and you cause it to go unstable very quickly. These guys are going looking for them. Combine that plan with another series of avoidable mistakes such as those leading to the BP disaster and you have given your loaded gun to a bunch of drunk teenagers. Here is a long, but quite thorough 2008 Scripps Institute video on the subject. -
Riccardo at 02:35 AM on 5 December 2010The human fingerprint in the seasons
HumanityRules the two warming trends are both real and shown in the figure above. It's not clear to me why you say that the solar forcing influence on winter temperatures contradicts that the influence is larger in summer. -
Phil at 02:32 AM on 5 December 20102009-2010 winter saw record cold spells
The image @10 is somewhat misleading; note the "snow" in the English channel, North Sea and Irish Sea. The area where I live appears to be covered in snow, but there was none. Clouding the issue perhaps ? (Ouch, sorry) -
Daniel Bailey at 02:08 AM on 5 December 2010Positive feedback means runaway warming
Re: Leland Palmer (24) Recent evidence supporting the clathrate gun hypothesis exists:"Evidence that massive quantities of methane gas have been released from the sea floor during past ice ages has been reported. The discovery supports the hypothesis that huge releases of ocean methane contributed to the rapid warmings of the Earth that have ended past ice ages."
As reported in Reporting Climate Science .Com Free copy of the study available here. I agree with Ned in that, to the level of understanding we have currently, the possibility of a methane clathrate/hydrate release sufficient to trigger a hydrogen sulfide release and/or leading to a Venus-style runaway situation is remote. What is disturbing, however, is that such a possibility even exists. More disturbing is that future conditions may not be a good analog for anything in the paleo record other than the PETM. Without being able to establish an upper bound to the risk, we may find out that we we didn't know was more relevant than what we did. That should be of concern to all, as this is an experiment to be run once only. The Yooper -
swieder at 02:05 AM on 5 December 2010Renewable Baseload Energy
#344 I think there are many posts here contrasting what you said. More important: this thread is not about nuclear in any way. The question raised is the baseload capability of renewables, not the ability of nuclear to reduce CO2. Please. -
Camburn at 01:47 AM on 5 December 2010Renewable Baseload Energy
What this thread shows is the reluctance of people to address co2 emmissions with the tech that is available and proven. Nuclear should be being built in the US. It is not to any scale. While the rest of the worlds large economies are building nuclear, the US languishes in debate. The stupidity of doing nothing but arguing is enough to make a grown man moan and groan with frustration. -
Leland Palmer at 01:14 AM on 5 December 2010Positive feedback means runaway warming
Wow, thanks for the quick and thoughtful response. Any thoughtful person would be thankful to be wrong about such a scenario, of course. The fact that we are coming out of an ice age, and starting from a cooler starting point might not save us from such a scenario, though. Our methane hydrate deposits are in equilibrium at ice age temperatures. The speed at which we are introducing CO2 is absolutely unprecedented, so far as I know. Also, the forcing from fossil fuel use is entirely non-random, unlike most past naturally occurring events. So, our methane hydrates could be particularly susceptible to disruption, and have had no chance to gradually lose methane, and have it safely oxidized into CO2 and sequestered via the rock weathering cycle over many thousands of years. Yes, there were warmer periods in the past, but we may have gotten to those warmer periods in a safer manner, more gradually, allowing harmless oxidation of methane at reasonable rates. The permafrost decay positive feedback is a similar concern. If this permafrost loses its frozen plant matter to decay into CO2 and methane gradually, there is no problem. If the accumulated frozen plant matter from thousands of years of ice age conditions decays within a century, though, this might add to warming in an unprecedented manner. The yedoma and thermokarst of Siberia are a similar concern. These ice age accumulations of methane and methane hydrate could also be susceptible to anomalously rapid dissociation. The PETM is worrisome, but the event that really worries me is the End Permian. As you point out, the PETM was nasty, but the End Permian mass extinction was the big one, extinguishing on the order of 90 percent of species existing at that time. Direct intrusion of the Siberian Traps volcanism into methane hydrate deposits may have been necessary to cause that one, but we don't know this for sure, so far as I know. So, I worry that our "clathrate gun" and associated ice age relics might be cocked and loaded, so to speak. Some things that might save us, as you point out, are the logarithmic nature of the greenhouse effects from the various greenhouse gases, and the diminishing returns positive feedback phenomenon. Also in favor of stability are the endothermic nature of methane hydrate dissociation, and the Planck radiation feedback. One thing that really worries me is the unpredictable nature of positive feedback phenomena. I frankly doubt the ability of anyone to predict the outcome of such a complex interlocked series of positive and negative feedbacks. If anyone could do it, it would be someone like Hansen- and Hansen is worried, too. Another thing that worries me is that estimates of the total quantity of methane hydrates differ by at least an order of magnitude. The sun is a couple of percent hotter than it was during the PETM, but several percent hotter than during the End Permian, I think. If we take the End Permian event, and add in a more rapid triggering event, a buildup of ice age methane hydrates, and a sun that is five percent or so hotter, what do we end up with? -
Alexandre at 00:54 AM on 5 December 2010The human fingerprint in the seasons
HumanityRules #55 Very well spotted. All that's needed now is to find a solar variation that would justify quantitatively the observed recent warming. Any links on this one? OTOH, I think there's plenty of evidence about another known forcing that has risen during the last half a century. -
Rob Painting at 23:50 PM on 4 December 20102009-2010 winter saw record cold spells
Check out the cool satellite shot of snow blanketing the UK (from Science Daily).
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swieder at 23:42 PM on 4 December 2010Renewable Baseload Energy
Here is a more balanced and fact-based overview i found about how renewables are seen in Australia regarding baseload in the Parliamentary Library of the parliament of Australia. -
Bob Guercio at 23:11 PM on 4 December 2010Stratospheric Cooling and Tropospheric Warming
Tom, But more energy is coming into the earth than leaving. This applies to both the ground and deep space. My prevous remark regarding a distinction here was gratuitous. If we stabilized CO2 levels, this would continue for a few decades. Bob -
michael sweet at 23:08 PM on 4 December 2010Renewable Baseload Energy
My position on nuclear has shifted more negative due to Peter Langs postings. I am still agnostic since I know other people who think it is a good idea. If Peter's arguments are the best nuclear can do it is not worth much. I find Peter's posts to be riddled with inaccuracy and I now presume anything he says is factually incorrect unless another poster supports him. This thread and the "what should we do about renewables" thread both essentially devolved into Peter insulting everyone else after he came on. It is too bad, they were both good threads before Peter came on. -
Ned at 22:37 PM on 4 December 2010Positive feedback means runaway warming
Leland Palmer writes: How likely is all of this? You've written that very coherently, and it's not by any stretch of the imagination a "crackpot" scenario. But I would say it's very unlikely, even under a BAU emissions scenario. Lord knows I'm no expert on the PETM, but achieving that kind of CO2 pulse would seem to require burning more fossil carbon than would be projected even under an extreme scenario. And my understanding of the benthic methane hydrate issue is that it's likely to kick in only very slowly (on a global scale, ignoring local exceptions). The PETM was certainly nasty, and we wouldn't want to subject ourselves to anything like it. But it didn't lead to the kind of Venusian runaway warming you describe, despite involving much higher temperatures than AGW is likely to produce (remember that in addition to the large magnitude of the warming, the PETM was starting from a warmer point). Yes, the sun is hotter now, but the PETM-Holocene difference in TSI isn't that large (a couple of percent?). Perhaps most importantly, there have been other periods in the past (not just the PETM) when the planet was much hotter than today (think crocodiles and azolla blooms in the Arctic) and no Venusian runaway occurred. On very long timescales (tens of millions of years), the earth has been gradually cooling. We're going to be unwinding that process by at least a couple of degrees C in a geologically very short time ... but I think the dangers more involve disruption of our agricultural system, expensive and painful impacts from sea level rise, and loss of biodiversity (esp via ocean acidification). I don't think the Venusian runaway is remotely likely unless our descendants tried really hard to bring it about. (E.g., massive production and release of CFCs). Again, though, paleoclimate isn't really my area of expertise, so this is just one person's amateur understanding. -
HumanityRules at 22:22 PM on 4 December 2010The human fingerprint in the seasons
44 Albatross So fingerprint = correlation? Is that all? Wow. Anyway I managed to get side tracked onto solar variance. There's a huge review of it here. http://www.agci.org/dB/PDFs/10S1_LGray_SolarInfluencesCLimate.pdf There are numerous references to a link between solar variance and winter warming trends which seem to contradict "If global warming was driven by the sun, we should see summer warming faster than winter.". It looks like observational based correlations of solar cycle variance are better at identifying a winter warming trend than one in summer. There's plenty of interesting points in that review to get both sides of the argument excited. -
Rob Painting at 22:16 PM on 4 December 2010Ocean acidification isn't serious
Chris Shaker @17 Please search for 'Iron Fertilization' in this paper to see that iron is well recognized as a limiting factor in plankton growth Well aware of that thanks. Sorry, but "iron fertilization" is one of those ill-considered "engineering" ideas: Can ocean iron fertilization mitigate ocean acidification? " Here, using a global ocean carbon cycle model, we performed idealized ocean iron fertilization simulations to place an upper bound on the effect of iron fertilization on atmospheric CO2 and ocean acidification. Under the IPCC A2 CO2 emission scenario, at year 2100 the model simulates an atmospheric CO2 concentration of 965 ppm with the mean surface ocean pH 0.44 units less than its pre-industrial value of 8.18. A globally sustained ocean iron fertilization could not diminish CO2 concentrations below 833 ppm or reduce the mean surface ocean pH change to less than 0.38 units. This maximum of 0.06 unit mitigation in surface pH change by the end of this century is achieved at the cost of storing more anthropogenic CO2 in the ocean interior, furthering acidifying the deepocean. If the amount of net carbon storage in the deep ocean by iron fertilization produces an equivalent amount of emission credits, ocean iron fertilization further acidifies the deep ocean without conferring any chemical benefit to the surface ocean" -
Rob Painting at 21:58 PM on 4 December 2010Ocean acidification isn't serious
Chris Shaker, You have so many misconceptions about the topic, it's difficult to know where to start. The advanced version of Ocean Acidification should be out by years end and hopefully that clears up some of your confusion. Coral reefs - long term monitoring is showing a rise in bleaching events and coral death. Both acidification and ocean warming negatively impact coral reefs. Again, this is a topic for a later post but some reading: Caribbean Corals in Crisis: Record Thermal Stress, Bleaching, and Mortality in 2005 Worst coral death strikes at SE Asia - 19 October 2010 "Many reefs are dead or dying across the Indian Ocean and into the Coral Triangle following a bleaching event that extends from the Seychelles in the west to Sulawesi and the Philippines in the east and include reefs in Sri Lanka, Burma, Thailand, Malaysia, Singapore, and many sites in western and eastern Indonesia. “It is certainly the worst coral die-off we have seen since 1998. It may prove to be the worst such event known to science,” says Dr Andrew Baird of the ARC Centre of Excellence for Coral Reef Studies and James Cook Universities. “So far around 80 percent of Acropora colonies and 50 per cent of colonies from other species have died since the outbreak began in May this year.” -
Tom Curtis at 21:44 PM on 4 December 2010Stratospheric Cooling and Tropospheric Warming
Bob, my discussions have covered the steady state. However, I am also not sure how important a distinction that is in the stratosphere in that, not lying next to any oceans, and being a rarified gass, the time interval between perturbation and adjustment to steady state would be quite short. -
cjshaker at 21:21 PM on 4 December 2010Ocean acidification isn't serious
There is also a Wiki on Iron Fertilization of the Ocean http://en.wikipedia.org/wiki/Iron_fertilization "Perhaps the most dramatic support for Martin's hypothesis was seen in the aftermath of the 1991 eruption of Mount Pinatubo in the Philippines.[citation needed] Environmental scientist Andrew Watson analyzed global data from that eruption and calculated that it deposited approximately 40,000 tons of iron dust into the oceans worldwide. This single fertilization event generated an easily observed global decline in atmospheric CO2 and a parallel pulsed increase in oxygen levels.[7]" Chris Shaker -
cjshaker at 21:15 PM on 4 December 2010Ocean acidification isn't serious
Please search for 'Iron Fertilization' in this paper to see that iron is well recognized as a limiting factor in plankton growth. They are talking about using Iron to cause plankton blooms to sequester CO2 and drop it down to the ocean floor http://www.cephbase.org/refdb/pdf/8122.pdf That paper also seems to show that mortality rates for some sea creatures, such as mollusks, increase with CO2. Chris Shaker -
cjshaker at 21:04 PM on 4 December 2010Ocean acidification isn't serious
The paper I referenced, showing plankton growth limited by iron was from Nature "We conclude that Fe deficiency is limiting phytoplankton growth in these major-nutrient-rich waters." http://www.nature.com/nature/journal/v331/n6154/abs/331341a0.html Chris Shaker -
cjshaker at 21:00 PM on 4 December 2010Ocean acidification isn't serious
Your link to a nature article does not appear to work http://www.nature.com/nature/journal/v466/n7306/abs/nature09268.html%3Cbr%20/%3E Did you notice the paper I referenced, showing plankton growth limited by iron? Chris Shaker -
cjshaker at 20:57 PM on 4 December 2010Ocean acidification isn't serious
Rob Painting: Did you read the paper I referenced, showing increased biomass in coral with increased CO2? Did you read the paper I referenced, showing increased plankton growth with increased CO2? Are you offering me any peer reviewed papers proving the opposite? No. Chris Shaker -
Rob Painting at 20:48 PM on 4 December 2010Ocean acidification isn't serious
This paper leads one to believe that it is not as simple as the AGW believers want us to believe You're arguing a strawman there. Changes in seawater chemistry are anything but simple. Would we not expect the ocean equivalents of plants to also grow more as the CO2 increases as well, providing more food for sea life? No. Decreased carbonate concentrations in seawater, combined with acidification and ocean stratification affect the long-term viability of phytoplankton populations. For example: Global phytoplankton decline over the past century "Here we combine available ocean transparency measurements and in situ chlorophyll observations to estimate the time dependence of phytoplankton biomass at local, regional and global scales since 1899. We observe declines in eight out of ten ocean regions, and estimate a global rate of decline of ~1% of the global median per year. Our analyses further reveal interannual to decadal phytoplankton fluctuations superimposed on long-term trends. -
cjshaker at 20:10 PM on 4 December 2010Ocean acidification isn't serious
This paper leads one to believe that it is not as simple as the AGW believers want us to believe. Increased CO2 does seem to decrease CO3 in the lab, which is considered a limiting factor for coral growth. But, it also increases photosynthesis output, and actual coral growth in terms of biomass does not seem to suffer, and actually increases in some studies http://www.isse.ucar.edu/staff/kleypas/docs/PUBS/kleypas_langdon_icrs_2000.pdf More information http://scienceandpublicpolicy.org/images/stories/papers/originals/coral_co2_warming.pdf Are they trying to measure coral growth the wrong way when they concentrate on calcium carbonate measurements? Would we not expect the ocean equivalents of plants to also grow more as the CO2 increases as well, providing more food for sea life? Yes, plankton growth will be stimulated by increased CO2 levels, as long as other limiting factors do not come into play http://epic.awi.de/Publications/Tor2008b.pdf Another paper I scanned said that parts of the ocean are deficient in iron, which limits plankton growth http://www.nature.com/nature/journal/v331/n6154/abs/331341a0.html Plankton and algae will increase productivity as CO2 levels increase in seawater, they die, raining down on the sea floor, sinking more CO2. Chris Shaker -
Joe Blog at 20:09 PM on 4 December 2010Stratospheric Cooling and Tropospheric Warming
Bob Guercio at 07:45 I think Tom and Spaceman have covered your questions as well as i could have(truth is, most of my posts on this thread have been "trying" to convey the mechanisms alluded to by the radiative exchanges in that paper.) And the existence of the tropopause itself, is pretty convincing evidence that this is the main phenomena responsible for stratospheric cooling/energy loss. -
Bob Guercio at 19:36 PM on 4 December 2010Stratospheric Cooling and Tropospheric Warming
Tom, Just one more point. Do your discussions here cover the transient state, the steady state or both. We are in the transient state now because more energy is reaching the earth's surface than that which is leaving. Let's assume that we miraculously stabilized atmospheric CO2 concentration today. The temperature of the earth will continue to rise until the output energy from the earth equals the input energy. That would be the steady state. I'm not talking about energy coming in and out from beyond the thermosphere. I'm talking about the ground. I meant my blog to be strictly for the steady state. Bob -
Billhunter at 19:12 PM on 4 December 2010A basic overview of Antarctic ice
Albatross at 09:42 AM on 4 December, 2010 Hi Bill, "Umm, no. I'm afraid that you seem to have completely missed the point of that statistical analysis exercise. Anyhow, the graph @89 is the net result of all the changes/processes and it is showing a distinct downward trend in global sea ice since about 2001." I looked at your post #74 and did not see the test of statistical significance applied to global sea ice Albatross. Since it appears to be statistically insignificant it probably either is or very close to it.
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