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Comments 92151 to 92200:

92151. Tom Curtis at 10:47 AM on 18 March 2011
       What would a CO2-free atmosphere look like?
       TTT @73 and 74, the issue of the Earth's probable temperature with very low, or no CO2 is a critical issue with regard to climate sensitivity. If it is a fact that with no CO2, water vapour levels would fall sufficiently that the mean global temperature was -19 degrees C, or less, then the notion that climate sensitivity is 0.5 degrees per doubling of CO2, or even 1.5 degrees per doubling, are absurd. That might be a merely academic point. Where it not for one fact, there would be no way to independently test the consequences of very low CO2. But, as it happens, during at least two periods in the past the Earth had very low CO2. Consequently model experiments on very low CO2 can be tested against geological data from those events. What is becoming evident is that low climate sensitivities are inconsistent with the Earth entering a snow ball (or slush ball) state. And they are even more inconsistent with the Earth leaving such a state, in that without a strong greenhouse effect, the strong negative forcing of global ice cover cannot be overcome. This leaves aside the rhetorical issue, ie, the reason Lindzen concocted his figure. Lindzen asserts a low value for the temperature change with no CO2 to create in his audience a false impression that climate sensitivity is low. Giving a more accurate figure would have been counterproductive to his rhetoric. So perhaps your "fantasy figure" is better than Albatross's "fantasy figure" for you, but only if it is your intent to deceive.
92152. Charlie A at 10:44 AM on 18 March 2011
       Maximum and minimum monthly records in global temperature databases
       I was trying to discuss statements made in your article and in your comments. Such as the statement in your article that "This analysis undermines, yet again, many of the simplistic contrarian models e.g. that natural variability is driving warming," Please explain how your analysis relates to attribution of the detected warming. You refer back to your comment #46. "In other words, we must look to processes that warm or cool the globe to explain the excursions in Figures 2 and 3. The conventional wisdom is that (human induced) CO2 warming did not set in on a large scale until the 1970s, whereas warming earlier in the century was due to other (natural) variations. There is nothing explicit in the chart to upset that view." I agree with your observations about conventional wisdom, but was hoping for something in your analysis that actually supported that conventional wisdom rather than merely being consistent with it; or an analysis that merely failed to explicitly disprove the conventional wisdom.
92153. Albatross at 10:35 AM on 18 March 2011
       What would a CO2-free atmosphere look like?
       TTT, Instead of ROFL, you might want to try and engage in some actual science. And to be quite honest, your post @75 makes no sense whatsoever.
92154. Larry E at 10:28 AM on 18 March 2011
       Examining the impacts of ocean acidification
       Thanks for giving this important issue some exposure. I would like to add that data for pH or carbonate saturation that are global averages tell one story, but some areas are far more susceptible to these acidification effects than others. Here are some interesting references: McNeil BI, Matear RJ (2008). Southern Ocean acidification: A tipping point at 450-ppm atmospheric CO2. Proceedings of the National Academy of Sciences (105:48; p.18860). http://www.pnas.org/cgi/content/abstract/105/48/18860 Bernie D, Lowe J, Tyrrell T, Legge O (2010). Influence of mitigation policy on ocean acidification. Geophys. Res. Lett. (37:15; p.L15704). http://dx.doi.org/10.1029/2010GL043181 DO - 10.1029/2010GL043181 McNeil & Matear (2008) show in what a short term timeframe significant ecological impacts can be anticipated in high latitude waters, with Southern Ocean "wintertime aragonite undersaturation ... projected to occur by the year 2030 and no later than 2038. Some prominent calcifying plankton, in particular the Pteropod species Limacina helicina, have important veliger larval development during winter and will have to experience detrimental carbonate conditions much earlier than previously thought, with possible deleterious flow-on impacts for the wider Southern Ocean marine ecosystem." And later, "Our results show wintertime aragonite undersaturation to potentially begin once atmospheric CO2 concentration reaches 450 ppm, which is the year 2030 using the IPCC IS92a scenario (Figs. 3 and 4). It must be emphasized, however, that the timeframe for atmospheric CO2 to reach 450 ppm could be earlier or later depending on the trajectory of future CO2 emissions. ... Early aragonite undersaturation is of particular concern for the zooplankton species comprising Pteropods, which form aragonite shells. Southern Ocean Pteropods comprise up to one-quarter of total zooplankton biomass in the Ross Sea (13), Weddell Sea (14), and East Antarctica (15), can sometimes displace krill as the dominant zooplankton (16), and dominate carbonate export fluxes south of the Antarctic Polar Front (17), and even organic carbon export (18)." Troubling to me is not only the ecosystem implication, but also that the Southern Ocean is a major carbon sink, and shell-building zooplankton is an important part of that. Bernie et al. (2010) deals with averaged global effects, comparing onset and severity of acdification problems to climate models and climate change mitigation scenarios. It notes that the Arctic will undergo changes faster than the paper predicts, that effects in coastal areas and at depth around the world are highly variable and not examined. The paper estimates that if with "aggressive mitigation" CO2 emissions peak in 2016 and decline at 5% per year to a low long-term value, the global average pH decline could be limited to 8.02, "roughly a doubling of current acidfication." However, without mitigation by 2100 the level would be 7.67 to 7.81. The Bernie et al. paper notes limitations of similar previous studies and that this is the first to study "acidification under a range of emissions scenarios and analyze what aspects ... have most impact on future acidification. The key feature of this study is the explicit relation of future pH to aspects of global climate change mitigation policy."
92155. Tom Curtis at 10:17 AM on 18 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       L.J.Ryan, I forgot in my post 615 to mention the equalities only apply in the equilibrium condition. To explore the non-equilibrium condition, let us assume time steps equal to the average time it takes light to cross the depth of the box once. We use the average time because the photons may be at different angles, and hence have different path lengths. Let us also assume that 100 photons enter the box in each time step. We set the initial time step,0, to the time photons first start entering the box, but before they strike the back wall of the box. In that case, the number of photons in each of A, B, C, and D for progressive time steps are: Following Phil's suggestion, I have modeled this on a spreadsheet, using the following formulars: Column B2 and subsequent: 100, column C2: 0, Column C3 and subsequent is the sum of columns B and D for the preceding row. Column's D and E2: 0; and for columns D and E3 and subsequent, 0.5 times the value of column C in the preceding row. The first twelve steps show as follows: STEP A B C D 0 100 0 0 0 1 100 100 0 0 2 100 100 50 50 3 100 150 50 50 4 100 150 75 75 5 100 175 75 75 6 100 175 87.5 87.5 7 100 187.5 87.5 87.5 8 100 187.5 93.75 93.75 9 100 193.75 93.75 93.75 10 100 193.75 96.875 96.875 11 100 196.875 96.875 96.875 12 100 196.875 98.4375 98.4375 Clearly there is a problem for the spreadsheet that it allows fractional photons. What would happen in the real case is that occasionally 99 photons would leave the box, and occasionally 101, but typically 100 would leave the box. Furthermore, the mean value of photons leaving the box once the equilibrium state is reached would be 100. So, ignoring the quirk of fractional values, it is plain the system quickly approaches the state described in my 615. Do you have any problems with that?
92156. Albatross at 10:15 AM on 18 March 2011
       Maize harvest to shrink under Global Warming
       Rob @31, I agree with your position on this. This is, IMHO, an interesting example of a "skeptics" who is in denial. Johnd is continuing to make unsubstantiated assertions. These findings are no doubt inconvenient to him--I know he'll deny that, but that much is clear from his posts and efforts to obfuscate. What he fails to realise is that hand waiving and talking through his hat does not further his case. If someone elects to dismiss the findings of a paper published in Nature (or any reputable journal for that matter), it is incumbent on them to bring substantial evidence and science to the table in order to be taken seriously. From the start of this thread he has been making comments clearly without having bothered to read the paper, and he was called on that. Being a true "skeptic" does not mean that one has to contort in order to dismiss the findings of papers which do not support your position. "Skeptics" are permitted to agree with some of the literature on AGW without compromising their position-- in fact, doing so from time-to-time would work towards improving their credibility. To stay on topic, these findings are also consistent with those of Samson et al. (2011), who found that Africa is going to be one of the countries which is most negatively affected by AGW. We are doing them no favours if we decide to bury our heads in the sand and ignore these troubling findings. We have all been warned of the possible perils ahead.
92157. TimTheToolMan at 09:54 AM on 18 March 2011
       What would a CO2-free atmosphere look like?
       Yeah, rofl Albatross with your insistance that your fantasy figure is better then my fantasy figure. " The biosphere is a fully coupled and interactive system, you cannot ignore feedbacks." The biosphere is full of carbon and hence carbon dioxide.
92158. Phil at 09:48 AM on 18 March 2011
       Sea level rise: coming to a place near you
       rhjames @5 I'm guessing that Scandanavia, like Scotland, is experiencing rebound after the last Glaciation. The potentially bad news for piloot is that the extent of Glaciation in the UK means that the lower half is sinking due to the same effect. The same could be true of the Netherlands, since it lies at a similar latitude.
92159. rhjames at 09:39 AM on 18 March 2011
       Sea level rise: coming to a place near you
       piloot - I tried to check sea level change in your area. If the Scandanavian countries nearby are any indication, you have little to worry about. Sea levels have dropped about 250mm over the past 130 years. It looks like there are other bigger influences than climate change out there.
       Moderator Response:

       [DB] Rates of isostatic rebound experienced thus far will be dwarfed by the rates of SLR to get to the 1 meter SLR expected by 2100 (1,000mm over 90 years). Unless Hansen is right about the nonlinearity of ice sheet loss to come, in which case that rate jumps to 5,000mm over 90 years.

       The current mapping tool does not reflect impacts from isostatic rebound; some future iteration will (it is being looked at).

92160. johnd at 09:37 AM on 18 March 2011
       Maize harvest to shrink under Global Warming
       Rob Painting at 09:24 AM, the purpose of the field trials is to identify how each variety performs under field conditions. They have no way of knowing this unless they conduct the trials. What happens in a laboratory enclosure is often quite distant from what occurs in the field. Of all the people that have posted on this thread, surely it was incumbent upon yourself to bring such understanding to the discussion.
92161. piloot at 09:29 AM on 18 March 2011
       Sea level rise: coming to a place near you
       The situation for the Netherlands doesn't seem fair or realistic in this comparison. Half of the country is already below sea level and man-made that way, surrounded by dikes and (wind)mills, completed with an enormous irrigation network to constantly pump the water out and to protect it against storms from the North Sea or floodings from meltwater out of the Rhine. If the map would have a setting for nil change, it would still show half the country flooded (like the less than 1 meter change now), which just isn't the case (I'm typing this from 4 meter below sea level as we speak and I'm still dry). A storm (usually combined with moon setting) in 2006 caused an almost 5 meter sea level rise above the average level in Holland, but the dikes still held (in contrast to 1953 which killed 1863 people, causing a huge delta plan with new dikes and barriers to prevent that form ever happening). The whole system is constantly maintained, monitored, fortified and updated, in contrast to poor countries with low lying areas. I'm not saying sea level rise won't be a problem, but for Holland the consequences won't be like portrayed in the map.
92162. scaddenp at 09:25 AM on 18 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Tom, I really like this. Same idea as Science of Doom example but much simpler.
92163. Rob Painting at 09:24 AM on 18 March 2011
       Maize harvest to shrink under Global Warming
       John D - Whilst we don't know how many different varieties were trialled or how each performed. The idea that the trials would incorporate any old rubbish maize is nonsense. Simple invention on your part. And quite frankly odd, why would an organization carrying out such trials, use varieties that were ill-suited to the prevailing conditions?. The CYMMT was set up in the 1970's, they've been breeding for maize drought tolerance ever since. Selective breeding is an ongoing process. I expect the private seed companies to have agricultural expertise too. Charlie A - planting and harvesting times are not optional. These are determined by local conditions.
92164. rhjames at 09:19 AM on 18 March 2011
       Sea level rise: coming to a place near you
       This is all very interesting, but I have a problem with justifying the comment "currently we're on track to reach 1m." As I live in Sydney, and Sydney is mentioned, I checked the Fort Denison data, which shows no sea level rise over the past few years, and about 8mm over the past 25 years. 1998 was the hottest year over the past 160 years, and this year so far has seen a temperature drop. Now, I may well accept that sea levels will rise, but I can't say we're "on track" to reach 1m increase by 2090. We need to see some temperature increase, and/or sea level increase.
92165. johnd at 08:59 AM on 18 March 2011
       Maize harvest to shrink under Global Warming
       michael sweet at 06:08 AM, the most disappointing form of hand waving is that when the only knowledge that can be offered to a discussion is "it's been peer reviewed". That carries the implication that the peer review process is perfect, and that each peer reviewed paper encapsulates all the knowledge there is to know on the subject. If you carefully read back through this thread, you will find that most of the comments questioning the paper are not on the integrity of the study process, but rather whether the findings provide anything new or are even relevant to the real world. Even if you have little appreciation of how or why field trials such as those that provided the base data for the study are conducted, you surely must appreciate the fact that not all new varieties being trialled perform up to expectations. The difference between what this study did by including the results of all the varieties trialled, and what the plant breeders would have done, is that the plant breeders would have selected the results from those varieties that met or exceeded their expectations and having done so, worked to refine or further develop the desired traits before releasing them for commercial use. You can be fairly certain that when such new varieties are being released and promoted, that it will be the data for each specific variety that will be used to illustrate how each variety will perform under different conditions,and certainly not what this study projects. It is largely irrelevant to the real world and provides virtually nothing new to those whose purpose is to actually produce the food required. Given the rate at which new varieties are produced, the study is likely many steps back from where plant breeders would currently be, certainly well off the pace. The one point I do question about how the study was conducted is about why they used rainfall data other than what normally would be collected at the immediate trial site. It will be unknown if any bias is present unless rainfall had been measured at the trial site, in which case, that is the data that should have been used. If you can provide some insight as to whether my concerns are valid or not, then I would certainly be interested to listen. The use of rainfall data collected at other than the immediate trial sites has on occasion been sufficient reason for the findings of such trials to fail passing the peer review process here in Australia.
92166. Phil at 08:11 AM on 18 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       L.J.Ryan C will equal D. This scenario is very similar to the spreadsheet I posted here. You can model Tom's box using a 5 column spreadsheet thus; In row 1 type A, blank, B, C, D (to represent the quantities on Tom's diagram) In row 3 type 100, 0, =A3+B3, =C3*0.5, =C3*0.5 In row 4 type 100, =D3, =A4+B4, =C4*0.5, =C4*0.5 Copy row 4 into the next 30 lines of the table. You will find equilibrium reached after about 17 iterations and that Tom's calculations match in every detail. To check the conservation of energy you must let the accumulated energy in the box dissipate. To do this copy row 30 into 31 and set cell A31 to 0. Copy row 31 to the next 15 or so cells. If you sum column A and D (don't forget, column D represents Tom's arrow C) you will find they are equal.
92167. Kiwiiano at 08:04 AM on 18 March 2011
       Sea level rise: coming to a place near you
       Oi! You've listed Christchurch in NZ as liable for flooding with a rise in sea level. Don't forget a good chunk of Auckland, Tauranga, Napier, Wellington, Nelson, Greymouth, Dunedin and Invercargill. About the only main center that will escape it will be Hamilton. And Lawrence.
       Moderator Response: [DB] Christchurch was chosen as it had recently been in the news due to the earthquake there. All coastal cities in NZ (as you note) and throughout the world will have to deal with sea level rise at some point.
92168. shoyemore at 08:00 AM on 18 March 2011
       Maximum and minimum monthly records in global temperature databases
       Charlie A #49, You seem to want to discuss matters which you would be better to raise elsewhere, such as Early Century Warming Your points about this post are answered adequately in #46. If you re-read the post carefully, you will find it also deals with these matters, such as in the paragraph after Figure 1.
92169. funglestrumpet at 07:42 AM on 18 March 2011
       Sea level rise: coming to a place near you
       Articles like this could be separated into a general information on Climate Change section that the general public would, if directed there, go to in preference to a lot of the other articles on this site, which are often esoteric in nature and beyond a lot of us, me included. This article would do wonders for public involvement in the issue if they were to become worried that the value of their property was going to suffer. Let's face it, property prices are going to tumble long before the waves are licking at the front door. To paraphrase the wise man quote abov: The Tides, They Are A Changin'.
92170. Chris G at 07:27 AM on 18 March 2011
       Examining the impacts of ocean acidification
       CB, Regarding use of the term dying, IDK, but the P/T extinction event is often referred to as The Great Dying, and no one takes it to mean the planet became totally dead. No matter. Otherwise, yeah. Someone asked me if I thought climate change would lead to man becoming extinct. My reply was something to the effect that we are like cockroaches; it is very difficult to kill all of us. But, there may not be nearly as many of us afterward.
92171. Charlie A at 07:13 AM on 18 March 2011
       Maximum and minimum monthly records in global temperature databases
       A minor note ... in the "Further Reading" you should add a hyphen to int-res in the 1st URL. 1. "Random incidence is a hypothesis, not an assumption...... certainly rejected by the data." Agreed. Of course, one can simply look at the global temperature times series and come to this same qualitative conclusion in a much easier manner. 2. "...... Hence the excursions shown on the charts must be concluded to be due to extrinsic factors". This is where you start to lose me. A lot depends upon your definition of extrinsic factors. Are you saying that your charts show, that over the timeframe you plotted, that natural variation has been excluded as a reasonable hypothesis? 3. "A second (composite) hypothesis that temperatures changes up to mid-century are due to naturally occurring factors, and changes thereafter are due to human-induced factors, is also not rejected by these data." Agreed. But that an equally valid statement is "A second hypothesis that temperature up to mid-1900 are due to human induced factors and changes thereafter are due to naturally occurring factors are not rejected by these data". In other words, your data can be said to not reject ANY hypothesis relating to attribution. To put it rather crudely, I have a hypothesis that the temperature variations are due to the number of visitors to Niagra Falls. As you put it "There is nothing explicit in the chart to upset that view." While that hypothesis is rather outlandish, hopefully it shows the logical fallacy of claiming that the data and the analysis in any way supports your second (composite) hypothesis that "that temperatures changes up to mid-century are due to naturally occurring factors, and changes thereafter are due to human-induced factors". Yes, your data is consistent with your hypotheses. But your data is also consistent with the hypothesis that global temperatures are influenced by the annual visitor count at Niagra Falls. For both the Niagra Falls hypothesis and for you second hypothesis, additional data and analysis is required.
92172. scaddenp at 07:08 AM on 18 March 2011
       CO2 lags temperature
       Also, if you think paleoclimate is more or less unconstrained, invent anything, have a look at Zeebe et al 2009 on difficulties with PETM. (Doesnt begin to address the cause of carbon release but deals with other issues). Needless to say my colleagues think they have a possible solution to the conundrum posed...
92173. les at 06:48 AM on 18 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       622 Ryan.. Yes, and I'm pointing out that, really - they are (all) integrals. That may be a problem of notation rather then violation of a fundamental physical property.
92174. Rob Honeycutt at 06:39 AM on 18 March 2011
       Skeptical Science nominated for Climate Change Communicator of the Year
       Philippe... I would define "athleticism" on WUWT as "working hard to put on a good show." They definitely slog through the science to find (and often distort) bits and pieces to fit their agenda. They work very hard at it.
92175. Tshane3000 at 06:36 AM on 18 March 2011
       One of the best climate change ads I've seen
       Right on Sphaerica. @ClimateWatcher, Science is rarely ever an easy sell--unless, and this is only maybe--when it's about cute, fuzzy koala bears going extinct. That's because science is nuanced and complicated--and scientists aren't marketing experts. Marketing nuance is tough! Also, there is no dumbed-down echo chamber in science, as there is among (pardon me, but both these labels are true:) corrupt or ignorant conservatives who want business as usual only because it's in their interest (at least, financially--certainly not ecologically, as their planet and descendants are at risk). Myths and lies and disinformation--climate change denial--keep spinning round and round in the media because most people just *won't* do the hard work of ferreting out truth. But finding truth is what science does so well--and it's not as easy as mere sloganeering and speaking in sound bytes. Truth is the realm of science. Profit is the realm of greed, power and survival. Both are possible in a sustainable world, but sustainability balances profit with people and planet. Sustainable development must be managed by those who see the world with a far wider, more compassionate and future-oriented lens than those bouncing in the echo chamber, and digging like piggies after easy money in greasy dirt. One of the great things about the scientific method is that it welcomes legitimate, well-reasoned challenges. That is built into the system, so it continually evolves to better and better understand both the "why" and "how" of nature. True science is an ever self-perfecting truth machine that keeps on giving to the human race--far more than any organization, religion or other human-created system, physical, mental, philosophical or other. It crosses and merges and encompasses all those realms, and more. If conservatives want to challenge the science, go get climate science degrees and do it! It just hasn't happened. Conservatives who have science degrees by and large make too many mistakes in their work to be considered legitimate. It seems clear that their political beliefs mostly drive their science, whereas legitimate science must always drive politics when appropriate--as it is when a threat hangs over humanity as large as climate change. Why don't conservatives get climate science degrees? It's too much work, compared to just dumping your money in oil stocks and sit back sipping tequila on a beach! Greed is a far easier sell than altruism. Hence the $ billions Big Oil makes, and the pennies the environmental movement garners. These lies about huge profits to be made in green energy are just silly--unless you also want to work twice as hard as anyone else to make the profits. If we didn't have to, nobody would do it. Oil and coal are going, "sure things." (Which is why the industry is fighting so hard to keep it up. But even they admit global warming is happening! They just don't fully want to blame themselves and give up the cash cow so easily.) By contrast, developing green energy worldwide is the hardest work the population of Earth may ever do. The canaries in the coalmine (literally) are singing--and people are dying because of it--every day, more than in most industries. (Yet another reason to get rid of dirty, polluting coal.) Best get to the good, green work ASAP! Thank God someone finally came up with effective marketing for it.
92176. y-not at 06:15 AM on 18 March 2011
       Those who contribute the least greenhouse gases will be most impacted by climate change
       I note that Bangladesh has been mentioned several times in the posts as seriously at risk due to AGW above but looking at the graphics Bangalesh seems to be coming off not to badly compared to many others. Does the CDVI take into account sea level rise, and if it it does what degree of sea level rise/timeframe is it based on? I cannot access original paper.
       Moderator Response:

       [DB] The mapping simulations specifically take into account sea level rise, but make no projections as to how much sea level rise occurs when. Here's Bangladesh (remember the scale you're looking at):

       

       It's interesting to note the river bed channel cut into the continental shelf by the river during glacial maximums.

92177. andthorne at 06:14 AM on 18 March 2011
       Those who contribute the least greenhouse gases will be most impacted by climate change
       Not when you consider methane emissions. What goes up as methane comes down as formaldehyde and the United States of America is one of the countries impacted greatly by it, according to a 1995 study by the Smithsonian University and Harvard scientists. Andrea Silverthorne
92178. michael sweet at 06:08 AM on 18 March 2011
       Maize harvest to shrink under Global Warming
       Johnd and Charlie, Perhaps the two of you are not familiar with the peer review process. This paper was published in Nature, one of the most respected journals in science. The peer reviewers have concluded that simple issues like you have raised are not germane to this discussion. If you have a problem with that you need to produce actual analysis of data. Idle hand waving and saying "I doubt it" for no particular reason is not an argument against a paper published in Nature. Provide links to data supporting your extraordinary claims or put in the effort to analyze the data yourself.
92179. L.J. Ryan at 06:06 AM on 18 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       les@621 Like I said C can equal A, but C cannot equal D.
92180. GFW at 06:05 AM on 18 March 2011
       And so castles made of sand fall in the sea, eventually
       Unfortunately, the idea of buying future coastline property doesn't work. Once the melt accelerates enough to cause the current coastline to indefensible, sea level rise is likely to be a multi-century process, with a "new" coastline every decade or so.
92181. Chris G at 06:02 AM on 18 March 2011
       Examining the impacts of ocean acidification
       Mike G, Thanks for the explanation. I recall some back of the envelope calculations that we could correct for extra CO2 by adding carbonate compounds to the ocean. They calculated that if we were to mine all of the cliffs of Dover, grind it up, and disperse it through the world's oceans, that would neutralise the extra CO2, but I can't recall whether that was at present levels of CO2 or a doubling, or what. In any case, no, that doesn't happen in nature, at least not at the rate required to accommodate the rate we are adding CO2. Ah, found it. Not exactly what I remembered, but the point remains. http://www.realclimate.org/index.php/archives/2009/10/an-open-letter-to-steve-levitt/ Gavin's comment #9 Gavin's link is broken, but likely is related to Ocean acidification due to increasing atmospheric carbon dioxide Page 37 "To counteract the changes in acidity caused by today’s ocean uptake of roughly 2 Gt C per year (IPCC 2001) would require roughly 20 Gt CaCO3 per year (Caldeira & Rau 2000), which, for a limestone layer 100 m thick, would require the removal of roughly 60 km2 each year." "Furthermore, limestone does not dissolve in surface waters, so additional processing, and energy, would be needed (Kheshgi 1995; Rau & Caldeira 1999)." and "Although the vast amounts of carbonate minerals needed may make this approach infeasible at the scale required to mitigate global changes in ocean chemistry, this approach is widely used by salt-water aquarists to promote coral growth in fish tanks. Thus, it might be possible to use alkalinity addition to save specific coral reefs (Rau & Caldeira 2002), but such ideas have never been tested in situ and therefore must be regarded as speculative." Speculative indeed.
92182. les at 05:44 AM on 18 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       "till they do." - oops, sorry should be "till the sum of Ds = A"... Or do you think it's possible that a significant number of photons will bounce around the box for ever without leaving?
92183. DSL at 05:43 AM on 18 March 2011
       Peer reviewed impacts of global warming
       "The scientific community almost unanimously agrees Earth is in a warming period as part of the natural cycle." Nope. That's the thing: according to identified "natural" cycles, we should be heading for an ice age. We're not. During the last solar minimum, average global temp increased. Shorter-term natural cycles--El Nino/La Nina--do not add heat/energy to the atmosphere; they move it around. The scientific community almost unanimously agrees that Earth is warming due to increased CO2, CH4, and H20 lengthening the path of infrared radiation as it exits the system. It's like a detour because of road construction: same number of cars entering and exiting the system, but more time is spent driving (and perhaps dropping by the Arctic Ice store on the way to melt a few kilos). As for No. 2, the more serious debate is between those who have various opinions on feedback mechanisms (particularly albedo in the form of land use, clouds, snow cover, etc.). That CO2 is a path lengthener is hardly seriously debated anymore (except here, by a handful). So as the drivers drive home via the detour, how many wrecks will they cause, causing more detours? As Arctic sea ice is diminished, how does that affect planetary albedo? As the temp rises, how much more water vapor (a GHG) does that put into the troposphere? No. 3: It seems that way. Life is persistent, but the speed of environmental change can't exceed the speed of evolution, or life will suffer. Our ability to adapt--as a species--is wicked. But there are seven billion of us living in a pretty complicated and sketchy system of food, water, shelter, and energy distribution. Minor disruptions, like the Japanese earthquake, cause thousands of deaths. It's easy to say that increased warmth will lengthen the growing season, but the person saying it usually hasn't taken into account everything else happening simultaneously: migrations, economic and political considerations, disease adaptation, insect (both as pollinator and pest) adaptation, changes in precipitation patterns and intensities, and all the interconnections between these elements. Your friend is right: Oil is good -- how we use oil . . . well that's another question.
92184. Alexandre at 05:41 AM on 18 March 2011
       Peer reviewed impacts of global warming
       Gairzo #94 Asking questions is good. I don't think you summed up well the current scientific understanding about GW. About your conclusion #1: there are many natural cycles known to science. None of them explain the recent warming (over the last half a century or so). For mor detail, you can see these posts here (among others): It's a natural cycle It's the sun So, the scientific consensus and the evidence do not point to natural causes. I think that kind of covers your #2 too. Your #3, which refers to this post specifically, is basically correct, although I'd elaborate more on the "planetary survival" bit. Let's say we'd have a lot of negative impacts on both human societies and ecosystems. for a more comprehensive picture ov the available evidence, there the Scientific Guide to GW Skepticism too. I hope this gives you a starting point. Feel free to ask. Oh, and welcome to SkS.
92185. les at 05:41 AM on 18 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       619 Ryan - hint: the walls are reflective. All the photons which do D (i.e. don't escape when they hit the front window) will bounce around (lets say B') till they hit the window again and are either C' or D', then B''/C''/D'', B'''/C'''/D''' etc. till they do.
92186. Bob Lacatena at 05:39 AM on 18 March 2011
       One of the best climate change ads I've seen
       6, ClimateWatcher, And it has to be sold because: 1) Many (most?) people are too shortsighted to look or think beyond their most immediate needs 2) There is a lot of money being spent on the foolish idea that climate change is not a problem. 3) There is a horde of people who have, for various reasons, fallen for the denial meme, and so tout that particular line even when they aren't getting a big check from the fossil fuel industry. The quiet implication that climate change needs to be sold because it's not real is as invalid as it is offensive. Regardless of the reason for the "sale," people need to prompted into waking up and doing something, by a variety of means, and the fact that this particular effort is annoying to deniers tells me that it is an effective tool.
92187. Alexandre at 05:07 AM on 18 March 2011
       Those who contribute the least greenhouse gases will be most impacted by climate change
       It's a striking picture. I understood IEA data include only fossil fuel combustion (someone correct me if I'm wrong). For greater accuracy, I think the CO2 emission figures should include all emission sources, and all GHG. I don't think the overall picture would change much, but there could be some notable local differences. After all, fossil fuels are only about half of the picture.
92188. Gairzo at 04:59 AM on 18 March 2011
       Peer reviewed impacts of global warming
       I'm just a screenwriter living in Burbank and am having the debate with what are obviously right-wing, John Locke-ish, extreme deniers. I made the mistake of saying there wasn't a peer reviewed study denying global warning. So these climate change deniers verbally spanked me and sent me to a couple websites. After a short review, it was clear few of these sites denied warming was occurring but blamed it on the natural cycle, the sun etc. Please try and educate me on the general conclusions I reach from the twenty or so articles studies, charts, I've read--in other words please tell me if my conclusions have any merit: 1.) The scientific community almost unanimously agrees Earth is in a warming period as part of the natural cycle. 2.) The debate is between those who believe the spikes in temps, ice melting, oceans rising, etc.--the "negatives" seen in the last 150 years--are due to human activity, and those who claim human activity cannot possibly affect such forces that manifest over hundreds of thousands of years. 3.) From what I read, the "negative" studies far outweigh the "positive" studies and our planetary survival could well be in question if we don't act now. My friend sent me an e-mail extolling the virtues of the free market and the horrible economic impact transitioning to alternative energies would be. He ended the e-mail in big red letters...OIL IS GOOD. I don't think he'd be convinced if penguins moved next door. I won't try. I just want to know if a non-science guy like me was generally reading the data accurately. Forgive the intrusion on your discussion, just though I'd ask.
       Moderator Response: [Daniel Bailey] Let me first start off by saying (in my best Ed McMahon imitation): "Welcome to Skeptical Science!" Second, you're not intruding: you're a guest here and guests get treated as valued persons (until some outwear their welcome then they get the ol' Heave-Ho!). Third (before we get to the main act), you have the right of it. Some will never be convinced of Christ's 2nd Coming unless they can stick a finger in His side... With the opening fanfare done, let's dig in, shall we?

       There is an immense amount of reference material discussed here and it can be a bit difficult at first to find an answer to your questions. That's why we recommend that Newcomers, Start Here and then learn The Big Picture.

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92189. Philippe Chantreau at 04:56 AM on 18 March 2011
       Skeptical Science nominated for Climate Change Communicator of the Year
       My vote is in, no doubt as to who my favorite are :-) Keep up the good work John. Rob, the "athleticism" at WUWT is really questionable. One has to peruse through that pathetic thread in which they slap each other on the back after some guy verified that CO2 does not deposit at -70 degrees in Earth' atmosphere. This, of course after repeated attempts by some who knew better to make the general population of the site understand the phase diagram. It's painful to watch such collective idiocy in action. These are the same people who go on accusing scientists of fraud when they clearly don't have the means to even begin to understand what the scientists are doing. If there is any "athleticism" at WUWT, it's barely at 8th grade level.
92190. Charlie A at 04:43 AM on 18 March 2011
       One of the best climate change ads I've seen
       It would be even more effective if one of the polar bears was in danger of being sucked into the whirlpool.
92191. L.J. Ryan at 04:41 AM on 18 March 2011
       2nd law of thermodynamics contradicts greenhouse theory
       Tom Curtis@615 1. A = C ok 2. C can not equal D without violating the 2nd law. Otherwise you have doubled your light/energy with a mirror and a filter. Light can not brighten due to it's own reflection. If your box was fully enclosed such all surfaces are reflective save two small aperture. One aperture to receive light the second to radiate light, do you really think the light/energy will increase beyond it's input? Now change your perfectly reflective interior to one with an emissivity of 1 (black body). Do you believe C will be grater then A. Again no. Black body emission represent the maximum conferred energy for light input. Therefore, a surface with emissivity less then one will NEVER radiate more then it's black body equivalent...regardless of it's own reflection or it' own re-radiation (back radiation).
92192. shoyemore at 04:34 AM on 18 March 2011
       Maximum and minimum monthly records in global temperature databases
       Charlie A #47, You can read some of the "Further Reading" which provide further detail of the "1/n model" for a random incidence of records. Random incidence is a hypothesis, not an assumption. As a hypothesis, it is certainly rejected by the data. Hence the excursions shown on the charts must be concluded to be due to extrinsic factors. A second (composite) hypothesis that temperatures changes up to mid-century are due to naturally occurring factors, and changes thereafter are due to human-induced factors, is also not rejected by these data. In that usual scientific sense, that is support. Confirming what we already know is quite boring, but most scientific experiments and analyses end up that way. However, these data may say something about the "cooling" that allegedly took place from the mid 1940s to mid 1970s, when greenhouse gas heating kicked in. These data seem to say that 1945 to 1956 was rather a slowdown in the warming trend (no coldest months noted, but several months that ranked in the top 10, other than 1). It also seems to date the end-of-century warming to the end of the 1950s, rather than the 1970s. Those are the only departures from the conventional picture presented by the temperature data analysis, and warrant further examination.
92193. Charlie A at 04:31 AM on 18 March 2011
       Maize harvest to shrink under Global Warming
       The problem with simplistic extrapolations such as "Roughly 65% of present maize-growing areas in Africa would xperience yield losses for 1 °C of warming under optimal rain-fed management," is that it assumes farmers are dumb. Farmers in different regions and different climates plant and harvest at different times of the year. It is unreasonable to assume that planting and harvesting times will not change.
92194. johnd at 04:29 AM on 18 March 2011
       Examining the impacts of ocean acidification
       dhogaza at 03:40 AM, "warming winters" is the equivalent of " declining alkalinity". "Hotter winters" is a more appropriate comparison for ocean acidification.
92195. johnd at 04:18 AM on 18 March 2011
       Maize harvest to shrink under Global Warming
       Rob Painting at 18:27 PM, whilst you might see some take-home points, I see only bring-along points which is what my very first comment on this thread indicated. Regarding your comment of uncultivated areas, perhaps further study of the information able to be extracted from the maps might lead to such areas being better described as areas beyond those already considered marginal. We must see this study for what it is. The authors are not those people who conducted the original trials. They have been able to utilise some data yielded by the trials but I expect that other data would have been considered propriety by the trial managers, and as such their, the trial operators, take-home points likely to be somewhat different to what this study could allow. The reason this is likely comes with understanding what trials such as these set out to achieve. The development of new varieties is an ongoing process as various traits are sought to be refined or developed. Developing varieties that allow cultivation to be extended into areas now considered unsuitable or marginal is as much an objective as increasing yields under existing conditions, and it appears that the former was one of the primary objectives of the original trials. Not all varieties live up to expectations when field trialled, some show negative responses, others none, others positive responses to varying degrees. Whilst we don't know how many different varieties were trialled or how each performed, what is indicated in this study is that the data is all in, in other words, the data includes the failures and the successes. This is where those conducting the original trials will most likely be taking home something different to what this study allows. They will have identified, and quantified, those varieties that responded positively to the trial conditions. It will be those such varieties that extend the ongoing development in plant genetics that allow productivity to keep pace, or even out-pace change as it occurs.
92196. Mike G at 04:08 AM on 18 March 2011
       Examining the impacts of ocean acidification
       Ken, you're forgetting the significance of the biological pump and the the effects of depth/temperature on CO2 solubility. Unlike heat, the pH and dissolved inorganic carbon patterns aren't determined by the mixing depth or diffusion rates.
92197. Mike G at 04:03 AM on 18 March 2011
       Examining the impacts of ocean acidification
       @8 WheelsOC- In oceanography, alkalinity and pH are two distinct parameters. Alkalinity is essentially the measure of the buffering capacity of seawater. Usually in the case of ocean acidification we're talking specifically about carbonate alkalinity, which measures the amount of buffering provided by carbonate and bicarbonate ions. Rest assured that when oceanographers are talking about the acidity of the sea, we use pH just like everyone else. The confusion comes from the fact that seawater has a pH>7, so it can be described as alkaline- though that term is unrelated to the measure of alkalinity. As the seas take up CO2, they become less alkaline, but alkalinity isn't directly affected. Confusing enough? ;) FWIW, while we are concerned about the reduction in pH, the real concern is the impact that that reduction in pH has on CaCO3 saturation. Even under pH below 7.8 many calcifiers do just fine so long as carbonate concentrations are maintained. Unfortunately, that works well in an aquarium but doesn't happen in nature.
92198. pbjamm at 04:00 AM on 18 March 2011
       Republicans to Repeal Laws of Physics
       Tom Curtis @177 "2) Attempting to place the burden of proof entirely on the opposing theory" This is the root of many a skeptic argument tactic. They reject the evidence as inadequate or fraudulent thus forcing the burden back onto the supporters of the AGW theory. Since this rejection is based entirely on ideology it makes it impossible to shift back. You can present evidence and facts til you are blue in the face and all the skeptics need do is deny them as facts. It is an unwinable struggle and a very unscientific attitude.
92199. Andy Skuce at 03:45 AM on 18 March 2011
       Those who contribute the least greenhouse gases will be most impacted by climate change
       One of the limitations of applying cost-benefit analysis to climate change is because the costs and "benefits" (ie, avoiding or reducing negative impacts) accrue to different people or groups of people. Seen from the point of view of a poor Bangladeshi girl, having a wealthy westerner pay more for their energy in exchange for a slightly reduced chance of he grandfather's farm becoming submerged looks like a good deal, regardless of the discount rate or the damage probability function. And vice versa, unfortunately.
92200. dhogaza at 03:40 AM on 18 March 2011
       Examining the impacts of ocean acidification
       "ocean acidification" is no more wrong than discussing "warming winters".

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