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Comments 48601 to 48650:

48601. Don9000 at 04:54 AM on 19 February 2013
       Geologic Time and Climate Change Science
       

       Glad to provide it, Tom. Stephen Jay Gould wrote a number of natural history essays that touch on deep time, sometimes directly, sometimes less so. In one that I recall, he pointed out that early on in the evolution of vertebrates there was a great deal of "experimentation" on just how many digits a limb should have. He cited multiple examples of animals with more than the usual five to make the point that evolution spun out many different options at various points in deep time, and I believe he also pointed out that the fossil record is so fragmentary that we really have no idea just how rich life was way back when.

       In the same way we have a hard time reconstructing climate conditions from way back then, we also don't have a good sense of what complete ecosystems looked like even a few thousand years ago. We only need consider some very recent extinctions or near extinctions to grasp that modern humans inhabit a landscape that, despite our perceptions to the contrary, is dramatically different from what it was only a couple hundred years ago. The two things I'm thinking of are the American chestnut and the Passenger Pigeon. Both were ubiquitous in the eastern third of the US and their absence has altered the physical landscape we inhabit in ways we will probably never fully understand. I suspect global warming, even if we prevent its most catastrophic impacts, will, two hundred years hence, have effected staggering changes to the places we call home.

       This will be a great cultural loss, amongst other things. When I travel in England, I often have the sense that the landscape I'm seeing, with its fields, hedgerows, and woodlots and their accompanying array of species, is still relatively similar to what Shakespeare or William the Conqueror would have seen. I doubt people in two hundred years will be able to maintain that same connection. In other words, global warming, like indiscriminate hunting or the introduction of a new virulent disease, acts like an accelerant on the natural processes of change that go on all the time.

48602. Christopher Gyles at 04:35 AM on 19 February 2013
       Geologic Time and Climate Change Science
       

       Twain essay here

48603. Bob Lacatena at 03:54 AM on 19 February 2013
       It's the sun
       

       I love that when such a graph clarifies a scientific point, it's propaganda, but when it appears to prove that all of the world's climate sceintists are engaged in a gigantic hoax-conspiracy, it's laudable citizen science.

       And these people don't recognize their irrational, internal bias.

48604. Bob Loblaw at 03:51 AM on 19 February 2013
       It's the sun
       

       ...and following up on what I asked in #1062:

       If you provide the request % changes, then can you also tell me what the % change is for the following?

       a) 32F to 14F?

       b) 14F to 32F?

       c) 41F to 23F?

       d) 23F to 41 F?

       
       ...and if they are not the same as the % for the examples in degrees C, can you explain why?

48605. Bob Loblaw at 03:43 AM on 19 February 2013
       It's the sun
       

       fmbatchelor @1060:

       OK. If what you say is true, then can you tell what the percentage change in temperature is when the absolute change is:
       

       a) 0C to -10 C
       

       b) -10C to 0C?
       

       c) +5C to -5C?
       

       d) -5C to +5C?
       

       Or perhaps you'd like to reword your claim?
       

48606. Tom Curtis at 03:10 AM on 19 February 2013
       Geologic Time and Climate Change Science
       

       Don, I enjoyed the analogy.  Putting it in terms of the figure above:

       The last section (10) is the duration since the extinction of the dinosaurs.

       The black line (1 pixel wide) represents the time since humans diversified from our common ancestors with Chimpanzees.

       Homo sapiens has been around for 4% of the final pixel.

       Civilization has been around for 0.2% of the final pixel. 

       And the time since the industrial revolution represents the last 0.003% of the final pixel.

48607. Tom Curtis at 02:59 AM on 19 February 2013
       It's the sun
       

       fmbatchelor @1060, really?  So when I carefully scale change in ppmv of CO2  concentration and change in temperature in degrees C such that a the predicted transient climate responce in temperature for a given change in concentration matches the temperature scale, that would constitute propoganda in your book?  Where as if I scaled them so that a change of 1 ppmv in CO2 concentration (0.25%) matches a change in temperature of 0.72 K (0.25%) that would not constitute propoganda, even though the later change in temperature is only predicted for an approx 90 ppmv change in concentration for the transient response?  Frankly, I consider your suggestion absurd, and it is not one applied (to my knowledge) in any science.  Indeed it could not be.

       As it happens, the graph I take it you are criticizing has the scale it does because that is the scale chosen by advocates of the sun being the cause of the current warming to make their case.  They now face a dilemma.  If that scale is correct, than the lack of correlation after 1980 refutes their claim.  If, on the ohter hand, the scale is incorrect, then they have established no relation between solar activity and temperature to begin with.

48608. Tom Curtis at 02:45 AM on 19 February 2013
       We're heading into an ice age
       

       Kevin @297, it is a shame that after the long wait you could only come up with a link to an article that I had previously linked to (@ 293, second link).  It would have been nice if you had come up with something new.  In this case the something new is a report of a new excavation of a late iron age, or possibly early Roman, vinyard (or possibly asparagus garden) in Hertfordshire.

       It should be noted that viticulture probably survived in England throughout the dark ages, and certainly survived in England throughout the Little Ice Age, only ceasing after WWI, due to the commercial inability to compete with cheap French imports.  It restarted in England following WWII.  Given that, why do you regard the presence of vinyards in Roman Enland as proof it was warmer at that time than now rather than simply proof that it was not colder than the LIA (when grapes were also grown in England to make commercial wines)?

       Also of interest is this study of modern viticulture in Baltic coastal regions.  It shows this interesting map which shows commercial viticulture in Denmark and Sweden:

       

       Again, given the northern distribution of commercial viticulture, which includes not only commerical vinyards in Denmark and Sweden, but vinyards being developed with the intention of becoming commercial in Scotland), why do you regard the presence of vinyards in more southerly regions in England as proof that the Roman Warm Period or Medieval Warm Period was warmer than current temperatures?

       
       And finally, why do you regard evidence that it was warmer then than now in just one region of the world (evidence you have so far failed to produce) as proof that it was warmer than globally rather then now?  

48609. Dikran Marsupial at 02:38 AM on 19 February 2013
       We're heading into an ice age
       

       Cheers Andy, very interesting, the differing standards of acceptable evidence in archaeology and climatology is very evident (of course this is inevitable and not an indication of a problem with archaeology)!

48610. Don9000 at 02:37 AM on 19 February 2013
       Geologic Time and Climate Change Science
       

       One of the most creative takes on this subject is Mark Twain's short satirical essay "Was the Earth Made for Man?" Twain wrote this piece around 1900 when Darwin's theory of evolution had come under attack from scientists who, unaware of the processes of atomic decay that keep the earth's core nice and toasty warm, argued that our planet could not possibly be old enough to allow for all the time Darwin's theory seemed to require. One of the chief scientists in this debate was Lord Kelvin. Along with others, Kelvin believed thermodynamic realities limited the earth's age to 100 million years or less and he spent a lot of his intellectual energy in his later years making this point.

       In his essay, Twain engages in the debate and uses the Eiffel Tower instead of a human's outstretched arms to indicate the span of time involved, and likens our time on the planet to "the skin of paint on the pinnacle knob at its summit." He has a great time pointing out that the poor deluded oyster, who showed up 19 million years into the scheme, might well be excused for thinking that the earth was created for him, but goes on to explain that the oyster was just one of many things created for man as part of God's great plan. It really is quite good.

       The essay was suppressed more or less willingly by Twain during his lifetime and was not published until 1938, when it appeared in Letters from the Earth, a collection of Twain's most irreverent writings. Incidentally, the letters referenced in the title are purported to have been written by Satan about what he has learned about Man, God's great creation, to his best buddies Michael and Gabriel back in heaven and include a letter about how the Ark had to turn back to recover a housefly in order to preserve, not exactly for humanity's benefit, typhoid germs.

       Anyway, tracking down a copy likely involves purchasing this book. Of course, the book is well worth the price, as it also contains things like the delightfully witty "Extracts from Eve's Autobiography," which is found in a series of similar spoofs under the heading "Papers of the Adam Family." In Eve's autobiography, we learn that Adam was the first scientist, and his first important discovery was that water flowed downhill. The book is thankfully readily available in a paperback reprint published by HarperPerennial.

        

48611. fmbatchelor at 02:31 AM on 19 February 2013
       It's the sun
       

       Whenever you see a chart that has unlike elements, i.e. W/m2 and temp C, on the Y axis superimposed ( -snip-)  and they are not expressed in terms of percentage of change then you are witnessing propaganda.

       Moderator Response: [DB] All-caps converted to bold, per the Comments Policy (which you need to read and internalize before commenting further). Inflammatory tone snipped.
48612. Andy Skuce at 02:13 AM on 19 February 2013
       We're heading into an ice age
       

       There is a free-access, text-only version of that paper available here. 

48613. Dikran Marsupial at 01:53 AM on 19 February 2013
       We're heading into an ice age
       

       Kevin, thanks for the link, it is a shame that the article is paywalled - it looks interesting (see also Toms comment).  Please do take on board my comments in the previous post.  We are happy to discuss science here, but you will get a much better reception if you make your points in a measured scientific, rather than a confrontational hubristic manner, especially as your previous comments suggest a lack of understanding of some important issues. 

48614. Kevin8233 at 01:33 AM on 19 February 2013
       We're heading into an ice age
       

       http://antiquity.ac.uk/ant/075/Ant0750745.htm

        

       Try this source for Roman Optimal Wine production n UK.

48615. meb58 at 00:55 AM on 19 February 2013
       Increasing CO2 has little to no effect
       

       I did not read this entire thread, so forgive my question.

       There was a discussion above about co2 sequestration.  I understand that the ocean's ability to 'buffer' additional co2 can be helpful at first blush.  But buffering mechanisms, to my way of thinking, are trade-offs if you like.  From my own botany and soil science background I understand that the chemical equation will 'buffer' in the other direction as well if conditions permit.  Doesn't the buffered co2 bother us?  I don't see it as a long term benefit; if we stop introducing co2 into the air today, the level can drop to a point where some of the co2 is re-released into the atmosphere...or is my science off?

48616. meb58 at 00:38 AM on 19 February 2013
       Increasing CO2 has little to no effect
       

       Regarding post # 64 by Stephen Baines:

       
       I asked a question about the law of conservation in a different thread and rceived some very interesting and compelling - to me - answers from Tom Curtis and Bob Loblaw.  They were clear and very helpful!

       Philosophically, I think it is important to be skeptical AND curious because the two fundamentally drive knowledge.  The two above mentioned men have been extremely helpful in presenting science as I remembered it, but with much more fidelity.

       I can only add here, questioning the limits our predictive powers, is that mother nature freely associates.  I trust the science and I consider models as useful tools to help point to a condition that is possibly very harmful to our future.  I cannot ignore, however, what I see...and for me it is sobering. 

48617. Tom Curtis at 00:33 AM on 19 February 2013
       There is no such thing as climate change denial
       

       MohammedY @18, for the hard at reading, the 'consensus of evidence' is "...many different measurements pointing to a single, consistent conclusion".   Of course, you already knew that.  You just could not resist the temptation to pretend that pointing out that the term 'concensus of evidence' is a metaphore, and and pretending that represents a substantive comment.  It is as if you wish that the term being metaphorical will make the evidence vanish.

48618. MohamedY at 00:08 AM on 19 February 2013
       There is no such thing as climate change denial
       

       I stopped reading when I reached the phrase "consensus of evidence". There is no such thing. The dictionary defines the word as "agreement in the judgment or opinion reached by a group as a whole". It involves people. So, what is consensus of evidence? Is it BS?

48619. meb58 at 23:37 PM on 18 February 2013
       No alternative to atmospheric CO2 draw-down
       

       To all thank you!  Bob Loblaw, thank you for pointing me in the appropriate direction.  I'll continue with a few uestions elsewhere. 

       Great community here!  I appreciate the help.

48620. meher engineer at 18:57 PM on 18 February 2013
       Analysis of Greenland Ice Cores May Provide Glimpse into Climate's Future
       

        

       @2 Martin, Eric Stieg, who wrote about the Eemian results at Real Climate on 23 Jan 2013, was asked the question you ask by John S @ Comment7. wrote " Air content data mostly. From the paper:

       'Before surface melt began between 128.5 and 126.7 kyr BP, the air content at the depositional site had a stable level of 85 ml kg−1 compared to the present level of 97.5 ml kg−1. When corrected for changing local summer insolation, the air content difference suggests a surface elevation at the depositional site 540 ± 300 m higher at the onset of the Eemian (128 kyr BP) than the surface elevation at NEEM today.'

       The paper goes on to discuss the corrections for ice flow, which are significant, because the ice at the bottom flowed from a site that was higher. So the actual elevation change they estimate is about 200 m (with a big plus/minus of 350 m!). -eric" in reply. 

48621. gpwayne at 17:32 PM on 18 February 2013
       2013 SkS Weekly News Roundup #7
       

       @IDunno (2)

       As Chomsky has pointed out, it is illegal in America, for the CEO or other employees of a publically quoted company to do anything other than to try to maximise the stock value of their company, and thus profit to shareholders. This then, is their agenda.

       You're quite right, but there is another way of looking at the same requirement, and one that suggests a different strategy regarding climate change. If it could be argued that, by their inactions, board officers or other responsible employees had been negligent in respect to environmental threats to the business, those same employees could find themselves on the wrong end of lawsuits launched by investors whose stock value and dividends had deteriorated.

       Business as usual may produce short term profits, but investors (particularly institutional ones like pension funds) will often take a longer view. I have long believed that the commercial world will have to come to terms with the reality of climate change, not because of science, but because otherwise they may fall foul of the same laws and definitions of responsibility you have quoted. In a litigious country like the US, there will be no end of lawyers seeking redress when profits start to tumble in keeping with share values, and it is for this reason I've advocated more focus on business activism and less on the regrettably unproductive governmental lobbying.

48622. Tom Curtis at 17:06 PM on 18 February 2013
       A Glimpse at Our Possible Future Climate, Best to Worst Case Scenarios
       

       Old Mole @37, the graphs show the difference in global mean surface temperature (GMST) from that estimated for 1750 for each year from 1900 onward.  That is, each point ploted shows for a given year, the GMST for that year minus the GMST for 1750; but showing that does not say anything about the range of the x-axis. 

48623. Old Mole at 15:42 PM on 18 February 2013
       A Glimpse at Our Possible Future Climate, Best to Worst Case Scenarios
       

       Pardon me, but is there some reason for one axis of figures 4, 5 and 6 to be labeled "Global Surface Warming since 1750" and the other axis starting in 1900?

48624. Tom Curtis at 12:57 PM on 18 February 2013
       A Glimpse at Our Possible Future Climate, Best to Worst Case Scenarios
       

       Icararus @34, the most appropriate climate sensitivity value to use is a complex issue, and depends both on time scale and the draw down rate of CO2.  As has repeatedly been shown by David Archer and other scientists, the initial increase of CO2 conentration due to increased emissions will largely be absorbed by the ocean on a time scale of 100-300 years.  After that draw down, approximately 20-30% of the initial CO2 increase will remain in the atmosphere, and will remain for a very long time (> 10,000 years).  There are two important points from this.  

       First, for up to a hundred years after the increase in emissions, the most relevant climate response is the Transient Climate Response.  If we increase CO2 concentration to about 1000 ppmv by the end of this century, we will experience the transient response to that, or about 3.65 C

       As time progresses, the surface will tend to the equilibrium response, but over the same time period the CO2 concentration will fall rapidly on about the same time scale.  What will be experienced in a hundred years or so, assuming we effectively cease emissions before then, will be (approx) the equilibrium response to a quarter of the peak CO2 concentration.  For our 1000 ppmv scenario, we will experience the equilibrium responce to an increase of 460 ppmv (ie, preindustrial plus one quarter of the increase above preindustrial), or just over 2 degrees C.

       As further time progresses, the full Earth System responce to the smaller long term increase will be experience, ie, something in the order of  3.55 C.  Unfortunately the temperature increase of that magnitude will be with us for a period at least equivalent to the entire history of human civilization todate.

       This scenario is no panacea.  There is much devil in the detail.  For example, should the time to the equilibrium response be shorter, we can expect a large temperature peak before the temperature declines with the initial decline in CO2 concentration.  If a high proportion of initial emissions are in the form of Methane, there will also be a large initial spike in temperature prior to the Methane decomposing into CO2 and water vapour.  Further, this scenario assumes a near total cessation of CO2 emissions, something that is not guarentted given that about 20% of emissions come from agriculture, and that there may be significant additional emissions in the form of feedbacks. 

       If you are interested, I have a spreadsheet showing indicative short and long term responses to various estimates of fossil fuel availability.

48625. chriskoz at 12:49 PM on 18 February 2013
       2013 SkS Weekly News Roundup #7
       

       Agnostic,

       I agree. It's known that mainstream climate scientists tend to eer on the side of caution and Meinshausen 2009 is no exception. For example Gavin has mildly criticised this paper for omitting the effects of CH₄. However,  Meinshausen did omit it on purpose, because the findings of Shakhova, no matter how alarming, cannot be decisively quantified and Meinshausenwanted the decisive quantification in order to speculate the FF industry future.

       However that's not my point. My point is, that with such excellent standing of Meinshausen 2009 almost four years now, even the most hardcore deniers silently accepting its math, anyone who continues to finance FF industries is simply irrational nutter.

48626. Riduna at 11:30 AM on 18 February 2013
       2013 SkS Weekly News Roundup #7
       

       Sorry, I know such things are not supposed to be said ..... but

       Even the most influential science papers underestimate the consequences of continued fossil fuel burning because modeling fails to address the contentious issue of carbon feedback released from thawing permafrost and clathrate, particularly on and under the Siberian continental shelf.  It is extraordinary that the findings and warnings of Shakhova, Semiletov and others are played down, dismissed or simply ignored.  Is this folly the result of a realisation that carbon emissions from these sources make a 2°C limit on global warming impossible, a 3°C limit unlikely and a 5-6°C increase by 2100 a possibility?

48627. mikeh1 at 10:14 AM on 18 February 2013
       There is no such thing as climate change denial
       

       Good to see that John's article has been reprinted in the The Age and is also currently the lead story in the Google News science section.

48628. Tom Curtis at 09:31 AM on 18 February 2013
       No alternative to atmospheric CO2 draw-down
       

       meb58 @30, mass is converved, but the atmosphere is not a closed system.  To better understand the relationship, consider the following chart of changes in O2 and CO2 concentratration between 1990 and 2000:

       

       (Source:  IPCC TAR, discussed in greater detail here.)

       The essential points are that after the combustion of fossil fuels, ocean and land uptake of CO2, and outgassing of O2 from the ocean, there is an increase of 15 ppmv of CO2, and a decrease of 33 ppmv of O2.  CO2 is heavier than O2, with a molar mass of 44 g/mole compared to 32 for O2.  The difference, due to the carbon atom, would represent an increase in atmospheric mass if the only change in concentration were due to combustion.  That is because the carbon was not part of the atmosphere before combustion.  Of course, combustion is not the only process, so the net change is proportional to ((15 * 44) - (33 * 32))/44, or a reduction of 9 times the molar mass of CO2 for every mole of CO2 added to the atmosphere.  That represents a reduction in mass of  19.2 Gigatonnes of mass for every 1 ppmv increase in CO2 concentration.  As the mass of the atmosphere is 5.137 Petatonnes (= 10^15), however, that represents less than 4 ten thousandths of one percent of the atmosphere's total mass.

       You will have noticed that there is not a 1/1 ratio between expected decrease in O2 and expected increase in CO2 in the above chart.  That, as previously mentioned is because of the combustion of hydrogen in hydrocarbons.  As previously mentioned (and again by Phillipe), this H2O precipitates out of the atmosphere, and does not add to atmospheric mass.  The total H2O in the atmosphere is increasing, but that is because of increased temperatures and is largely controlled by the temperature.

       The increase in H2O due to increased temperatures probably exceeds the loss due to combustion of fossil fuels, but only be a small margin as H2O is light (molar mass = 18 g/mole).  It does indeed increase the release of latent energy via precipitation which is a factor in changes in extreme weather events.  It also reduces the lapse rate (a negative feedback) and increases the greenhouse effect of water vapour (a stronger positive feecback).  Whether that adds up to "bang" is for you to decide, but overall it certainly makes the prospects for the future less inviting.

48629. dana1981 at 09:21 AM on 18 February 2013
       A Glimpse at Our Possible Future Climate, Best to Worst Case Scenarios
       

       Icarus @34 - yes, when I say equilibrium sensitivity, I refer to Charney fast-feedback sensitivity.  If you look at longer timescales, the picture is bleaker.  However, you never know what's going to happen in the future.  If we keep climate change in the manageable range this century, maybe we'll eventually be able to come up with a viable technology to extract and sequester CO2 from the atmosphere, in which case the longer timescale feedbacks could be avoided.  It's hard enough to project what's going to happen in the next century, so I tend to not try to go much beyond that.

       Composer @32 - 2°C above pre-industrial would put us outside the range of climate variation over the past million years or so, at least.  That's another good reason to try really hard not to pass that threshold.

48630. Icarus at 08:00 AM on 18 February 2013
       A Glimpse at Our Possible Future Climate, Best to Worst Case Scenarios
       

       Just to follow up on the comments about what should perhaps be called the Charney or fast feedback climate sensitivity (which I believe Dana is using in this excellent article) vs. the full 'Earth system sensitivity', Hansen derives the following from palaeoclimate studies:

       Fast feedback climate sensitivity is 0.75 ± 0.125°C/W/m² (3°C per doubling)

       Climate sensitivity including slow albedo feedback is 1.5°C/W/m² (6°C per doubling)

       Climate sensitivity including slow albedo feedback & non-CO2 GHGs is 2°C/W/m² (8°C per doubling)

       Climate sensitivity including all feedbacks between Holocene & ice-free state is ~2.4°C/W/m² (9.5°C per doubling).

       Hansen & Sato 2011

        

       The full feedbacks would take hundreds (thousands?) of years to be fully realised but studies find that we're going to see them already making a substantial impact within this century.  Just using the fast feedback climate sensitivity is understating the scale of the problem, I think.  If the timescales of longer term feedbacks are uncertain, that's all the more reason to make sure they're not forgotten in our eagerness to quantify the scale and timing of global warming.  Not a criticism of this article at all, just an observation.

48631. Jose_X at 06:04 AM on 18 February 2013
       There is no such thing as climate change denial
       

       >> The reason there's a consensus of scientists is because there's a consensus of evidence. But for some reason, none of the contrarians wanted to engage with that part (I can't imagine why not).
       
       In case you really didn't imagine why not, I do imagine at least this much:
       
       They generally are not scientists, so they don't read the research papers and frequently wouldn't understand good evidence and conclusions from bad ones. The evidence they "know" are overviews from various websites that use simplified arguments and very frequently cherry pick the data to help build out the narrative being sold.

       Understandably, led astray to see a limited and misleading portion of the elephant, many get angry and think climate scientists are doofs and/or dishonest in failing to see what "is" there.

48632. martin3818 at 05:58 AM on 18 February 2013
       Analysis of Greenland Ice Cores May Provide Glimpse into Climate's Future
       

       How so you determine the ice's altitude when it melted?

48633. idunno at 05:33 AM on 18 February 2013
       2013 SkS Weekly News Roundup #7
       

       I am also struck by the "Most Influential Paper" story; I was already vaguely familiar with the math through McKibben's work.

       It does seem to me that there is some hope for help here from a not-so obvious source: Wall Street. It seems to me that there are some pretty sound reasons for questioning the stock valuations of many energy-sector companies, based on this math.

       As Chomsky has pointed out, it is illegal in America, for the CEO or other employees of a publically quoted company to do anything other than to try to maximise the stock value of their company, and thus profit to shareholders. This then, is their agenda.

       I increasingly suspect that it is quite difficult for investors, getting their information from the WSJ, the FT or Forbes, inter-alia, to actually get full information on the risks asscociated with their investments in the energy sector. It is certainly the case, in my opinion, that the little of the WSJ's journalism that I have seen on the subject of energy and climate does them no credit, and does their readers no favours.

        In the political and economic climate that we now inhabit, I am beginning to suspect that ultimately, the markets will decide.

        

48634. william5331 at 05:24 AM on 18 February 2013
       Analysis of Greenland Ice Cores May Provide Glimpse into Climate's Future
       

       On the other hand, CO₂ levels are much higher now than during the Eemian so perhaps we will have melting of the West Antarctic ice sheet and much more of Greeland than during the Eemian.

48635. Rob Painting at 05:03 AM on 18 February 2013
       Ocean acidification: Some Winners, Many Losers
       

       Eric - It shouldn't surprise you to learn that Matt Ridley is wrong. The oceans are well saturated with calcium ions, so they are not a consideration. The concentration of calcium ions dissolved into the oceans only changes on geological timescales (typically millions of years) - hence the shift between aragonite and calcite seas over these long periods.

       It seems for many marine life the concentration (activity) of carbonate ions is the key because carbonate ions serve as one of the building blocks of the calcium carbonate (chalk) shell/skeleton. One of the reactions that takes place when extra CO2 is dissolved into the oceans is:

       

       Seawater currently favours the left-hand side of that equation, so adding CO2 to the oceans is actually decreasing the activity of carbonate ions, which in turn makes shell-building ever more energetically expensive. Decrease the carbonate ion concentration sufficiently (calcium carbonate undersaturation) and we end up with seawater that is physically corrosive to marine calcifiers.

       This corrosiveness is already occurring in the waters of the American Pacific Northwest where oyster larvae are now largely unable to survive in the wild, because they dissolve (Barton [2012]). The Antarctic is also seeing highly corrosive surface water too. See the photo below of a pteropod (sea butterfly) which was caught (alive) several years ago: 

       

48636. Eric Grimsrud at 02:50 AM on 18 February 2013
       Ocean acidification: Some Winners, Many Losers
       

       Sorry, I meant to say  because" average concentration of Ca++ in the oceans is much HIGHER than the sum of all carbonate, bicarbonate, and carbonic acid concentrations."  Thus according to Ridley, increasing the latter three would assist in CaCO3 formation.  

       (as we also know, of course, increased acidity serves to decrease the conc of carbonate ion relative to bicarbonate and carbonic acid - thus working against CaCO3 (s) formation -  an important point not mentioned by Ridley).

48637. Eric Grimsrud at 02:42 AM on 18 February 2013
       Ocean acidification: Some Winners, Many Losers
       

        

       I have a question.  I have heard that the oceans are under saturated by CaCO3 because the average concentration of Ca++ in the oceans is much lower than the sum of all carbonate, bicarbonate, and carbonic acid concentrations.  However,  when concerned with the solubility of the CaCO3 shells of living organisms, I would expect that the more relevant question is - is the sea water in the immediate vicinity of these living species saturated with respect to CaCO3?   If so, one would observe a gradient of Ca++ concentration as one moves from the region of shelled species out towards the depths am remote regions of the oceans.  Certainly such measurements have been made.    

        

       Note that Matt Ridley has suggested that increased atmospheric CO2 levels will actually facilitate the growth of CaCO3 shells (in his misnamed book, Realistic Optimist) - an argument that has meaning only if the sea water in the vicinity of shelled critters is not saturated w.r.t. CaCO3.   

        

       Any insight on this point would be apprecited.

        

48638. Bob Loblaw at 02:36 AM on 18 February 2013
       No alternative to atmospheric CO2 draw-down
       

       meb58:

       Note that this discussion of how increasing CO₂ cause changes in climate is starting to get off-topic for this thread. If you wish to continue some of these discussions, it would be a good idea to look for a more appropriate thread. Look through the View All Arguments link (beside the thermometer bulb at the top left section of page) to find places that discuss many topics. Any comments you place on any topic you find there will show up on the Comments page that everyone can access using the link in the menu bar under the main header, so it will be seen.

48639. Bob Loblaw at 02:28 AM on 18 February 2013
       No alternative to atmospheric CO2 draw-down
       

       Meb58@ 30: " What prevents that extra heat from escaping into space faster?"

       
       In essense, it does escape faster. A hotter atmosphere will lose energy faster, via increased emission of infrared (IR) radiation, but the followup to that is the question "at what point is a new balance reached?" A new balance is nto reached instantaneously - it takes time. If you want to think of it in a stepwise fashion, the steps are:

       a) energy, as sunlight, is absorbed by the earth-atmosphere system, mostly at the surface (but don't worry about that for now).

       b) energy is lost to space, from the earth and atmosphere, by IR radiation.

       c)  the earth-atmosphere system will be at equilibrium (i.e., a stable climate/temperature) when a) and b) balance.

       d) adding CO₂ to the atmosphere makes the process in b) less efficient (IR is less easily transfered through the atmopsphere), so b) decreases and a) is now greater than b).

       e) as long as a) is greater than b), the earth-atmosphere system accumulates energy, and will heat up.

       f) as the earth-atmosphere heats up, it will lose more IR to space (step b)), because hotter objects give off more IR.

       g) the system will continue to heat up until a) and b) balance again, which will be at a warmer temperature than it was before the extra CO₂ was added.

       An analogy would be a house with a fixed heater inside, and a fixed temperature outside. The heater will warm the house until the rate of heat loss matches the output of the heater. If you add insulation to the house walls (the equivalent of adding CO₂ to the atmosphere), the heat loss will initially decrease, and the house will start to warm up. As the house warms, the increased temperature difference between the inside and outside of the house will cause the heat loss from the house to increase, until it again matches the heater output. The hosue will no longer continue to warm, but the new stable temperature inside the house will be warmer than it was before you added the extra insulation.

48640. Philippe Chantreau at 02:15 AM on 18 February 2013
       No alternative to atmospheric CO2 draw-down
       

       meb58, the basic reaction is  CH + O2 -> CO2 + H2O

       I doubt that the mass of the atmosphere can vary in any significant way. Water vapor content is a function of atmospheric temperature, any excess will precipitate as liquid or solid water.

48641. Kevin C at 01:41 AM on 18 February 2013
       16 years - Update and Frequently Asked Questions
       

       KR: That's a good rigorous statement of the situation. Also well done for avoiding the null hypothesis fallacy, an easy mistake commonly made by people on both sides of the discussion.

48642. meb58 at 01:00 AM on 18 February 2013
       No alternative to atmospheric CO2 draw-down
       

       Tom Curtis,

       I missed what I think is an important detail in your #26 reply above.  I had not realized that the H2O was a by product of the combustion process, or perhaps forgot.  If I understand this correctly then would this extra H20 affect latent heat?  I see this extra H2O as water vapor...?  ...add more heat to more water vapor and bang!

48643. meb58 at 00:32 AM on 18 February 2013
       No alternative to atmospheric CO2 draw-down
       

       Tom curtis, Jose_X,

       Thank you very much!  Your explanations are very helpful.

       ...then, the consumption of O2 occures at the point of combustion?  And forgive my own intillectual density,  even though O2 is consumed to form CO2, doesn't the mass  of the atmosphere now stay the same following the law of conservation?  I am aware that my previous question was quite the opposite...your helpful descriptions are clearing up my own mis-conceptions.

       Still, in my conception of the atmosphere, I see an atmosphere that is growing hotter.  What prevents that extra heat from escaping into space faster?  I equate my question to this example.  Let's take a one square foot cube of steel heated to 150 deg F and place it in a room set at 0 deg F.  I suspect the heat loss will follow some particular and repeatable time frame until the two reach the same temperature.  I uderstand, I think, that the heat loss may be rapid in the beginning and slow as the two begin to reach equilibrium.  However, if we now add heat doesn't the steel block lose heat faster?  ...hmmm may have just answered my own question...the source of heat we are providing is increasing over time and over-runs the ability of our atmospher to dissipate the extra heat...?

       
       Thank you...I would love to go back to school and revisit physics and chemistry.

48644. chriskoz at 23:05 PM on 17 February 2013
       2013 SkS Weekly News Roundup #7
       

       Interesting recap of the history of Most Influential Climate Science Paper which is this paper. Evidently mostly quoted paper in the history of climate science, not because it describes some break-through but because it links the climate modeling to the future of fosil fuel industry.

       The interesting piece is, that according to the article, no skeptics nor FF industry have ever denied the numbers in the paper. Instead, they've critiqued that the paper and the activists supporting it "do not understand the economic reality that FF are needed as energy source". In other words, "we are so much dependant on FF, like a drug user that is doomed & must die, such paper does not change it". I can only make one comment here: to draw such conclusion, one must be in a very sickly state of mind...

       Moderator Response: [DB] It is relatively unknown than an openly-available copy of that paywalled paper can be found here.
48645. Jose_X at 17:05 PM on 17 February 2013
       No alternative to atmospheric CO2 draw-down
       

       meb58, I should also mention that hot->cold happens "unquestionably" only in the absence of work, but adding work changes the equation. Humans are engineering chemical reactions that, along with gravity, apply work to the atmosphere as we change its composition.
       
       Sorry, I am not being more mathematically precise, but the point is that we may need to understand these contributions if we wanted to accurately verify/analyze the Second Law of Thermo.
       
       [Wikipedia: "heat always flows spontaneously from regions of higher temperature to regions of lower temperature, and never the reverse, unless external work is performed on the system."]

48646. Jose_X at 16:46 PM on 17 February 2013
       No alternative to atmospheric CO2 draw-down
       

       I think CO2 has been used (laboratory level) as a source of fuel along with sunlight in a soup of some semiconductors and various organisms. This isn't sequestration +producing energy needs in a CO2 neutral process. This is 0 sequestration + producing energy by drawing down CO2... which has the same effect.

        

48647. Jose_X at 16:40 PM on 17 February 2013
       No alternative to atmospheric CO2 draw-down
       

       meb58, a higher temperature gradient is the result of changing the material across which the gradient exists into a new material that allows a higher gradient to exist. In other words, more CO2 makes the old atmosphere into a new one that has higher insulative properties. If we replace a thin coat with a thick one, we can have a higher gradient. A paradox would exist if the material remained the same material, but changing the composition of the atmosphere is de facto creating a new intermediate material between space and the earth's surface.

48648. Tom Curtis at 12:39 PM on 17 February 2013
       No alternative to atmospheric CO2 draw-down
       

       meb58 @25, CO2 concentration has only increased 110 parts per million by volume since the pre industrial era.  Further, that increase has been accompanied by a loss of oxygen.  Not only does each molecule of CO2 formed draw one molecule of O2 from the air, but much of the CO2 comes from hydrocarbons.  That means approximately (for oil and gas) for each molecule of CO2 formed, two molecules of O2 are lost to the atmosphere, to form 1 x CO2 plus 2 x H2O.  The H2O then precipitates out of the atmosphere for a net reduction.  Further, CO2 dissolves in water more easilly than does O2, so while nearly all the O2 consumed in the reactions is lost (a small part is made up by ocean outgassing), around 50% of the CO2 formed is then dissolved in the ocean.

       The net effect, if any, will be a reduction in pressure.  However, as we are talking about changes in atmospheric composition of about 0.01%, the effect is negligible.

48649. meb58 at 12:21 PM on 17 February 2013
       No alternative to atmospheric CO2 draw-down
       

       Hello all. I am not a research scientist but I have some basic knowledge of physics and chemistry.

       
       I have a question about th greenhouse affect from a heating and cooling perspective.  I understand the a hot body will give heat off or transfer heat to a cold body if it the hot body is hot enough - entropy?   I think that I also understand the concept of partial pressure and that as a gas heats up it expands. 

       As we add more co2 to the atmosphere are we not increasing the pressure of the lower atmosphere?  If so, I would expect to see extra heat from generated from pressure as well.  In addition, since space is so cold, why does this extra heat escape faster into ooutser space due to the increased temperature gradient?   I've read that our upper atmospher is cooling and constricting.  Does this effect  help to keep the heat at lower altitudes?  Does  gravity play a role on co2 here?

       Thank you in advance.

48650. Charles08537024 at 10:48 AM on 17 February 2013
       There is no such thing as climate change denial
       

       It has been gratifying to see how many have pointed out Mr. Taylor's egregious interpretations of the Lefsrud and Meyer study, including seeing the authors of the study politely but firmly insist his interpretation was erroneous. Taylor has tried this tactic before, most recently with his "analysis" of a suvey of members of the American Meteorological Society.

       The editors of Forbes should be aware that Mr. Taylor's articles are providing rich fodder for those of us in the academy who wish to teach our students how not to interpret science.

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