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  1. 2015 SkS News Bulletin #6: Pope Francis & Climate Change

    CB Dunkerson at 22 You comment that "In short, your entire premise is built on a false assumption. Coal is no longer 'cheap energy'.

    I suggest you may have misinterpreted the tense I used.  This what I actually wrote "Cheap energy is just what the name implies. Coal has been for many years the cheapest and most abundant energy source available hence its widespread use globally".  The tense I used is the present perfect progressive tense which is frequently used to describe an event of the recent past.  That statement is perfectly correct and not at all a "false premise" as it does not indicate coal now is cheap energy.

    With regard to renewable sources of energy your assertion "As adoption of renewable energy continues to grow" is not suppofrted by the facts.  The percentage of global energy consumption supplied by renewables increased from 5.6% in 1965 to 8.9% in 2013.  Most of this increase came from hydro power. ( This does not suggest the imminent demise of fossil fuels as a source of energy.

    John Hartz  You ask me to elaborate exactly what I mean by my statement that  "Burning coal does pollute both air and water but burning coal does not preclude obtaining clean air and clean water."

    I am living in the middle of rural France a country that burns fossil fuels as an energy source.  The air where I live is "clean" so France burning coal does not preclude me enjoying clean air.  Similarly in Australia if I stay in Albany or Exmouth or Southern Cross the air is clean.  Thus despite the burning of fossil fuels in Australia does not preclude me enloying clean air.  Similarly with clean water.  Domestic water supplies in Frannce and Australia are treated, often by reverse osmosis and other processes  to meet the exacting standards for clean water laid down by health authorities.  In Perth we have also a desalination plant that produces clean water.  This production is not precluded by the burning of fossil fuels.

    I hope that is sufficient elaboration. 

    You also ask "Do you have any idea what the term, "external costs" means?"  My answer is I do. 


  2. 2015 SkS News Bulletin #6: Pope Francis & Climate Change

    @ryland #21:

    You repeatedly assert that "cheap energy" is essential to econmic growth, but your explanation of what you mean by "cheap energy" is downright shallow. Do you have any idea what the term, "external costs" means? 

  3. 2015 SkS News Bulletin #6: Pope Francis & Climate Change

    @ryland #21:

    In response to a question I had posed, you answered:

    Burning coal does pollute both air and water but burning coal does not preclude obtaining clean air and clean water.

    Please elaborate on exactly what you mean.

  4. 2015 SkS News Bulletin #6: Pope Francis & Climate Change

    Ryland, as already noted... there is no need to 'give up' cheap energy / impact standards of living to divest from fossil fuels. Even without considering the huge environmental and health costs of fossil fuels, renewable power is now drawing even with the cost of fossil fuel power world-wide. As adoption of renewable energy continues to grow it will quickly become significantly less expensive than fossil fuels.

    Indeed, your claim that the "developing world" needs 'cheap' fossil fuel power is belied by the fact that many countries which previously had very little electrical power are now developing wind and solar power... because they cost less. In short, your entire premise is built on a false assumption. Coal is no longer 'cheap energy'.

  5. 2015 SkS News Bulletin #6: Pope Francis & Climate Change

    John Hartz

    I also applied clean to water but not to any of the other entities.  I applied clean to water because it has been an essential prerequisite of human society for millenia.  Similarly cheap energy has been a major contributor to the rise of Western society.  Cheap energy is just what the name implies.  Coal has been for many years the  cheapest and most abundant energy source available hence its widespread use globally.  

    You ask if I think burning coal is not compatible with clean air and water. Burning coal does pollute both air and water but burning coal does not preclude obtaining clean air and clean water.   

  6. 2015 SkS Weekly News Roundup #27B

    That first-linked article, "Hard Deadline," is quite a doozy.

    It just seems like almost everyone is living in some deluded fantasy.

    Any ideas on how to bring production of all fossil-death-fuel machines and plants to a halt by 2018?

  7. 2015 SkS News Bulletin #6: Pope Francis & Climate Change

    @ryland #18:

    Do you acknowlege that the burning of fossil fuels is not compatible with clean air and clean water?

  8. 2015 SkS News Bulletin #6: Pope Francis & Climate Change

    @ryland #18:

    You state: 

    Other luxuries are clean water, food, housing sanitation, medicines and cheap energy.

    Why do you apply the adjective "cheap" to only energy?

    What is your working definition of "cheap energy"?

  9. 2015 SkS News Bulletin #6: Pope Francis & Climate Change

    CB Dunkerson a couple of points.  Even though naturl gas produces less CO2 than coal per it is a fossil fuel so its use is still adding to CO2.

    You mention the advantages you say scaddenp has it exactly backwards but your comments too indicate a lack of understanding of the situation.  Greeks didn't like the way the austerity program impacted on their wages and pensions and employment and  liivng standards so voted against that program continuing.  Similarly those in the developing world will not accept they should be denied their use of fossll  fuels to generate cheap energy because it will impact on their standard of living.  No difference from the attitude of the Greeks to the austerity program.  

    PhilippeChantreau  In today's world luxury for many is remaining alive and/or escaping from terroism.  Other luxuries are clean water, food, housing sanitation, medicines and cheap energy

  10. 2015 SkS News Bulletin #6: Pope Francis & Climate Change

    Scaddenp, to my way of thinking you've got your analogy exactly backwards. Greece did vote for reform... rejecting the 'status quo' austerity policies which have been crippling their economy the past several years just as we should reject continued unhealthy reliance on fossil fuels. Likewise, nature has already proven far more flexible than 'euro bankers'. Greece needs to invest in growth that benefits everyone rather than clinging to a failed system that benefits only a few wealthy interests... ditto the world at large in regards to fossil fuels.

  11. 2015 SkS News Bulletin #6: Pope Francis & Climate Change

    Ryland, if we wanted to help the coal miners (in Kentucky/the US) we should have started ~60 years ago. Since then the number of coal miners in the US declined by about 90%... before natural gas, wind, and solar started to take off. There are now fewer coal miners than there are wind and solar power installers.

    As to your view that coal miners subscribe to the belief that we should embrace cheap energy... not if they want to remain coal miners. Natural gas is cheaper than coal everywhere in the US, and wind and solar are now cheaper in many parts of the country (and will be so nearly everywhere in just a few years)... even without taking the health and environmental costs of coal into account. That's why there has been almost no new coal power deployment in the US since 2008. US coal consumption is now near 1970s levels.

    In other parts of the world coal is still 'cheap' if the health and environmental costs are ignored, but even that won't be true for much longer. At this point, one of the best ways to help coal miners would be to train them on wind and solar power... so they will have jobs when coal becomes globally obsolete over the course of the next couple of decades.

  12. In charts: how a revenue neutral carbon tax cuts emissions, creates jobs, grows the economy

    davytw @34, your first reference seems to be employing that famous fallacy of argument, "post hoc, ergo propter something else intirely".  Specifically, looking at the chart they produce as evidence, the largest perturbation of the BC economy in 2008 was the global financial crisis.  To totally ignore that as a potentially relevant factor shows that it is indeed an article for The American [non]Thinker.

    More troubling is the way the American [non]Thinker ignore the pattern clear in the first graph, of a rise from near Canadian average growth in 2003 and prior, to a peak in 2005 with a clear decline thereafter.  That is, they ignore the evidence that the decline back to the Canadian average growth preceded the introduction of the carbon tax, and indeed was the consequence of a brief spurt in growth followed by a return to Canadian average growth.  It would be interesting to know what happened in 2003 to cause that spurt in growth.  It would also be interesting to know Canadian and BC population growth statistics where so different in the five years prior to 2008 (as evidenced by the different pattern in real GDP growth (first graph) and real per capita GDP growth (second graph), but clearly neither pattern is related to the carbon tax (unless the American [non]Thinker also claims to have discovered backward causation in time).


  13. In charts: how a revenue neutral carbon tax cuts emissions, creates jobs, grows the economy

    PS - when I say "the success or lack thereof" in the previous post, I mean, of BC's carbon tax.  

  14. In charts: how a revenue neutral carbon tax cuts emissions, creates jobs, grows the economy

    I posted this in a different thread, but haven't gotten a response, so thought I'd try here (and if I may add, I still think email notifications of thread activity are the way to go in keeping threads alive!):

    I've been arguing about the success or lack thereof in another forum:

    Climate Change - Impacts Part 2

    The opposing argument against the info I posted from SkS are as follows:

    1) while BC is keeping pace with the rest of Canada, it was doing better before 2008:

    BC Carbon Tax Damage

    2) it's unlikely that a few cents' tax had such a dramatic effect on consumption:

    BC's carbon tax has had little effect on fuel consumption

    3) in 2014, gas consumption in BC is back up to where it was in 2008:
    No B.C. carbon tax miracle on 120th St.

    I'm not posting any of this because I oppose carbon pricing; I definitely favor it.  But I do like to be honest about what the evidence is and what inferences can be made.  Can anyone help me defend the BC tax against these critiques?

  15. PhilippeChantreau at 16:58 PM on 6 July 2015
    2015 SkS News Bulletin #6: Pope Francis & Climate Change

    Ryland cites an ideology ladden article above with this: "Real concern for the poor would result in an embrace of cheap energy, including fossil fuels, which, along with market capitalism and the rule of law, has been responsible for dragging more people out of the poverty and democratising luxury than any number of sympathic prayers."

    What's really cheap in this article is the rethoric. The real cost of the so-called cheap energies has been stored away or externalized and is piling up to make a for an enormous bill that will be beyond the means of all mankind put together. Even the Wall Street clowns won't have funny maths to get out of that one, especially in light of their math performance that culminated in 2008. Frankly, it seems that the clergy knows every bit as much about economics than these bufoons did. At least, their prayers didn't cost trillions to the World economy.

    As for how much concern for the poor happens in the free market fanatic circles, well, do we really have to stoop that low? Back in the days, free market was of course responsible for dragging out of poverty the 7 years old children working in textile mills 12 hours a day, as we all know.

    "Democratize luxury." My favorite. What a load of dung. Luxury would then consist of having light, running water and heat in the winter. By 14th century standards, that's definitely luxury. Unlike, say, having your kids go to a $50k/year preschool, or debating whether or not to run your yacht as a commercial charter operation in the Caribean during these long months when you can't use it because you're too busy with that pesky thing called work and you're stuck with private jets for transportation. Luxury is such a relative notion. For some, it's a high probability of having meals lined up next week. Perhaps we'll all get back to that point one day. The way things are going now, it certainly seems we're trying. A great equalizing of sorts...

  16. 2015 SkS News Bulletin #6: Pope Francis & Climate Change

    In the context of overcoming human inertia re the mitigation of manmade climate change, the following caught my eye...

    People are more likely to respond to the issue of climate change if they can see it with their own eyes, research on thermal imaging has found.

    Sabine Pahl and colleagues investigated ways to motivate people to improve the energy efficiency of their homes. They tried three strategies, including a home energy audit, a text report about energy efficiency and taking photos with a thermal imaging camera.

    “We found across several studies that thermal images of their own homes are really engaging to householders,” says Dr Pahl, Associate Professor in Psychology at the University of Plymouth who will be presenting at the Our Common Future Under Climate Change conference in Paris from 7-10 July.

    Making heat visible: Thermal images motivate household energy efficiency, Our Common Future, June 30, 2015

  17. 2015 SkS News Bulletin #6: Pope Francis & Climate Change

    To me, voting against a carbon tax feels very like the Greek vote against reform. Okay, that is simplistic, but Greece cannot continue the way is has in the past anymore than we can continue with FF as we have. I think nature is rather more uncompromising than euro bankers.

  18. 2015 SkS News Bulletin #6: Pope Francis & Climate Change

    ryland @9, it is quite obvious that if it is acceptable, in 2018, to replace existing houses or to build carbon neutral houses, then it is also acceptable to replace an existing house with two 50% carbon neutral houses; or to modify an existing house to halve its carbon emissions, and build a new house with just 50% of current emissions per house, and so on.  In particular, each 1% reduction in emissions from national electricity generation makes room for further economic growth.

    Ergo, Stephen Leahy's formula sounds dramatic, it really represents only a formula for no more emissions growth from 2018.  Rather than a cessation of emissions growth (and hence ongoing growth in CO2 concentration), what the world needs is the almost complete elimination of net anthropogenic emissions by 2050, and hence on the order of a 3% reduction in global emissions per annum.  That is a doable target.  Even with slow initial progression, a genuine attempt to move in that direction will allow very rapid strides in the near future.  It is not, however, something on which we can delay - and each year that we delay - each year you win your struggle for inaction makes the cost of transition higher (because it must be more rapid), and the end benefit lower (because of increased global warming durring the delay).

  19. 2015 SkS News Bulletin #6: Pope Francis & Climate Change

    Ryland, I am quite sure that if the world doesnt divest of FF, then the people who will pay with be largely the poor, and largely those who not contributed to global warming nor benefited from FF. Getting off FF will very likely (without some new tech) mean paying for energy but I find the idea the the West shouldnt do so because of "damage to the economy" as immoral and repulse. Is it realistic? I dont know. How many people out there feel like you apparently do? I am heartened when talking to the younger generation who seem much more prepared to seek justice. Would they vote for a carbon tax? yes, I think they would.

  20. 2015 SkS News Bulletin #6: Pope Francis & Climate Change

    @ryland #9:

    It is extremely hard for any indidvidual to get their head around the enormity of what we are doing to the climate system of our only home planet. We have stark choices to make if we are to avoid self-extinction. Time is not on our side.

  21. 2015 SkS News Bulletin #6: Pope Francis & Climate Change

    John Hartz @7.  Do you really believe that the world will act as suggested in the article to which you refer?  This statement, see below shows a staggering degree of naivety

    “By 2018, no new cars, homes, schools, factories, or electrical power plants should be built anywhere in the world, ever again unless they’re either replacements for old ones or are carbon neutral? Are you sure I worked that out right?” I asked Steve Davis of the University of California, co-author of a new climate study'.

    If this is what must occur then the world is doomed because it is a totally unrealistic proposition as time will certainly tell.  Is the building of the houses required for the ever expanding human population going to be halted?  What will be the cost of making all new homes carbon neutral? Who will bear the costs of, for example, insulation?  Will these strictures apply globally?  

    The mind boggles.

  22. 2015 SkS News Bulletin #6: Pope Francis & Climate Change

    Divestment begets Investment: mixed market economies mean a winner is always picked and if the natural oligopoly is leaning away from fossil fuels then a carbon fee it will be!

    Governments simply provide and if fossil fuels aren't producing the comparative goods anymore then say hello to a new world.

    (Maybe we will mine moonrock for nuclear fusion fuel afterall...)

  23. 2015 SkS News Bulletin #6: Pope Francis & Climate Change

    @ ryland #6:

    What will happen if the human race cannot get its act together within three years is starkly set forth in:

    A hard deadline: We must stop building new carbon infrastructure by 2018 by Stephen Leahy, The Leap, July 2, 2015

  24. 2015 SkS News Bulletin #6: Pope Francis & Climate Change

    I think you're right about the carbon tax Tom Curtis but will it happen?  And if not, then what?

  25. 2015 SkS News Bulletin #6: Pope Francis & Climate Change

    Ryland, the tobacco industry proves very effectively just how well "free market economics" serves the poor.  Likewise Nestle's promotion of baby formulas in the third world.  Any presumption that "free markets", by which is meant unrestrained corporate search for profits, will automatically help the poor represents simply ideology in action.

    In the particular case of fossil fuels, a universal carbon tax in western nations would reduce demand for fossil fuels in those nations, thereby reducing the price of fossil fuels to poor nations.  At the same time it would increase research into making alternative energy sources cheaper, thereby bringing alternative energy into the price range of the poor.  Likewise, divestment in fossil fuel portfolios can be coupled with investment in renewable energy with the effect of making renewable energy cheaper.

  26. 2015 SkS News Bulletin #6: Pope Francis & Climate Change

    Hi Ryland

    For a large fraction of the world's 'poor', they aren't on a functioning grid anyway, so coal won't help them much. localised generation like solar and wind is much easier to deploy.

    It's also not an either/or scenario for the working poor in affluent nations. For instance, the carbon tax in Australia came with an energy rebate, thus avoiding the 'little old ladies dying from cold because they refuse to turn on their expensive heating" meme. There's no reason why we can't help the needy and ensure the long-term prospects of our environment.

    Most of the people who tell us how we should help the poor by doing some other alternative (Lomborg etc) have no actual interest in helping the poor. It's a smokescreen.

  27. 2015 SkS News Bulletin #6: Pope Francis & Climate Change

    An editorial in this weekend's  Australian Financial Review (a Fairfax paper) asks this question "Should churches be saving souls or saving the planet?

    The editorial then goes on to address this question as follows:

    "Perhaps Australia's churches would argue they're doing both. Unfortunately, those pushing fossil fuel divestment campaigns are doing neither."

    It then goes on 

    "At the root of the problem is a fundamental ignorance of economics among much of the clergy. Many bishops and church leaders are all too ready to engage in "lapel-pin political slogans", crying "neo-liberalism", or "fossil fuels", but without considering that without them all people, particularly the poor and downtrodden for whom the church claims particular concern, would be worse off."

    and concludes:

    "Real concern for the poor would result in an embrace of cheap energy, including fossil fuels, which, along with market capitalism and the rule of law, has been responsible for dragging more people out of the poverty and democratising luxury than any number of sympathic prayers."

    I suspect the coal miners of Kentucky and indeed elsewhere would subscribe to this view.  I certainly do but i suspect that my truthful comment might be self defeating

  28. More evidence that global warming is intensifying extreme weather

    I suspect effects related to rate of change, in addition to effects related to change. The only basis for this is that I have noticed peculiarities during change from one quasi-stable state thru a threshold of instability to a different quasi-stable state. Water coming to a boil in a pot on the stove. Fall and Spring, between Winter and Summer. These transitions are not merely a mix of the "From" and "To" quasi-stable states. (From laminar flow to turbulent flow is not an example.)

  29. IPCC overestimate temperature rise

    Tom Curtis @62

    Thanks Tom, that's very clear.

  30. IPCC overestimate temperature rise

    APT @61:

    1)  The primary reason for the larger uncertainty for the shorter time period is that there are 43.5% fewer data points.

    2) Using the Berkeley Earth global dataset, the trend from 1990 to current is 0.164 +/- 0.066 C per decade.  From 2000 to current it is 0.095 +/- 0.129 C per decade.  Both are "statistically indistinguishable" from the model projected 0.2 C per decade.  Further, the only of the two trends long enough to be significant has a median value at 82% of the model projected trends, showing that at worst the models only mildly overestimate current temperature trends.

    3)  UAH v6 is very similar to RSS in its values.  Using the SkS trend calculator we see that the RSS trend over the period 1979-current is 0.121 +/- 0.064 C per decade.  UAH v6 is likely to have a similar error margin.  The primary reasons RSS trends are lower than surface trends are, first, a greater reponsiveness to ENSO fluctuations resulting in a greater reduction in the post 1998 trend from the rapid rise in SOI values (ie trend towards more and stronger La Nina events), and second, limited reporting of Arctic values with their very high temperature trends.  As to whether the UAH result is accurate, v6 has not yet been reported in peer reviewed literature so that it is not yet possible to determine if the reported values correctly report the values determined by the (as yet not formally described) v6 method.  More generally, there is a significant scientific debate as to whether satellite values are more or less accurate than surface values, and as to how exactly they should be related in that they do not strictly report the same thing.  For my money, I no with a fairly high degree of confidence that surface values (particularly BEST and GISS) are accurate; but think there is good reason to doubt the accuracy of the satellite values, even for the Lower Troposphere, let alone for the actual surface.

  31. CO2 measurements are suspect

    Tom Curtis @79
    Thanks for the reference and explanation. Interesting and useful.

  32. Cracking the mystery of the corrosive ocean

    @17, possibly worth knowing en masse to prevent the resource bottlenecks of panic that are predicted!

  33. IPCC overestimate temperature rise

    Hi everyone,

    I have some questions:
    In the intermediate version, observed data is given as 0.15 ± 0.08°C per decade from 1990 to 2012, and 0.06 ± 0.16ºC from 2000 to 2012. Why is the uncertainty so much greater for the 2000 to 2012 observed data?

    The data here only goes to 2012. How do the projections compare with data up to 2015?
    Looking for more up-to-date information, I found a piece on UAH 6.0 to 2015 on Dr. Roy Spencer's website:
    Is his figure of 0.114ºC per decade from 1979 to 2015 accurate? It's certainly precise, why no error margin?

    In anticipation of the kind of responses I got last time I asked questions on this website, let me be clear that this is a genuine request for information, not an argument.

  34. Cracking the mystery of the corrosive ocean


     Colourful Language is what haunts this 24-7 Hollywood-inspired world of buy-buy-buy-NOW!!

  35. Cracking the mystery of the corrosive ocean


      I -for one- appreciate this insight into the phenomenon!

  36. Cracking the mystery of the corrosive ocean

    I do wonder if a quick lesson in what pH actually measures would be worthwhile. There is no "neutral" pH as such. Water is famously H2O. However, the hydrogen in H2O isn't as sticky as it could be so pure water also contains H1O and H3O. pH is actually a measure of the stickiness of hydrogen within a solution. (It's actually hydrogen ions. There's an electrical charge involved +H.) In pure water one-in-10million mollecules are H30, a ratio which can also be expressed as 1:107. This 7 is the measure of pH, the equilibrium stickiness of hydrogen in pure water. Change the solution by adding stuff with different stickiness and the stickiness will obviously change.

    So something with a low pH has more +H flying about which makes it more acidic than something with a high pH where the hydrogen is stickier so doesn't fly about so much. But with high pH there is still some unstuck +H. Thus there is no "neutral" as such. The popular idea that alkali is the opposite of acid is a bit of a nonsense. But explaining that is a whole lot more complicated. 

  37. Cracking the mystery of the corrosive ocean

    Sinbod @15:

    "Is it fair to say that anything outside the prefered Ph level is "corrosive"?"

    Probably not.  Low pH (or insufficient aragonite) will result in more difficulty building and maintaining shells.  High pH will probably result in either wasted metabolic energy (ie, the shell building process is not as efficient as it could be in the conditions), and/or excess calcium deposition.  The later may deform shells or result in depositions in otherwise harmfull locations (ie, the mollusc equivalent of gout or kidney stones).  Both the metabolic inefficiency and excess deposition may make species vulnerable to displacement by invasive species better adapted to the new conditions.  Other than that, however, neither will cause short term problems SFAIK.

  38. michael sweet at 11:37 AM on 4 July 2015
    Cracking the mystery of the corrosive ocean


    The issue here is calcium carbonate dissolving due to lower pH.  An increase in pH, while it would be harmful to animals, would not dissolve the shells of shellfish and corals.  Therefor an increase in pH would not be corrosive in the way acidic water is.  I think corrosive is being used because it is a description of the action of the acidic water.

  39. Cracking the mystery of the corrosive ocean

    Excellent explanation. Various species of organisms have there own sweet spot and anything outside that range is potentially quite harmful to development. In theory stomach bacteria would find a neutral Ph environment quite distasteful. Is it fair to say that anything outside the prefered Ph level is "corrosive"?

    Moderator Response:

    [Rob P] - No. See my previous comment. Whether or not seawater is corrosive to calcium carbonate shells and skeletons depends on the calcium carbonate saturation state which decreases with geologically-rapid injections of carbon dioxide into the atmosphere.

    On the left-hand column of the page is a series called OA not OK. It was written by experts in this field and goes into quite some detail. The answer to many common myths about ocean acidification can be found there.   

  40. michael sweet at 11:20 AM on 4 July 2015
    Cracking the mystery of the corrosive ocean


    Googling "Washington oysters pH" gives many hits on problems with pH in the Washington oyster aquaculture program.  Most are newspapers but this one is from NOAA.  When I Googled "Washington Oysters parasite" I got no hits.  Can you cite a reference for your claim that the problem was parasites?

    There are several articles that detail acidic water killing the oyster spat.  They monitor the pH of the incoming water at the hatcheries and have resolved the issue for the present.  Washington is first affected because upwelling water there is from further north and is not very old.  Others will be affected as the acidic water moves south on currents.  As CO2 concentrations in the air increase, pH will decrease more and more.

    As Tom said, some species will be affected earlier than others.  These oysters are vulerable when they are very small.  Other species will be affected differently (although young animals are often less resilient than older animals).

    Freah water species have evolved to survive in lower pH.  The biggest problem is not the absolute pH but the change from what the animals are adapted to.  It is very damaging for most animals to have change from optimal conditions.  

  41. Cracking the mystery of the corrosive ocean

    Sinbod @12, generating shells requires energy.  How much energy will depend on the availability of the base materials in the environment, and the corrosivity of the environment to the shell.  Because in most circumstances these will be fairly stable features, animals with shells will evolve specific mechanisms to generate shells in their particular environments, tending towards the least metabolic cost pathway available.  As a result, we would not expect corrosivity to be an equal factor across species regardless of the background pH in their normal environment.  Further, some species may be robust to change in pH within a range because that range of pH is the normal in their environment.  Further, some species to be more robust to change in pH outside the normal range in their environment, not due to evolved capability but just by chance, depending on the specific mechanism of shell generation they use.

    The issue, therefore, is not whether there is some magic number which is corrosive for shell fish.  Rather, for all shell fish there will be a pH range (different for different species) which represents the mean and deviation normally experienced in their environment, and pushing the pH range below the range of variability will be deleterious to the species.  At a minimum level it will be harmful by either/or increasing the metabolic cost of maintaining the shell or thining the shell resulting in it being less protection against predators.  At the high end, the species will be unable to grow shells at all.  The greater the decrease in pH the greater the risk of a high end response.  Further, the more rapid the change in pH (and hence the less time for an evolved response), the greater the risk of a high end response.

    Finally, as I understand it, the real issue is aroganite saturation, rather than the pH itself, with pH being a good proxy for aragonite saturation (but chemistry is not my strong suite so don't quote me on that).

  42. Cracking the mystery of the corrosive ocean

    Thanks, the relativity of the material, understood.

    Note, I live in the northwest. I was concerned about the shell fish issue however when I read the acidification paper in detail it was clear that the results were ambiguous with some species unchanged, some worse and some better off. I also reviewed the oyster issue which was a problem with parasites... Have you read the details?

    Since there are fresh water shellfish, is 8 some kind magic Ph bad spot for a specific type of shellfish?

    Note, not denying anything - just like to understand what on the surface seems contradictory.

    Moderator Response:

    [Rob P] - The die-off of larval oysters in the hatcheries was due to the intake of corrosive (carbonate undersaturated) sea water. See my SkS post: Corrosive Seawater, Not Low pH, Implicated As Cause of Oyster Deaths.

    It's not pH per se that is the issue, as the oceans will remain alkaline, but rather the decline in carbonate ion abundance that results when more carbon dioxide is dissolved into the oceans. As carbonate ion abundance decreases so does the carbonate saturation state. When undersaturation is reached seawater becomes physically corrosive to calcium carbonate forms.    

  43. michael sweet at 09:49 AM on 4 July 2015
    Cracking the mystery of the corrosive ocean


    The pH at which water is corrosive depends on the reactivity of the material.  For sodium, pH 14 water is severely corrosive.  

    For this discussion the question is at what pH is sea water corrosive to calcium carbonate.  It turns out that pH is about pH 8.0.  Since the current average pH of the ocean is only slightly above that, it only requires a small amount of acidification to affect shell forming animals.  

    In high latitudes, carbon dioxide is more soluble in the ocean becasue the temperature of the water is lower.  In some of these locations the ocean is already becoming corrosive to shell forming animals.  Oregon and Washington have observed die offs of oyster larve from acidified sea water.

  44. Cracking the mystery of the corrosive ocean

    My point isn't about the term acidification, it's about claiming that a slightly less alkaline ocean is somehow going to be more corrosive. If PH is heading towards neutral that doesnt make sense. In order for the oceans to become more corrosive, the PH level would have to go either somewhat higher a lot lower (at least below 7) - in 300 million years the oceans have been alkaline. So what gives with the corrosive statement.

    Moderator Response:

    [JH] Pease read the intermediate version of the SkS rebuttal article, Ocean acidification: global warming's evil twin.

  45. Cracking the mystery of the corrosive ocean


    To follow up on Rob Honeycutt's comment, you are still allowed to say "I'm going south for a holiday this winter", even if you are only going from New York to Miami. You don't have to pass into the southern hemisphere before you are "going south".

  46. Rob Honeycutt at 09:25 AM on 4 July 2015
    Cracking the mystery of the corrosive ocean

    Sinbod...  No, "acidification" does not require that you be on the acid side of the scale. It merely requires that you're moving the pH in that direction.

  47. Cracking the mystery of the corrosive ocean

    "But our findings suggest other factors made the Atlantic far more corrosive than the rest of the world’s oceans. This means that sediments in the Atlantic Ocean are not representative of worldwide CO2 concentrations during the PETM."

    "Corrosive" - I don't understand, the oceans are alkaline, if they are moving towards the acid side of the PH scale, wouldn't they first have to become more neutral to get there? Aqueous solutions are corrosive at either end of the PH scale but the middle of the scale is the least corrosive. Are you claiming that the oceans actually crossed into being on the acid side of the PH scale like fresh water?

  48. Watts' New Paper - Analysis and Critique

    [PS] Hypothesizing about an unseen future paper is fruitless and frankly offtopic. I would strongly suggest that no further discussion happen on this subject until there is an actual paper to discuss.

    I don't see why. But as you wish.

    Moderator Response:

    [RH] ***Note to all.*** This conversation has to stop until an actual paper is provided. All follow up comments will be deleted until such time Evan produces a paper for us to read.

  49. Watts' New Paper - Analysis and Critique

    Tamino and Ramsdorf have both put out blogs that show there are no cooling (or flat) periods in the global record for the past 50 years.

    There is perceptible Tmean cooling in the US from 1999-2008.

    Class 1\2 (Raw+MMTS adjustment): -0.135C/decade

    Class 3\4\5 (Raw + MMTS adjustment): -0.309C/decade

    Class 1\2 (NOAA-adjusted): -0.232C/decade

    Class 3\4\5 (NOAA-adjusted): -0.398C/decade

    As you can see, the cooling is exaggerated by poor microsite and made worse by adjustment. Same happens the other way around, which is most of the time.

  50. Watts' New Paper - Analysis and Critique

    If you draw a trend from 1998-2008 the 'heat sinks' react one way, but if you draw the trend from 1998-2015 they react differently?

    The trend from ~2001 to 2015 is flat. Therefore, there will be no divergence over time for that period. What we want to examine is if there is a divergence during a strong cooling period and if so, how much that divergence is. Including a long string of flat data on the end muddies the signal and places 2008 near the middle, which washes out the slope.

    For that reason, we also supply 1979-2008 data in order to show a warming-only period.

    I repeat, we are not trying to say that our 1999-2008 series is representative of the US or global longterm trend. We are only using it to demonstrate the effect of heat sink during a period of significant cooling.

    How can a heat sink react to a trend line? A trend line isn't a physical thing. It's an exploratory tool. There is no way a heat sink can be reacting to temps a decade ago.

    A heat sink's effect on any datapoint is relevant in relation to its given place in a given series. Start point, end pont, trend. If a relatively cooling period occurs near the start of the time series, the trendline is increased. If it occurs duing the end of the time series, it decreases the trendline.

    If a blip occurs smack in the middle of a time series, it doesn't affect the trend a hoot in hell no matter how high or how low it is. But a step change has the greatest effect in the middle of a time series and the smallest at either end.

    It's not about a sensor, or even a datapoint. It's about what point the datapoint occurs in the series, be it running warm or cool.

    During a warming phase, the heat sink's temperature rises dispropotionately. It is a function of that difference over time that is the spurious amount added to the sensor reading from the start to end point. If it is a cooling trend, the effect works in reverse.

    Moderator Response:

    [PS] Hypothesizing about an unseen future paper is fruitless and frankly offtopic. I would strongly suggest that no further discussion happen on this subject until there is an actual paper to discuss.

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