Climate Science Glossary

Term Lookup

Enter a term in the search box to find its definition.

Settings

Use the controls in the far right panel to increase or decrease the number of terms automatically displayed (or to completely turn that feature off).

Term Lookup

Settings


All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

Home Arguments Software Resources Comments The Consensus Project Translations About Support

Bluesky Facebook LinkedIn Mastodon MeWe

Twitter YouTube RSS Posts RSS Comments Email Subscribe


Climate's changed before
It's the sun
It's not bad
There is no consensus
It's cooling
Models are unreliable
Temp record is unreliable
Animals and plants can adapt
It hasn't warmed since 1998
Antarctica is gaining ice
View All Arguments...



Username
Password
New? Register here
Forgot your password?

Latest Posts

Archives

Recent Comments

Prev  912  913  914  915  916  917  918  919  920  921  922  923  924  925  926  927  Next

Comments 45951 to 46000:

  1. Nils-Axel Mörner is Wrong About Sea Level Rise

    In a prior post, I reffered to a photoshopped picture used by Morner as "evidence" of the lack of sea level rise in the Maldives.  I have been unable to find the scientific paper  in which it was located, and so must withdraw the claim that it appeared in such.  Never-the-less, Morner has frequently used this tree in his presentations about sea level rise, including at WUWT and in an interview for 21st Century Science and Technology (PDF).  

    The story Morner gives is that he knew of the tree from visits to the Maldives in the 50s, and that its continued survival in the tide zone is evidence that sea levels have not risen.  That basic story has some embellishments I will discuss below.  Two accompany the story, four different pictures (plus B&W variants) of Morner's Tree are used.  There are two grainy "before pictures".  One of those has a mark identifying it as a propriety photograh in the lower right corner, strongly suggesting it is a stock photo and has no relationship to Morner's tree (other than species and isolated location).  There are also to "after photos", of which one, due to the distinct slope of the intertidal zone where it is located, is also obviously not the same tree as the other.  It is not at all clear that either of these dubious photos was actually provided by Morner, although both have circulated among climate "skeptics" as illustrating Morner's tree.

    The two "genuine" photos are produced below from WUWT.  The "before" tree is in the lower left corner, the "after tree" in the upper right corner.

    The first thing to notice is that they are not identifiable as the same tree.  Indeed, if the large oval stone in the left foreground of the upper picture is the same stone as that in the right midground of the lower picture, they are not the same tree.  The upper right tree is far closer to the stone than is the one in the lower right.  Probably the stones are merely similar, rather than the same, in which case the pictures are still not of the same tree.

    That, however, is a minor point.

    Far more significant is the photoshopping of the upper right picture.  This is far clearer in the version of the picture from the 21st Century Science and Technology interview, used as the basis of the picture below.

    If you look closely at the picture you can see two edit lines where two pictures have been grafted together.  The first in order of editing (marked by the orange arrow) is shown by the sharp cut off of the tree's shadow along with a subtle change of colouration in the stones.  I am not expert on imaging fraud, so it is possible that I am wrong about that one, although I doubt it. 

    The second edit line is definite.  Not only are the rock colours on either side of the line clearly distinct, but there is a clear discontinuity between the roots and lower branches of the tree and the leaves and upper branches.  The discontinuity even orphans a sawn of branch on the left side of the tree, leaving it apparently floating in mid air.

    Not only is the photo fishy, so is the attached story.  The tale that the island on which the tree is located, Viligilli (or Villingili) is a prison island falls on the simple fact that no prison is located on the island (see also google map).  The notion that the tree was uprooted and then replanted fails on the fact that the roots shown are solidly attached to the earth below, with no disturbance of that Earth.  And with that part of the tale, so also goes the theory that Australian science students are both vandalous and fraudulent.

    DJ at WUWT quotes a discussion of the story by a purported Maldivian.  That anonymous source claims Viligilli was a prison island until 1973, which rescues part of Morner's story.  They also go on to say, however:

    "The tree is called ironwood (Pemphis acidula). It’s known for its resilience against salt and is usually the dominant species in very high wave energy and salt spray zones. Having traveled to over 600 islands in Maldives I have witnessed a number of such one ‘tree’s’. The tree in question simply has withstood erosion in the last 10 or so years while weaker trees around it fell. Aerial photographs of 1968/1969, 1998 and 2004 shows that the area is relatively stable with occasional erosion. There have been a number of trees in this specific area of the island like the one in question which have remain separated from the island. It is part of the erosion process. The tree most likely was there 50 years ago but it certainly was not alone as it is now. It is these kinds of adhoc observation based conclusions rather than rigorous assessments which make me question the findings of Morner."

    (My emphasis)

    If we accept the authenticity of this Maldivian (and hence the partial corroboration of Morner's account) then we must also accept their expertise on such isolated trees.

    Indeed, on first principles we can see that account to be correct.  If sea level is falling, the intertidal zone will be in the process of being colonized by a species (Pemphis acidula) that can grow in that region.  We would consequently expect to see few mature trees, but a significant number of immature trees colonizing the zone.   A stable sea level would be evidenced by a number of mature trees in thickets, as is common for the species.  Only with rising sea levels would sole mature survivors of former thickets remain.  So, in as much as Morner's photoshopped picture is evidence of anything, it is evidence of rising sea levels.  But it takes the sort of "skepticism" that can't even notice such blatant photoshopping to not notice that.

  2. Mond from Oz at 10:09 AM on 2 May 2013
    Forks in the Road: Last Exit to Two Degrees

    We need to look very carefully at the contribution of the other GGs, and in this connection I note that T.J.Blasing ( CDIAC, Recent Greenhouse Gas Concentrations, updated Feb 2013) calculates a combined 1.04 Watts per square meter of increased radiative forcing from CH4, N2O and O3, plus a small 0.34 from the others. That totals to 1.384 W/m, surely not an insignificant addition to the increased radiative forcing of 1.85W/m from CO2 alone. Butler (the NOAA Annual Greenhouse Gas Index 2012) calculates a CO2 equivalent of 473 ppmv for 2011. And that, with all the uncertainties, says to me that we have already, very probably, jumped the 2 degree barrier.

  3. Global Warming: Not Reversible, But Stoppable

    Andy Skuce: "if we lived in a world where the economy doubled in size every few days?"

    That depends on exactly how you propose to measure the size of the economy. If you want to use GDP without accounting for inflation, then we have historical events that tell us how things will go. It's called hyperinflation, and it's not a pretty sight.

  4. Roy Spencer's Catholic Online Climate Myths

    Alexandre @8 - we do have the contradictions database, but it just lists generic arguments, not attributed to specific individuals.

  5. Roy Spencer's Catholic Online Climate Myths

    Contrarians often contradict one another (well, they often contradict themselves...) For example, Spencer says it's some random cloud feedback that drives climate, whereas Willie Soon says it's the sun.

    Would it be possible to assemble an "alternative theory" database to compare just how heterogeneous the small "skeptic" lot is? Is there already such a thing somewhere?

    The Climate Misinformer database here at SkS is great, but each misinformer page looks more like a Gish Gallop (understandably) then the alternative theory the guy in question defends.

     

    Just for the record, I have never seen a climate skeptic say publicly that some fellow skeptic was wrong - even though each of them proposes very different things.

  6. Global Warming: Not Reversible, But Stoppable

    Completely off topic, but to cool not to mention:  Hanson 94 at least got one prediction right:

    "The future is hard to predict. We may feel confident that eventually space will be colonized, or that eventually we'll make stuff by putting each atom just where we want it. But so many other changes may happen before and during those changes that it is hard to say with much confidence how space travel or nanotechnology may affect the ordinary person. Our vision seems to fade into a fog of possibilities."

    (My emphasis)

    Lo!  The world's smallest movie!

    Of course, this merely reminds me of what they say about stopped clocks, or, perhaps more aptly in Hanson's case, a clock I once saw whose hour and minute hands tracked the second hand, and hence was also right twice a day (and accurate never). 

  7. funglestrumpet at 06:30 AM on 2 May 2013
    Leave It in the Ground, Climate Activists Demand

    @ClimateChangeExtremist

    Make the thorium fuelled reactors the liquid flouride type. and also make them both small and modular so that they can be manufactured on a production line in each country with the modules able to be shipped by road on the final leg of the journey to their designated location for assembly on arrival and you get my full support.

    While they will not replace the liquid energy that oil currently provides, they would certainly motivate the development of techniques to electrify the transport system, especially as oil climbs relentlessly higher in price.

    I suppose what we really need is a Manhattan type project to resolve the final design issues and, seeing as they are so safe, a relaxation of any planning permissions that could hold up their progress. As for NIMBYs, well ...

  8. william5331 at 06:30 AM on 2 May 2013
    Forks in the Road: Last Exit to Two Degrees

    The only way I can see that the necessary measures will be taken is if America adopts representative government such as we have in New Zealand.  Since this would shaft most of the congress and senate, there is zero chance that it will happen.  Right from it's inception, the government of the USA has been corrupt, looking after vested interests instead of the good of it's citizens and warring on other countries to steal their resources and nothing has changed.  Our only hope is that so many states, cities, businesses and private people in the states are doing what is necessary.  The American people are great, their government, not.  Remember Ike's warning.

  9. Global Warming: Not Reversible, But Stoppable

    I note that Robin Hanson's 2001 prediction of doubling of GDP every 0.5 to 1.5 years by 2025 is actually pessimistic compared to his 1998 predictions of economic doubling times of mere days. Over a period of just three years he increased the economic doubling time by an order of magnitude or more. If his pessimism continued to increase geometrically, I would expect his GDP doubling time to be rather large by 2013. 

    I wonder what an appropriate discount rate would be if we lived in a world where the economy doubled in size every few days? I suspect that it would be so high that there would be no economic case to be made for dealing with any externality, no matter how bad, because we would all be so much better equipped to deal with it in a fortnight's time when we would all be much richer and happier. We can all look forward to those times when we can convince our spouses that there's no need to take the garbage out, because everything will be different next week.

    In such a world, even if you get the estimation of how much CO2 we need to sequester wrong by a factor of two, never mind, because we will have twice the means to deal with the problem in a few days' time.

    Robin Hanson,  in 1994, postulated that we will one day be living as disembodied  immortals in a virtual world:

    Fast uploads who want physical bodies that can keep up with their faster brains might use proportionally smaller bodies. For example, assume it takes 10^15 instructions per second and 10^15 fast memory bits to run a brain model at familiar speeds, and that upload brains could be built using nanomechanical computers and memory registers, as described in [Drexler]. If so, an approx. 7 mm. tall human-shaped body could have a brain that that fits in its brain cavity, keeps up with its approx. 260 times faster body motions, and consumes approx. 16 W of power. Such uploads would glow like Tinkerbell in air, or might live underwater to keep cool. Bigger slower bodies could run much cooler by using reversible computers [Hanson].

    Billions of such uploads could live and work in a single high-rise building, with roomy accommodations for all, if enough power and cooling were available. To avoid alienation, many uploads might find comfort by living among tiny familiar-looking trees, houses, etc., and living under an artificial sun that rises and sets approx. 260 times a day. Other uploads may reject the familiar and aggressively explore the new possibilities. For such tiny uploads, gravity would seem much weaker, higher sound pitches would be needed, and visual resolution of ordinary light might decline (in both angular and intensity terms).


    However in the real world, nearly twenty years later,  Robin Hanson is (presumably) still putting on his trousers one leg at a time.

    But just think about the consequences of living in a virtual world: our models would become indistinguishable from reality, there would be no telling the weather forecast from the weather itself!

    I actually enjoy reading Robin Hanson's blog Overcoming Bias from time to time. He is a smart guy and his posts there are often stimulating and they lead to enlightening but often bizarre discussions. For example, there is a post in which he compares malnutrition to involuntary celibacy and which leads to commenters earnestly asking whether rape is theft, or instead a fair redistribution of goods from the haves (eg George Clooney) to the rest of us have-nots, with all of our unfulfilled cravings. Readers from the everyday world, especially women and mature men, may well recognize that, despite the cleverness, there's something missing in such discussions.

    -----------------------

    More seriously, we inhabit a real world in which the Keeling Curve trends relentlessly upwards towards levels never before experienced by our superfamily of tailless primates. We humans, the most numerous in that family, find ourselves unable to arrest that rising trend, even as many of us accept that it could possibly lead to a planet that is largely uninhabitable. Let's not console or distract ourselves with crazy projections of a gilded future, one in which we will supposedly be able employ our infinite wealth to undo the damage we have done.

  10. empirical_bayes at 03:22 AM on 2 May 2013
    Roy Spencer's Catholic Online Climate Myths

    @Mark SB and @"Roy Spencer", regarding:

    "It does not seem likely to me that God would set up the world to work in such a way that human beings would eventually destroy the earth..."

    I've often thought that if such a Deity did participate in setting things up, the Deity did exactly what Spencer cannot believe.  The peak of the blackbody emissions from Earth's surface, determined by a temperature which is comfortable for much of life, is very close to that massive CO2 absorption region around 667 per cm. On the other hand, this could be seen as the delicate thermostat, carefully crafted, with idiotic human beings trampling all over it. 

    I personally don't buy the existence of such a Deity, but if Spencer invited the problem, he certainly has it. 

  11. Roy Spencer's Catholic Online Climate Myths

    Sadly, the "character arc" or "story arc" (if you will) that Dr Spencer is on appears to be the more typical one for scientific contrarians to take - and not just in climate science, but of various stripes (one thinks here of Dr Oz), where their positions become increasingly divergent from the reality presented by the evidence.

    The "story arc" where they realize that their positions are off-base and change them in response to the present state of the evidence (in other words, when they start behaving like skeptics) is sadly all too rare an occurrence.

  12. PhilBMorris at 01:53 AM on 2 May 2013
    Leave It in the Ground, Climate Activists Demand

    To base the future of humnaity - of the world as we currently know it on models that suggest 2 degrees would be safe but 3 degrees won't - is quite a gambol. 

    The global recession of 2008-2009 resulted in a 10% drop in CO2 emmisions, a drop that was compensated for by the subsequent 'recovery' in 2010-2011.  There's no likelihood whatsoever of there being massive cuts in CO2 emmisions without a significant and reliable source of energy to replace fossil fuels.  Solar and wind are not only intermittent but have their own environmental costs (toxic chemical waste) or are so land intensive as to be impractical for installations of adequate size.  Hydro is obviously limited geographically and also has massive environmental impact.  Uranium based nuclear power carries with it risks that are unacceptable.  Once can hope for a breakthough in fusion, but that breakthough has been waiting in the wings for well over 40 years now. 

    The only viable solution is a massive global investment in thorium based nuclear power, an energy source that would be reliable; have minimal enironmental impact; have no risk of meltdown associated with uranium based plants; do not produce weapons grade byproducts (Canadiam CANDU reactors burn weapons grade material in plants converted to use thorium as the fuel); and produce a volume of radiactive waste is a mere fraction of that produced by Uranium based plants. 

    Will we ever get there?  I for am am not hopeful!

  13. Roy Spencer's Catholic Online Climate Myths

    dana1981 - An additional part of that correction is that the deeper subsurface Antarctic waters are (relatively) warmer than surface waters, not colder as stated in the OP.

  14. Roy Spencer's Catholic Online Climate Myths

    Thanks KR - fixed.

  15. Roy Spencer's Catholic Online Climate Myths

    Regarding Antarctic sea ice expansion, according to Manabe et al 1991 (Part 1 of this set of papers), the cause is decreased mixing with deeper ocean layers, not increased as stated in the opening post. From Pg. 811:

    ...in response to the increase of atmospheric carbon dioxide, the excess of precipitation over evaporation increases, and surface salinity is reduced in high latitudes as noted in section 8. Thus, the static stability of the near-surface water increases and the convective mixing of cold surface water with the relatively warm subsurface water is reduced, thereby contributing to the reduction of sea surface temperature in the Circumpolar Ocean. This is why sea surface temperature hardly changes and sea ice slightly increases near the Antarctic Continent in response the increase of carbon dioxide.

    [Emphasis added]

    Reduced mixing with relatively warmer sub-surface waters effectively reduces the thermal mass exposed to the cold Antarctic air - slightly more ice forms. 

  16. Global Warming: Not Reversible, But Stoppable

    Mark Bahner @59 continues to live in an economic dream world! Who can blame him, it is a pleasant dream.  No doubt soon he will ask us all to step into a glass elevator.

    Meanwhile, back in reality, this is the pattern of economic growth over the last two millinia as J Bradford DeLong:

    (Source)

    The zero growth rate since 2000 is an artifact of a lack of data in that period.  The rest of the curve is real and is significant.  In particular, the decline in world economic growth from the 1950s and 1960s to the present day, as the world transitioned from vacuum tubes to silicon chips, is real.  While the information revolution has had a real and beneficial effect on the world economy, that has been more than countered by other factors, primarilly an increase in the cost of energy and the fact that resource exploitation was essentially global by the 1960s, so that further economic growth could only be achieved by accessing resources with a lower return on investment.

    For more recent data, here is the real growth in GWP from 1999-2011:

    (Source, accessed today)

    The effective growth real growth rate over that period turns out to be 3.5% per annum, although it would be slightly higher in PPP (Purchasing Power Parity) terms.  PPP growth in GWP from 2005-2012 is 3.6% per annum.

    Bahner's defence of his absurd growth rates now has two straws.  The first is simple mathturbation on the 50 year average growth rate over recent history, a calculation that does not factor in the clear slide in growth rates since the 1960s, and is falsified by them.  (Bahner actually throws out the results of his mathturbation as too conservative; and infates them artificially based on an assumption of the early achievement of full artificial intelligence; ie, his estimation proceedure has all the intellectual integrity of the classic "pick a number than double it" technique.)  The second straw is based on an article which overstates recent real growth rate, and assumes that the introduciton of AI is the golden goose of economics without actually plotting the course of economic growth durring the information revolution.  That is, it has no more intellectual credibility than Bahner's attempt, for all that the author is seeking to have it published.

    Moderator Response:

    [RH] Fixed image width.

  17. John Fisher at 19:18 PM on 1 May 2013
    Roy Spencer's Catholic Online Climate Myths

    Roy Spencer's endorsement of an open letter from the Cornwall Alliance in which it is stated "It does not seem likely to me that God would set up the world to work in such a way that human beings would eventually destroy the earth..." expresses his starting point perfectly, and therefore his answers will always be the same, regardless of actual data.

    Several familiar names here.

    http://en.wikipedia.org/wiki/Cornwall_Alliance

  18. Leave It in the Ground, Climate Activists Demand

    Doug, it is my belief that the 2 degree limit is chosen because we're reasonably sure the carbon cycle megafeedbacks (amazon desertification, permafrost decay, methane clathrate emissions) won't start in a big way. Stop at 2 degrees and we're reasonably sure the climate stays at 2 degrees. Stop at 3 degrees, and the climate system may go to 5 degrees on its own.

  19. Roy Spencer's Catholic Online Climate Myths

    Catholic Online would have done far better to interview Spencer about his membership of the Cornwall Alliance, which espouses the "greed gospel", and regards fossil fuels as part of God's bounty it would be an insult to pass up.

    http://climatecrocks.com/2012/11/30/right-wing-preacher-not-using-fossil-fuels-insults-god/

    Given the Papal positions on climae change and poverty, now that would have been an interesting interview.

  20. Climate Sensitivity Single Study Syndrome, Nic Lewis Edition

    Barry @35,

    You claim:

    "I often point out to people ('skeptics', usually) the error of relying on a single study, and most often it is with climate sensitivity estimates. It's good to see that caution explained here. I'm not trying to bait anyone."

    I'm open to the possibiity that there has been a misunderstanding on my part.  But the fact is that there are multiple, independent lines of evidence that still point to a best estimate of equilibrium climate sensitivity (ECS) near +3 C for doubling of CO2.  As far as the limitations of using the instrumented record to estimate ECS go, Dana happened to cite one study, but there are more.  For example, below is a quote from Knutti and Hegerl (2008) when referring to using the surface record and the climate's response to volcanic eruptions (such as Pinatubo) to estimate ECS [my bolding]:

    "The advantage of these methods is that they consider a state of the climate similar to today’s and use similar timescales of observations to the projections we are interested in, thus providing constraints on the overall feedbacks operating today. However, the distributions are wide and cannot exclude high sensitivities. The main reason is that it cannot be excluded that a strong aerosol forcing or a large ocean heat uptake might have hidden a strong greenhouse warming."

  21. Climate Sensitivity Single Study Syndrome, Nic Lewis Edition

    Nick's misrepresentation of the Aldrin et al. paper is egregious.  And make no mistake, it is a misrepresentation as Dana has shown and as I will again demonstrate below.

    Additionally, nowhere in AR4 or meta analysis papers on climate sensitivity (e.g., Knutti and Hegerl 2008) that I am aware of do they use the mode to quantify climate sensitivity. They use either the median and interquartile range or confidence intervals. It is quite the coincidence that Lewis managed to find the one value (of many) in Aldrin et al's extensive data analysis that fits his desired narrative for a lower climate sensitivity.

    Lewis could only obtain his desired number by using three cherry picks:

    1) Using the mode rather than median

    2) Ignoring Aldrin et al's higher sensitivity when including the indirect aerosol effect

    3) Ignoring Aldrin et al's even higher sensitivity when including the impacts of clouds

    Now including #2 and #3 above act to make the estimates more consistent and inline with processes the real world.  That is, higher.  Yet, Lewis decided to ignore those values... ;) 

    What Lewis has done is to cherry pick a particular scenario, then cherry pick a unconventional measure of climate sensitivity from Aldrin et al. (a value that Aldrin et al. did not even explicitly calculate or speak to anywhere in their paper) and then elevate it to front-and-centre in his abstract.

    Sorry, but the above actions reveal Lewis's bias/agenda. It would also be very disappointing if a prestigious journal like J. Climate were to turn a blind eye to such shenanigans. 

    PS:  As Barry noted at #37, Dana did edit the post based on Tom's recommendation. 

  22. Doug Hutcheson at 14:02 PM on 1 May 2013
    Leave It in the Ground, Climate Activists Demand

    they simply cannot be trusted with the future of our civilisation

    Sad, but oh, so true. Sadly, the imperatives of democracy do not include electors voting in a wise government, but a populist one. As long as the populace does not perceive the threat, it is not going to vote in favour of action.

  23. Leave It in the Ground, Climate Activists Demand

    Doug

    I am going to agree with you 100% about the dangers of even a 2 C rise in temperatures. But the advantage of this number is that it enables governments to do the maths on what they should and shouldn't do.

    Of course, the fact that they are failing to do the maths and do what is appropriate means that they simply cannot be trusted with the future of our civilisation.

     

  24. Mark Bahner at 13:19 PM on 1 May 2013
    Leave It in the Ground, Climate Activists Demand

    A moratorium on investments new fossil fuel infrastructure is the obvious thing to do about this, said Asad Rehman, head of international climate at Friends of the Earth in the UK.

    The United Nations is the place to get countries to begin a serious conversation about imposing such a moratorium starting Monday in Bonn, Germany, Rehman told IPS.

    Ho, ho, ho! Good one! But...this is May 1st, not April 1st?

  25. Doug Hutcheson at 13:03 PM on 1 May 2013
    Leave It in the Ground, Climate Activists Demand

    All nations have agreed under the UNFCCC to keep temperatures below two degrees C, which is by no means a safe level of warming. However, scientists say we are on a path to at least three degrees C, which will trigger irreversible feedbacks leading to much higher temperatures and far worse impacts.

    There's the rub: the 2° limit is an arbitrary, econopolitical construct, not a scientific one. The changes we are already seeing with 0.8°C are what I would call 'dangerous' and 2°C is, therefore, lunacy.

    Not that I am religious (I'm not), but is this the reason God got cross with Adam and Eve for eating the fruit of the tree of knowledge? Have we learnt just enough to destroy Eden? Homo Stupidus stupidus.

  26. Doug Hutcheson at 12:52 PM on 1 May 2013
    Forks in the Road: Last Exit to Two Degrees

    The figure shows this is truly the critical decade if we want to stay under 2 °C without an economically drastic whiplash of 5% decrease in emission per year.

    Stop the world, please - I want to get off before it crashes ...

  27. Mark Bahner at 12:51 PM on 1 May 2013
    Global Warming: Not Reversible, But Stoppable

    Your calculation for removal of CO2 is hopelessly optimistic.

    No, it's extremely pessimistic, because:

    1) It relies on IPCC economic growth projections, which will be shown within the next 1-2 decades to be far, far too low. They neglect the economic effects of artificial intelligence, which will be spectacular. Probably the best work in this area has been done by Robin Hanson. He uses a standard neoclassical (Solow-Swan) growth model to estimate annual ecomomic growth that could approach 45% per year (see page 6) by 2025. Needless to say, the IPCC does not have anything close to that.

    2) It assumes a cost of $1000 per metric tonne of CO2 removed. Humans have the rest of this century to get costs down, and I'm sure they will be well below that number when it is used.

    Regarding outgassing...approximately 50% of emissions have remained in the atmosphere for the last 3-5 decades. So even if all the CO2 that was previously absorbed gets re-emitted, the amount needing to be removed would simply double. So if the cost was down to $500 per metric tonne, my analysis would be completely intact. And if the IPCC scenarios have economic growth projections that are far too low (which they almost certainly do), then even with outgassing of all material, my estimates would be pessimistic.

  28. Doug Hutcheson at 12:44 PM on 1 May 2013
    New Research Shows Humans Causing More Strong Hurricanes

    the frequency of Katrina-magnitude storm surges doubles for every approximately 0.4°C average global surface warming

    That news, while not unexpected, is not good. No doubt, the denialosphere will ring with echoes of "We've reached saturation with Katrina-sized storms, so everything is alright". Sigh.

  29. New Research Shows Humans Causing More Strong Hurricanes

    DSL,

    I agree with you.  Sensationalism was not the best choice of words.  I should have used accurate. 

    Manwichstick,

    I think we are on the same page, but as a scientist I am picky about word usage. And, looking at it from a laymans point of view, the proper word usage cuts down on misunderstandings.  A lot of people only read headlines, and if you only read this headline then you are going to have a misconception that this paper is definitive.  It certainly adds to the body of evidence, but the authors own phrasing should be presented.

  30. Forks in the Road: Last Exit to Two Degrees

    I have to say, that cartoon by John Garrett is pretty awesome.  Well done.

  31. Forks in the Road: Last Exit to Two Degrees

    Curiously, a few years back Canadian expatriate writer Gwynne Dyer wrote a column along a similar vein, called "Last Exit to the Holocene".

    Bottom line, then and now: if you want to live in the more-or-less stable climate which enabled human agriculture (and hence the comfortable, materially affluent civilization I daresay most of us prefer to live in), time to get cutting down on emissions.

  32. Dikran Marsupial at 04:00 AM on 1 May 2013
    Nils-Axel Mörner is Wrong About Sea Level Rise

    By the way, this isn't the first time Morner has done this sort of thing, see for example here and here.

  33. Dikran Marsupial at 02:07 AM on 1 May 2013
    Nils-Axel Mörner is Wrong About Sea Level Rise

    I'd just like to second what Philippe says, nice work indeed Tom, checking the details is hard work, and normally a pretty thankless task, but very important. 

    I also think it would be worth submitting a comment to the journal, fewer bad papers would be submitted if more people wrote comments papers.  This doesn't matter in science as the few bad papers that get through peer review are just ignored by the scientists, but papers in climatology also generate interest in the general public, who are less able to tell the wheat from the chaff, so the importance of comments papers is much greater.

    I note the journal in question requests the author to provide the names of five people who could review the paper.  I really wish journals didn't do this, a good journal should have sufficiently able action editors that are familiar with the field and can identify suitable reviewers themselves.  It seems to me to be a recipe for a failure of the peer-review process if you can choose freindly reviewers.

  34. Philippe Chantreau at 00:41 AM on 1 May 2013
    Nils-Axel Mörner is Wrong About Sea Level Rise

    Nice work Tom, as always. You should send a comment to the journal. Perhaps they are just in the business of selling "peer review" rubber stamping and they won't care, but then again, perhaps they will publish the comment.

  35. Manwichstick at 00:14 AM on 1 May 2013
    New Research Shows Humans Causing More Strong Hurricanes

    Terranova, I see your point, but after I've thought about it, I don't have a problem with the title for two reasons.

    1) it briefly summarizes what the two articles suggest

    2) "New Research Shows..." as a statement, should never be assumed to be a proven fact. I know the public thinks this way (if they are inclined agree with the premise), but I think we should do a better job of educating the public that "new research shows..." should be interpreted as "more evidence has been collected to viewed in the light of what has already been learned and should be put in context by experts in the field before we determine, what conclusions might be drawn".

    When I hear "new research shows..." I try think "That's interesting," and try to avoid a reflex of such as, "Take that! - Hurricane Sandy wasn't influenced by global warming deniers!"

    I want to encourage people to react a little more cerebral: "Hmmm, does this fit into our best understanding of how climate works? Do I need to re-think anything? What are the limitations of these studies? " and so on...

  36. New Research Shows Humans Causing More Strong Hurricanes

    While I agree with your overall point, TerraNova, I think it's a little sensationalist to label the title "sensationalism."  It would need at least one exclamation point, and it would need at least one exaggeration.  It's well within the realm of possible (it's even likely) that human emissions are the root cause of the recent likely upswing in storm surge.

  37. michael sweet at 20:17 PM on 30 April 2013
    Global Warming: Not Reversible, But Stoppable

    Mark,

    Your calculation for removal of CO2 is hopelessly optimistic.  If you start to remove CO2 from the atmosphere then the ocean will begin to outgas CO2 instead of absorbing it.  This means you have to remove much more CO2 to lower the atmospheric level than you estimate.  Provide citations for your wild claims about how much carbon needs to be removed to lower atmospheric CO2.

    Invariably the geoengineering people leave out half of the problem to make their proposals look good.

  38. New Research Shows Humans Causing More Strong Hurricanes

    Dana,

    Your headline should be reworded to at least include either of the words "suggest" or "may" to better reflect the body of your post.  Your headline appears to make a statement as if it is proven fact.  Even the authors use less certain qualifiers.  As a reporter, sensationalism may be par for the course, but as a scientist it should not be.   

  39. Global Warming: Not Reversible, But Stoppable

    John Hartz - Thank you for the very relevant reference. They discuss in particular one of the lowest cost CO2 removal schemes, biological drawdown:

    Although there is large uncertainty about sustainable levels of bioenergy use (...), it can be expected that sustainability constraints will limit the use of BECCS [Bio-energy with carbon capture and storage] as CDR [Carbon dioxide removal] technology. In our analysis, BECCS deployment is effectively limited to a removal of 14–15 GtCO2 per year.

    That works out to ~2 ppm/year, or roughly the rate of current emissions. Given the 550 ppm Mark Bahner discusses, that means 225 years of BECSS drawdown assuming no further emissions - with that drawdown competing with food production, and with its own energy/resource costs (including fresh water and soil nutrients that will be consumed in the process). 

    It might be a helpful addition to mitigation, but again - CO2 removal is no panacea. And even that (relatively) low cost sequestration is still more expensive than mitigation. 

  40. Nils-Axel Mörner is Wrong About Sea Level Rise

    An update to my post @48:

    1)  I have tracked down the source of Morner's claim that the ABSLMP shows a 5.4 mm per year sea level rise.  If you take the average of the raw trends of all 16 AMSLMP stations from their time of construction to June 2011, it is 5.37 mm/year.  These are the trends before any adjustment for local changes in height of the equipment relative to surveyor's datum points, and before reverse barometric adjustments.

    The Australian Bureau of Meteorology reported these figures in their 2011 report, but then reported the size of the adjustments and the final adjusted figures.  It is hypocritical of Morner to ignore those adjusted figures and then to criticize the BOM for not accounting for subsidence and/or the effects of ENSO (ie, barometric effects).

    2)  I have managed to track down the source of the data, and which data he selected in making his comparisons.  Specifically, in addition to the 16 SEAFRAME (ABSLMP) sites, he uses the metric sea level data from the Permanant Service for Mean Sea Level (PSMSL).  He only uses sites which continue significantly past 1990, or where two very close sites can be used to provide a significant record extending past 1990.  I was able to determine this by looking at his Figure 1, and noting the four sites he shows in the immediate vicinity of Port Philip Bay (Melbourne).  There are not four Revised Local Reference (RLR) records in that vicinity, ergo he must have used the metric data.

    The key about using metric data is that it has not been adjusted to account for any local vertical movements of the tide guage.  In contrast, RLR records are adjusted to a standard height datum and so adjust for any purely local subsidences or uplifting of the tide guage.  (They do not account for changes resulting from subsidence or uplift of contintental plates, as near as I can determine.)  Because metric data does not account for local land movements, it is considered highly suspect.  The PSMSL state:

    "Without the provision of full benchmark datum history information, records generally remain as 'Metric only' in the databank and not as 'RLR'. In general, 'Metric' records should NEVER be used for time series analysis or for the computation of secular trends. Without datum continuity their only use is in studies of the seasonal cycle of mean sea level. If there is any doubt about the datums for a particular record, the PSMSL would be pleased to supply clarification."

    Of course, Morner has used those metric records so do exactly what the PSMSL has said you should never do, ie, compute a secular trend.  He has gone on to criticize the RLR (ie, height datum adjusted) data from the SEAFRAMES because it disagrees with the the data for which he has no record of local relative height movements.  This is the sort of gall I would expect from the man who published a photoshopped picture as "evidence" in a purportedlyh scientific paper.

    3)  Morner's figure 3 is a mishmash of different sorts of data.  His 5.4 mm trend that he claims is reported by ABSLMP2011 is the metric version, as are his various Australian (2a, b and c) and World (3 a and b) tide guage records and are not comparable because of the effects of local land movements.  In contrast, Church and White and the Topex/Jason satellite record are independant of local land movements, and have a reverse barometric adjustment and hence are comparable to the 4.3 mm year mean trend of the SEAFRAME tide guages.  The suggested discrepancy between the SEAFRAME data and the satellite data is, however spurious on another ground.  Specifically, the satellite data is not taken over the same period or the area.

    Fortunately the ABSLMP2011 report shows the Topex/Jason trend from Dec 1992 to March 2011 (Fig 17).  I have adapted that image by showing the approximately location of the ABSLMP sites, and their trend from construction to June 2011.  The later was shown by colour picking from the location indicated by their trend on the index bar, and flooding their square with that colour so direct colour comparison gives a good idea of the relative trends:

    As can be seen, the only significant disagreement is at Hillarys near Perth (SW Western Australia).  As it happens, the highest, second, highest, and fourth highest months on record occured between March and June 2011, the addition of which of which wold largely account for the discrepancy between satellite and tide guage records.  Curiously, Morner commented extensively on the nearby Fremantle tide gauge record, but truncated his analysis prior to that notable surge in local sea levels (also visible in the Fremantle data).  The difference at Hillarys between sea level trends to June 2010 and June 2011 is 1.6 mm/year.  Adjusting the Hillarys trend down by that amount probably better reflects the time parity with the satellite record shown, and adjusts the trend to 7.4 mm/year (yellowy orange).  There remains a small discrepancy, as also at Port Kembla in the reverse direction.  Overall the satelite record tends to confirm the accuracy of the SEAFRAME data, and clearly refutes cliaimed overall Australian trends of 0.1 to 1.5 mm per year as made by Morner.

    4)  I previously mentioned the geographical bias of Morner's additional stations.  They come almost exclusively from the east and south east coasts with their low sea level rises.  The extent of the bias is shown in the figure below:

    The area highlighted represents over 50% of the Australian coastline.  As shown, the ABSLMP has 7 of 16 SEAFRAMES in that area, representing a slight East Coast bias.  That bias is not consequential because the ABSLMP do not report a national average (for a reason).  Morner, how does report a national average, increases the bias with his 36 station long records, and still further with his full 86 station count. In all, the most rapidly rising sea levels around the Australian Coast are represented by just 26% of Morners tidal guages.  Despite this he purports that a simple mean of the stations will show the sea level rise around Australian coasts.

    5)  Much of Morner's criticism of the ABSLMP is based on the idea that twenty years is far to short a time to determine long term trends.  (Despite that, he purports to find a significant five year trend in the Fremantle data, showing he is nothing if not inconsistent.)  However, as a criticism of the ABSLMP, this is distinctly a straw man.  They have this to say on the subject (in ABSLMP 2011):

    "It is important to emphasise that as the ABSLMP sea level records increase in length, the sea level trend estimates will continue to stabilise and become more indicative of longerterm changes. Caution must be exercised in interpreting the ‘short-term’ relative sea level trends (Table 2) as they are based on short records in climate terms and are still undergoing large year-to-year changes."

    (My emphasis)

    In essence, Morner has taken the AMSLMP's own caution and expanded it, incompetently, into a "scientific" paper, taking care all the time to not mention the ABSLMP's original caveate.

    It is no wonder he made sure to publish the paper in as obscure a journal as he could.

  41. Global Warming: Not Reversible, But Stoppable

    Responding to Mark Bahmer's various posts:

    Assuming a continuation of the average economic growth durring the post war boom years of 3% per annum, the global economy will have grown to thirteen times its current value.  In contrast, the IPCC estimate of 25 times the 2007 value requires as sustained growth rate of 3.5%.  Growth of a hundred fold requires an economic growth rate of 5.4% per annum, a figure not achieved for global growth since 1973 and extraordinarilly unlikely to be achieved as a global average over a century, even absent any negative effects from global warming:

    (Wikipedia)

    Consequently the IPCC estimate is at least plausible, if a bit opitimistic.  Yours are definitely over optimistic.

    What is more, the standard assumption that you can increase CO2 in the atmosphere by 300 ppmv with no harmfull effects on economic growth is just bizzare.  A certain consequense of such an increase is the loss of Arctic summer sea ice.  An almost certain effect of such an increase will be the destruction of the great barrier reef.  Another probable consequence will be the conversion of Amazon rainforest into a system of open forest and savannah.  These large scale ecological catastrophes must inevitably have adverse effects on the human economy, and those effects will show up as reduced growth.  In the latter half of this century, the economic issue is not whether we will be achieving 3% of 5.4% growth of the global economy, but whether we can avoid 3% to 5.4% contractions of the global economy, year in and year out.

    Regardless of whether or not you consider the risk of a contracting global economy in the later 21st century with ongoing global warming to be real (and only the very foolish or thoughtless will dismiss that possibility out of hand), the fact remains that extra CO2 in the atmosphere has a cost.  Consequently, if the cost of not emiting the CO2 equals the cost of removing it later; it is better to not emit it because it avoids that cost.

    In addition to not taking into account the costs of increased CO2 concentrations (both to economic growth and as a raw cost), you fail to take into account the fact that various schemes to draw down CO2 from the atmosphere have an ecological impact as well.  Simply framing it in terms of dollar values ignores half of the costs.

  42. Global Warming: Not Reversible, But Stoppable

    KR #53: In my previous comment I mistyped - it should state "the world economy increases by a factor of 100x", not 1000x, to match Mark Bahner's post.

    By comparison, the most agressive SRES emissions scenario (A1T) used in IPCC predictions of GHG levels indicates a maximum world GDP growth of only ~25x by 2100,...

    OK, let's use the IPCC's numbers. Their economic growth numbers are very likely to be proven extremely wrong on the low side:

    Third thoughts on economic growth in the 21st century

    ...but let's assume the economy grows by only a factor of 25 in the next 100 years. That means in the year 2113, it will be possible to remove 25 ppm of CO2 per year for an expenditure of 10 percent of the world GDP. (Since we now can remove 1 ppm for an expenditure of 10 percent of the world GDP...assuming $1000 per ton of CO2, which is probably too high, especially for 100 years from now.)

    The concentration under the A1T scenario is projected to be about 900 ppm in 2113. Let's say they want to get down to 350 ppm. That would be a reduction of 550 ppm. At 25 ppm per year, they could get there in 22 years.

    So once again, the Matthews and Solomon paper is based on a completely indefensible premise. They claim that global warming is "irreversible" over multi-century time frames (in fact 1000 years). This neglects the economic growth that's likely to happen even in the next 100 years (let alone the next 200+ years).

  43. Global Warming: Not Reversible, But Stoppable

    @KR #52 & #53:

    Suggest that you check out: Kriegler, E., Edenhofer, O., Reuster, L., Luderer, G., Klein, D. (2013): Is atmospheric carbon dioxide removal a game changer for climate change mitigation?Climatic Change (online) [10.1007/s10584-012-0681-4]

    I believe it bears directly on your ongoing dialogue with Mark Bahner. 

  44. Global Warming: Not Reversible, But Stoppable

    In my previous comment I mistyped - it should state "the world economy increases by a factor of 100x", not 1000x, to match Mark Bahner's post.

    By comparison, the most agressive SRES emissions scenario (A1T) used in IPCC predictions of GHG levels indicates a maximum world GDP growth of only ~25x by 2100, with the lower emissions scenarios ranging from 11-16x. Those are based on quite reasonable assumptions and prior experience with the GDP growth of developing countries - I don't believe that 100x GDP growth by 2100 is even in the realm of possibilities. If it was possible, it would almost inevitably be accompanied by even more emissions, making a carbon capture approach more challenging. 

    Again, it seems to me that carbon capture is not a panacea, and that BAU is by far the more expensive path. Mitigation, emitting less to start with, is far less expensive than adaptation. 

  45. Global Warming: Not Reversible, But Stoppable

    Mark Bahner - An interesting speculation. However, beyond hoping (1) the world economy increases by a factor of 1000x, and that (2) less than $1000/ton CO2 removal is achievable, this approach has more than a few issues. 

    First - the non-trivial cost of such removal invalidates Sarawitz and Pielke's major premise, that:

    Unlike abandoning fossil energy, capturing carbon does not demand a radical alteration of national economies, global trade, or personal lifestyles.

    10% of world GDP is a major hit. WWII in the US, which you use as an exemplar, required energy rationing, intrusive government control of all sectors of the economy, material substitution due to war needs, and so on. I would consider those radical alterations

    Second, the idea of forever continuing the use of fossil fuels hits the limits of just how many reserves are present, and how much exploiting marginal sources will cost. Not to mention making carbon removal a permanent and repeating cost to the economy, whereas moving to a non-fossil fuel basis removes both the carbon problem and the need for the removal at the same time. 

    Finally - carbon removal takes energy. Using a fossil fuel source is a net loss - entropy is a bear, and a fossil fuel based carbon removal to, as S&P suggest, produce new fuels, will inevitably produce a net increase in CO2. Non-fossil fuel power sources are required for a net gain, for a drawdown in CO2. 

    ---

    Face it - Just about every study made shows that mitigation, moving from a fossil fuel economy to one that isn't, will be far less expensive and altering of our lifestyles than adaptation, such as dumping CO2 we don't need to and then trying to remove it later. 

    Given the disparity in costs between mitigation and adaptation, these cries of economic hardship over mitigation are beyond silly. Business As Usual (BAU) with continued use of fossil fuels is the more expensive path, the one that will engender more hardship, more radical alteration of lifestyles. I find it just incredibly sad that those complaining most about the idea of mitigation are loudly beating the drums for a path that will actually cost us far more, and be more of a burden on rich and poor alike...

  46. Rob Honeycutt at 03:35 AM on 30 April 2013
    Global Warming: Not Reversible, But Stoppable

    Honestly, if they could actually develop and scale the technologies to remove CO2 from the open air (huge if in that), then fine.  More power to them.  But the cost of removing the CO2 absolutely must be borne by the emitters themselves.  It should not be borne by the public at large.

    Now, tell me if you think the fossil fuel industry would agree to such terms.

  47. Announcement: New Guardian Blog by Dana Nuccitelli and John Abraham

    Perma-irony?

  48. Rob Honeycutt at 03:26 AM on 30 April 2013
    Global Warming: Not Reversible, But Stoppable

    Mark...  I find it fascinating how the article you link states that "...a shift to carbon-free energy remains the Platonic ideal" whereas there are, very clearly, existing and fully developed technologies to do this.  The rate of growth in solar and wind are much greater than that of other FF energy sources.  And, there are currently no – exactly zero – CCS power plants currently operating (AFAIK).

    It seems to me the "Platonic ideal" is completely opposite to what the article reports, which is not unusual, given that it comes from Roger Pielke Jr.

  49. Global Warming: Not Reversible, But Stoppable

    Rob Honeycutt:

    "Mark Bahner... Aren't you ignoring the fact that the relative cost of removing the CO2 would also rise with the growth of the world economy?"

    No, I'm ignoring the fact that the cost of removing a metric ton of CO2 would likely fall with the growth of the world economy. That is, what might cost $1000 per metric ton to remove in 2013, will likely fall to a small fraction of that, as humans learn how to do it more efficiently.

    Oops. Lunchtime is over. :-( I'll try to address your other comments later tonight or tomorrow.

  50. Rob Honeycutt at 02:53 AM on 30 April 2013
    Global Warming: Not Reversible, But Stoppable

    Mark Bahner...  Aren't you ignoring the fact that the relative cost of removing the CO2 would also rise with the growth of the world economy?  And at the same time, you have CO2 emissions continuing to rise, so can you actually remove CO2 as fast as you're adding it?  And why not just skip that entire process and just not put it into the atmosphere in the first place?

    If the cost of removing it is $1000 per ton, why not just tack on, say, 10% of that same cost ($100/ton) as a tax on carbon emissions, as a tax and dividend plan, then the economic impact would be negligable at worst, and potentially would fuel very rapid, and economically beneficial, technological development.

    And hey, let's not wait.  If the issue is that we're going to have to pull those CO2 concentrations down, add that $100/ton tax today.  That would clearly be the most economically advantageous course of action, bar none.

Prev  912  913  914  915  916  917  918  919  920  921  922  923  924  925  926  927  Next



The Consensus Project Website

THE ESCALATOR

(free to republish)


© Copyright 2024 John Cook
Home | Translations | About Us | Privacy | Contact Us