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  929  930  931  932  933  934  935  936  937  938  939  940  941  942  943  944  Next

Comments 46801 to 46850:

  1. Making Sense of Sensitivity … and Keeping It in Perspective

    Elsa,

    The relationship between CO2 and temperature is:

    ∆T = K log2(CO2final/CO2initial)

    The derivation of the equation is non-trivial.  Asking for it is like asking me to explain the theory of relativity to you.  However... it is accepted by everyone except for the nuttiest of deniers.

    If you are arguing something that basic, you are hopeless, and everyone is wasting time with you.

  2. Making Sense of Sensitivity … and Keeping It in Perspective

    Elsa:

    Your request for a "single" equation linking CO2 and global temperature is sort of like asking for the single equation that shows that a Boeing 787 can fly, or the single equation that relates total US tax revenues to personal income.

    ...but for a starting point, if you want to question that CO2 absorbs IR radiation, perhaps you can ask the people at Licor that sell off-the-shelf IR gas analyzers that use IR to measure atmospheric CO2 concentrations for the equations they use. This is stuff that is old hat.

    Moderator Response: [DB] Added link.
  3. A Detailed Look at Renewable Baseload Energy

    Interesting though this discussion is, I wonder whther the big picture is being lost. When you look at the projections below (OK they are by an oil company PDF but let's assume that they are not that bad), renewables and nuclear gow over the twenty years, but nowhere as much in absolute terms as coal, gas or oil. OECD countries show little growth in energy and all the growth and, by 2030, two-thirds of the consumption will be in developing countries. Debating the relative merits of renewables vs nuclear in OECD countries seems rather beside the point when the forecasters are predicting negligible shares of both sources globally and quite massive increases in fossil fuel consumption. Shouldn't we be rooting for bigger shares for both nuclear and renewables?

  4. It's not bad

    KenD:

    Instead of looking at the next 20 years, why don't you dig up some predictions made in the past - e.g., Arrhenius in 1896 - that have come true?

  5. Making Sense of Sensitivity … and Keeping It in Perspective

    elsa:

    If you are sincere in your quest for equations, you should trek on over to the Science of Doom website and peruse the post, Atmospheric Radiation and the “Greenhouse” Effect.

  6. Making Sense of Sensitivity … and Keeping It in Perspective

    Elsa,

    Stripped of its niceties you seem to say that the models are not derived from physics, but from measurements. But if that is the case they are not testing a theory at all. They are fitting (or tuning as you put it) the data to the theory so of course they will appear to work.


    The measurements referred to are of how CO2 (and other gases) absorb radiation in the atmosphere. The physics of climate models are based on these measurements. You said there was no physical link to CO2 and temperature in climate models:

    Yes people have looked at actual temperature and CO2 concentrations but that does not supply an equation linking the two derived from physics.

    The information provided you is the 'link' you think is missing - and that is only a fraction of the work done on the very matter you assume is 'missing'. Read the papers I linked above and see for yourself.

    Of course GCMs are based on empirical data. If you think that scientific theories must operate without using actual data, then you have an unbelievably misbegotten notion of science.

    Your assertion was that models are fit to temperature data. You are entirely, utterly and completely wrong about that. They are based on the physics of climate processes. They are not tuned to temperatures.

    No insult intended - you are very ill-informed on these matters. Check out the links, learn more about it, and try here again after that.

     

    Moderator Response: [DB] It is clear that in the 2 years and 7 months that have elapsed that elsa has not taken the time to actually learn something about the climate models, choosing instead to remain thoroughly uninformed about them.
  7. Making Sense of Sensitivity … and Keeping It in Perspective

    I just wrote this comment to the Economist article. Do fellow SKS'sers think it's a good point?

    ______________________________________________________________

    Perhaps the writer of this article ought to have done a bit of thinking before writing this misleading article.

    They portray the lower estimates of climate sensitivity, from a few researchers (around 1.9-2.0°C per CO2 doubling), as being somehow "safe" because this makes some hope that we could probably handle that amount of warming.

    Like many people trying to make the sceptical/denialist case, they do not think it through. If the policy makers of the world thought such a value of sensitivity was "safe", what do you think would happen? There would be few, if any, attempts to reduce emissions, so atmospheric levels of CO2 would carry on rising faster.

    Here's a question for the sceptics - what makes you think levels would stop just at a doubled value from pre-industrial times (280 -> 560ppm)? Why would humanity not, in due course, double that again to 1120 ppm which would lead, even using the rose tinted "get out of jail free" sensitivity of 2°C, to 4°C of warming, which no one sane can dispute would be highly dangerous.

    To those who don't think we could get to 1120ppm with just our fossil fuel, fracked gas, tars sands etc remember that the Arctic is warming a lot more than most and there is a lot of tundra/permafrost up there already starting to melt, which will be releasing large amounts of CO2 as the frozen organic material decomposes. Not to mention the increased out-gassing of CO2 from the oceans as they warm too.

    So, even if these lower sensitivity figures are valid, we are still facing a very dangerous situation and articles such as this one, that try to make out we are not, are reckless and irresponsible.

  8. Making Sense of Sensitivity … and Keeping It in Perspective

    Elsa,

    Since you ask me "to get down to tin tacks" I will. I see no reason to believe that a doubling of the concentration of CO2 (from one very low figure to another slightly higher but still very low one) will result in a temperature change of very much.

    No reason to believe? But where does your doubt take you? Do you investigate your own assumption?

    Human industry has added 100 parts per million of CO2 to the body of the atmosphere. Would you happily swallow 100 ppm of your body weight in cyanide, believing that such a small amount will have negligible effects? I would suggest more study before you attempt to demonstrate why tiny amounts of something must perforce be of little consequence.

    There is a massive dent in the ozone layer the size of Australia over the South Pole from a few hundred parts per billion increase of ozone depleting gases in the atmosphere. The process is different (catalytic), but the point is the same.

    Rather than scale, investigate the power of CO2 as a greenhouse gas. It is a tiny fraction of the atmospheric composition, 0.039%, but GHGs, which, increase the surface temperature by 33C, comprise only a small part of the atmospheric total of gases. The effect of CO2 in terms of greenhouse forcing is relative to its proportion in the total of greenhouse gases and its particular power power as a greenhouse gas (different gases have different absorptive power). Its contribution is calculated to be somewhere between 9 and 20% of the greenhouse effect.

    Greenhouse_gas#Impact_of_a_given_gas_on_the_overall_greenhouse_effect

    If wikipedia is not enough for you, you can refer to the science papers I linked above  (Ramanathan & Coakley (1978), the ones linked at the wiki page, (eg, this one) and have a rummage in google scholar.

    Don't wait for your lack of belief to inform you. Apply any curioisity you may have.

    Moderator Response: [RH] Shortened link that was breaking page format.
  9. Making Sense of Sensitivity … and Keeping It in Perspective

    Barry

    Thank you for your comment.  Stripped of its niceties you seem to say that the models are not derived from physics, but from measurements.  But if that is the case they are not testing a theory at all.  They are  fitting (or tuning as you put it) the data to the theory so of course they will appear to work.

  10. Making Sense of Sensitivity … and Keeping It in Perspective

    Sphaerica

    Perhaps, since you say that the link between CO2 and temperature is derived from physics, you can tell us what the equation is that links the two and how it is derived?

  11. Making Sense of Sensitivity … and Keeping It in Perspective

    Elsa,

    With regard to the physical process you have not addressed the point. Yes people have looked at actual temperature and CO2 concentrations but that does not supply an equation linking the two derived from physics. All it is doing (and the models likewise) is fitting the data to the theory.

    The models are sets of equations. They are not fit to observations of temperature. They are tuned to emulate certain processes, but not trends. The physics of infrared absoprption of greenhouse gases is derived from empirical measurements, which are the spine of climate models. The impatience you are reading above probably comes from the fact that this information is basic to an understanding of models, and your views are very under-informed.

    The following paper is one of the seminal calculations of the atmospheric greenpouse effect, from 1978.

    Ramanathan_Coakley_Radiative_Convection

    which builds on the work of papers like this

    ftp://eos.atmos.washington.edu/pub/breth/CPT/manabe-wetherald_jas67.pdf

    HITRAN is an empirical database of the absorptive and tranmissive properties of gases in the atmosphere. These data underpin atmospheric models.

    realclimate have a couple of simple FAQs on climate models, worth reading to get some basic understanding.

    http://www.realclimate.org/index.php/archives/2008/11/faq-on-climate-models/

    www.realclimate.org/index.php/archives/2009/01/faq-on-climate-models-part-ii/

    Models attempt to replicate the physics of the climate, and variables are perturbed (like increasing CO2) to calculate what the resulting changes might be. They are not fit to temperature data.

    Moderator Response: [RH] Shortened link that was breaking page format.
  12. Making Sense of Sensitivity … and Keeping It in Perspective

    scaddenp Since you ask me "to get down to tin tacks" I will.  I see no reason to believe that a doubling of the concentration of CO2 (from one very low figure to another slightly higher but still very low one) will result in a temperature change of very much.  You mention of 3.7W/m2 without explaining where this number is derived from.  Perhaps you can tell us why this particular one is right?

  13. It's not bad

    Thanks for your helpful responses, DSL, Sphaerica, and Dikran. I'll see if one of my friends is willing to make a wager on the following, assuming we stay at or above current C02 levels (just shy of 400 ppm):

    If total ice sheet loss over the next 10 years is less than 3.44 trillion tons (344 billion tons times 10 years), then he wins and I lose.

    If Arctic sea ice is > 250k km2 area in 2023 at summer minimum, then he wins and I lose.

    The friend I'm thinking of is a fan of WattsUpWithThat, so I'm hopeful he'd be willing to bet on the above. I'm assuming these are pretty safe bets on my part?

  14. Pierre-Normand at 08:53 AM on 30 March 2013
    Earth Encounters Giant Speed Bump on the Road to Higher Sea Level

    Thas's true, rob. NASA JPL coined the terms. But they also clearly meant the "speed bump" to represent a slow down in the rate of sea level rise and the "pot hole" to be an extreme case of a "speed bump", that is, an actual reversal of the sign of the trend. Whereas you use the term "speed bump" to refer to the recent sharp increase in the rate of sea level rise. This is queer and rather contrary to common usage. I didn't object to the very use of the metaphor. But it's just a quibble.

    Of course, I agree with Bob on both counts.

  15. Earth Encounters Giant Speed Bump on the Road to Higher Sea Level

    Pierre-Normand:

    Given that the analogy is "potholes and speed bumps", both are reasons to slow down a vehicle on a road. They represent irregularities - one where the observations are lower than a smooth ride, and one where observations are higher than a smooth ride. Neither is necessarily related to the long-term trend of the altitude (slope) of the road.

  16. Making Sense of Sensitivity … and Keeping It in Perspective

    elsa:

    Rob Painting reminds me of an analogy I proposed some time ago to explain the irrelevance of the smallness of the concentration of greenhouse gases (GHGs).

    Think of a city square where a politician is to give a talk. Many people are there to listen; but a handful have been hired by his opponents, to assassinate him. How will the likelihood of their success depend on their relative proportions?

    Basically, the more assassins there are, the greater the likelihood that one of them gets him: one or two assassins could easily be stopped by the Secret Service, but if there are a lot of them, it's much more likely someone will get a shot.

    How will this be affected by the number of non-assassins? Basically, not at all: non-assassins are not there to protect the politician, they are just there to listen. They will not be looking for trouble. They are irrelevant.

    Therefore, to first order, the likelihood of success by the assassins will be the same if they represent 100% of the attendees as if they represent 1/100-% of the attendees. (In fact, in a slightly more realistic case, the more non-assassins there are, the more distracted the Secret Service will be; so the chances of assassination increase as the proportion of assassins drops.)

    Now think of the politician as being the infrared photon, the assassins as being the greenhouse gas molecules, and the non-assassins as being the non-greenhouse-gas molecules. In the same way, the proportion of GHG molecules is to 1st order irrelevant to the GHG capability; and, due to pressure broadening, if the number of non-GHG molecules is increased, the GHG capability even increases.

    You just have to have enough GHG molecules in absolute number.

  17. Earth Encounters Giant Speed Bump on the Road to Higher Sea Level

    Pierre-Normand - The gals and guys at NASA JPL came up with that. I think it's a nice simple way to convey the message. Especially when we consider that the majority of Earth's population do not know anything about sea level rise. YMMV.

  18. Pierre-Normand at 07:23 AM on 30 March 2013
    Earth Encounters Giant Speed Bump on the Road to Higher Sea Level

    This is a very nice article. I just have a quibble. To my ear, the metaphor of a speed bump in sea level rise stongly suggests a cause for a temporary reduction in the rate of increase. Speed bumbs are designed to force motorists to slow down. But you mean the metaphor just to be heard as a pictural representation of the shape of the sea level function in the vicinity of a local maximum. Googling the phrase "speed bump on the road to..." only seems to return uses that are opposite to the intended meaning of your title. For instance:

    "Comparison—A Speed Bump On the Road To Happiness & Simple Living. “Comparison is the death of joy.” ~Mark Twain."

    "It's expected to be a fiscal speed-bump on the road to economic recovery that is otherwise looking good."

    etc.

  19. Earth Encounters Giant Speed Bump on the Road to Higher Sea Level

    Michael Sweet - Not sure about AVISO updates, I check back there periodically. Maybe every 8 weeks? 

  20. Earth Encounters Giant Speed Bump on the Road to Higher Sea Level

    GCNP58 - I've not run across scientific papers that address this directly. They may exist but I haven't stumbled across them. But nevertheless, this intensified sea level variation coupled to ENSO is implied from climate model simulations in a process known as the intensification of the global water (hydrological) cycle. This is something observed to be well underway, but where observations suggest actual changes are twice that projected by climate models (Durack [2012]). La Nina and El Nino represent extremes in the global weather, so it's where we should expect to see this water cycle intensification (eventually at least).

    I would not anticipate that any of the models project the kind of behaviour we have observed recently. The water cycle intensification is more a gradual one in the simulations - even allowing for the greater-than-modelled water cycle observations. It could be that some component, or components, are missing from the models. But then again this could just be some (as yet not understood) aberration and we see a return to smaller multi-year variation.

    Another consideration are the continental drainage basins of the Northern Hemisphere. Some of these were once frozen solid, but some have now thawed with global warming and may be starting to contribute to continental storage and drainage of water.

    The problem with all of this is that the global observations of these quantities is not robust, and the uncertainty in measurements is large. The reconstructions of global sea level throughout the 20th century are quite varied, which indicates the difficulty. Teasing even weaker signals out of the data is going to take some work.I just thought it useful to point out that there is a scientific expectation that ENSO-related sea level change will grow more variable at the planet gets warmer, and the weather more extreme. Something many readers are perhaps unaware of.

    SkS will have more on this in the future. 

  21. Christopher Gyles at 06:52 AM on 30 March 2013
    Making Sense of Sensitivity … and Keeping It in Perspective

    Question: inasmuch as the ocean, especially the deep ocean, has recently been accumulating heat at a faster than "average" rate due to ENSO variables, do climate sensitivity estimates include factors such as theoretical tipping points, e.g. abrupt methane releases from clathrates? If not, why not?

  22. Earth Encounters Giant Speed Bump on the Road to Higher Sea Level

    michael sweet at 05:09 AM on 30 March, 2013

    Like Horatio Algeranon said elsewhere:

    Warming never starts

    It only ever stops

    Though lower in the past

    The temperature always drops.

  23. Making Sense of Sensitivity … and Keeping It in Perspective

    Elsa, lets get done to tin tacks here. Do you dispute that doubling of CO2 will result in a radiation forcing of 3.7W/m2? Or are you claiming that 3.7W/m2 of extra energy is insignificant?

  24. It's not bad

    KenD,

    20 years is too short of a time frame, and making any one (or three) specific projections is dicey.  We're running a one-time experiment that has never happened in the past 100 million years... if ever.  There is no solid way to predict exactly what will happen when.  We know that bad things are going to start to happen now, but even then, no one will be able to connect the dots and unequivocally say "this is due to climate change."

    But things will get progressively worse.  The day will come in ten, twenty, or thirty years (maybe more, but I don't think so) when so many different things are happening and changing that the costs will be horrendous.

    With that said, whenever that day comes... there will still be more warming in the pipeline.  Climate change takes time, even though we have accelerated the process by a factor of 100.  So when the day comes that (if you could pick the right variables) you win your bet, it will already be way, way too late to do anything about it.  The genie will be out of the bottle. And things will continue to get worse from there.

    My favorite analogy for his is the man who jumped off of the roof of a skyscraper, and whenever he passed an open window, he was heard to say "So far, so good."

    But, to return to your question: no, I don't think so. There is no one particular parcel of evidence that you can reliably pick now, especially in a time frame as short as 20 years.

  25. Making Sense of Sensitivity … and Keeping It in Perspective

    Neal - I think your hunting analogy would get your point across to readers quite nicely.

  26. It's not bad

    In other words, KenD, you don't have to wait for 2033.  You can win that bet right now.

  27. It's not bad

    Sure, KenD.  

    1. Arctic sea ice will be effectively (<250k km2 area) gone in ten years at summer minimum.  According to Funder et al. (2011), Arctic sea ice extent hasn't been lower than current in about 8000 years.  The trend is currently greater-than-linear, and the linear trend has it effectively disappearing at summer minimum within eight years, about 70 years ahead of IPCC AR4 projections.  Even if we remain stable at 400ppm, sea ice is going to continue to decline thanks to the oceans continuing to move toward their equilibrium climate response to the stabilized forcing.

    2. Antarctic and Greenland land ice loss will continue over the next decade at least at the current rate found in Shepherd et al. (2013).

    3. Within fifty years, the process of ecological deconstruction or dis-integration will be obvious.  Species that can move rapidly will leave their niches and attempt to establish equilibria within environments.more suitable to their current configurations.  That may leave some slower and more interdependent species in the lurch.  Species may also respond genetically.  Then there are species that are up against the wall.  A wide range of studies, if academia is alive and well, should be reporting this type of significant change in the biosphere (already occurring, actually). 

  28. Making Sense of Sensitivity … and Keeping It in Perspective

    William Haas:

    I spent some time with Miskolczi to try to clarify his argument. I had to stop it after awhile due to the press of other matters, but in principle the discussion is still open, so I don't want to say too much. However, it is fair to say that his approach is rather non-standard.

    A discussion group of supporters of his formed to try to rewrite his argument in a more transparent way, but after several months they became discouraged and dissolved.

  29. Making Sense of Sensitivity … and Keeping It in Perspective

    William Haas, background on how the Miskolczi mythology arose is at The Climate Denier List.  Scroll to the bottom of that page for links to even more debunkings, and go to the Real Climate Wiki for yet more.

  30. Making Sense of Sensitivity … and Keeping It in Perspective

    elsa:

    There are certainly equations and calculations relating the radiative forcings and the concentrations of the greenhouse gases. They are a bit complex, because the impacts of the different gases depend on the distributions of the gases throughout the atmosphere, and even at a given frequency they do not add linearly. Nonetheless, there is nothing mysterious about them.

    Your concern about the scantiness of CO2 is ill-placed, for two reasons:

    - The bulk of the atmospheric molecules do not absorb in the infrared (IR). Therefore, it does not matter how many there are of them. It is only the greenhouse gases (primarily H2O and CO2) that interact with the IR, so the question boils down to, Are there enough H2O and CO2 molecules to catch the IR photons? It turns out that there are. What matters is the absolute numbers of H2O and CO2 molecules; their proportion to other molecules in the atmosphere is totally irrelevant.

    - Concerning the proportion of CO2 relative to H2O: Here one could make an argument that H2O swamps CO2, for the IR spectral bands they both absorb. However, H2O does not get above 10 km in altitude, whereas CO2 gets up to 100 km. In the theory of the greenhouse effect, the high-altitude molecules have a much more significant impact on the steady-state radiative balance than the low-altitude molecules, so CO2 dominates H2O for their common IR bands.

  31. Making Sense of Sensitivity … and Keeping It in Perspective

    William Haas, Miskolczi (you misspelled his name) is so wrong that even skeptic Roy Spencer dismisses him.  Barton Paul Levenson provides more technical dissection.  Full blown technical takedown is provided by Science of Doom.

  32. Dikran Marsupial at 05:33 AM on 30 March 2013
    It's not bad

    @KenD 50 years of cooling whilst atmospheric CO2 continues to rise, without evidence of substantial changes in the other forcings would constitute a pretty sound falsification I would have thought.  The good thing is that many climate models are available in the public domain, so at least the models are easily falsifiable by plugging in the observed forcings and seeing if the models can explain the observed climate.

  33. It's not bad

    Having occasionally lurked for some time on SkS, I have a longstanding question for anyone who like to take a crack at it. I'd like to be able to offer to some of my skeptical friends and family an example of how AGW might be falsified. Let's say I'm conversing with a skeptic who (perhaps grudgingly) admits the reality of modest AGW but who considers it nothing to fret over, and certainly nothing to justify government intervention. Is there some precise, quantifiable outcome I can predict will obtain within 20 years from now if C02 remains above 400 ppm (or 450 or 500 or whatever), such that if it doesn't happen, I would have to concede I was mistaken as a "warmist"? Something along the lines of Haldane's famous rabbit in the Cambrian? Something I could place money on and collect in 2033?

    For example, could I say, if C02 remains above 400 ppm, then if by 2033 the global sea level average hasn't risen by at least 6 inches (or whatever) or the surface area of the Maldives has not been reduced by 10% (or whatever) or the Antarctic has not lost more than 5% (or whatever) of its ice volume or some other precise costly catastrophe does not occur before then, then we warmists were all mistaken?

  34. michael sweet at 05:09 AM on 30 March 2013
    Earth Encounters Giant Speed Bump on the Road to Higher Sea Level

    I expect WUWT will run a correction for their claims that the pothole two years ago was an indicator that sea level rise was slowing.  Not.

    The rise is steeper that I expected it to be.  Hopefully it will slow down again soon.

    Nice article Rob.  How often do they update the AVISO website with the graph you show?

  35. Making Sense of Sensitivity … and Keeping It in Perspective

    Considering the number of models and the large range of estimated sensitivities, it seems that the estimates are little more than guesses.

    Then there is the work of Ferenc M. Miskokze who has performed analysis that claims that any effect that adding CO2 to the atmosphere would have on climate is compensated for by negative feedback of H20 in the upper atmosphere.

    H2O is modeled as a positive feedback to added CO2 in the lower atmosphere because CO2 warming allows more H20 into the atmosphere which causes even more warming. But in the upper atmosphere the situation is reversed. More CO2 causes the upper atmosphere where LWIR radiates to space to cool. If the earth radiates less in the upper atmosphere then the result will be a net gain in energy by the earth. Cooler upper atmospheric temperatures in the upper atmosphere reduce H2O content. Less H2O contallowsowes more heat to travel up to the upper atmosphere causing temperatures there to rise and the global energy output to space to rise. This negative feedback in the upper atmosphestabilizesizes the climate to changes in green house gasses.

    Moderator Response: [TD] The name is spelled Miskolczi.
  36. Making Sense of Sensitivity … and Keeping It in Perspective

    elsa,

    one of the things the Economist did was doubt climatology,

    False.  The article is close to 3,000 words, all of it citing climate science reports and studies as its foundation.  How can you possibly claim that that means the article doubts climatology?

    What we are not told is the age of the models under investigation.

    False (and off-topic).  There is a wealth of information available on all of the models, and they are continually being improved and expanded.  That no one has sent a personal delivery boy to hand you a gilded copy of the details of the models is no one's fault.  You need to go do some research and educate yourself.

    All it is doing (and the models likewise) is fitting the data to the theory.

    False.  This is off-topic, so I will not bother to discuss it here, but your misunderstanding of the science is pitiful.  Both the models and how CO2 affects temperatures are entirely derived from physics.  You are quoting nonsense that you've read at idiocracies like WUWT.

    You are repeatedly, embarassingly wrong.  Follow the links above, open your mind, and actually read something.  Repeating falsehoods that you read somewhere on the Internet does not make them true.

  37. Making Sense of Sensitivity … and Keeping It in Perspective

    Sphaerica

    I don't think I said that MA Roger agreed with doubting climatology, I think he said that one of the things the Economist did was doubt climatology, which it did.

    With regard to the models you can see from this article that there is a very wide spread of forecasts, which makes them less helpful than they would otherwise be, and the point has now been reached where the actual temperature is hitting the bottom 95% confidence limit.  What we are not told is the age of the models under investigation.

    With regard to the physical process you have not addressed the point.  Yes people have looked at actual temperature and CO2 concentrations but that does not supply an equation linking the two derived from physics.  All it is doing (and the models likewise) is fitting the data to the theory.  Of course such a theory will appear to be true.

    The argument whether CO2 is too small to matter lies at the heart of the debate between us.  I suppose at least you do say IMO!

  38. Earth Encounters Giant Speed Bump on the Road to Higher Sea Level

    The sample size is small, but has anyone looked at whether the effects of ENSO on sea level are amplified as global mean temperature rises?  The idea being the 1997-1998 ENSO event produced a modest dip and rise but the much smaller ENSO over the last few years produced a much larger decrease and increase.  Is the effect of ENSO on sea level nonlinear with temperature?  (I know, I'm asking you to do background research for me, but maybe you just know this from looking at the literature recently.)

  39. doubtingallofit at 03:37 AM on 30 March 2013
    To frack or not to frack?

    Why ignore the science on fracking and go with anecdotes when you don't do that with climate change?  Do any of you know what chemicals go into fracking?  And do you know how many years and how many wells were drilled before any claims of water contamination occurred?  (If you want to protect water, you have to put safety seals on all wells so the owner cannot contaminate the well, regulate all water well drilling, etc.  Should we go there?) I'm not seeing the science here.

  40. Making Sense of Sensitivity … and Keeping It in Perspective

    elsa,

    Quite rightly there is also a questioning of climatology...

    False (and MA Rodger is not supporting that point -- you are misrepresenting his position).

    ...they then use estimates of climate sensitivity derived not from a phsical process...

    False.  And false.

    ...if there is one thing that we all ought now to agree on, those models do not give reliable forecasts.

    False.

    You repeat a lot of myths.  It's time to start supporting your positions.  Most of your comments amount to little more than sloganeering.

    Finally:

    The answer is that the chnages in the composition of the atmosphere have been very small.

    See this.

    Or this.

    Or this.

    The argument that CO2 is too small to matter is possibly the most lame of all positions to take, and demonstrates an ignorance of the science that (IMO) disqualifies a person from participating in any rational, educated discussion.

  41. Making Sense of Sensitivity … and Keeping It in Perspective

    elsa @20 - the only problem with the Economist article is that it's behind the times.  They barely touch on the critical accelerated warming of the deep oceans, and they don't recognize the flaws in the recent low sensitivity studies (which is not surprising, since they're not climate experts).  It's not "denialism", it's just incomplete research leading to flawed interpretations and conclusions.

    I will agree that 'denialism' is all about ignoring evidence.  The difference is that The Econimist isn't just ignoring inconvenient data, they just haven't yet caught up with the current state of climate research.

  42. Making Sense of Sensitivity … and Keeping It in Perspective

    I agree with nealjking that the articles in the Economist (and yes shoyemore I have read both of them all the way through) are not particularly skeptical.  But as various others have noted above there is a hint of what most on here would call denialism.  I doubt that the Economist could change from true warmist to denier in one leap but there is definitely an underlying change of heart in there.  

    Quite rightly there is also a questioning of climatology, as MA Roger has pointed out.  As can be seen from Ed Hawkins' two graphs the current temperature is now outside the 75% confidence limit and touching on the 95% limit.

    (-snip-).  Scaddenp asks me by what physical process I arrive  at a climate sensitivity that is close to zero.  (-snip-).

    Moderator Response: [DB] Off-topic and sloganeering snipped.
  43. Making Sense of Sensitivity … and Keeping It in Perspective

    MA Rodger:

    My interpretation of the article in The Economist is that it is not nearly so skeptical or luke-warmist as you think. In particular, a fair reading of the last paragraph shows that the author is indeed expressing a concern about the actual state of the climate at 4 degrees C, not just the question of how precisely it will be known.

    In other words, the question it addressing is not the academic issue of scientific precision but rather the implications for people living in the world. It is, after all, a newspaper.

  44. CO2 is just a trace gas

    Is the trace gas thing still alive?

    Anyway, for a trace gas, it's amazingly important for life on the planet. Such tiny amounts supply us with food, trees etc.

    Plus, if you just look at the greenhouse gases in the atmosphere (like IR radiation), CO2 is the second most abundant, currently at about 9%.

    Moderator Response: [JH] The comment threads of each and every article posted on SkS are always live.
  45. Making Sense of Sensitivity … and Keeping It in Perspective

    shoymore @15.
    As Dana1981 says, the Economist article is not factually incorrect yet its analysis of those facts is in error. My own take is that the error is so bad, the article is entirely misguided.

    You will note that the context of concluding phrase "Hardly reassuring" that you quote (with to much assurance in my mind). The quote is not saying climate is a problem. It is actually saying climatology isn't up to the job.
    Such is the content of this article from the top 15-year flat temperatures to bottom. The author is continually exhibiting the symptoms of underlying denial.

    As for elsa, consider her/his flip from insisting ECS=0 to suggesting ECS assessments flip about far too wildly 'and you ought to see what I mean' when I tell you that elsa's position no longer fits comfortably alongside itself.

  46. Dikran Marsupial at 20:49 PM on 29 March 2013
    Tung and Zhou circularly blame ~40% of global warming on regional warming

    slasher@14 it is straightforward to show that argument is incorrect.  Let C' be the annual change in atmospheric CO2 (which we can measure directly) and Ea is annual anthropogenic emissions (fossil fuels are taxed, so we have good estimates of that) and En and Un are natural emissions of CO2 into the atmosphere and natural uptake of CO2 from the atmosphere (neither of which we can measure directly).  Fortunately, the carbon cycle obeys conservation of mass, so we know that

    C' = Ea + En - Un

    Technically there should also be a Ua representing anthropogenic uptake (i.e. carbon sequestration), but that is essentially negligible, so it has been neglected.  We can rearrange this to give

    En - Un = C' - Ea

    which means we can estimate the net natural carbon flux from things we can actually measure.  If we plug in the measurements, we get this:

    The green line is the natural contribution to atmospheric CO2, and we can see that it is not only negative (meaning the natural environment takes up more carbon from the atmosphere than it emits into it), but that it has been taking more and more carbon out of the atmosphere each year as time progresses. So if it were not for fossil fuel emissions, CO2 levels would currently be falling, rather than rising.

    According to the IPCC reports, the carbon cycle has actually intensified, with the natural fluxes both into the atmosphere and out of it increasing.  See below, the figures in red show the changes in the fluxes since the pre-industrial equilibrium. This shouldn't be too much of a surprise, if only because moving a substantial amount of carbon from the lithosphere into the atmosphere (via burning fossil fuels) means that there is more carbon sloshing about.  See the IPCC report for details, or better still, David Archers excellent primer on the carbon cycle.

    I suspect any further discussion of this topic should be on a more appropriate thread, such as this one
  47. Making Sense of Sensitivity … and Keeping It in Perspective

    Elsa,

    "To claim that we know with 95% confidence (which actually the IPCC has never done) that the average temperature will rise by x degrees cannot sit comfortably alongside this statement."

    I think everyone here would agree. So where does this 'claim' come from? Pulled off a less than honest/accurate blogsite?


    There's no need to emphasise uncertainy where everyone here is aware of it. If we knew to a preciser degree what conditions would be like 30, 60 and 100 years from now, policy prescriptions would be easier to formulate. The perennial counter-argument of the 'skeptical' - that we have no certainty on the matter - somehow never seems to make it felt on them that this is cause for greater concern than better knowledge. Surely uncertainy means we should say, "it could be better or worse than our middle estimates," and therefore consider the full spectrum of risk. But when 'skeptics' say, "it's uncertain," they mean for us to hear, "it's going to be much less of a problem than we need to worry about." That's the rational disjoint in their whole thesis. Even skeptic Roger Pielke Senior advances this quite resonable proposition.

     

    "I don't think we know the consequences of what we're doing. But our footprint on the environment is more than just CO2: It's nitrogen deposition, it's the other black carbon, the aerosols, it's land-use change. And so we put all of these things together and say, "How can we come up with a policy that reduces our impact on the environment?" Because we don't know the consequences....

    The problem is, we don't know if we're pushing ourselves toward or away from some negative impact. That's the problem. We could be making ourselves actually less likely to have some drought pattern, but since we don't know, to me the prudent pattern is to try to minimize our impact."

    http://www.motherjones.com/environment/2008/10/qa-roger-pielke-sr

    Knowing less than Pielke and less than many here, I reflect that human industry has added 40% more CO2 to the atmosphere in a couple of centuries - an astonishing amount - and the surface temperature of the earth has definitely increased in that time. More uncertainty about causes and the future makes me feel more, not less concerned. The 'skeptics' have a much more rosy view of the future, but no good reason for it without being highly selective in their reading. The 'skeptical' blogs are their filter.

     

  48. Making Sense of Sensitivity … and Keeping It in Perspective
    (snip)
    Moderator Response: [Albatross] Off topic content deleted.
  49. Dumb Scientist at 13:00 PM on 29 March 2013
    Tung and Zhou circularly blame ~40% of global warming on regional warming

    Atmospheric CO2 increased faster after 1950.

  50. Tung and Zhou circularly blame ~40% of global warming on regional warming

    significant deforrestation has not been replaced with other plants, significant deforrestation are in urban areas, the deforrestation reduces the co2 cycled through natural systems leading to more atmospheric co2

Prev  929  930  931  932  933  934  935  936  937  938  939  940  941  942  943  944  Next


The Consensus Project Website

THE ESCALATOR

(free to republish)


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