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  1723  1724  1725  1726  1727  1728  1729  1730  1731  1732  1733  1734  1735  1736  1737  1738  Next

Comments 86501 to 86550:

  1. A Flanner in the Works for Snow and Ice
    Ken Lambert @153: 1) Why be charitable? You have already taken the opportunity of my mother's ill health and my being preoccupied with helping family members shift house to declare victory. Why should this time be any different? 2) It is not your attention to the "errors of others" which makes your character questionable - it is your inability to acknowledge any error you yourself make. 3) Apposite of which, your "assumptions" have been irrelevant to every error of yours I have pointed to. That is because I calculated a particular value, ie, the net incoming energy absorbed by the arctic the summer season of 2010 - the net incoming energy absorbed by the arctic in the summer season of 1979. I know when I calculate that value and get a figure in Watts per square meter, and then I multiply by the area by 60 by 60 by 24 by 90 that I have calculated a value for a 90 day period. Your assuming that the value is actually that of a thirty day period is therefore just an error. It is, what's more an error that you repeated several times after correction, and have never admitted to. It is not an error of calculation simply because you do not bother doing the sums. In like manner, when I actually look up the monthly data for sea ice area for the respective periods, and determine the difference in sea ice area between 1979 and 2010, your assumption that the actual loss of area over that thirty year period is just the loss of sea ice calculated by Trenberth for a single year is again simply an error. It is just as much an error as if you used the diameter of the moon to calculate the surface area of the Earth, and no matter how exact your equations are, the error in the initial values means your equations are useless. 4) With regard to the decimal places, sometimes it is just easier to cut and paste. The number of decimals means nothing more, nor less than that. Typically, you however try to make so simple a matter the basis of an ad hominen. 5) Finally, your argument style of making a false statement, ignoring the correction, making it again, and ignoring the correction, and making it again, and so on until you hold the field by exhaustion of the opposition shows an absolute lack of intellectual integrity. It reminds me of nothing so much as the debating style of some creationists I have known.
  2. Berényi Péter at 00:38 AM on 6 May 2011
    Arctic Ice March 2011
    Response: [DB] The reality is that spring 2011 conditions as measured by PIPS 2.0 are worse than those of spring 2010
     The reality is that the proposition above is not true if by "worse" you mean extension of thick ice is smaller in the central arctic this spring than it was a year ago. Of course if you mean something else, it can be made true. Clarify your position please.
    Response:

    [DB] See Riccardo's point below about cherry-picking.

  3. Lindzen Illusion #4: Climate Sensitivity
    David, Chris, Lindzen's explanation for the ice age climate changes is that they were forced by changes in the distribution of solar forcing (orbital changes) to which he believes the climate system is much more sensitive that it is to changes in mean solar forcing (or mean CO2 forcing). Here's a representative piece (including a reply by Hoffert and Covey): http://eaps.mit.edu/faculty/lindzen/165pal~1.pdf That note (from 1993) has no actual calculations in it, and in this day and age it ought to have been trivial for someone to have built a simplified GCM with low climate sensitivity, and to see whether it is capable of producing an ice age. That no one has done so suggests that it's not possible to come up with a consistent model that reproduces the earth's observed behavior, and has climate sensitivity as low as Lindzen proposes.
  4. Lindzen Illusion #4: Climate Sensitivity
    "In the current models, for reasons that puzzle almost everyone, the cloud feedbacks are positive rather than negative." This is a gem. Yes, back in 1989, it was a puzzlement. Yet, most recently, measurements have born out the results of whatever early models Lindzen was referring to. I'm referring to the post on this site, "What is the net feedback from clouds?", and in particular Dessler (2010), "A Determination of the Cloud Feedback from Climate Variations over the Past Decade". Lindzen's concern was valid in 1989, but it no longer carries the weight it once did. David H, indeed, the disagreement between the paleologic record and Lindzen's model has been raised before, but likewise, I haven't heard of a Lindzen explanation.
  5. Dikran Marsupial at 00:16 AM on 6 May 2011
    Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
    BP@68 I meant that terra preta rapidly looses its fertility if you carry on using it without maintenance. However, thanks for the reference (although your manner left a bit to be desired), it is both interesting and surprising that carbon in that form should be so long lasting.
  6. Ken Lambert at 00:03 AM on 6 May 2011
    Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
    Marcus #28 Marcus, I will be the first to buy your PV Solar panel when it can re-produce itself without the help of relatively cheap fossil fuels. { - snip - } their democratically elected governments back to 1900 who started the electricity generation industries with (except for hydro), the only feasible, abundant and cheap fuel available - fossil fuel - chiefly coal.
    Moderator Response: [muoncounter] Accusations of ignorance and conspiracy theories are deleted. You know better than that.
  7. Berényi Péter at 00:02 AM on 6 May 2011
    Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
    #66 Dikran Marsupial at 23:08 PM on 5 May, 2011 terra preta is rapidly degraded and you have to maintain it or it doesn't stay fertile It explains why hundreds of thousand square kilometers of the Amazon basin are still covered by (yes, fertile) terra preta after the natives, decimated by European plagues, abandoned it five hundred years ago. Or does it? Soil Biology & Biochemistry Volume 41, Issue 2, February 2009, Pages 210-219 doi:10.1016/j.soilbio.2008.10.016 Black carbon decomposition and incorporation into soil microbial biomass estimated by 14C labeling Yakov Kuzyakov, Irina Subbotina, Haiqing Chen, Irina Bogomolova & Xingliang Xu "Considering about 10 times slower decomposition of BC under natural conditions, the mean residence time (MRT) of BC is about 2000 years, and the half-life is about 1400 years. Considering the short duration of the incubation and the typical decreasing decomposition rates with time, we conclude that the MRT of BC in soils is in the range of millennia".
  8. Brisbane book launch of 'Climate Change Denial'
    Wow, the big guns were brought out for that one. Mixing with the celebs.
  9. Ken Lambert at 23:47 PM on 5 May 2011
    A Flanner in the Works for Snow and Ice
    Tom Curtis #148 "However, in light of Lambert's unsavoury characteristic of claiming victory anytime a response delayed, in light of his incapability of admitting error coupled with a determination to score rhetorical points of the errors of others, and in light of his inability to keep even simple concepts straight (as for example the difference between change in incoming energy due to change in albedo (as discussed here) as distinct from the amount of energy used to melt a particular volume of ice (which he repeatedly treats as equivalent), no response will be forthcoming. I find arguments from obtuseness uninteresting - and evidently, that is all that Lambert has to offer this forum." In a spirit of goodwill Tom, I will restrain myself from suggesting that you have thrown in the towel. Would you prefer that I ignore the 'the errors of others' while being pilloried with terms such as 'ridiculous' and 'fool' when producing sound calculations based on the information from Dr Trenberth - a leading scientist in this field? I would be failing in a duty to myself and the readers of this site if I allowed gross errors to go unremarked which are intended to disprove and damage my arguments. Several time you have discovered errors and re-calculated -- only after I pointed them out. You even produced bizarre gems like this: "More usefully, the average annual temperature anomaly between the 80's and the 2000's for the area from 67 degrees north to the pole is 1.2832875654 degrees C." Was that a joke I missed or were you trying to impress the gullible by quoting a temperature to 10 decimal places? You have admitted that none of my calculations were wrong. You have disputed my assumptions, and I have disputed yours. Mine produced results close to the NET heat absorption calculated by Dr Trenberth - yours don't. Let that be the end of this fraught but necessary encounter.
  10. Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
    TTTM @62, my plan is curtail CO2 emissions before wide spread sequestration becomes necessary. It's cheaper that way. In the event that sequestration becomes necessary I will defer to the experts, of which I am not one. I am, however, knowledgeable enough to recognise a claim that sequestration technologies are unproven to be nonsense. Some are, certainly, but your argument requires that all are uproven, which is simply false.
  11. Berényi Péter at 23:33 PM on 5 May 2011
    Arctic Ice March 2011
    #238 Don9000 at 22:35 PM on 5 May, 2011 The Arctic seems poised on the brink of another record melting season.
     Not likely. A much larger area is covered by thick ice in the central arctic ocean now than in 2007.
    Response:

    [DB] Why the cherry-pick of 2007 - a record melt year due to weather conditions (strong Arctic Dipole)?  The Central Arctic Basin has not had MY ice coverage in years; all ice there now is typically first year ice, most of which does not survive the melt season regardless of thickness.

    The reality is that spring 2011 conditions as measured by PIPS 2.0 are worse than those of spring 2010, a year of continuing ice loss without evident recovery and itself part of an ongoing trend towards zero and oblivion (cue: Fade to Black):

    April trend

    But thanks for providing readers with yet another measurement tool which they can play with: PIPS 2.0

     


    Courtesy Neven's Arctic Sea Ice blog:

     

    NSIDC has just released its April analysis. Some interesting tidbits:

    Arctic sea ice declined slowly through most of April. Because of the slow decline in April, ice extent for the month as a whole did not approach record lows, as it did in March. However, ice extent began to decline more quickly towards the end of the month.

    Central Russia saw an early retreat of snow cover, as a result of prevailing warm conditions during the past winter over the eastern Arctic and Siberia.

    (...)

    Ice extent declined through the month more slowly than usual, at an average rate of 29,950 square kilometers per day (11,560 square miles per day). The average daily rate of decline for 1979 to 2000 was 40,430 square kilometers (15,610 square miles) per day.

    Cool conditions helped retain ice in Baffin Bay, between Canada and Greenland. Most of the ice loss during April was in the Kara Sea, north of Siberia, and the northern Baltic Sea in Europe. Ice also retreated rapidly in the western Bering Sea and the Sea of Okhotsk.

    (...)

    For most of April, nearly all of the eastern Arctic, north of Europe and Russia, remained warmer than average. The largest anomalies were over central Russia, northern Siberia and the Laptev and East Siberian Seas, where temperatures averaged over the month were approximately 6 degrees Celsius (11 degrees Fahrenheit) above average. In contrast, most of the western Arctic was cooler than normal, with temperatures 6 degrees Celsius (11 degrees Fahrenheit) cooler than average over Davis Strait and Baffin Bay.

    The eastern Arctic remained warmer than average all winter. This suggests that that sea ice there did not thicken as much as in past winters, and may retreat rapidly as the summer melt season progresses.

    (Emphasis added)

  12. Dikran Marsupial at 23:08 PM on 5 May 2011
    Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
    BP@65 Can you give a reference for carbon (in the form of charcoal) having a long half life in soil. I ask as your terra preta example seems to suggest otherwise (terra preta is rapidly degraded and you have to maintain it or it doesn't stay fertile). It seems more likely that increasing the carbon content of the soil will just increase soil respiration (i.e. those abundent bacteria).
  13. Bob Lacatena at 23:04 PM on 5 May 2011
    Arctic Ice March 2011
    238, Don9000, Interesting, but I wouldn't get too carried away with either the descent of the curve, or any particular measure of melt "performance." On the descent of the curve... sudden changes in winds and currents, clouds, temperatures/stalled air masses, etc. all lead to abrupt and unexpected reversals (in either direction). At the same time, for example, any 15% ice graph is a limited, scalar representation of a complex system. It's is breaking down a hugely complex dynamic to a single "representative" number. IJIS offers a different estimate and a more informative graph. My own opinion is that the COI number (30% or more instead of 15%) is a better method for most purposes, and the ice area instead of extent at Arctic ROOS is useful information. But none of these shows ice volume (i.e. area * depth) or the nature of the ice itself, so they all have limits. Lastly, looking at the actual geographic distributions in concentration at Cryosphere Today is hugely important to see what's happening. The animations give a sense of "flow" and hint at what might happen next, or what's happening now that's different from the past. Their archives and date-to-date comparison pages are great tools, too. For example, I don't know how often the huge drop in concentration that we now see at the pole itself has happened in the past. This year to date has been looking very scary, not necessarily because any measure of melt looks fast, but rather because all around this year looks different, and different can lead to fast or maybe scary fast. Then of course, later in the year it's fun to actual see things with your own eyes, using the North Pole Cams to see the melt pools develop, along with an occasional rainbow.
  14. Daniel Bailey at 22:44 PM on 5 May 2011
    Arctic Ice March 2011
    Thanks, Don. The mild Arctic winter has preconditioned the sea ice cap there for a near-record to possibly a record melt season. It will be interesting to watch unfold, like a train wreck. Or a Curry post. The Yooper
  15. Berényi Péter at 22:43 PM on 5 May 2011
    Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
    #62 TimTheToolMan at 20:59 PM on 5 May, 2011 Ploughing charcoal into fields isn't sequestering it. It is. Carbon content of charcoal has an extremely long halflife in soil. But it is not a big deal in itself. Carbon sequestration for its own sake is plain silly and prohibitively expensive like turning plantation timber into charcoal then burying it in abandoned mines. However, adding charcoal to tropical oxisols makes perfectly good sense. With the help of some bacteria abundant there it turns them into extremely fertile terra preta. Even if you can't "save the Planet" this way (I don't think it needs saving), you can certainly save people (from poverty & famine). The method does not work so well for soils found in temperate regions, although it may depend on finding the right kind of bacteria that would serve as an interface between plant roots and nutrients adsorbed on the (huge) surface of charcoal particles in that environment. Also, you do not need timber to produce charcoal powder. Just about any agricultural waste suffices if it is burnt in a low oxygen environment. If it is done properly, you can even extract some energy during the process, because hydrogen contents of organics have to be oxidized anyway (to water) and the carbon monoxide should be trapped and burnt fully (unlike CO2 it's a poison).
  16. muoncounter at 22:39 PM on 5 May 2011
    Arctic Ice March 2011
    Don9000#238: But it's back within the two sd gray bars, so it must all be a natural cycle. For now.
  17. muoncounter at 22:37 PM on 5 May 2011
    Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
    TTTM#40: "Nobody likes being told what they can and cant do." True enough. But many learn in childhood that's the way of the world. We drive on the correct side of the road, stop at red lights and don't get to throw our waste products out into the street. Oh, sorry, exception for the last one of those: we've been throwing our fossil fuel waste into the collective street for years.
  18. Arctic Ice March 2011
    The Arctic seems poised on the brink of another record melting season. The May 4 update on the National Snow and Ice Data Center website explains that after a slow April melt, the melting trend has recently accelerated, and the trend line, as seen in the daily image update, is poised to drop well below the 2006 record. National Snow and Ice Data Center website
  19. Pete Dunkelberg at 22:34 PM on 5 May 2011
    Why 450 ppm is not a safe target
    # 22 Jesús Rosino - more than + 1 meter not supported by a physical model? Are you thinking of a linear model?
  20. Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
    Wow Tim, you really have *no clue* about the carbon sequestration potential of soil biomass, if you don't think that putting organic carbon into the ground isn't sequestering it. The initial point of bio-sequestration, though, is to significantly *reduce* the trajectory at which CO2 emissions are rising-& both bio-char & algal biomass represent a relatively cheap & easy way to do that-certainly much cheaper & easier than building dams & massive pipelines, or moving tens of millions of people to higher ground. It is also much cheaper & more effective than liquefying CO2 & burying it under ground. The reality is that pilot projects have shown that algal biomass can absorb between 55% to 80% of the CO2 released by a 1000MW coal power station. As I said above, once you've tied up that CO2 in biomass, you can use it to make petroleum substitutes (thus displacing the CO2 emissions produced by burning petroleum products directly), you can use it as a fertilizer or high protein feed (again, displacing the emissions that would normally be generated from manufacturing these products), you can use it to make bio-plastics (again, displacing the CO2 emissions that would be generated if you made those plastics directly from fossil fuels), you can also gasify it & burn it for heat & electricity (again, displacing the CO2 that would normally be generated if you mined the coal or natural gas & used that for electricity). Heck, you can shove some of it down into a empty mine-shaft for all I care. The point is that you're effectively *re-using* the CO2 emissions generated from the burning of fossil fuels, thus significantly reducing the rate at which CO2 levels in the atmosphere continue to rise. Now, if you couple that with greater energy efficiency (Demand Management), greater use of non-carbon based energy sources, greater use of bio-gas for base-load energy(from landfill, sewerage plants, forestry sites & farm residues) & reforestation, you could get the trajectory of CO2 emissions to flatten out completely, even *fall* slightly. It can be done, & at a fraction of the total cost of your extremely lame, & hideously expensive "adaptation" approach.
  21. Why 450 ppm is not a safe target
    #23, newscrusader "Now the AMAP assessment finds that Greenland was losing ice in the 2004-2009 period four times faster than in 1995-2000." There are conflicting data on the rate of Greenland ice loss, and if the ice sheet was closer to balance in 1990-95, a fourfold increase does not have to be very significant towards very rapid meltdown. Four times very small is still very small. It is only when we have reached a much higher rate of ice loss than today, and it keeps on multiplying, that we can start talking about a rapid meltdown. And we are definitely not there yet. But I can't see how anyone can be so sure we won't get there, in some not too distant future.
    Response:

    [DB] As an FYI, the dangers to changes in SLR from Green Ice Sheet mass loss lie less in surface melt, which is still considerable, than they are due to increases in calving and ice stream transport in marine terminating glaciers like Jacobshavn, Petermann and Zacharaie. 

    The latter, Zacharaie, is the one with the most potential to change from its current transport and calving dynamic into a different dynamic/phase state of greatly increased transport and calving.

  22. Pete Dunkelberg at 22:15 PM on 5 May 2011
    Why 450 ppm is not a safe target
    How safe is 450 ppm CO2? Think of sea level. How high was it the last time CO2 went above 440? How high can the sea rise by 2100? Given that the great, massive ice sheets will slip into the sea faster as they warm, and that the process can hardly be expected to be merely linear, + 5 meters can not be ruled out even if it is the high end of predictions. Anything over + 1.5 meters is a very large problem. How quickly can you move a large city? Where would you put a whole bunch of them in a hurry? Policy implications: first note that we are on course to far exceed 450 ppm by 2100, and time does not stop then. To sanely set policy, one must first bound the risk, or in other words determine a worst case scenario. Then set policy to allow virtually no chance for that case. Conclusion: stop burning carbon. We have other energy sources, we only lack a decision to use them.
    Moderator Response: [DB] 1.5 meters is a fraction of Miami, but about 90% of its high-end real estate.
  23. Climate Change Denial book now available!
    "Climate change can be solved – but only when we cease to deny that it exists. This book shows how we can break through denial, accept reality, and thus solve the climate crisis." Really? Is that what the science says? I think this website is fantastic, and I appreciate all the work that you do to debunk the deniers. But that assessment seems fatuous. The climate change already in the pipeline is nothing short of catastrophic for humans and most other species. To say we should "accept reality" and "thus solve the climate crisis" is surely a contradiction in terms. Or maybe just marketing.
  24. TimTheToolMan at 20:59 PM on 5 May 2011
    Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
    So if I have this right Tom would tie up vast tracts of land for the purposes of growing trees to be buried in mines. Is that really your plan? Where would we do this, Tom? Ploughing charcoal into fields isn't sequestering it. And why are you now worrying about a runaway greenhouse effect? Surely if the earth could runaway then it would already have done so when we had thousands of ppm and no permanent icecaps in the past.
    Moderator Response: (DB) Read up on the faint young sun hypothesis for a correction to your last statement.
  25. Brisbane book launch of 'Climate Change Denial'
    Congratulations John!
  26. Arkadiusz Semczyszak at 20:31 PM on 5 May 2011
    Lindzen Illusion #4: Climate Sensitivity
    It is worth noting that with Lindzen does not agree well, and some skeptics - as noted Sk.S. and behind them other blogs Well, the climate sensitivity is a problem " in itself". Uncertainties are large - Another look at climate sensitivity, Zaliapin and Ghil, 2010: “... for example in response to large increases in greenhouse gases or to other major changes in the forcing, whether natural or anthropogenic. This latter problem requires global interdisciplinary efforts and, in particular, the analysis of the entire hierarchy of climate models (Schneider and Dickinson, 1974), from conceptual to intermediate to fully coupled GCMs (Ghil and Robertson, 2000). It also requires a much more careful study of random effects than has been done heretofore (Ghil et al., 2008). It seems to us that Roe and Baker’s title question “Why Is Climate Sensitivity So Unpredictable?” still remains open. (This paper is a reference to: Hannart, Dufresne and Naveau: Why climate sensitivity may not be so unpredictable, 2009.) Could also add the problems with: the probability ... and one more note about clouds - do not forget about paper: Is There a Missing Low Cloud Feedback in Current Climate Models? Stephens, 2010.: “The consequence is that this bias artificially suppresses the low cloud optical depth feedback in models by almost a factor of four and thus its potential role as a negative feedback. This bias explains why the optical depth feedback is practically negligible in most global models (e.g., Colman et al., 2003) and why it has received scant attention in low cloud feedback discussion.”, because: “An analysis by Prof. Graeme Stephens in the article on page 5 suggests that solar radiation reflected by low clouds is significantly enhanced in models compared to real cloud observations. This finding has major implications for the cloud-climate feedback problem in models.” However, for most skeptics are not out of the clouds - the climate sensitivity on the doubling of CO2 - are the main problem, and GPP: Terrestrial Gross Carbon Dioxide Uptake: Global Distribution and Covariation with Climate, Beer et al. 2010.: “Most likely, the association of GPP and climate in process-oriented models can be improved by including negative feedback mechanisms (eg, adaptation) that might stabilize the systems.” Let me remind - here - the papers: The ecological role of climate extremes: current understanding and future prospects, Smith, 2011. i Effect of soil moisture and CO2 feedbacks on terrestrial NPP estimates - about a possible revaluation - here - certain positive feedback - in the IPCC models. That is why in the latest computer models - the summarizing RF for doubling of CO2 - less than 2 degrees K. 'Greener' Climate Prediction Shows Plants Slow Warming, Lynch - NASA, 2010. And even allowing that: “The range of feedback coefficient is determined by climate system memory. The longer the memory, the stronger the positive feedback. The estimated time constant of the climate is large (70 ~120 years) mainly owing to the deep ocean heat transport, implying that the system may be not in an equilibrium state under the external forcing during the industrial era.”
  27. funglestrumpet at 20:27 PM on 5 May 2011
    Brisbane book launch of 'Climate Change Denial'
    Congratulations! I am reminded of two quotes: 'A journey of a 1000 miles begins with a single step' (Lau Tzu) and 'If you are not on the road to Utopia, you are not on the right road.' (Unknown) I am sure that you are headed towards Utopia, I only hope that for the sake of all of us you get at least half-way there.
  28. Brisbane book launch of 'Climate Change Denial'
    Congratulations, good show! But you need to work a bit on your stance for photos: Arms behind your back? No way.
  29. Lindzen Illusion #2: Lindzen vs. Hansen - the Sleek Veneer of the 1980s
    A model is something which take a inputs "scenario" and get the outputs. You can model say a cannonball, and construct scenarios for elevations of 10,30, and 45 degrees. However, if you actually experiment with an elevation of 30 degrees, why would you be interested in comparison with the 10 and 45 predictions? Comparing with Scenario C is like noting that your 10 degree elevation prediction matched it better because your model overestimated the powder. Simple is useful for education, not real world. By that logic you should love Wally Broecker's pretty spot on prediction of 2010 temperature that he made in the 1970's. However the model used, while actually an amazing thing, makes Hansen's model look seriously sophisticated. A wet sphere (no ocean) dry part on 2/3 of upper hemisphere from memory. Wally overestimated the CO2 (thought we would be at 400) while the model only had a sensitivity of 2.3 from memory. (I'm away from papers). You want real airplanes to be designed from a high school flight model, because it's simple? No. Hansen did what he could within the limitations of the day. You want as much real world physics in there as possible for a good prediction.
  30. Brisbane book launch of 'Climate Change Denial'
    Congratulations.
  31. newcrusader at 19:08 PM on 5 May 2011
    Why 450 ppm is not a safe target
    From the AP article: (From a Post at CP) Now the AMAP assessment finds that Greenland was losing ice in the 2004-2009 period four times faster than in 1995-2000. That’s a doubling time of about five years, a continuation of which terminates the ice sheet by about the 2060s. This is exactly what Hansen was worried about in his recent paper. It’s true that there’s no paleo-analog for such a rapid collapse, but similarly there’s no paleo-analog for the unnatural forcing we’re applying. The West Antarctic Ice Sheet would disappear at least as quickly, and if both go that’s about 13 meters sea level rise. Continued thermal expansion, a relatively modest contribution from the East Antarctic Ice Sheet and minor sources would likely push things into the 20 meter range.
  32. Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
    TTTM believes that sequestering carbon is an unproven technology. However, the simplest method of sequestering carbon is to turn plantation timber into charcoal. The technology to to that was in wide spread use several thousand years ago. The charcoal can be buried in abandoned mines (if ploughing it into fields is considered unwise. Other technologies are available if less proven. In fact, so long as we actually achieve zero emissions, the increase in CO2 levels will reduce to a quarter of its highest value just as a result of the natural "sequestration" in the ocean abyss. That process will take one to two centuries, so waiting for it my be a bit reckless. However, given sufficient time, this process will reduce 560 ppm to 350 ppm, ignoring the risk of triggering a runaway effect. (It takes around ten thousand years for the remainder of the CO2 to be eliminated by natural means.) The key point is, the sooner we stop emitting Carbon, the more time we will have to evaluate the risk of our then current CO2 levels in the atmosphere, and to take extra steps to reduce it if necessary. The alternative of following a path of adaption only is an experiment in seeing how well humans can survive in the face of massive ecosystem collapse and (if continued long enough) anoxic oceans.
  33. kampmannpeine at 18:43 PM on 5 May 2011
    Brisbane book launch of 'Climate Change Denial'
    Congratulations John, if you need somebody to help translating the book into German, give me a shout ... Jörg
  34. CO2 is plant food? If only it were so simple
    Apologies for the poor formatting above - copying & pasting from a pdf is fraught with danger!
  35. CO2 is plant food? If only it were so simple
    "I worked 10 years (including: for the Department of Agriculture - the U.S.) on the influence of climate on aphids - and their "enemies” (10 years I taught the students of agriculture, what you should know about: pest control - climate). The most interesting - to my - "paradox" here was that after every cold winter - usually - there were more aphids (unlike the “warm” winter). "Enemies" of aphids, they are simply being reduced more strongly - by frost - during the cold winters - more strongly than aphids." Interesting that you neglect to note the fact that warm winter temperatures are also beneficial to aphid phenology (see e.g. Zhou et al (1995) Global Change Biology; Bale et al (2002) ibid; Harrington et al (2007) ibid). From the first of those references: "...A 1 °C increase in average winter temperature advanced the migration phenology by 4–19 days depending on species...". From the second: "...even with global warming the threshold temperatures for ¯ight are rarely exceeded and apterous aphids are more fecund than alatae. Anholocyclic aphids, unlike the overwintering eggs of holocyclic species, do not have a winter diapausing stage and are not required to pass through one or more wingless generations on the winter host prior to host alternation. The former can therefore colonize crops more quickly when spring conditions become favourable..." From the third: "...The extent to which any changes in aphid phenology will translate into changes in the pest status of aphids will depend partly on how the phenologies of their crop hosts change. In the case of annual spring planted crops, planting dates depend greatly on soil condition in spring, and this is affected particularly by winter and spring rainfall, less so by temperature. With aphids, it is probably the other way around. There is much more uncertainty over future patterns of rainfall than there is over temperature, and it is hence difficult to predict how crop phenology will change. In the case of potatoes and sugar beet in the United Kingdom, unpublished data suggest that planting dates are not advancing as fast as aphid first flight dates. If this is the case, aphids may arrive when crops are at an earlier and more susceptible growth stage..." Takehome message - Arkadiusz should know this research if he has worked on aphids for as long as he claims. The final sentence of the final paper I reference is the clincher - "aphids may arrive when crops are at an earlier and more susceptible growth stage". As Arkadiusz should know there is a lag between aphid arrival in crops and their detection by predators it is this period that is most important to the effect of aphid pests on the crops, as virus transmission and feeding damage will occur then. It is known that if aphids are particularly abundant in the early season then they are less so later on in the year (due to predator action - and the opposite is also true, if aphids are less common in the early season predators are less successful and there is a flush of late aphids at the end of the season) but it is in the early stages of crop development that virus transmission and feeding damage are most important.
  36. Jesús Rosino at 17:41 PM on 5 May 2011
    Why 450 ppm is not a safe target
    When Hansen and Sato 2011 get trough peer review (which I think it won't), I'll take it seriously. 5 m. sea level rise caused by 450-ppm CO2 concentration is far from being not only consensus but taken seriously by thier colleagues. I don't even think that "more than 1 m." can be regarded as consensus, given that it's not suppoted by physical models.
  37. TimTheToolMan at 17:15 PM on 5 May 2011
    Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
    "Why not? As long as the carbon is taken out of the air and kept out of it." Because "high protein feed & fertiliser" doesn't keep it out of the air. It returns quickly. Same for plastics albeit over a longer period. A tree that dies and rots returns its carbon back too... Compare these to oil and coal stored deep underground for millions of years. Now thats sequestering. The carbon is removed from the carbon cycle. Growing stuff is simply having a larger portion temporarily out of the atmosphere but still in the Carbon cycle. It helps but its not sequestering.
  38. Philippe Chantreau at 17:08 PM on 5 May 2011
    Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
    "Thats not sequestering is it" Why not? As long as the carbon is taken out of the air and kept out of it. Any solid using atmospheric carbon as building blocks is a mean of sequestering. What is done with it does not matter the least, provided it is not oxydized in a way returning the carbon to the atmosphere. "And at any rate, there is a WORLD of difference between a trial and reducing global CO2 levels by 40+ ppm." And of course, "skeptics" are working as hard as they can for that difference to never be reduced.
  39. TimTheToolMan at 16:48 PM on 5 May 2011
    Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
    "These micro-organisms are highly useful for the production of bio-plastics, high protein feed & fertilizer." Thats not sequestering is it. "Yet though the technology exists" No it doesn't. The "technology to grow stuff" isn't technology. The sequestering bit is doing something effective with it afterwards to lock the Carbon up. And at any rate, there is a WORLD of difference between a trial and reducing global CO2 levels by 40+ ppm.
  40. Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
    "Sequestering is a whole other ballgame for which we currently have no technology." Shows how little you know, TTTM. There are already a number of highly successful trials where they are able to sequester carbon dioxide in various kinds of biomass (mostly algae & bacteria). These micro-organisms are highly useful for the production of bio-plastics, high protein feed & fertilizer. Yet though the technology exists, its not being adopted because the Deniers still insist that there isn't a problem with CO2 or they still insist that the highly inefficient Geo-Sequestration technique is the way to go.
  41. TimTheToolMan at 16:23 PM on 5 May 2011
    Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
    "TTTM, please work on your reading comprehension. I don't like having to repeat myself." I would prefer it if you didn't attack me like that. Afterall my posts are censored for far less. Somehow I dont think your post has a snowball's chance in hell of being removed. I dont have a problem understanding. Emissions haven't stopped by 2050 under your ideal global scenario. We wont be stabilised at 450ppm we'll still be increasing at 50% the rate in 1990. Thats hardly stabilised is it. Sequestering is a whole other ballgame for which we currently have no technology. I would prefer to invest heavily in fusion rather than sequestering technology.
  42. Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
    "'Nobody likes being told what they can and cant do.' And sadly, noone likes paying for the mess they have created either." TTTM's response is a complete straw-man. By his perverted logic, I could say that no-one should have to pay for destroying someone else's personal property, or pay the price for physical assault, or murder, or rape....you get the picture. Yes, people don't like to be told what to do but, in a civil society, people also recognize that they have certain Rights & Responsibilities. We know we live in a land of laws & that sometimes we're required to make recompense for the the messes we make-except, apparently, in Denial land-where everyone just does as they please without any responsibility, & apparently where magical fairies maintain the infrastructure of their entire society.
  43. Why 450 ppm is not a safe target
    CB Dunkerson quoted & wrote:- "owl905 wrote: "Why have you written an article about 450ppm CO2 when the issue is 450ppm CO2e?" Which... is one of the points made by the article." No it isn't; not in the least. The article is pointing at the 450 mark for CO2 and adding subjective inclusions from the rest of the pollution problem. "As the article notes in the second paragraph, CO2 ppm alone is often used" No it isn't. That's the point of my objection - the 'often used' is CO2e - and that's the correct framework. "... on the grounds that aerosol cooling offsets warming from other greenhouse gases." There's no such grounds, no such basis, and no science claiming a past equilibrium that extrapolates to a 'CO2/450ppm.' The statement appears to be a misinterpretation of the Radiative Forcing historical chart used by the IPCC (AR4-WG1-Ch2, p.136). From the article: "At present we use the concentration of CO2 in the atmosphere as the indicative measure of future temperature." Untrue. CO2e is used literally everywhere. The CO2 focus isn't because of a preeminence in temperature rise, it's because of the long residency in the source/sink cycle.
  44. Lindzen Illusion #2: Lindzen vs. Hansen - the Sleek Veneer of the 1980s
    angusmac - I still don't see your point. Yes, scenario C coincidentally fits observed temperatures pretty well. We know it's coincidental because that scenario in no way matches reality. The forcing is lower and the sensitivity is higher. Those two opposite inaccuracies just happen to cancel eachother out. If we bump our adjusted Scenario B up to a sensitivity of 3.4°C, it would match observations better. But I decided it would make more sense to use the IPCC most likely value (3°C). So it seems like if we boil it down, you're arguing that real-world climate sensitivity is on the high side.
  45. Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
    TTTM, please work on your reading comprehension. I don't like having to repeat myself.
    "Plus rather than blowing past the danger limit with CO2 levels continuing to rise rapidly, we'll have set up the technologies and infrastructure necessary to continue reducing emissions to safe levels."
    450ppm likely isn't immediately disastrous. It's dangerous if we remain at that level for many decades, allowing ice to continue melting. We first need to stabilize at 450ppm before we can work on reducing CO2 below that level.
  46. Lindzen Illusion #2: Lindzen vs. Hansen - the Sleek Veneer of the 1980s
    Dana@65, I describe Lindzen's as the worst of all the scenarios presented by you; even the massive overestimate that is Hansen’s Scenario A performs better. Scaddenp@64, my Figure@63 does show Dana's adjusted Scenario B with a sensitivity at 3. However, Scenario C with a sensitivity of 4.2 still gives a better fit with actual temperatures. I agree that the models use comparatively simple physics but this is also why they are extremely useful. There would appear to be something missing in the post-2000 behaviour of Scenario B that is (coincidentally?) captured very well in the excellent empirical performance of Scenario C.
    Moderator Response: [DB] And you base this on what model of EyecrometerTM...?
  47. Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
    TTTM, nature soaks up half of our emissions at moment. We dont have to go to zero. But you do have to start! The kill the subsidies, proposed at moment would be something. Extend it coal would be even more important. Real leadership in my opinion would be kill all subsidies on anything industrial, ban construction of new FF power unless emission sequestered and then let market figure out the best solution going forward. However, so far any attempt to wean off subsidied energy (which obviously means a hike in FF price) gets strenuously opposed. Let anyone pay (especially non-westerners and grandchildren) except us is catch-cry.
  48. TimTheToolMan at 14:43 PM on 5 May 2011
    Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
    Dana1981 writes "seems to also have missed this part of the article: ...Instead of committing ourselves to 2.9°C warming above pre-industrial levels as in business as usual, we're only committed to 2°C, which keeps us right at the cusp of the global warming "danger limit." Apparently you missed the ENTIRE following article that suggested that "goals of limiting human made warming to 2°C and CO2 to 450 ppm are prescriptions for disaster" And that Hansen says that even 350ppm is too much. Well we missed the boat on that one. And then Tom Cook believes, not in your article dana1981, but instead that we can effectivel reduce emissions to zero AND sequester ourselves back to 350ppm. And you think I'M ignorant of whats real?
  49. Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
    "Nobody likes being told what they can and cant do." And sadly, noone likes paying for the mess they have created either.
  50. Lindzen Illusion #3 and Christy Crock #5: Opposing Climate Solutions
    TTTM - when in human civilisation have we dealt with 1m in hundred years? Its already an expensive problem. Nightmare going forward. Chances of us getting in adaption money from polluters? nil. So far "my perspective" doesnt cut it for me. Can I go to city hall for that? Care to back that with proper analysis or is your perspective based on betting there won't be 1m in 100 years? Now if we weaned off CO2 emissions so that we could be confident that ONLY 1m sealevel was going to happen and that sealevel would stablise again, then I think we could live with it. Otherwise,1.5-2m in the next century means abandoning my city.

Prev  1723  1724  1725  1726  1727  1728  1729  1730  1731  1732  1733  1734  1735  1736  1737  1738  Next



The Consensus Project Website

THE ESCALATOR

(free to republish)


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