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  1360  1361  1362  1363  1364  1365  1366  1367  1368  1369  1370  1371  1372  1373  1374  1375  Next

Comments 68351 to 68400:

  1. Philippe Chantreau at 18:01 PM on 12 December 2011
    Plimer vs Plimer: a one man contradiction
    Mat L, what is the context on these? Does it include rock weathering, time scales, etc? As unlikely as it is, (pretty much impossible in fact) I would not be surprised if Plimer made the argument that, even if all the crust' carbon was released in the atmosphere (and that would be 11 times the quantity currently present according to him), some processes would remove the excess carbon so that atmospheric concentration would remain only at twice pre-industrial levels. I have not read the book myself (and I will not spend money to acquire it), so I have to rely on others' accounts. Plimer has held a lot of undefensible positions on this but nonetheless any accusation of self contradiction must be carefully weighted. In Monckton's case, it is obvious that he says whatever sounds plausible at the moment to meet the need of the argument. With this particular Plimer's pearl, it could be part of an internally consistent form of reasoning; as removed from reality as it may be, it would still be more honest than Monckton's spur of the moments falsehoods.
  2. Plimer vs Plimer: a one man contradiction
    Mat L at #23. "Plimer B "The total amount in known fossil fuel could only produce 11 times the amount of CO2 in the atmosphere". I note from the book p325, prior to the quoted sentence, that Plimer states "In order to permanently double the the current level of CO2 in the atmosphere and keep the oceans and atmosphere balanced, the atmosphere needs to be supplied with 51 times the present amount of atmospheric CO2." He then follows with the comment "Unless we change the fundamental laws of of chemistry and change the way in which oceans work, humans do not have enough fossil fuel on Earth to permanently double the amount of CO2 in the atmosphere." Further to Johnny Vector comment at #20, Plimer is of the view that at current CO2 levels, the majority of the warming occurs in the first 100ppm and that any warming after that is too small to be significant. (You also need to read all of page 278!).
  3. (Fahrenheit) 451 ppm
    44, Tom, As frustrating as current times are, and as both malignant and foolish as I know people have historically been, I am confident that we'll hold CO2 levels well below 1000 ppm. The evidence will not only be incontrovertible, but down right painful in about 20 years. At that time, the effort to get off of fossil fuels will then cause as much harm as anything else, because we'll have to get off of it fast. And we'll have pushed things way too far, and we won't be able to get off of it fast enough. Transitioning far enough away from fossil fuels is going to take a half a century, at least. But I do believe events will conspire to prevent us from being so abysmally stupid that we get anywhere near quadruple digit CO2. Unfortunately, I also believe that much lower levels are every bit as dangerous. Perhaps not Great Dying dangerous, but too dangerous to think about for too long.
  4. Global carbon emissions reach record 10 billion tonnes - threatening two degree target
    Solutions interalia: - 16% contributable to products used in the rich countries --> provide renewable energy technology at a price level of base-load power and add the difference in the price of the products. Consumer wise: if I have to pay for some carbon tax which goes I do not know or pay that same amount into a product where I do know. - China, India etc. can demand from any foreign operator that it has to supply xx% of its energy from a renewable source. So it can demand at least 16%. - Most developing countries are not stuck into some 150 year old distribution system loaded with stranded costs. Please do not load those countries with that ill-fated type of systems. - Forget about CAPEX and view OPEX. With the rapid changing technology of today your capital is out date within 7 years. Implement modular sizeable and many more actions...
  5. (Fahrenheit) 451 ppm
    Sphaerica @39, being somewhat pessimistic after the Durban result, I'll point out that there are sufficient reserves of fossil fuels to raise the CO2 content of the atmosphere to 4600 ppmv, or about four doublings over pre-industrial levels. It is unrealistic to expect all that coal (primarily) to be mined in under a century, but atmospheric concentrations of 1000 ppmv are certainly on the cards by the end of this century. Current policy is relying on their being no tipping point on natural carbon emissions to avoid going from the disasterous (which current policy seems intent on locking in) to the catastrophic.
  6. Galactic cosmic rays: Backing the wrong horse
    Eric #54, not only is there not strong evidence for a YD/GCR link, there is no evidence for a YD/GCR link. Your saying so does not count as evidence. We have a very plausible mechanism in place for the observed changes of C14 and of regional cooling, in the form of changes in oceanic ventilation driving changes in delta C14. Changes in oceanic circulation conveniently also help explain the see-saw effects between SH and NH cold periods (noted by scaddenp in #55). Why invent a cause that as yet has no connecting driving mechanism, and fails to explain all the evidence? The failure to explain the Laschamp anomaly is still not a help to your thinking. Why would it have no effect during a glacial phase? And you certainly cannot have any timelag (your #48), given that the few proposed (yet not demonstrated) mechanisms for a GCR-climate connection require it to be immediate.
  7. (Fahrenheit) 451 ppm
    skeptic.fr: "it is not unthinkable to imagine that there are adaptative capacities" Yeah. Foresight and planning, for instance. Unfortunately, these capacities tend to require accurate risk assessment, which is lacking on the "skeptical" side of the argument.
  8. (Fahrenheit) 451 ppm
    Sphaerica: you're absolutely right that the world was a different place; I was thinking conditions that existed back then (e.g. weaker sun as you pointed out, plus no mass deforestation) would mean CO2 feedbacks weren't as strong as they are now. As if permafrost melting wasn't bad enough, we have ozone damage to worry about too:
    High ozone concentrations can affect not only plant growth, but soil fertility. Plants exposed to low ozone concentrations normally metabolize a certain amount of carbon dioxide. They send carbon to their roots, and then to the surrounding soil. Microbes in the soil make use of this carbon. Plants that are exposed to high ozone concentrations metabolize less carbon dioxide, so less carbon is available in the soil, and fewer soil microbes grow and thrive. Microbial activities that result in soil enrichment and carbon processing decrease, with the result that soil fertility diminishes.
    Pretty obvious vicious circle there :( More fossil fuel burning = more smog/ozone = damaged plant life that can't scrub as much CO2 = even worse positive feedbacks That's what I'm trying to figure out; are we on a course where all the natural carbon sinks might very well get killed off, thus leading to a Venus-style runaway greenhouse effect.
  9. (Fahrenheit) 451 ppm
    Pixeldust - the Permian-Triassic Extinction is ill-suited as an analogue for our future, because it happened so much slower (1-2 billion tons of CO2 per year, versus over 30 billion tons today from fossil fuel-burning). So the current rate of CO2 release is 15 to 30 times faster than the Great Dying. See: Ocean Acidification in Deep Time -Kump (2010) But that's not quite an apples-to-apples comparison, because even though the rate of change was slower, it carried on for a very long time, and we don't have enough fossil fuels to replicate that experiment. The greatest problem is the speed of change is so great, that many plants and animals we depend upon for our survival will probably become extinct, before have they chance to adapt. Certainly that's what the paleo record tells us, rapid injections of atmospheric CO2 (and by rapid I mean slower than today's rate) lead to widespread extinction.
  10. Pete Dunkelberg at 14:51 PM on 12 December 2011
    (Fahrenheit) 451 ppm
    This new study looks at bunched precipitation on a very fine scale. This one is broad scaled. The bunched precipitation pattern seems to repeat itself from the global scale down to very small events, almost analogous to a fractal.
  11. Plimer vs Plimer: a one man contradiction
    More for the Mill: On the burning of fossil fuels: Plimer A: “If humans burned all the fossil fuels on Earth, the atmospheric CO2 content would not even double”. Heaven and Earth, p293 Plimer B: “The total amount of carbon in known fossil fuel could only produce 11 times the amount of CO2 in the atmosphere”. Heaven and Earth, p325
  12. (Fahrenheit) 451 ppm
    36, PixelDust, I wouldn't go nearly that far. Again, to some extent it is apples and oranges. The world was a vastly different place back then, with one giant land mass, different ocean circulation patterns, a sun that was slightly weaker, etc. But I don't think we could ever reach 2000 ppm. Civilization wouldn't last that long, even if we found enough coal and gas to burn. The one thing I do find interesting is that CO2 in the Triassic was basically 275 ppm (from what I've found... I'm not that familiar with the period). CO2 for that event seemingly increased to 2000 ppm. That's a factor or 7.78 times. The temperature increase was estimated at 8˚C. 8=Tsensitivitylog2(2000/275) gives a climate sensitivity of 2.79˚C... or roughly 3˚C. Funny how that number keeps coming up over and over again.
  13. Pete Dunkelberg at 14:04 PM on 12 December 2011
    (Fahrenheit) 451 ppm
    skept.fr @ 27 "...winners and losers in precipitation trends." That Climate Wizard map looks rather mild compared to this. Whatever the extent of drought in coming decades, considering drought alone overlooks global bunched precipitation. A few paper are linked here and there are more. The weather that seems to be coming at us is floods some places, (some keys to floods and excessive rain are here) drought some places and bunched precipitation (also not good for agriculture) in between. Winners may be scarce.
  14. Galactic cosmic rays: Backing the wrong horse
    Hmm, why would cooling start in SH and then end as NH goes cold? (Actually not an uncommon pattern). I think other explanation other than GCR remain a great deal more plausible. Also, the real question of interest, is whether the forces at play in these events could be still impacting modern climate. Very difficult to find evidence for that.
  15. Galactic cosmic rays: Backing the wrong horse
    Scaddenp, the difference between hemispheres reduces one of the explanations of the C14 spikes (suggested in 51 and 52). The GCR effects could vary depending on the amount of ocean versus land, but I have no information for or against that idea. Muoncounter no possible connection between magnetic reversals and solar inputs that I can imagine. The PETM magnetic reversal was isolated and probably just coincidence (see the chart in my post 53. Certainly the link from magnetic field reversals to climate is going to be very tenuous due to the rather short duration of the change as you point out.
  16. Galactic cosmic rays: Backing the wrong horse
    Eric#53: "in a very rough sense, more reversals (with coincident weakening) allows more GCR and more cooling." A geomagnetic reversal includes a period of time (decades? hundreds of years?) when the field is of very low intensity. If the GCR story is to be believed, these must be times of high GCR flux, cloud formation and significant cooling. However, Lee and Kodama 2009: report high-precision records of a magnetic reversal event at the Paleocene-Eocene thermal maximum (PETM), a cataclysmic global warming event initiated at 55.0 Ma. But that's the earth's magnetic field; GCR orthodoxy involves solar output - those FDs that are supposed to be harbingers of fewer clouds. Is there a connection between geomagnetic reversals and the solar wind?
  17. Galactic cosmic rays: Backing the wrong horse
    Because of the importance of C14 to dating, the isotope and its interactions have been very closely studied for a long time. Be10 is nowhere near as well understood and I have colleagues working on hard on it. If GCR is important to YD, then why is it decoupled between hemispheres? For the corresponding SH events, you have ACR (Antarctic cold reversal) started before YD and finishing as YD gets going. This is fascinating area of study but the collected evidence from both hemispheres I think supports the idea that these events, associated with deglaciation, have there origin in ice sheet dynamics and interactions with the THC rather than some external forcing.
  18. Pete Dunkelberg at 13:17 PM on 12 December 2011
    (Fahrenheit) 451 ppm
    I hate to add to the gloom but given that we are staying on a very high emissions schedule so far and given that we can't change everything in less than decades even when we really decide we must, CO2 may go to 600 ppm or more. This could start serious carbon feedbacks and bring PETM-like instability for a few million years.
  19. (Fahrenheit) 451 ppm
    For me, the biggest fear has been that we're duplicating the conditions that led to the Permian Extinction Event: Smoking Gun: Greatest Extinction in History was a Volcanic, Coal fired, Greenhouse Event Sphaerica, how would that fit in with your analysis here? Are the Siberian Traps eruptions the closest natural analogy to modern fossil fuel combustion? If so, assuming worst-case scenarios (human CO2 emissions continuing to grow, Arctic belching methane at an ever-increasing rate, natural carbon sinks overwhelmed or turning to carbon source, etc), how soon could a new, Permian-esque mass extinction start? Apologies for lack of scientific precision in my question; I'm coming at this issue from a layperson's perspective
  20. Galactic cosmic rays: Backing the wrong horse
    Thanks for the clarification Sphaerica. CO2 being "not a control knob" for preindustrial has a couple exceptions that Tom pointed out on the other thread. There are times when it was in the past along with methane. Muoncounter and skywatcher, I agree that YD is not strong evidence, but more study is needed to determine the causes which AFAICT remain unknown. Another bit of evidence for a GCR knob is LIA cooling although it coincides with decreased TSI as well. I don't think the Laschamp event is a good test of GCR impact since we were in a glacial state which was probably a somewhat stable state.
  21. Galactic cosmic rays: Backing the wrong horse
    Tom, thanks for the comment. Yes, GCR's + or - do not result in positive forcing sufficient to exit the snowball state. GCR is definitely not the control knob, but one of several. The main theory seems to be cooling from high GCR's. It seems to me a more precise theory is that high GCR's retard or preclude warming by other means. Looking at the earth's magnetic reversals, http://upload.wikimedia.org/wikipedia/en/c/c0/Geomagnetic_polarity_0-169_Ma.svg in a very rough sense, more reversals (with coincident weakening) allows more GCR and more cooling. Obviously earth's reversals are a small part of the modulation of GCR so not a strong connection. I was unaware of the complexities of Be10 and I am sure there are some for C14 as well. The correlation of low Be10 measurements with higher rainfall could explain some of the Mercurio chart and is worth looking into further.
  22. Galactic cosmic rays: Backing the wrong horse
    Eric#48: The last sentence of the Laken abstract sounds like the standard qualifier, YMMV, to me. What significance do you see in it? "A control knob need not be overwhelming and instant and this GCR link would be offset by oceanic cycles and other weather." If this so-called control knob is so easily offset, then why maintain that it is a 'control' of any kind? At best, it is a fine tuner. But you cannot suggest that a GCR-cloud mechanism, if real, has some sort of lag. Ionization and cloud condensation either makes clouds or it doesn't. "A large decrease in GCR flux appears necessary for deglaciation" Again, where is the evidence for this declarative statement? The YD is not without its own complexities, as reported by Hughen et al 2000: the Younger Dryas 14C anomaly, which is by far the largest of the last 15,000 years, is not matched in amplitude by corresponding atmospheric 10Be concentration estimates. Thus, available 10Be data do not support the interpretation of the Younger Dryas 14C anomaly as solely or mostly due to increased production. In order to promote the speculative GCR-climate connection into a 'control knob,' you'll need a lot more evidence, a mechanism and most critically, an explanation for the climatological non-event at the Laschamp GCR peak.
  23. Galactic cosmic rays: Backing the wrong horse
    Eric, you're making suggestions that GCRs drive deglaciation and the Younger Dryas, yet these are not supported by evidence or your references. What is your support for GCRs being necessary for deglaciation in our current geographic configuration? Why, when this configuration has lasted throughout the Quaternary, are glaciations and deglaciations timed with orbital forcing? An again, why does any noticed correlation necessitate a causal connection? Your assertion about GCRs and the Younger Dryas is unsupported by the Hughen et al 2004 article from which you take your graph:
    "Peaks in 14C are also reconstructed at 40 and 29 cal. ka B.P. and previously reported at 12 cal. ka B.P. (13), coincident with Heinrich events H4, H3, and H0 (Younger Dryas), respectively (35). These events may also have been associated with unusually large perturbations in ocean ventilation and sea-ice cover explaining “anomalously” elevated 14C at those times (23, 36)."
    The main hypothesis is that the radiocarbon plateaux are driven by oceanic circulation changes (Hughen et al 2000 is ref 13 in the above quote). There is also doubt about the Cariaco radiocarbon spike - Muscheler et al 2008 suggest that upper ocean changes in the Cariaco basin itself influence the record.
  24. Galactic cosmic rays: Backing the wrong horse
    48, Eric, For the record, I was saying the same thing that you are, that in those cases CO2 was an amplifier tied to temperature itself, and not a control knob. It's fairly well accepted that the trigger for the event was a change in orbital configuration that changed not TSI but simply the duration and strength of Northern Hemisphere summers, which in turn triggered the retreat of the ice sheets, reflecting back less sunlight (and in that way causing a lower TSI). The main issue in the glacial termination debate is the main mechanism for the abrupt surge in methane and carbon dioxide that let the whole thing get from "there" to "here." I should point out, too, that in this sense I'm simply using the term "control knob" in a different sense that Dr. Alley. It's still a "knob" in that it affects temperatures, but it wasn't a knob before 1751 because no intelligent civilization had until then been able to change CO2 in the atmosphere. From that perspective, no, it wasn't a control then, but it is now.
  25. Galactic cosmic rays: Backing the wrong horse
    Eric (skeptic), a few thoughts that I cannot follow up properly at the moment: 1) Shaviv's temperature reconstruction is almost certainly wrong, both because it has been shown to not compensate for the effects of changing ocean pH, and because it is incompatible with the record of Earth's cryosphere. The oxygen 18 record from Royer et al, 2004, essentially reproduced below, although from a different paper is Shaviv's record as corrected for pH. Further, if Shaviv where correct, the absence of glaciation around 200 and 450 million years ago is astonishing, given the temperatures relative to current global temperatures. 2) Further, given a GCR connection to climate change, it seems unlikely that the early Earth would ever exit a snowball state. Essentially, the early Earth had 70% of the current TSI. That also meant a weaker magnetic field, and hence more GCM reaching the Earth. The logical conclusion with both a weaker sun and higher cloud albedo due to GCM's is that a snow ball state would have been a permanent feature of the Earth's climate until at least the last 200 million years. 3) Finally, I am uncertain that you can simply assume Be10 cannot be a dependent variable for climate. Specifically, Be10 is formed by spalliation from Oxygen or Nitrogen. It is then washed from the atmosphere in solution. When a particular sediment dries, the Be10 is left behind in proportion to its concentration in the water. Intuitively, there are then two controlls on Be10 concentration. The rate of formation, which determines concentration in the atmosphere; and the rate of rainfall. Larger quantities of rainfall, by washing the Be10 out of the atmosphere more frequently, and with a larger volume of water would result in a lower concentration of Be10 in the water, and hence in the resulting sediment. Alternatively, dry times such as the last glacial, would result in higher Be10 concentrations. This is just a suggestion by me, and may be entirely wrong. It would, however, neatly explain the correlation shown by Mercurio, and explain why Be10 concentrations do not always vary with fluctuations in the Earth's magnetic field (as indeed, is shown by Mercurio during the last glacial), and also why Be10 and C14 concentrations do not always correlate.
  26. Galactic cosmic rays: Backing the wrong horse
    Muoncounter, the end of the abstract says "However, we note the detectability of any potential links is strongly constrained by cloud variability." A control knob need not be overwhelming and instant and this GCR link would be offset by oceanic cycles and other weather. You asked "Are you suggesting here that a change in GCR flux is necessary to initiate deglaciation? If so, why - and on what evidence?" A large decrease in GCR flux appears necessary for deglaciation in the current geographic configuration, but a spike can throw it off e.g. in the Younger Dryas (13ky bp) I admit this is not a particularly strong event, but I don't think it is pure coincidence that the 14C spiked then Y.D. took place.
    (from http://alliance.la.asu.edu/temporary/students/Phil/Hughen.pdf) Skywatcher, the GCR spike shown in #29 took place in full glaciation so I would not expect a GAT response. My purpose in resurrecting this thread was to respond to the claim in Spharican's latest post "It took an increase of 105 ppm, or a factor of 1.6, to get us from an "ice age" into the world in which we currently not only live, but thrive" As I said there, it took more than CO2, it required a control knob, with the 1.6x CO2 functioning as an amplifier. The control knob could be TSI, and not GCR as there is considerable overlap in their effects.
  27. (Fahrenheit) 451 ppm
    skept.fr @20, no national representative at Durban may deny the 2 degree C, 450 ppmv target, yet they have all just signed of on a deal that almost guarantees that we will exceed that target.
  28. (Fahrenheit) 451 ppm
    skept.fr#32: Withlock deals with fire's role as an ecological process; re-defining fire-regime triangles has nothing to do with this discussion. Customizing the settings on climatewizard.org is straightforward. One of the options in a drop-down menu under 'Measurement' near the top is seasonal, monthly or annual. "For 'winners' and 'losers', replace these undue notions by there will be 'regions with more/less precipitation and greening'." 'Winners' and 'losers' were your choice of words; their replacement with gentler sounding euphemisms is mere semantics. "many countries depend on regional and global trade rather than sel-sufficiency." That's the point - the global interdependency of the world food supply is exactly why there can be no winners. "it is not unthinkable to imagine that there are adaptative capacities" Imagine the cost when those 'capacities' need to be developed and brought online at short notice because we sat around, pacified by those who claim 'its not bad,' and did nothing. Seems like we've had this conversation before.
  29. (Fahrenheit) 451 ppm
    #30 scaddenp : I globally agree with you. AFIAK, UE negotiators accept the principle of 'common but differential responsibility' in AGW diplomacy. That's why the Kyoto Protocol or the 20-20-20 European climate plan are not bound to commitment by other parties, from Annex I or non-Annex I. And that's why the first, second and third world will not have the same reduction targets in an (hypothetical) 2015 agreement.
  30. (Fahrenheit) 451 ppm
    @28 muoncounter : "Other than the word 'fire' in the title, is there any relevance in the Withlock reference to this discussion?" Quite surprising, did you read the paper? In #21, you speak of climate change and fire correlation. Withlock et al 2010 have developments on weather/climate conditions of fire in climatic archives, but also on all factors influencing fire, including vegetation change. If you consider that as OT, then your #21 wat OT too. For 'winners' and 'losers', replace these undue notions by there will be 'regions with more/less precipitation and greening'. That was my initial point in #15, the idea that vegetation will regress globally does not seem to be supported by vegetation models coupled to AOGCMs. Don't understand what you mean by 'tweaking climate wizard settings a tad' and how you get summer (or any particular season) precipitation on this site. (For extreme events, I guess the recent SREX is the most updated reference of the expert view. There is just the SPM for the moment, where I read : "There is medium confidence that droughts will intensify in the 21 st century in some seasons and areas, due to reduced precipitation and/or increased evapotranspiration. This applies to regions including southern Europe and the Mediterranean region, central Europe, central North America, Central America and Mexico, northeast Brazil, and southern Africa. Elsewhere there is overall low confidence because of inconsistent projections of drought changes (dependent both on model and dryness index). Definitional issues, lack of observational data, and the inability of models to include all the factors that influence droughts preclude stronger confidence than medium in drought projections."). If feeding the world is "at risk" (for change in precipitation), I suppose the global primary productivity conditions in 2050 and 2100 is the most wanted information. Because even today there are deserts, droughts, etc. so agriculture adapts to changing conditions and moves if necessary, many countries depend on regional and global trade rather than sel-sufficiency. At least, it is not unthinkable to imagine that there are adaptative capacities in two or three generations (agriculture was different from now in 1970 or 1930). Conversely, feeding the world without directly or indirectly fossil-assisted technologies that sustained current productivity (mechanical engines, fertilizers, construction of irrigation and stockge systems, R&D biotechnology, etc.) is a challenge, and I'm quite surprised that nobody considers that there are some "risks" here too...
  31. (Fahrenheit) 451 ppm
    Sphaerica, this is the skeptic sight so I imagine one would be skeptical of post 26, but I have spent 40 years on it, and have a masters from UCI, so please consider it. May contact me at p*******y@gmail.com. I hope this is not breaking spam rules, if so please forgive me.
    Moderator Response: [Sph] E-mail address edited for privacy.
  32. (Fahrenheit) 451 ppm
    "But the same is true for US government choices " Yes, there is broad agreement that there is pain in the future but we dont know how much. Even when we are confident that future pain will be worse than taking action now, however, there is an extreme reluctance to do so. The west has no concept of the idea that since we caused a problem, then it behoves us to take responsibility for it, even if it causes us pain. In short, we want the rights but not the responsibility. For all the lip service to equity, there is no intention of giving it, unless a way is found to do so without reducing standards of living and growth in the west. Now I am all for maintaining my standard of living if a way can possibly be found to do so. I am not however prepared to compromise the future of my children and grandchildren to maintain that. Those pushing anti-science are. We need precautionary measures first and then see if we can find a way to prosper within those constraints. Instead negotiators are settling for wild hopes, and a refusal to accept constraints unless there is a way to do so without causing any rich person some pain.
  33. (Fahrenheit) 451 ppm
    skept.fr#27: Other than the word 'fire' in the title, is there any relevance in the Withlock reference to this discussion? "their will probably be winners and losers in precipitation trends." I love that kind of thinking. Tweaking sphaerica's climate wizard settings a tad, look at the change in precipitation in summer for a few of the other ensemble percentiles. The growing season across a wide range of southern Europe, the middle east and west/central Asia, South America, western North America, southern Africa and much of Australia is at risk. In that scenario, there are no 'winners and losers.' Displaced populations and pressure on world food supplies will show no favorites; it's naive in the extreme to think that 'it will be greener where I live' makes one a 'winner.'
  34. (Fahrenheit) 451 ppm
    Well presented Sphaerica with much to consider. I personally am most intrigued by the paleoclimate studies focusing on the mid-Pliocene around 3 mya to see what sort of climate we may be in for. In determining the overall impact on humanity three key issues are of course paramount: 1) The effect on the food grains. How will wheat, corn, etc. do in a warmer world? Might they survive but their prime growing regions be shifted? What about genetic modifications to these crops to make them more successful in a warmer world? 2) How will the world respond to and accommodate climate refugees? Mass migrations are possible, and this could lead to conflict if not managed well. 3) The biggest unknown is the response of the oceans. Rising oceans may play some role, though I think accommodations can be made to mitigate the worst, but more importantly is the overall health of the oceans in terms of the biological and ecological parameters. The ocean has this far buffered us from the greatest impacts from the large scale dumping of CO2 into the atmosphere. This buffering has taken place on two levels: the retention of excess heat and the direct uptake of CO2. So the big question is-- how will the the ecosystems of the oceans respond to being warmer and more acidic? The answer to this question is important, perhaps even key to the overall health of the rest of the planet.
  35. Galactic cosmic rays: Backing the wrong horse
    David Lewis' point at #29 above is worth referring to. If GCRs were any kind of a control knob, you'd expect a response around 38,000 years ago. Alley showed there wasn't and so GCRs don't control the climate.
  36. Galactic cosmic rays: Backing the wrong horse
    Seeing as nobody has demonstrated a mechanism to connect GCRs and Earth's climate, despite lots of effort, then Eric, your first sentence does not make sense. A good example is here - very few of the requirements for a GCR hypothesis appear to be working. Frankly, we can safely put that one in the hold alongside fairies changing climate IMHO. Also on your first sentence in #44 - if there's an increase in piracy alongside global warming, do you "have to agree that there is some causation that we don't understand"? Bit of a non sequiter. Your final sentence is correct, however!
  37. (Fahrenheit) 451 ppm
    #21 muoncounter : about fire in this particular sense (non metaphorical), see also this very interesting paper from Withlock et al 2010 . #22 scaddenp : I totally agree that the ‘equity issue’ (ie historical responsability of Annex I UNFCCC countries) is a basis for a future international agreement. But for that I read about BRICS’s position in COP or in their national climate plans, it won’t be sufficient : emerging countries are not just searching symbolic rewards, but primarily material developments for their people, the same material developments Western countries has already achieved. I hope non fossil energy will be able so sustain such a quest and I think it’s now a major point of reflexion. But the same is true for US government choices : pipeline from Canadian tar sands, deep offshore GoM, shale gas and oil won’t be given up because of the future (and still uncertain) cost of droughts in 2050s or 2100s, as the present (and certain) cost of their too rapid abandonment would be huge for a heavily fossil-dependent society like the US. Find substitutes (even 10% more costly for a carbon tax compensation) of the same amount, and you’ll find the solution. #23 Sphaerica : as your map for 2080s clearly shows, their will probably be winners and losers in precipitation trends. Same is likely true for vegetation growth capacity (precipitation skills of models are still poor, but it is the best we have). That’s why I consider the Fire Age analogy as a good metaphor for regional changes (including probably France ‘sud de la Loire’), but not global changes. Anyway and beside the metaphor itself, concerning human choices in the 2010s, I think these two-generations-from-now predictions can not be considered as ‘killer arguments’ in the climate debate. For an example : Spain is a already a semi-arid country who, like others here in Europe, has known a strong warming in the past 30 years (approx 0,5K/dec since the mid-1970s for Spain, if I remember correctly). But in the same time, Spain is a leading exporter of fruits and vegetables and its most productive regions are in the warm South of the country (intensive hydroponics cultures adapt to climate variations, which change mainly the season of growth : in a warmer climate you get the first strawberries in march rather than april, february rather than march, etc.). I think there is a kind of ‘basic instinct’ for such short term adaptations to change and it is very difficult to fight that psychological bias, even with the scariest projections. And for my part, I refuse to endorse particular projections without mentioning their relative level of confidence or the existence of opposite view in the literature (I mean the ‘serious’ view in the 'serious' literature). That’s why IPCC reports are my ultimate reference because it’s their job to check all publications on a subject and to give an informed assessment on what we know. But mainly, my basic point is that such long term predictions are no more at stake in climate negotiations. I’m pretty sure nearly all negotiators have these kind of risks in mind, even before Durban COP17. But they have other risks in mind too for their socio-economic pathways, and that’s why they probably refuse a too fast or too constraining treaty (particularly if they benefits of very cheap energy as producers of coal, gas or oil, of course). But of course, our discussions have their own interest, as we can compare and evaluate our views on climatic change.
  38. (Fahrenheit) 451 ppm
    Wonderful clarity and completeness. Can I have permission to add this to my book as an appendix. It would be a wonderful convenience, rather than just the URL reference. My book proposes a solution based on use of the energy of latent heat in the atmosphere to resolve, energy, water, and land problems--- thus all commodities at once. Thanks, Atanacio Luna
  39. Galactic cosmic rays: Backing the wrong horse
    Eric#44: "you have to agree that there is some causation that we don't understand" Isn't the entire GCR argument based on 'some causation we don't understand'? "lower GCR's and corresponding higher TSI allow warming to take place, otherwise, for the most part, we would be stuck in a glaciated state" Are you suggesting here that a change in GCR flux is necessary to initiate deglaciation? If so, why - and on what evidence? Why isn't it simply sufficient for a change in TSI to start the warming process? "GCR appears moot in our current interglacial because it does not seem to happen in reverse" An odd sort of control knob, only working one way. That is not how I recall the Svensmark model - more solar, fewer GCRs, fewer clouds. Less solar, more GCRs, more clouds. That has to work both ways. A recent paper, Laken and Calogovic 2011, is relevant: We find no evidence that widespread variations in cloud cover at any tropospheric level are significantly associated with changes in the TSI, GCR or UV flux, and further conclude that TSI or UV changes occurring during reductions in the GCR flux are not masking a solar - cloud response. How is that a control knob?
  40. Galactic cosmic rays: Backing the wrong horse
    muoncounter, if you agree that it is "pure correlation without a mechanism", then you have to agree that there is some causation that we don't understand or simply the coincidental and complementary TSI changes. My sense is that the lower GCR's and corresponding higher TSI allow warming to take place, otherwise, for the most part, we would be stuck in a glaciated state in our current geological configuration. GCR appears moot in our current interglacial because it does not seem to happen in reverse (higher GCR's and lower TSI predictably causing cooling). Obviously the GCR/TSI knob, such as it is, is completely moot in light of our increasing GHGs. Our only worry right now is warming from GHGs.
  41. (Fahrenheit) 451 ppm
    I think newscrusader's point was that I was actually being generous by hoping that we'll simply hold emissions constant and thus forestall 451 until 2042. Obviously continued economic growth in India and Asia could even offset global efforts to reduce emissions in other ways, and hence lead to a higher annual emissions and reaching 451 more quickly. Honestly, things are already bad enough. I felt like I was pretty even handed in presenting the possibilities, without even being realistic about things such as increases in annual emissions. But for myself, I just didn't want to think about getting to 451 before 2042.
  42. Baked Curry: The BEST Way to Hide the Incline
    Judy Curry made a revealing comment at the AGU 2011 conference on Wednesday morning, in the ED32A session at 10:20. In her presentation she erected a straw man that previously, climate scientists have communicated only one-way with the public and policymakers, not listening to responses, not being open to ideas from those audiences, and not engaging in conversation. Then she described her approach as differing from everyone else's--as engaging in real, looping, conversations. There was time for only one question from the audience, and nobody used that to challenge her with the many blogs that have robust commenting with responses, and with the multitude of public lectures that include extensive discussion with the audiences. Her image of how teachers teach is bizarrely, stereotypically wrong. An accessible example is David Archer's free videos of his lectures in which he always takes questions and engages in discussions with his students. The one question the audience did ask was more revealing. Steve Easterbrook posed: If your students were discussing amongst themselves, but the information they were presenting to each other was wrong, wouldn't that reinforce their wrong ideas? Curry responded tellingly, that she views her job as being only to facilitate discussion among students, not to correct or direct them! I find that astonishing for a teacher of a scientific discipline. I don't know why she continues to be employed as a teacher. Apparently she runs her classes the same way she runs her blog.
  43. (Fahrenheit) 451 ppm
    @newcrusader Never heard about exponential functions (e.g. compounded interest)? If you add to a solution, the concentration grows exponentially. Actually any kind of growth is exponential => Growth is an Exponential Function
  44. (Fahrenheit) 451 ppm
    20, skept.fr, You are missing the point of the "Fire Age" analogy. The planet may well green overall, given enough time. But critical, agriculturally productive and heavily populated areas of the planet are in serious danger of suffering the opposite. Consider this prediction of precipitation changes (ensemble average for the Medium A18 emissions scenario) from Climate Wizard: I think the odds are stacked very heavily against Texas, Southern California, Mexico, Spain, Italy, the Balkans, Israel, Egypt, South America and others. Large parts of the northern USA, Canada, far northern Europe, Asia and others may well see a greener world. But some very basic parameters look to combine to make those particular changes fairly likely. Everyone is going to experience the upheaval of change, however, and that is the main point. The world is going to change, probably more quickly than people expect, and that is going to be both expensive and painful (in a real, personal sense for too many people). It doesn't really take much beyond common sense to look at things at a high level and to say that it is not worth the risk. Not when inexpensive, coordinated, moderate action now is capable of keeping the situation under control with far less expense than is seemingly inevitable given a continuing course of almost inaction. From the perspective of actual, living people and today's civilization, the term "Fire Age" may well seem appropriate.
  45. Plimer vs Plimer: a one man contradiction
    @John Cook: Re the first sentence of the final paragraph of your article, how would one "...pore through Professor Enting's thorough document..."?
    Moderator Response: [JH] I'm wiping the egg off my face. For my entire lifetime, I thought the phrase was "pour through." I guess I've never seen it in print before now.
  46. (Fahrenheit) 451 ppm
    Well I would agree wholeheartedly that "emerging" countries want to escape poverty and need to be more energy intensive to do so. On the other hand, they are the most vulnerable to rapid warming on the whole. The killer in this, is that Western world created the problem but is extremely unwilling to commit to change or to pay for consequences. While the western world won't make meaningful change, the rest of the world wonders why they should be making the sacrifices instead. Worse still, the countries with the highest historical contributions to elevated CO2 are also least affected. It swings on the question of equity. At present, dealing with a generational level problem, the world is committing to go to hell in a handbasket rather than face up to the equity issue. A frankly, I think the major sticking point for a democracy like US, is the denial of science by Republicans. This constrains what any negotiator can sign for and while the US wont make concessions, you can bet your life that China and India wont.
  47. (Fahrenheit) 451 ppm
    skept.fr#20: "excessive metaphor of 'Fire Age' against misleading horizon of 'Green Paradise' is mostly a low-effect rhetoric game" It would be nice if that was only a metaphor. Marlon et al 2009 find paleo correlation between rapid climate change during recent de-glaciation and fire activity in the US: Intervals of rapid climate change at 13.9, 13.2, and 11.7 ka are marked by large increases in fire activity. The timing of changes in fire is not coincident with changes in human population density or the timing of the extinction of the megafauna. Although these factors could have contributed to fire-regime changes at individual sites or at specific times, the charcoal data indicate an important role for climate, and particularly rapid climate change, in determining broad-scale levels of fire activity. Marshall et al 2008 make a case for increased fire frequency as temperature/precipitation events become more erratic: As climate change continues, we can expect increased precipitation variability (ie more frequent wet-and-then-dry periods). In addition, fuels are already being dried by earlier snowpack disappearance, earlier commencement of transpiration, and higher temperatures. Such changes in fire frequency or intensity are almost certain to influence ecosystem structure and function. If you've lived through a fire season, you'll agree this is no rhetorical exercise.
  48. (Fahrenheit) 451 ppm
    Sphaerica : the papers I linked did not deal with long term equilibrium sensitivity ("a few thousand years"), but with near term CO2 doubling or 2100 projection in a A family scenario. I've personally no prior assumption about greening or non-greening world, because there so many factors to be considered in plant growth (CO2, T, water, nitrogen, etc.). That's why I rely on vegetation-GCM models as best estimates of our current understanding. More broadly, I understand you're scare to death but as Durban COP17 ends, my own reflexion was that 'scary scenario strategy' is quite unable to accelerate political decisions, and will probably be as unable in the near future. First because the more scary are your projections, the more uncertain they (usually) are, so you expose yourself to the suspicion of unbalanced view. Second because India, Brazil, Indonesia and dozen of emerging countries do not basically object the reality of climate change (and the eventuality of huge and fast regional changes). No, they want to escape poverty, so as Western societies did thanks to fossil energy and the 120 ppm added to atmosphere since the 19th century (these 120 ppm are not just radiative forcing, they're also the historical witness of Western access to welfare). Give solutions to do so without relying massively on oil, coal and gas, and scary scenarios will be perfectly useless because climate targets will be fully compatible with development commitment. I think it is the Gordian knot in the new era of climate debate, as denial of basic science looses its (already low) influence except on the right wing of Republicans. And conversely, I think excessive metaphor of 'Fire Age' against misleading horizon of 'Green Paradise' is mostly a low-effect rhetoric game. No national representant at Durban denies the 2K / 450ppm target as a necessity from a climatic point of view, and it means all national representants grossly agree with adverse effects of a too fast and huge warming you describe here. That is no more the central point IMO.
  49. (Fahrenheit) 451 ppm
    Surely this should be forwarded for publication in a proper journal. It just might concentrate the minds of those that think we can relax now that we have a global agreement on CO2 reduction and can't hear the deafening clatter of the can being kicked down the road, yet again.
  50. (Fahrenheit) 451 ppm
    lovelock did this simple modelling awhile back and has written a number of books in plain english on what this warming means.

Prev  1360  1361  1362  1363  1364  1365  1366  1367  1368  1369  1370  1371  1372  1373  1374  1375  Next


The Consensus Project Website

THE ESCALATOR

(free to republish)


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