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  1864  1865  1866  1867  1868  1869  1870  1871  1872  1873  1874  1875  1876  1877  1878  1879  Next

Comments 93551 to 93600:

  1. Blaming the Pacific Decadal Oscillation
    johnd - I'm not certain I can follow your logic there. Water vapor rising into the atmosphere reaches a point where the air is cool enough to condense it; cooler than the water vapor. When it cools and condenses the energy involved in that transition is given over to the air, which warms. That heat energy is not inconsiderable - the updrafts in thunderstorms and hurricanes are driven by the heat from condensing vapor. The downdrafts are considerably cooler. Thunderstorms end when there is insufficient moist air drawn in, hurricanes weaken when they get over land and lose the warm moist air over the oceans as an energy source.
  2. Interactive animation of the climate change impact on agriculture
    Yes, I have something to add Daniel. The timeing of any heat units is critical to how plants respond. Without knowning the underlying metrics that this model is based on, the model us quit useless. The IPCC model is not temperature specific. I will use one crop as an example: Wheat. Wheat likes cool weather when it is tillering. Once tillering has completed, it likes warm weather. Flowering wheat, which is the reproductive period, likes dry weather as any moisture contributes to leaf disease and fusarium. Once wheat has finished flowering, a shot of rain is good and warmer temps once again are desired. It is about timing of heat units. I was not surprised to see a rise in production from more warmth. That is pretty much a given. The added co2 also contributes to a rise in production. Without more information on how this program was constructed it is impossible to see if the results are credible. As a side note, I am a farmer. Hence, I recognize what is required.
    Moderator Response: For some scientific studies of the effects of CO2 and heat, see the summary by the U.S. Dept. of Agriculture, and other studies, linked in the comments of the thread "CO2 is not a pollutant."
  3. The Climate Show Episode 8: Kevin Trenberth
    The problem with 'super microbes' is that they're very hard to turn off when you've reached your target CO2 concentration, whereas industrial plants you just flick the switch... Well, I stayed up well past my bedtime to watch/listen to the show, and it was well worth it, thanks. I did note with interest, however, the discussion of the new process for capturing atmospheric CO2 using a solid amine structure, with low temperature release. This sounds ideal for a solar-powered carbon capture factory (in fact the New Scientist article quotes a figure of perhaps a million tons per day from a commercial plant - that's almost enough to capture the entire CO2 emissions from Australia, from just one plant!) The other part of the equation would then be doing something with that CO2. There are solar thermal methods to combine it with H2O to form CO + H2 + O2, to give a hydrogen feed, and the CO can be further fed into other processes to produce hydrocarbon fuels. But if the aim is to sequester the carbon, you'll still need to find something to do with the CO or subsequent hydrocarbons. It would be somewhat ironic if we ended up synthesising heavy oils, only to pump them deep underground into deplete oil reservoirs... Expensive? Sure. But what adaptation measure isn't?
  4. Arkadiusz Semczyszak at 01:14 AM on 8 March 2011
    A Real-World Example of Carbon Pricing Benefits Outweighing Costs
    I, as a resident of a country whose huge areas were destroyed by the coal mines - I - the "great enemy” of fuel industry based on coal and petroleum - would that it disappeared as quickly as possible. However, energy-saving technologies and renewable energy sources requires time and large financial outlays. Even - a relatively modest effects - was founded in Kyoto - but require very fast action. Beyond a certain amount of CO2 in the atmosphere, the need for several thousand. years to the biosphere can remove the surplus. Loss of Carbon from the Deep Sea Since the Last Glacial Maximum, Yu et al., 2010..: “Combined benthic δ13C and [CO3 2-] results indicate that deep-sea-released CO2 during the early deglacial period (17.5 to 14.5 thousand years ago) was preferentially stored in the atmosphere, whereas during the late deglacial period (14 to 10 thousand years ago), besides contributing to the contemporary atmospheric CO2 rise, a substantial portion of CO2 released from oceans was absorbed by the terrestrial biosphere.” Rapid reductions in CO2 are achievable only through widespread application of CCS - global CO2 emissions growing rapidly - especially in China. CCS will surely raise the cost for energy - this is not possible that improved energy efficiency. This is after all only a mere storage of CO2. CCS "will take" a large part of investment in renewable energy sources. Even more (and more) will make us from the fuel concerns - energy supplies based on fossil fuels. Corporations such as Statoil and Shell - has for many years - in Europe - the fund's most "alarming" researches on current and future GW. CCS will give preference position - particularly in the U.S. - the big oil corporations (this is the expensive technology - that she was a fully secure.) Their leaders already argue that the large-scale introduction of CCS - that gives you the quasi-monopoly position - will be able to run a cost-effective production of energy from methane clathrates (including liquid fuels production - their price at CCS will have to be higher.) Methane clathrates will be "sufficient" for USA on 3,000 years ... At the CCS we can (for a long time), forget about "peak oil" and "clean energy" ...
  5. The Climate Show Episode 8: Kevin Trenberth
    Bern: “I'm talking about plants to capture CO2 from the atmosphere to reduce concentrations to a "safe" level.” Bern, of course, is talking about industrial plants. Living biological plants do this all the time; it’s where the fossil fuels came from originally. Might we someday genetically engineer some super microbe to accomplish the desired task? Hopefully it won’t entail covering our oceans in a green slime.
  6. A Real-World Example of Carbon Pricing Benefits Outweighing Costs
    Gilles, "health and welfare are POSITIVELY correlated with the use of fossil fuels, and that without carbon, there is nothing but the poorest life you can imagine." Well apart from general well being index and mental health of course.
  7. Interactive animation of the climate change impact on agriculture
    Of course, it is also critical to notice that the temperature change in the thermometer is *local*, which means that my earlier reading was not actually so misleading after all! A *global* temperature rise of 1ºC is probably sufficient in most areas to push *local* land-based temperature rises above the point of where crop effects are positive or neutrality and into deficit, since (a) local temperatures over land increase faster than over oceans and (b) local temp rises generally increase relative to the global average for higher latitudes (especially in the Northern Hemisphere). So in terms of the big picture, going much beyond a 1ºC global rise would likely mean net crop losses, even with adaptation.
  8. Interactive animation of the climate change impact on agriculture
    (When I speak of crops going well, I meant in comparison to my impression from having read a bit on this topic previously. Obviously, after a certain point things are grim no matter how well we adapt. It was just that that point was a little higher than I had previously thought.)
  9. Interactive animation of the climate change impact on agriculture
    What surprised me was how well crops did, especially at higher latitudes. I was under the impression that almost any temperature rise was bad for agricultural output in the tropics and almost anything much above 1ºC was bad in temperate regions. It would be useful to know the percentage of global production found in each of the two regions, in order to be able to calculate the global effect of different temperature changes. Also, is this only for the Northern Hemisphere? Or is the graphic simply misleading?
  10. A Real-World Example of Carbon Pricing Benefits Outweighing Costs
    "If I am getting latent heat from the environment that allows me to turn my furnace off, I am now emitting less CO2". Wow, so its OK to mess with the atmosphere just so you can claim you're consuming less fuel in winter? Here's an idea-try insulating your home or-heaven forbid-where a jumper indoors, that'll cut your fuel bills more than milder winters. You are also aware that you can heat your home with an A/C or with relatively clean landfill gas? Also, try living here in Australia where every Summer we're getting increasing number of nights that are *above* 20 degrees C-thus forcing us to consume more electricity to keep our homes cool at night. As I said above, RSVP, you've long since reached the point where you actually *detract* from the debate, rather than contribute anything meaningful. Personally, I think you should refrain from posting until such time as you're prepared to say something....I don't know....moderately *intelligent*?
  11. Blaming the Pacific Decadal Oscillation
    johnd at 16:37 PM on 7 March, 2011. You appear to be giving yourself contradictions by thinking of water droplets as not part of the air - surely what is crucial is that they are there in the atmosphere, and probably at equilibrated temperature with the air. The water vapour forming droplets releases heat into the atmosphere, which necessarily increases the atmosphere's temperature. That heat has been carried from the surface liquid water into the atmosphere by the evaporation-condensation cycle. So the bottom line is that it warms the atmosphere.
  12. A Real-World Example of Carbon Pricing Benefits Outweighing Costs
    rsvp, but that's where you live. Try it in a city which regularly has several days in succession over 35C. All you need to do is look at how a "heat wave" is defined in different locations. Here it's 5+ days over 35C or 3+ days above 40C. Other places have other definitions. I can assure you that a summer with no heat waves can still rack up an impressive total of weeks requiring a lot of air conditioning unless the household has done some serious work on passive cooling. And it is much, much easier to warm people (at least enough to maintain life) during cold weather than it is to protect from life-threatening heat.
  13. A Real-World Example of Carbon Pricing Benefits Outweighing Costs
    RickG #74 "You have data showing global fuel consumption is decreasing? Or am I asking an inconvenient question? " Global fuel consumption may be increasing, but it is not due to warming. The inconvenient answer is that my personal winter bill has increased while consumption has actually gone down. Marcus #75 If I am getting latent heat from the environment that allows me to turn my furnace off, I am now emitting less CO2. My air conditioner on the otherhand happens to run off of electricity (maybe yours is different). I also only have to turn on this airconditioner about three days in the summer at most, whereas heating is big deal and must be going for at least four months.
  14. Interactive animation of the climate change impact on agriculture
    I should have said in 4 that the temperature can be set to zero temperature change, rather then zero temperature.
  15. A Real-World Example of Carbon Pricing Benefits Outweighing Costs
    "OK Marcus, so how is the electric car of your friends working ? " Man, this is such a pointless question Gilles-it seems to imply that the "wrong" answer will invalidate my basic premise-which is that our current transport network represents a massively inefficient use of a rapidly declining resource. Or are you trying to suggest that people sitting in bumper-to-bumper traffic, consuming 1/5th of the petrol in their cars to go *nowhere* is a good thing? As it happens, most of my friends either use buses/trains like me-or get around by bike. Those friends of mine who do have electric cars are very happy with their purchase, as they've seen a significant reduction in their maintenance & "fuel" costs.
  16. A Real-World Example of Carbon Pricing Benefits Outweighing Costs
    Come on Rick, we all know that RSVP has nothing of value to add to this debate. He seems to forget that the flip-side is too much heat in Spring & Summer, & reduced rainfall too-which will of course hurt agriculture. Hotter Summers will also result in greater fuel consumption as people try & keep cool. Given that its harder to get cool than warm up, this will have definitely lead to a net *increase* in fuel consumption over the course of any given year. So not only is RSVP's question totally pointless, it's also based on a total *falsehood*.
  17. A Real-World Example of Carbon Pricing Benefits Outweighing Costs
    @ 73 RSVP Really! You have data showing global fuel consumption is decreasing? Or am I asking an inconvenient question?
  18. Interactive animation of the climate change impact on agriculture
    DIkran: "Nobody thinks that model output is data. Models exist to demonstrate the consequences of a set of assumptions." I'm stealing that sentence for my thesis! Seriously, no-one *should* mistake model output for data but you'd be amazed (or maybe you wouldn't) how muddled people's thinking is on this.
    Moderator Response: [Dikran Marsupial] Glad to hear I have done something useful this morning! ;o)
  19. Interactive animation of the climate change impact on agriculture
    Maybe my eye sight is worse than I thought. But the variable is temperature, in fact the text says: Mean Local Temperature Change. Which suggests to me that the interactive educational tool is designed to show what would happen with a temperature change. Indeed, I can reduce the temperature to zero. Possibly the only fault is that it doesn't go into negative temperatures. Given that the vast majority of scientists understand the physics of temperature change and the effects. I would think the results are obvious. After all is it not skeptics that attach great meaning to the ability of growing grapes in different climates? Or are comments 1, 2 and 3 suggesting skeptics are using a poor metric for judging climate?
  20. Icing the Medieval Warm Period
    "No subtraction is being done. " By "subtraction", I mean switching off the anthropic forcings in the runs. Is it what is done, or no? If yes, I repeat : the fact that you worsen a fit by switching off a component AFTER you have adjusted your fit to data is not surprising : it is always true. And it is hence not very useful to "prove" anything on the validity of your model. "GCMs are not statistical model fits, they are models of the physics, that allow you to find out the consequences of a set of assumptions regarding climate physics." DM : we saw in the post about sensitivities that there was still a fairly large range of different sensitivities compatible with the data (or they would be dismissed by them). Do the "different curves" used to generate this interval include all these values of sensitivities, yes, or no ? and if yes, how can they all be "equally true" ? If you can explain the same data with different physical models, you're pretty sure that they are almost all (but one) wrong. And you cannot exclude they are all wrong. This is not a situation usually associated with a "well understood" theory.
    Moderator Response: [Dikran Marsupial] You are assuming that the model with only non-anthropogenic forcings was not independently "tuned" (as far as tuning is possible). I doubt that is the case. As I said, the GISS Model E code is freely available, so you can always go and check for yourself. Secondly, the diagram shown was not meant to "prove" anything on the validity of the model. If there is a large range of sensitivities that are compatible with the data, that suggests that the models would be relatively insensitive to their adjustment. Lastly, no, all models are wrong (GEP Box); nobody expects any of them to be exactly right. The question is, are they sufficiently right to be useful. YOu have yet to provide any evidence that they are not useful, we all know they are "wrong", that is entirely uncontraverisal.
  21. A Real-World Example of Carbon Pricing Benefits Outweighing Costs
    If winters are tending to be milder, it means the planet's energy efficiency has increased and thereby lowering average fuel consumption. Why is this fact always overlooked...or is this a sorely "inconvenient truth"?
  22. Dikran Marsupial at 19:38 PM on 7 March 2011
    Interactive animation of the climate change impact on agriculture
    As we have no data for future climate (as it hasn't happened yet), please explain how we can forecast the effects of climate change on agriculture without a model? Nobody thinks that model output is data. Models exist to demonstrate the consequences of a set of assumptions regarding climate physics; they also allow our understanding of climate physics to be falsified, by making testable predictions. Disregarding any argument just because it involves the use of models is deeply unscientific.
  23. Icing the Medieval Warm Period
    Daniel: with reference to your moderator replies to comments #15 and #24 - here is the url for the original temperature anomaly graphics: earthobservatory.nasa.gov Of relevance to modern temps vs MWP is the recent paper Recovery mechanisms of Arctic summer sea ice. S. Tietsche,1 D. Notz,1 J. H. Jungclaus,1 and J. Marotzke1 The paper states clearly that temperatures in the Fram Strait are higher than at any time in the last 2ky - including the MWP. Tietsche_GRL_2011.pdf
    Moderator Response: Hey, Welcome to Skeptical Science! Thanks for the link to the graphic (I haven't yet had the time to search for it, so many thanks)! Far be it for me to correct you, but I think you may have meant Spielhagen et al, 2011 wherein they present a 2,000 year marine sediment proxy record showing the unprecedented warming of which you speak. BTW, if you want to link to your website, please do so as many of the regulars here would find it invaluable. Thanks again!
  24. Interactive animation of the climate change impact on agriculture
    The supposed underlying data ref IPCC is based on models which is based on more models. That is what I meant by underlying data. Models are not data but only assumptions.
  25. Interactive animation of the climate change impact on agriculture
    Without knowing the underlying data used to make this little program, the results are pretty much worthless.
    Moderator Response: [Daniel Bailey] Do you have something constructive to offer besides the obligatory drive-by handwaving? As it stands, your comment contributes nothing to the dialogue on this thread.
  26. Blaming the Pacific Decadal Oscillation
    This is a most interesting topic and one which I think addresses a critical point about the climate system's response to certain forcings. It's very refreshing to see such an informative discussion which is purely objective and devoid of any personal attacks or sarcastic remarks, unlike some other sites. I'm a skeptic of AGW but always enjoy reading here because the debate is civil and friendly. This site's comments section is arguably the best for a balanced and thorough examination of the science.
  27. The Climate Show Episode 8: Kevin Trenberth
    I forgot to add - I'm not talking about plants to capture CO2 from fossil fuel burning - I'm talking about plants to capture CO2 from the atmosphere to reduce concentrations to a "safe" level. Perhaps enormous factory ships, sitting in the relatively calm & sunny equatorial waters? Capture the CO2, crack it in solar furnaces, compress to briquettes of carbon, and dump overboard to the deep ocean... How long would it stay there, though? Would, say, briquettes of graphite be gobbled up by some bottom-dwelling bacterium, and turned back into methane or CO2? And if it was, how long would it take that gas to make it back to the surface from the abyssal waters?
  28. A Real-World Example of Carbon Pricing Benefits Outweighing Costs
    OK Marcus, so how is the electric car of your friends working ? Dana : "we must find a new energy source to replace carbon fuels. Period. So, why aren't we looking?" We are looking. There's solar (PV and concentrated thermal), wind (offshore and onshore), geothermal, tidal, etc. etc. gasp. Oil is no more used for electricity, at least in the countries that can afford these expensive means of productions. Oil is needed for transportation, heating, carbochemistry, and all this won't help much. "Californians use less per capita energy than most of the rest of the USA, " mainly because climate is hotter, maybe ? "The scientific evidence is what it is, and it clearly shows that carbon is a threat to humanity." The first scientific evidence is that ALL indicators or wealth and welfare are POSITIVELY correlated with the use of fossil fuels, and that without carbon, there is nothing but the poorest life you can imagine. Mucounter : "You seem to be arguing against doing anything because in your opinion, nothing will be an equitable fix. " You misunderstood me : I am arguing that we MUST do anything we can to spare FF, first because they are being exhausted (and even if CO2 had no IR absorption line), but that this will not reduce the overall amount we will extract in the future.
  29. The Climate Show Episode 8: Kevin Trenberth
    Chemware - yes, I'm well aware of the energy costs - I would expect the capturing & cracking to be powered by nuclear or solar means (I seem to recall watching a video of a concentrator dish that was used in experiments to crack CO2). I completely agree that the carbon capture & storage (CCS) is a fool's errand that will consume enormous resources (both in money and engineering resources) that would be better spent on developing alternative energy supplies. After all, a reduction of, say, 10% emissions now (due to CCS) might cost as much as developing alternate energy sources that can cut emissions by 90% in the near future. It seems that, given limited funds, we should take the longer-term view - especially as, after spending the money on CCS, we'd then need to spend it *again* on the alternate sources anyway...
  30. Icing the Medieval Warm Period
    "The second graphic Tom Curtis shows here is the result of multiple model runs using various forcings. " Another strange thing : it is unusual to cover an experimental curve with a set of DIFFERENT models. Through the use of multiple wrong models, I can always cover everything in their interval. What does it prove ?
    Moderator Response: [Dikran Marsupial] It isn't at all unusual (in fact it ought to be standard operating procedure). The purpose is to show the uncertainty in the projection/hindcast based on our current understanding of climate physics. Climatologists are generally very happy to talk about model uncertainty; if they only showed the best model fit, they would be accused of cherry picking. BTW GEP Box said "all models are wrong, but some are useful"; you have asserted they are wrong, but have provided no evidence that they are not useful.
  31. Icing the Medieval Warm Period
    Mucounter : Tom and myself were obviously talking about the first graph (the NZ trend), because he introduced the sentence just before showing it. Concerning the "conspicuous rise " in the high southern latitudes between 1930 and 1940, I don't see how to blame anthropic forcings for it : did anthropic forcings really rise more in this period ? KR : as you probably know, all these models have free parameters, especially for clouds, and the outputs are selected by some kind of "best fits". So it's not the same to do a "best fit" without anthropic forcings, and to do a best fit with anthropic forcings and THEN substract them. Now you may also know that if I had added new free parameters, I would always improve the fit. I could improve the fit with natural forcings only by adding the position of Jupiter, Saturn, and Pluto, and then argue that if I substract these influences, the fit is worse. That is mathematically perfectly correct - and yet physically absurd. This is not a correct way of reasoning.
    Moderator Response: [Dikran Marsupial] No subtraction is being done. The breadth of the error bars tends to be due to the variability in model runs, not the variability in parameters. GCMs are not statistical model fits, they are models of the physics, that allow you to find out the consequences of a set of assumptions regarding climate physics. The degree to which they can be tuned is fairly limited. If you (or anyone else) think the observed 20th century climate can be modelled without anthropogenic climate by adding a few parameters, go for it, the source code of the GISS model E is publically available as a starting point. If you had to include the positions of Jupiter etc. to do so, that would just indicate that anthropogenic forcings are important; there is good evidence that carbon dioxide is a greenhouse gas and affects climate; that is not the case for the position of Jupiter!
  32. Timothy Chase at 17:18 PM on 7 March 2011
    Blaming the Pacific Decadal Oscillation
    nofreewind wrote in 76:
    Are the graphs of global relative humidity here right? http://www.friendsofscience.org/assets/documents/The_Saturated_Greenhouse_Effect.htm
    "The Saturated Greenhouse Effect?" The greenhouse effect wouldn't be saturated if CO2 were more than 50X its current concentrations. But for the crayola colors and line thicknesses and the exaggerated scales they appear to be similar to what you found at Climate4You. However, even if one takes at face value a drop in relative humidity that absolute humidity would appear to rise. Moreover, Chris Colose has pointed out that the reanalysis products this is based off of aren't of the highest quality. He states:
    Radiosondes provide water vapor information in the atmosphere since the 1940′s, but earlier products had a lot of biases, and since then changes in instrumentation have taken place which may lead to discontinuities in the data, and problems arose especially for upper atmospheric data. Is the atmosphere drying up? June 23, 2008 http://chriscolose.wordpress.com/2008/06/23/is-the-atmosphere-drying-up
    Furthermore in the AR4 WG1 it shows that data is consistent with increasing humidity in the upper troposphere and that relative humidity has shown little change. Please see:
    In the absence of large changes in relative humidity, the observed warming of the troposphere (see Section 3.4.1) implies that the specific humidity in the upper troposphere should have increased. As the upper troposphere moistens, the emission level for T12 increases due to the increasing opacity of water vapour along the satellite line of sight. In contrast, the emission level for the MSU T2 remains constant because it depends primarily on the concentration of oxygen, which does not vary by any appreciable amount. Therefore, if the atmosphere moistens, the brightness temperature difference (T2 − T12) will increase over time due to the divergence of their emission levels (Soden et al., 2005). This radiative signature of upper-tropospheric moistening is evident in the positive trends of T2 − T12 for the period 1982 to 2004 (Figure 3.21). If the specific humidity in the upper troposphere had not increased over this period, the emission level for T12 would have remained unchanged and T2 − T12 would show little trend over this period (dashed line in Figure 3.21). 3.4.2.2 Upper-Tropospheric Water Vapour http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch3s3-4-2-2.html
    The reanalysis is using the very same sondes that have proven problematic in the past with respect to the so-called "missing tropospheric hot spot." So it should come as no surprise that "The Friends of Science" bring up the hot spot only a little further down the page:
    However, the Hadley Centre's real-world plot of radiosonde temperature observations shown below does not show the projected CO2 induced global warming hot-spot at all. The predicted hot-spot is entirely absent from the observational record.
    They would appear to be cherry-picking their unreliable datasets. In contrast others appear to be finding the "hot spot" with little problem. See for example:
    Insofar as the vertical distributions shown in Fig. 3 are very close to moist adiabatic, as for example predicted by GCMs (Fig. 6), this suggests a systematic bias in at least one MSU channel that has not been fully removed by either group. The discrepancy could in principle be explained by a surface temperature trend greater from that at 850 hPa, but this trend would have to be nearly 1.0 C decade −1 , which is far greater than indicated by surface records. Steven C. Sherwood et al. (2008) Robust tropospheric warming revealed by iteratively homogenized radiosonde data, Journal of Climate, vol. 21, issue 20, p. 5336
    ... and:
    We find that tropospheric temperature trends in the tropics are greater than the surface warming and increase with height. Our analysis indicates that the near-zero trend from Spencer and Christy's MSU channel-2 angular scanning retrieval for the tropical low-middle troposphere (T2LT) is inconsistent with tropical tropospheric warming derived from their MSU T2 and T4 data. Qiang Fu and Celeste M. Johanso (26 May 2005) Satellite-derived vertical dependence of tropical tropospheric temperature trends, Geophysical Research Letters, Vol. 32, L10703
    ... but then Friends of Science aren't exactly a science organization, are they? Please see:
    In an August 12, 2006, article The Globe and Mail revealed that the group had received significant funding via anonymous, indirect donations from the oil industry, including a major grant from the Science Education Fund, a donor-directed, flow-through charitable fund at the Calgary Foundation. The donations were funnelled through a University of Calgary trust account research set up and controlled by U of C Professor Barry Cooper. [2] [3] The revelations were based largely on the prior investigations of Desmogblog.com, which had reported on the background of FoS scientific advisors and Cooper's role in FoS funding. SourceWatch: Friends of Science http://www.sourcewatch.org/index.php?title=Friends_of_Science
    Here are some other organizations you might not want to get your science reporting from:
    For those who are interested, here is a list in alphabetical order of 32 organizations involved in both the denial campaign surrounding tobacco and that surrounding Anthropogenic Global Warming. I also researched the organizations to see which would appear to be libertarian, including a source for each. Blowing Smoke: 32 Organizations
    Anyway, to answer your original question, the graphs of trends in global averaged relative humidity at specific altitudes has little to say about whether or not the humidity of saturation increases roughly as an exponential function of temperature. But that didn't seem to be what you were really focused on so I turned to consider what you were concerned with.
  33. Blaming the Pacific Decadal Oscillation
    KR at 10:48 AM, re "Evaporated water carries heat into the upper atmosphere, where condensation releases heat to the cooler air, warming it. The resulting precipitation has less energy, or it would remain vapor." Lets think about this. The evaporated water, now a gas, has become an integral part of the atmosphere, thus the heat it carries then becomes accounted for as part of the total carried by the air, does it not? When the water molecule condenses into a water droplet, ie. ceases to be a gas and hence part of the air, even if it gave up all of it's carried heat, then logically there should be no change to the air. Therefore, any heat energy carried with it will mean a loss of heat energy from, and thus a lower temperature of the air it has ceased to be a part of. Does that make sense?
  34. Blaming the Pacific Decadal Oscillation
    Tom Curtis at 15:17 PM, whilst the IOD alone determines weather patterns across perhaps half of Australia from the north-west to the south-east during it's negative (wet) phase, during it's positive phase it's influence covers about 2/3 of Australia, hence the difficulty in correlating droughts in Australia with El-Nino alone. However, as we have seen recently, the widespread flooding has been due to a -ve IOD coinciding with a La-Nina pattern, the last such unique coincidence being 1975, that period likely the wettest time since first settlement, definitely since official records begin.
  35. Blaming the Pacific Decadal Oscillation
    JohnD @55, as a Queenslander, I can tell you that ENSO absolutely dominates weather patterns in Queensland. They are also significant in NSW, Victoria, and across northern Australia. Weather patterns in WA and across the southern states are also affected by events in the Indian Ocean, with a seasonal component as to which is most dominant in the South.
  36. Blaming the Pacific Decadal Oscillation
    RW1 @47:
    The bottom line, for me at least, is net positive feedback is an extraordinary claim that requires extraordinary proof, especially since solar energy is not amplified to anywhere near such an extent and since net negative feedback is far, far more logical for a system stable enough to support life as the Earth is.
    Given that mean global surface temperatures have fluctuated over a 4 degree range (at least) in the recent past, and that over period in which life has existed on Earth has fluctuated over a 20 degree range (at least), the notion that the climate system is dominated by negative feedbacks has been refuted. Given that the 0.1 w/m^2 variation in total solar forcing has a detectable effect on climate (although difficult to detect), the idea that negative forcings dominate under current circumstances is also shown to be false.
  37. The Climate Show Episode 8: Kevin Trenberth
    @Bern: the scale of the proposed carbon capture plants is indeed immense - each plant is about 30-50% of the size of the source coal (or gas) fired power plants. Then there is the volume of recovered CO2 to consider - think of burying one Lake Michigan every year ! Forget about capturing CO2 directly from the atmosphere: capturing CO2 from flue gas (10-15% by volume) is hard enough - capturing it from the atmosphere at 0.0390 % is completely uneconomic, taking more energy than you get from burning the fossil fuels in the first place. Entropy is against you. Also forget about converting pure CO2 back into C + O2. Also takes more energy than you get from burning it in the first place (again, Entropy, but slightly different).
  38. Roy Spencer’s Great Blunder, Part 1
    Probably the article should also mention something about the previous huge blunder that we have seen from Roy Spencer - the one in which for a long time he also claimed that his data is correct and the thermometers and other people's models are all a giant conspiracy - a story which was only debunked when external reviewers have inspected his data and found serial error in his data analysis - more details here! Re: More details here! Many remarks, but no real scientific critique.
  39. Blaming the Pacific Decadal Oscillation
    Are the graphs of global relative humidity here right? http://www.friendsofscience.org/assets/documents/The_Saturated_Greenhouse_Effect.htm
    Moderator Response: See "Humidity is falling."
  40. Blaming the Pacific Decadal Oscillation
    Timothy Chase said: We know that for every degree Celsius you increase the temperature the humidity of saturation has to increase by 8%. We know that for every 10°C it roughly doubles. And we know that water vapor absorbs radiation, just like carbon dioxide, and are able to satellite image that, too. Water vapor doesn't condense to form clouds unless it exceeds the humidity of saturation -- and the humidity of saturation increases with temperature. By a factor of 2 for every 10°C. --------------------------- How does this correlate with the climate4you humidity graphs? http://www.climate4you.com/GreenhouseGasses.htm
  41. Philippe Chantreau at 14:11 PM on 7 March 2011
    Blaming the Pacific Decadal Oscillation
    "Does the angle of insolation and subsequent distribution not change significantly?" What do you mean by significantly? You use a lot of adverbs. If you were talking with Poptech, he would altogether dismiss you for being "subjective." Of course, that would be another sterile rethorical trick. "The Paleo data also shows previous interglacials, with lower CO2 levels, being warmer than the one were are in now. This is a strong indication that CO2 is not a significant driver of these cycles. If it were, temperatures would be even warmer than previous interglacials - not cooler." That argument would hold only if the current temp was equilibrium. It's not. In any case, that is a different argument than your original one in #61, which was that CO2 was not acting as a positive feedback. Once again, ill defined words such as "strong indication" or "significant driver" push your argument more toward the rethorical. I'm not sure what you mean by driver. If that would be initial cause, it is well accepted that the orbital changes are the driver and that CO2 is a feedback. Your argument in post 61 that the lag shows that CO2 is not a feedback is no more valid now than it was before. Perhaps it was just poorly formulated. Your assertion that CO2 levels and interglacials do not coincide is false, as shown in the graph in your post #67.
  42. Blaming the Pacific Decadal Oscillation
    I wrote in #58: "Plus the amount of incrementally reflected sunlight from clouds. According to Trenberth 2009, the total reflectivity of clouds is about 79 W/m^2, and the total reflectivity of the surface is about 23 W/m^2. Clouds reflect away over 3 times as much incoming solar energy as the surface for a loss of of about 56 W/m^2 for each additional m^2 of cloud cover." Actually, I don't think this is the right way to do this. Clouds cover about 2/3rds of the surface, so 341 W/m^2*0.67 = 228 W/m^2 average incident on the clouds. 79 W/m^2 divided by 228 W/m^2 = 0.34 average reflectivity of clouds. 1/3rd of the surface is cloudless, so 341 W/m^2*0.33 = 113 W/m^2 average incident on the cloudless surface. 23 W/m^2 divided by 113 W/m^2 = 0.20 average reflectivity of the cloudless surface. 0.34-0.20 = 0.14. 341 W/m^2*0.14 = 48 W/m^2 loss for each additional m^2 of cloud cover.
    Moderator Response: [muoncounter] Sounds like its time to go to an Albedo thread. From that thread, you can link back to originating comments here if necessary.
  43. Blaming the Pacific Decadal Oscillation
    Well claiming that is "minor" amplification compared to albedo is pretty close, especially when in fact albedo and GHG component are of same order. Perhaps we should takes this "CO2 lags temperature" if wish to continue to argue that GHGs are unimportant for glacial/interglacial cycle.
  44. Timothy Chase at 13:18 PM on 7 March 2011
    Blaming the Pacific Decadal Oscillation
    Inline to comment 56 the moderator wrote:
    Moderator Response: [muoncounter] Missing link for 'absorption spectra'. [Daniel Bailey] Tim, I took a shot at what you meant to use for your absorption spectra link. If I was wrong, please let me know what the correct link is & I'll update it.
    Actually that particular link was to a copy of the well-known graphic showing downwelling and upwelling radiation at Top Of Atmosphere as well as the absorption due to different greenhouse gases including nitrous oxide: http://climate-guardian.agilityhoster.com/avatar/index.php?inner_page=transmission Not a big deal, though. While I have made a number of my own graphics using web-based tools, mapping to spheres, etc. that particular graphic is from Global Warming Art. Unfortunately it seems to be having trouble today. Something involving the MySql database I believe.
  45. Blaming the Pacific Decadal Oscillation
    scaddenp (RE: 69), "How does a change in DLR due to change in GHG NOT have an effect on surface temperature? I make no claim that it doesn't, but we are getting off topic here. Moderators - any suggestion where this discussion should go?
  46. Blaming the Pacific Decadal Oscillation
    Timothy Chase at 09:34 AM on 6 March, 2011: Thanks for the link to Tamino's mistake. He used the wrong North Atlantic SST dataset [Kaplan] for his comparison to GISS LOTI. http://wattsupwiththat.com/2011/02/03/tisdale-tasks-tamino/ or at my blog if you'd prefer: http://bobtisdale.blogspot.com/2011/02/comments-on-taminos-amo-post_03.html And thanks for the link to DiLorenzo 2010, but I have read it.
    Moderator Response: [Daniel Bailey] If you feel Tamino used the wrong dataset why have you not corrected him? I note, having read the entire post Tim linked to for you, you were absent from the discussion therein. By definition, Kaplan is THE dataset to use for NA SST's.
  47. Blaming the Pacific Decadal Oscillation
    RW1 - all sorts of wonderful explanations work if you dont worry about arithmetic. The problem with the milankovich theory from day one is that variation in solar and insolation alone are insufficient. You need the GHG feedback as well make it work. You also need a means to turn a NH effect into a global effect - which GHG feedbacks manage nicely. As to idea, that previous interglacial temperatures should depend only on CO2 - we ALREADY agree that milankovich forcing drive this and they are different for each interglacial. How about a model run with ALL the forcings and feedbacks included? To say nothing of also ignoring the physics. How does a change in DLR due to change in GHG NOT have an effect on surface temperature? This is an extraordinary claim that I want to see the evidence for from skeptics.
  48. Timothy Chase at 12:51 PM on 7 March 2011
    Blaming the Pacific Decadal Oscillation
    I had written in 56:
    We can't explain the warm interglacials and ice ages without the amplification due to carbon dioxide (which is released by the oceans when they warm like a warming soda losing its fizz but absorbed when the oceans cool), ice sheets (due to their melting and growth) and water vapor feedback.
    RW1 responded in 61:
    Sure we can. The glacial and interglacial periods in between are driven by changes in the Earth's orbit around the Sun, which in turn changes the distribution of the incoming solar energy immensely. This is enough to overcome what appears to be a very strong net negative feedback operating on the system. CO2 lags or follows these cycles - it does not coincide or precede them.
    CO2 lags warming by no more than 1000 years, likely as the deep ocean gives up carbon. And when I stated that carbon dioxide (under these circumstances) is a feedback that implied a lag of sorts. The warming from a glacial to interglacial takes several thousand years. Therefore the carbon dioxide actually coincides with much of the warming. Which is why the curves appear to be almost on top of one-another. Looking at just the warming due to solar insolation you can't explain the saw tooth structure of the temperature and CO2 trendlines. Things warm rapidly, with the warming period appearing to be perhaps 7000 or 8000 years. But the cooling takes perhaps 100,000 years. Orbital forcings can't explain why this asymmetric pattern appears time and time again. But the rapid decay and slow growth of ice sheets as well as the rapid degassing but slow absorption of carbon dioxide by the oceans and ultimately it minearlization can. For the sawtooth structure please see Figure 1 here: CO2 lags temperature - what does it mean? http://www.skepticalscience.com/co2-lags-temperature-intermediate.htm In the review article: C. Lorius (13 Sept 1990) The ice-core record: climate sensitivity and future greenhouse warming, Nature, Vol 347 ... Hansen and coauthors state:
    The orbital forcing is, however, relatively weak when considered on an annual globally averaged basis (the total insolation received by Earth has varied by 0.7 W m-2 over the past 160 kyr). The amplification of this forcing, the observed dominant 100-kyr cycle and the synchronized termination of the main glaciations and their similar amplitude in the Northern and Southern Hemispheres cannot easily be explained despite developments including the nonlinear response to ice sheets to orbital forcing.
    Solar forcing is weak. You can't even explain the extent to which warming to place even when you include the nonlinear response of ice sheets. And you can't explain the synchronicity of the warming of both hemispheres. Both GCM studies and multivariate studies of paleoclimate data suggest that roughly 40% of the warming of the Antarctic from glacial to interglacial was due to the increase in CO2 from 200 to 300 ppmv. (See page 144.) Furthermore, while recognizing that orbital forcing was responsible for the Milankovitch cycles, they predicted that through the analysis of upcoming ice core samples it would be possible to identify the lag time between the initial warming and the rise in carbon dioxide. Please see:
    This objective is part of the GRIP (Greenland Ice Core Project) and GISP II (Greenland Ice Sheet Project) now being conducted in north central Greenland by Eurpopean and American scientists. These dirllings are expected to reach the bedrock (ice thickness is 3.2 km) in 1992 and to cover the last climate cycle and hopefully more. These cores will allow further documentation of the rapid climate changes discussed here. With a snow accumulation higher than at Vostok they should also allow a better determination of the relative timing (phase lag) of climate and greenhouse forcing. pg.145
    But just as importantly there were times when carbon dioxide rose first. The ice cores from Greenland and Antarctica have taken us back the better part of a million years now. During this time temperature always seems to rise first. However, if you look back further in the case of supervolcanoes and their flood basalt eruptions carbon dioxide rose first, then temperature. Examples of where continental and submarine supervolcanoes gave rise to Large Igneous Provinces resulting in mass extinction include: 55 Mya, Paleocene-Eocene Thermal Maximum – North Atlantic Basalts 65 Mya, end-Cretaceous event resulting from a supervolcano that gave rise to the Deccan basalts in India as it collided with Asia at the time of the formation of the Himalayas 183 Mya, Toracian Turnover (a lesser warming and extinction event in the Early Jurassic period) – Karoo Basalts (Africa) 201 Mya, End Triassic Extinction – Central Atlantic Magmatic Province 251 Mya, Permian-Triassic Extinction that resulted from a supervolcano that left behind the Siberian basalts during the breakup of Pangaea. 360-375 Mya, Late Devonian Extinction – Viluy Traps (Eastern Siberia, more tentative according to Rampino below) For a more extensive list, please see: Vincent E. Courtillot and Paul R. Renne (2003) On the ages of flood basalt events, C. R. Geoscience 335, 113–140 For a recent commentary: Michael R. Rampino (April 13, 2010) Mass extinctions of life and catastrophic flood basalt volcanism, PNAS, vol. 107, no. 15, pp. 6555-6556 Here is recent study showing that the eruption of the Central Atlantic Magmatic Province occured simultaneously with the end Triassic Extinction 201 Mya: Jessica H. Whiteside (April 13, 2010) Compound-specific carbon isotopes from Earth's largest flood basalt eruptions directly linked to the end-Triassic mass extinction, PNAS, vol. 107, no. 15, pp 6721-6725 In recent times temperature generally rose first. But if you look further back, in some cases carbon dioxide rose first, then temperature. And those times that carbon dioxide rose first are strongly associated with sudden changes in climate and the resulting major and minor extinction events.
  49. Blaming the Pacific Decadal Oscillation
    Philippe (RE: 65), "I don't see how your short paragraph argues against the CO2 feedback in interglacials. The adverb "immensely" used in reference to the change in insolation distribution is more rethorical than accurate." How do you figure? Does the angle of insolation and subsequent distribution not change significantly? "Nonetheless, the fact that CO2 changes follow the initial deglaciation induced by orbital changes does nothing to indicate CO2 does not or can not act as a positive feedback. Furthermore, the radiative properties of CO2 are such that it is physically impossible for the gas to not act as a positive feedback at some level." Yes, the physics do suggest at least some positive feedback effect is likely, but I think the data strongly suggest it's negligible and the main forces driving the changes are the orbit combined with the ebb and flow of surface ice, especially since temperatures at the end of the interglacials continue to fall significantly even as CO2 remains relatively high. "Paleo data show CO2 levels coinciding with interglacials and following the initial degalciation. It also shows temp increasing to a level that insolation changes alone would not explain. If you want to argue against that, make an argument that is at least logical. The fact that CO2 changes follow the deglaciation by itself is not enough to prevent it from acting as a feedback. The Paleo data also shows previous interglacials, with lower CO2 levels, being warmer than the one were are in now. This is a strong indication that CO2 is not a significant driver of these cycles. If it were, temperatures would be even warmer than previous interglacials - not cooler.
  50. Blaming the Pacific Decadal Oscillation
    #47 RW1 says "The bottom line, for me at least, is net positive feedback is an extraordinary claim that requires extraordinary proof,... " Net positive feedback in climate science is not the same as net positive feedback in most other fields. The terminology in climate science are a bit messed up in that a "net positive" feedback per standard climate science convention would still be a net NEGATIVE feedback as long as the positive feedback is less than the increased blackbody radiation from the increased temperature of the earth. Or to put it another way, the increased blackbody radiation from a warming earth is not included in the feedback sums to determine whether there is postive or negative feedback.

Prev  1864  1865  1866  1867  1868  1869  1870  1871  1872  1873  1874  1875  1876  1877  1878  1879  Next



The Consensus Project Website

THE ESCALATOR

(free to republish)


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