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  2135  2136  2137  2138  2139  2140  2141  2142  2143  2144  2145  2146  2147  2148  2149  2150  Next

Comments 107101 to 107150:

  1. The first global warming skeptic
    (Excuse me for re-using something I have written elsewhere recently.) Even if absorption is saturated, it does not mean that the greenhouse effect is saturated. It is because molecules absorbing radiation are also molecules emitting radiation. As the concentration of absorber molecules increases, shorter geometrical depth of air becomes enough to attain "effectively full" absorption. Then, if we envisage the atmosphere consisting of "fully absorptive layers", the number of such layers increases. So the number of occurrence of absorption and re-emission increases in the pathway from the ground to the top of the atmosphere. The process results in larger difference of temperature between the surface and the height from where the upward emission escapes to outer space, i.e. greater greenhouse effect. Note that "re-emission" here does not mean that excited absorber molecules simply de-excite. Instead, the energy of absorbed radiation is transferred from absorber molecules to surrounding molecules (not usually absorbers), in other words, increases internal energy of air, or raising air temperature there. Then, part of internal energy is transferred to absorber molecules again, and then these molecules emit radiation according to the local temperature and emissivity of air (which is dependent on concentration of absorber molecules etc.). Thus, air cools by emission of radiation. Because internal energy is involved, greenhouse effect cannot be closed within a limited wavelength range. Radiative processes of all wavelength range (and also convective processes when relevant) must be taken into account together. (Therefore, the "fully absorptive layers" approximation is not useful for quantitative evaluation, regrettably.)
  2. How do we know CO2 is causing warming?
    TTTM, this comment on the RealClimate thread (#28, from J.A. Smith) might help you understand this a little better: "As an oceanographer working on air/sea interaction and mixed layer dynamics, I hope I can clarify this issue somewhat (in fact, I’m at sea right now on the R/P FLIP, gathering data to study wave and mixed layer dynamics, but this is off the point). I think a major aspect of the balance has been glossed over: the ocean is heated mainly by the visible part of the spectrum, the energetic part of the sun’s glare. This penetrates several meters (blue-green can penetrate several 10’s of meters, particularly in the clear water found away from coasts). In contrast, the only paths for heat LOSS from the ocean are infrared (blackbody) radiation and latent heat (evaporation). The sun heats the uppermost few meters; this has to find its way to the actual very thin surface layer to be lost. In equilibrium, then, there is a significan flux toward the surface a few cm under, and the sense of flux from infrared alone has to be significantly upward. Given this, it is quite clear that any reduction in the efficiency of upward radiation (by, say, reflecting it right back down again), will have to be compensated for by increasing the air/sea (skin) temperature difference, hence having a warmer subsurface temperature. This still leaves aside the latent heat flux, which in general accounts for something like half the upward heat flux. The balance is NOT, as portrayed here, between up and down infrared; rather it is downward “visible” (including ultraviolet, even), versus upward NET infrared and latent heat fluxes. Once trapped in the mixed layer, any excess heat makes its way down into the interior via much larger scale processes, including lateral advection and mixed-layer deepening due to wind and wave induced motions. This large-scale vertical redistribution takes a while- decades to hundreds of years- before equilibrium is re-established. The fact that we can already see this is quite remarkable."
  3. How do we know CO2 is causing warming?
    @TTTM, the point is that an increase in the temperature of the top of the skin layer will decrease the difference between it and the bottom of the skin layer, which reduces the heat flow from the ocean to the air above. In other words, the oceans will retains more The fact that the impact of CO2 seems small is deceptive, as the forcing is *added* to that of clouds. The small imbalance means that, on average, the oceans are retaining slightly more heat.
  4. How do we know CO2 is causing warming?
    TimTheToolMan at 13:43 PM, try running an anti-virus scan and see if it finds any unwanted cookies.
  5. How do we know CO2 is causing warming?
    @johnd Yes, the experiment has some value to demonstrate the effect but you're right in that its not a definitive answer without understanding all the energies at the surface at the time of increased vs decreased LW radiation. Evaporation has the possibility to actually turn the result on its head and its simply not being measured in that experiment.
  6. How do we know CO2 is causing warming?
    Thanks for the reference Tom. Perhaps you're right about "part two". In part one, however, He doesn't get around to addressing the question until the very last section where he briefly starts on conduction as a mechanism of heat transfer and at that point has totally ignored the fact the ocean has a cold skin so his conduction theory is trying to move energy from a colder place to a warmer one.
  7. How do we know CO2 is causing warming?
    TimTheToolMan at 13:37 PM, I understand what you are seeking in wanting the effect quantified. However I also see the relevance of the clouds being used in this particular experiment to simulate the effects of CO2 is that the clouds could alter the evaporation rate in that the lower loss of heat due to less evaporation could manifest itself as warming of the skin layer.
  8. How do we know CO2 is causing warming?
    Sorry about the wierd posting. For some reason my broweser has refused to refresh until now and suddenly I've got all manner of reples not seen today. I'll go through each as I can.
  9. How do we know CO2 is causing warming?
    The effect is that of changed skin temperature which they have shown. The theory then goes... the result of that change is decreased heat loss from the ocean. It a two step thing. Simplistically, the skin warms and then the ocean heat cant "cross it" as effectively. What is now missing is the magnitude of the reduction of heat loss as a result of that skin heating. I only bring up the comparison between the LW radiation from the clouds vs LW radiation from CO2 to demonstrate that the effect they measured is very much larger than the effect of CO2. In practice this means that LW radiation from clouds changed the skin temperature by 0.2C whereas the effect of CO2 will be very much smaller than that, perhaps around 0.2/33 = 0.01C. Is that enough of a flux change to account for the ocean heating. Why does everyone think I'm trying to differentiate between different heating mechanisms of CO2 and clouds? Its only relevent to the magnitude of the effect.
  10. It's freaking cold!
    14: "6 reports all within the last 5 months " Look here, where all entries are accompanied by references. Of the 60 entries for all time high temperatures, there were 27 records set within this decade. Of the 60 entries for all time lows, only 2 record lows were set within the decade. Score: 27-2. How's your open-mindedness doing these days?
  11. It's freaking cold!
    Re: Tom Loeber (12, 13) By keeping in mind the Comments Policy when posting (especially the part about posting on the appropriate thread), the vast majority of commenters avoid the Deleted Comments bin. The Yooper
  12. It's aerosols
    Is it possible that the IPCC underestimates the growth of aerosol concentrations from developing countries for the coming century? If aerosol growth is underestimated, then their temperature projections might be too high. And could the cooling effect of aerosols be stronger than climate models suggest?
  13. It's freaking cold!
    Oops. Here is that site I mentioned "Impacts & Causes of the Unusual Cold, Snowy & Stormy 2009~2010 Winter" http://sites.google.com/site/whythe2009winterissocold/ Well, look at that I am not banned but ask me, if I am not allowed to correct my mistakes and point out data that question assumptions here, does that demonstrate tolerance or open mindedness on the part of this web sites managers?
    Moderator Response: You tread dangerous ground here. From the Comments Policy:
    No accusations of deception. Any accusations of deception, fraud, dishonesty or corruption will be deleted. This applies to both sides. Stick to the science. You may criticize a person's methods but not their motives."
    I judge this comment in violation of this, but to allow for you to see this and then have a chance to adjust future comments, will allow it to remain for a while.
  14. It's El Niño
    Isn't the El Nino Southern Oscillation showing a long term trend towards stronger and more frequent El Ninos because of global warming? Because I read a myriad of studies suggesting this. But in recent years that trend seems to be dissipating or is too short of a time period to make any meaningful judgements? Is this trend towards stronger and more frequent El Ninos truly manifesting itself or is it just a fluke of nature?
  15. It's freaking cold!
    I notice that LA international airport reported a record cold temperature recently, so did a number of place in San Diego county. Brazil also recorded an historical record cold. I came across 6 reports all within the last 5 months of record cold in a few countries and that does not go into the first half of this year. I don't readily see that mention of 140 year record cold in England. My mention of it is not that it happened but that I had seen it reported. I think this web site is interesting. Seems the data there is well corroborated. Yes, I was banned. Now, lets see if I still am as I hit the Submit button.
  16. It's methane
    Karmanski @6, That graph needs to be updated: [source: http://www.esrl.noaa.gov/gmd/aggi/]
  17. Climate Cherry Pickers: Falling sea levels in 2010
    John/moderator, please delete my posts 90 and 93 as they contain faulty information. Thanks. Sorry for the hassle.
  18. It's methane
    Methane concetrations have stalled int the atmosphere since approximately 1998. Have scientists figured out why? And is melting permafrost contributing enough methane to significantly raise its concentration in the atmosphere yet?
  19. CO2 is not a pollutant
    Another reason CO2 can be considered a pollutant is that it cools the stratosphere(cool stratospheric conditions promote ozone destruction), and delays the recovery of the ozone hole. Is it possible that CO2 could actually worsen the ozone hole?
  20. Climate Cherry Pickers: Falling sea levels in 2010
    OK, I really should not be trying to do this when I am fighting a bug. The reason for me saying that should be obvious from the above data.
  21. It's a 1500 year cycle
    Dr. S Fred Singer should have check his work before spreading it. There is absolutely no empirical evidence that 1,500 year ocean cycle is causing warmining. When was the last time Dr. S Fred Singer published original research in a peer-reviewed journal?
  22. Climate Cherry Pickers: Falling sea levels in 2010
    Albatross #90 That would tend to indicate that a linear fit is better, although I wouldn't mind looking at the residuals to confirm that :) Either way it looks like BP's analysis is bogus. Best bet is to save the graphs as png or gif files and follow the instructions here
  23. Climate Cherry Pickers: Falling sea levels in 2010
    In 90 I should have said that: "For the quadratic fit the slope of the 95% PI envelope increases with time".
  24. Roger A. Wehage at 10:30 AM on 10 October 2010
    Newcomers, Start Here
    Some excellent points above. John Cook summarized another source of the problem here. According to John's post, about three quarters of the news media and three quarters of the general public are not convinced or deny that humans are causing global warming. Since the numbers match so closely, I tend to think that public opinion is heavily influenced by the news media. News is just another part of our entertainment, so we tend to watch the type of news we agree with and enjoy. And if our newscasters are are not convinced or deny that humans are causing global warming, then it is likely that we are not convinced or deny that humans are causing global warming. Another contributor to the problem, at least in the United States, is that We Don't Care about important national and world issues, but only those little things that make us happy and save us money.
  25. Carbon Dioxide - Everyone's Favorite Pollutant
    A person can die from having less than 1% of their body weight in water in the wrong place. A pint of water in the lungs is called drowning.
  26. Climate Cherry Pickers: Falling sea levels in 2010
    KL and BP, It seems to be lost on both of you, but this thread is about Goddard cherry picking and misrepresenting the global SL data. Yet all I see by you are attempts to obfuscate and detract from that. I would like to know for the record, do you condone Goddard misleading people and cherry-picking. Is that acceptable to you? Anyhow, BP has failed to provide some stats on his regression. It is an academic exercise, b/c that polynomial fit is likely not to be valid much beyond the training window.... Also, please tell me that extrapolating that polynomial curve out to 2100 was a poor joke.
  27. Climate Cherry Pickers: Falling sea levels in 2010
    KL #87 It's naive because it doesn't attempt to account for any reasons for the perceived deceleration (e.g. the recent solar minimum), or attempt to ascertain any improvements that a non-linear fit provides compared to a linear fit. Again, if you're going to try to make strong claims about this kind of thing, your eyeball isn't good enough, you've got to use something that's more objective.
  28. How do we know CO2 is causing warming?
    TimTheToolMan at 09:44 AM, the experiment actually shows an effect. What is there to show that that effect is the result of one particular mechanism to the exclusion of all others?
  29. How do we know CO2 is causing warming?
    I agree with you Doug but you're missing the point entirely. You're right in that the experiment only shows the mechanism. It absolutely does. But what we need now is to take that further and show that the mechanism actually works in terms of its ability to heat the ocean at the rate observed. More specifically does the change in heat flux at the skin as a result of Anthropogenic CO2 account for sufficient decrease in ocean heat to account for the observed ocean warming rates? AFAIK, This question cannot be answered by science at the moment.
  30. How do we know CO2 is causing warming?
    TTTM OK, let's try another analogy. You say clouds are a strong influence and CO2 is small, and thát's a problem. Seeing as we're talking about heating, let's look at cooking. We could knock up some soup in a matter of minutes on the top of the stove. Or we chuck everything in a slow cooker, go off for a day's work and come back 8 or 10 hours later, job done. In both cases, the food is cooked and at serving temperature. All the paper tells us is that if you apply heat to the ocean it will warm. Just as an appliance salesperson can tell us that applying heat to food will cook it. You seem to be wanting the salesperson to become a chef telling us all the different methods of cooking various foods.
  31. How do we know CO2 is causing warming?
    TimTheToolMan at 09:07 AM, that effect is very much smaller indeed, the slope of the relationship was determined as being 0.002ºK (W/m2)-1. When such small values are being put forward, then I believe that it is incumbent upon those conducting the study to similarly explore and account for all other processes that occur simultaneously that might contribute similarly small values, or perhaps larger values either positively or negatively to the nett result, one such example being evaporation which I believe would be very relevant to the study under discussion.
  32. How do we know CO2 is causing warming?
    Tim, I suggest you read the Science of Doom post Does Back Radiation Heat the Ocean? Part 1". But it looks like you'll have to wait for Part 2 to get the full answer you're looking for.
  33. It's cooling
    Thanks very much for that, Best regards, Richo.
  34. How do we know CO2 is causing warming?
    "Can anybody else think of a way to explain this to Tim? " I agree with you Doug but you're missing the point entirely. The point is that nobody has investigated whether the change in fux can account for the ocean heat loss observed recently and blamed on CO2. These are the numbers needed to validate AGW theory as far as CO2 heating the oceans goes. The point about cloud LW vs CO2 LW is only to point out that the effect they've measured is as a result of a large effect and the effect of CO2 will be much smaller.
  35. How do we know CO2 is causing warming?
    You know, when everyone agrees on something, and you don't, it's usually the sign you're either a genius or you're wrong - and you're not a genius.
  36. How do we know CO2 is causing warming?
    @TTTM: "You're both missing the point." No, you are missing the point. The article isn't about the amount of warming, but about the regulatory mechanism the skin layer has for IR radiation transfer to the water below it. "If the amount of IR is reduced to 1/33 as is the effect of CO2, then the amount of warming will likely be be similarly reduced." Indeed, but - as we keep telling you - that is not the point of the article. "It is the amount of warming of the skin that directly relates to any decrease in ocean heat loss decrease due to altered heat flux which is their theory." That sentence is nearly incomprehensible. You should try to clarify your own mind before trying to formulate your arguments. "And you haven't even considered the fact that this heat loss hasn't been quantitatively considered and that is the point of the theory." No, the point of the article is to show the mechanisms that allow LW radiation to warm the ocean despite the fact that infrared radiation is stopped by the skin layer. At this point, it's clear you do *not* want to understand. As for me, I will not respond until you answer this simple question: why you say you had no doubt your argument would fail to convince me. Please elaborate.
  37. Newcomers, Start Here
    Rogers devilish advocate @44 said, Maybe global warming did have something to do with Katrina or Lake Mead or Pakistan, but I wasn't there. I chose these examples because it seems to me that they all have potential financial costs for the American economy. (The, perhaps rather fanciful, case for Pakistan is made here, for example) However the idea that doing nothing results in a cost, is not an intuitive idea, and so I too am somewhat pessimistic about wholesale public acceptance of AGW. I think education, such as sites like SkS, can help - if only by a "trickle down" effect. (Personally, I think that some of the "robust" conversations with contrarians on this site, whilst well intentioned, often end up hardening their already entrenched, if illogical, positions and I have tried, unsuccessfully, to think of a better approach). Sadly, I think appeals to the future good (such as the excellent addendum to my previous post by Daniel) do not enthuse the public (especially in a fragile economy); Doug @45 is on stronger ground arguing the national and personal interest. Ultimately, and sadly, I think it will only be a big event (such as summer ice disappearing from the Arctic) that will grab the wider public's attention, and change peoples minds.
  38. Newcomers, Start Here
    Roger, You paint an interesting, albeit gloomy, picture. "Maybe global warming did have something to do with __ or __ or __, but I wasn't there." Does this person believe that the only things that happen are wherever he or she is? Nothing else matters? I wasn't at Pearl Harbor or Normandy or Hiroshima, but I believe they happened. (Rather than continue with the awkward 3rd person, I'll switch to 'you,' realizing that we're still talking about some hypothetical 3rd party). "People shouldn't be associating global warming with occasional high temperatures, rainfall, or droughts." Yeah, they should: If one frames the question slightly differently: "Would an event like the Moscow heat wave have occurred if carbon dioxide levels had remained at pre-industrial levels," the answer, Hansen asserts, is clear: "Almost certainly not." The frequency of extreme warm anomalies increases disproportionately as global temperature rises. "Were global temperature not increasing, the chance of an extreme heat wave such as the one Moscow experienced, though not impossible, would be small," Hansen says. "don't know anything about El Nino and La Nina, but experts say ..." And you believe those experts, as opposed to the experts who say its a more global problem. Wouldn't it be sensible to check out for yourself what these experts are saying? Because if you don't, I wouldn't go out to buy a car if I were you. "I'm a Patriotic American ... the government shouldn't be wasting my money or telling me what to do about something they know nothing about. But ..." And isn't that the crux of the issue? A true patriot would be concerned with something larger than himself. The welfare of the country as a whole, perhaps? Or beyond? See this essay, from a Fox News personality no less, for some examples of the real concerns of a patriot. We're in this mess because we've said 'I only care about what's happening to me' for far too long.
  39. How do we know CO2 is causing warming?
    You're both missing the point. If you look at the graph reposted by Doug you can see an amount of warming of the skin dependent on the amount of IR. It varies between about 0.1C and 0.3C. This is what they measured using 100W of downward LW radiation from clouds. If the amount of IR is reduced to 1/33 as is the effect of CO2, then the amount of warming will likely be be similarly reduced. It is the amount of warming of the skin that directly relates to any decrease in ocean heat loss decrease due to altered heat flux which is their theory. And you haven't even considered the fact that this heat loss hasn't been quantitatively considered and that is the point of the theory.
  40. It's the ocean
    At some point you're going to find it irresistible to use Google Scholar, Karamanski. Going directly to the well is much more efficient than relying on generalists such as myself to function as proxies hauling teaspoons of information. Plus, why trust me when you can eliminate a layer of fallible human nature and go straight to researchers themselves?
  41. It's the ocean
    Are variations in the Atlantic meriodional overturning circulation driven by the imput of fresh water from the Arctic? Keenlyside et al 2008 did not state what the drivers for a weakening of the Atlantic meriodional overturning were, the paper just used historical analogs of certain regions of the North Atlantic and extrapolated current conditions using climate models. Comparing Keenlyside et al 2008 and the article you provided, the mechanism described in Keenlyside's paper seem to be cyclical on multidecal timescales, while the ocean conveyer discussed in the article you provided is changed by an external factor rather than internal variability. Are the Atlantic meridional overturning circulation and the Great Ocean Conveyor interelated?
  42. Eric (skeptic) at 05:43 AM on 10 October 2010
    The value of coherence in science
    Thanks Doug, I appreciate your feedback (no pun intended). Left my internet dongle at work but I downloaded the first paper to read offline. The second timed out so I will try somewhere else later.
  43. Newcomers, Start Here
    There's real value in remembering that folks may have more than one reason for tackling a problem. Here at SkS we have a few followers who're not particularly concerned about global warming but are quite clued in about the parlous state we'll be in when we've burned or otherwise depleted our endowment of liquid and gaseous hydrocarbons. A circumspect patriot looking forward to a prosperous future for America will include imagining means for how that future will be provided with agile transport and other things presently dependent on fossil fuels, particularly the easily portable types.
  44. Roger A. Wehage at 05:20 AM on 10 October 2010
    Newcomers, Start Here
    Well if "global warming" is responsible for a specific autumn weekends weather, why is it not be responsible for Katrina or the Lake Mead drought or floods in Pakistan ? Let me play the devil's advocate for a moment. And please understand that the following scenario does not reflect my attitude toward global warming. Maybe global warming did have something to do with Katrina or Lake Mead or Pakistan, but I wasn't there. People shouldn't be associating global warming with occasional high temperatures, rainfall, or droughts. What about the 11 straight days of record high temperatures in central Illinois back in the middle of July, 1936? Peoria, Illinois had some of its highest temperatures ever recorded, up to 113°F. Temperatures around here haven't exceeded 95°F in years. So did they have global warming 75 years ago too? Yes, parts of the Midwest have had significant rain the past two years, and we've had equally wet seasons before. But we've now had almost no rain the past six weeks, and little is forecast for the coming weeks. Is global warming causing this too? I've seen much worse droughts than what we are heading into now. I don't know anything about El Nino and La Nina, but experts say they are responsible for our changing climate conditions, not global warming. And there's nothing we can do about it. I'm a Patriotic American, and I generally don't go around telling people that the government shouldn't be wasting my money or telling me what to do about something they know nothing about. But I've had enough. Related to global warming, it is likely that for a long time to come, uninformed public attitude will carry much more clout than frantic scientific outcries.
  45. It's the ocean
    Karamanski, surface temperatures of the North Atlantic have a powerful influence on climate adjacent to the North Atlantic. There's a useful article here from Woods Hole providing a general explanation. It's a bit old, but it provides lots of search terms for following things forward.
  46. The first global warming skeptic
    Remember that a 1% increase in mean global temperature would be just under 3 C*, which is about half the difference between an ice age and today. So a 1% change could still be very important to us! (ofc, you need positive feedback to get the 1% reaction, but articles on here go through that pretty well too) *global temperature averages to something like 293 K iirc, so 10% more is 2.93 K = just under 3 C
  47. It's the sun
    @Ken: "I notice that none of ya'll (Ned KR, kdkd) seem to accept my basic point that the area under ALL the forcing curves represents the total energy gained or lost by the Earth system." That's because the graph shows values starting from a relative reference point, and not an absolute level. You've been told this many times, and yet you refuse to hear it. This suggests you are not interested in debating, but instead pushing your point of view without addressing any challenges to it.
  48. Carbon Dioxide - Everyone's Favorite Pollutant
    @RSVP: we already have a word for "too much water", it is called flooding.
  49. Global warming is accelerating the global water cycle
    @fydijkstra, I have responded to your false claim that there has been no warming since 1998 here.
  50. It hasn't warmed since 1998
    This is a response to fydijkstra in another thread, where he claimed there has not been any warming since 1998. fydijkstra, there has been warming since 1998, as this graph demonstrates: Second, 1998 was an exceptionally warm year. Using it as a starting point to determine a trend is cherry-picking at its best (not to mention the fact that the time frame is too short to indicate statistical significance). In spite of this, the graphs still show modest warming. However, look at what happens if we measure trends right before or after 1998: It's clear that starting in 1998 gives an erroneous idea of the actual temperature trends, which is why contrarians like to do so. That is what we call cherry-picking.

Prev  2135  2136  2137  2138  2139  2140  2141  2142  2143  2144  2145  2146  2147  2148  2149  2150  Next


The Consensus Project Website

THE ESCALATOR

(free to republish)


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