JohnB Posted October 27, 2011 Share Posted October 27, 2011 Swansont, it doesn't require any new thermodynamics. For water (clouds) to only be a feedback for temperature requires that water (clouds) only change in response to a change in temperature. This is generally viewed as being atmospheric temperature, BTW. If water (clouds) change in response to any factor other than temperature, they can then become a temperature forcing and not a feedback. This is a major part of the Dessler/Spencer argument. The consensus view is that clouds are only a feedback to temps, Spencer argues, and shows rather well, that they can be both a forcing and a feedback. Link to comment Share on other sites More sharing options...
swansont Posted October 27, 2011 Share Posted October 27, 2011 Swansont, it doesn't require any new thermodynamics. For water (clouds) to only be a feedback for temperature requires that water (clouds) only change in response to a change in temperature. This is generally viewed as being atmospheric temperature, BTW. If water (clouds) change in response to any factor other than temperature, they can then become a temperature forcing and not a feedback. This is a major part of the Dessler/Spencer argument. The consensus view is that clouds are only a feedback to temps, Spencer argues, and shows rather well, that they can be both a forcing and a feedback. Does the water vapor change spontaneously? That would violate thermodynamics. I was under the impression that water vapor and clouds are not the same thing in the models. Clouds are not water vapor, they are water droplets. They will have a different interaction with radiation. Are they talking about enhanced cloud formation decreasing water vapor? Link to comment Share on other sites More sharing options...
questionposter Posted October 27, 2011 Share Posted October 27, 2011 (edited) Right. That's called weather. And it's driven by heat, which raises the temperature — we're looking for something long-term and not driven by temperature, which is in the models, and why this is a feedback term. But that is long term because of that exponential capacity for heat that water vapor has. As more localized low-pressure systems form, more water is in the atmosphere to absorb heat, which in the long run will heat up the atmosphere more, and make it easier for abnormally large amounts of water to be deposited in rain. Edited October 27, 2011 by questionposter Link to comment Share on other sites More sharing options...
swansont Posted October 27, 2011 Share Posted October 27, 2011 But that is long term because of that exponential capacity for heat that water vapor has. As more localized low-pressure systems form, more water is in the atmosphere to absorb heat, which in the long run will heat up the atmosphere more, and make it easier for abnormally large amounts of water to be deposited in rain. Yes. Feedback from heating. It's not long term, though, because a low-pressure system in one place implies a high-pressure system elsewhere unless, again, you can explain why the overall average pressure has changed over time. If you contend the recent temperature increase is caused by water vapor, the question is why did it only just happen? What's your model that explains this with no forcing being present? Link to comment Share on other sites More sharing options...
questionposter Posted October 27, 2011 Share Posted October 27, 2011 (edited) Yes. Feedback from heating. It's not long term, though, because a low-pressure system in one place implies a high-pressure system elsewhere unless, again, you can explain why the overall average pressure has changed over time. If you contend the recent temperature increase is caused by water vapor, the question is why did it only just happen? What's your model that explains this with no forcing being present? Well I don't really want to do a lot of research right now, so all I can do is just infer that because there is heating, more water evaporates into the atmosphere to trap more heat, and since there's more heat, more air is moving which will allow water vapor to enter the atmosphere more easily. Edited October 27, 2011 by questionposter Link to comment Share on other sites More sharing options...
JohnB Posted October 28, 2011 Share Posted October 28, 2011 Does the water vapor change spontaneously? That would violate thermodynamics. I was under the impression that water vapor and clouds are not the same thing in the models. Clouds are not water vapor, they are water droplets. They will have a different interaction with radiation. Are they talking about enhanced cloud formation decreasing water vapor? Ah, gotcha. We were talking about two slightly different things. You were specifically talking about water vapour, I wasn't. Yes, the ability of the atmosphere to support a given quantity of water vapour is dependent on temperature, as you say. I was taking the next step as well. (and this seems to be the logic used in the models) Since the ability of the atmosphere to form clouds is dependent on the amount of WV present, the consensus view is that clouds are also dependent on temperature. It's that step I and others have problems with, not the first one. So we aren't actually in disagreement. Questionposer, the atmosphere is dynamic rather than static, it's not a great idea to attempt to consider one part in isolation. A higher surface temp means that the air can carry more water. Water blocks the IR and increases warming in a seeming neverending cycle. However hot warm air rises and cools to form clouds. Rain is the result of transport of heat to the upper atmosphere, so increased rain is actually proof of an increasing cooling effect. Similarly increased rain means increased clouds. Clouds will act a blocker for outgoing IR from the surface (a warming effect) and at the same time act as a blocker for incoming IR from the Sun (cooling effect), and block visible light that would be converted to IR on the surface (cooling effect). And that's just the very basics. The magnitude of the effects will vary with the density of the cloud as well as the height and also the speed of the Hadley Cells. While each part of the system can be looked at in detail the overall response of the entire system has to be examined for any conclusions to be made. Consequently "all I can do is just infer that because there is heating, more water evaporates into the atmosphere to trap more heat" is only the beginning of the story. Link to comment Share on other sites More sharing options...
questionposter Posted October 28, 2011 Share Posted October 28, 2011 (edited) Questionposer, the atmosphere is dynamic rather than static, it's not a great idea to attempt to consider one part in isolation. A higher surface temp means that the air can carry more water. Water blocks the IR and increases warming in a seeming neverending cycle. However hot warm air rises and cools to form clouds. Rain is the result of transport of heat to the upper atmosphere, so increased rain is actually proof of an increasing cooling effect. Similarly increased rain means increased clouds. Clouds will act a blocker for outgoing IR from the surface (a warming effect) and at the same time act as a blocker for incoming IR from the Sun (cooling effect), and block visible light that would be converted to IR on the surface (cooling effect). And that's just the very basics. The magnitude of the effects will vary with the density of the cloud as well as the height and also the speed of the Hadley Cells. While each part of the system can be looked at in detail the overall response of the entire system has to be examined for any conclusions to be made. Consequently "all I can do is just infer that because there is heating, more water evaporates into the atmosphere to trap more heat" is only the beginning of the story. Even though the water vapor rises into the clouds and cools, the energy that carried it there doesn't disappear, it tries to form an equilibrium with the surrounding air and get's dispersed, so the upper atmosphere is actually slowly heating as well. Clouds can reflect light into space, but they can easily reflect light at an angle onto the surface of the Earth as well and also help to trap heat below them. Edited October 28, 2011 by questionposter Link to comment Share on other sites More sharing options...
swansont Posted October 28, 2011 Share Posted October 28, 2011 Well I don't really want to do a lot of research right now, so all I can do is just infer that because there is heating, more water evaporates into the atmosphere to trap more heat, and since there's more heat, more air is moving which will allow water vapor to enter the atmosphere more easily. Where does the excess heat come from? Link to comment Share on other sites More sharing options...
JohnB Posted October 30, 2011 Share Posted October 30, 2011 Even though the water vapor rises into the clouds and cools, the energy that carried it there doesn't disappear, it tries to form an equilibrium with the surrounding air and get's dispersed, so the upper atmosphere is actually slowly heating as well. Um, no. The WV radiates the heat as it cools and the radiation leaves the system. Radiation upward = Out of the atmosphere. That's one of the reasons why it's a cooling effect. Link to comment Share on other sites More sharing options...
questionposter Posted October 31, 2011 Share Posted October 31, 2011 (edited) Um, no. The WV radiates the heat as it cools and the radiation leaves the system. Radiation upward = Out of the atmosphere. That's one of the reasons why it's a cooling effect. You mean infrared light? Yeah, some infra-red light escapes no matter what thought, but the Earth's atmosphere is thick enough to trap some of it for more than just a few seconds. So I mean, there will always be some cooling, but the atmosphere in general is heating up, there is a greater amount to cool down from as years pass. Where does the excess heat come from? I'm not sure what your referring to. The sun? Water vapor? The sun radiates energy onto Earth, water absorbs heat, water evaporates, water traps more heat and make's air expand, expansion of air makes more room for water to evaporate at an accelerated rate. Edited October 31, 2011 by questionposter Link to comment Share on other sites More sharing options...
kitkat Posted October 31, 2011 Share Posted October 31, 2011 By the time science obtains all of the data of which can only happen by experiencing it through the coming decades, it seems rather unproductive to stress over it now. It is not matter of doing something about it because I do not believe there is anything we could do to reverse it. Another big issue is money since sure you can create jobs but you are not manufacturing for profit, only cleaning up all the damage we have done. Link to comment Share on other sites More sharing options...
swansont Posted October 31, 2011 Share Posted October 31, 2011 I'm not sure what your referring to. The sun? Water vapor? The sun radiates energy onto Earth, water absorbs heat, water evaporates, water traps more heat and make's air expand, expansion of air makes more room for water to evaporate at an accelerated rate. But that process has been going on for a long time. Why haven't we seen these effects before now? Link to comment Share on other sites More sharing options...
Essay Posted October 31, 2011 Share Posted October 31, 2011 By the time science obtains all of the data of which can only happen by experiencing it through the coming decades, it seems rather unproductive to stress over it now. It is not matter of doing something about it because I do not believe there is anything we could do to reverse it. Another big issue is money since sure you can create jobs but you are not manufacturing for profit, only cleaning up all the damage we have done. You think we should wait until GW fully manifests to get the final proof? But each ecosystem component has a different lag time for heating to manifest; and what about ocean acidification? When would you suggest... ummm well, nevermind. Fortunately, your belief doesn't dictate reality. In reality, there is the Wedges Strategy, which can stabilize and even reverse the CO2 problem before its effects are fully manifested in the environment. http://cmi.princeton...edges/intro.php There are now more than 15 wedges ready to go, and we only need to pick 8 or 9 to stabilize CO2. There are many options to mix and match wedges also; and some of these wedges help solve many of the 8 Millennium Development Goals. For profit? What could create more value than restoring ecosystem services? I guess it depends on what generates demand for something. Some of the "wedges" involve new products and new industries and include low, medium, and high-tech solutions. They seems ideally suited for our current situation where old products and old industries are not driving much demand. I googled: Land use wedges and the 8 Millennium Development Goals ...and these came up ==> http://www.un.org/en.../climate_07.pdf & also My link came up, along with... Mitigating Climate Change through Food and Land Use see page 33, first paragraph re: Millennium Dev. Goals #1, #3, and #7. ...and that's just a partial list. I could go into more detail on the economic co-benefits of land-use change (furthering Goals #4 & #5 also) if you're interested. === Not only is the problem solvable, but it seems to be our only opportunity for creating new economic sectors (or reviving old sectors) that can handle the 8 billion (or 1 billion additional) people that will be here in another decade. We need to double food production!! over the next 40 years! Can We Feed the World and Sustain the Planet?"A five-step global plan could double food production by 2050 while greatly reducing environmental damage" By Jonathan A. Foley; October 12, 2011 http://www.scientifi...-feed-the-world "Five solutions, pursued together, can achieve these goals: stop agriculture from consuming more tropical land, boost the productivity of farms that have the lowest yields, raise the efficiency of water and fertilizer use worldwide, reduce per capita meat consumption and reduce waste in food production and distribution. Please help these people by advocating for these types of solutions, which should lead to developing new, sustainable economic sectors. Thanks, ~ ...there will always be some cooling, but the atmosphere in general is heating up, there is a greater amount to cool down from as years pass. That is a very good description!=== JohnB: It might be more accurate to say increased heat loss, rather than a "cooling effect;" but either way, about half of that increased heat loss is re-radiated back down toward the planet's surface. That's why at night it stays warmer than the surface of the moon, though in dry (desert) areas it does get much colder at night than it does in more humid areas (with similar daytime temps). If there is more CO2, then its heating effect will increase water vapor. That extra water vapor then adds even more heating (of the surface) from the atmosphere. ...and it increases the heat loss to space also, to balance the increased heating from CO2. One difference between heating from CO2, and from other sources, is that the heating occurs 24/7/365 over every square foot of the Earth's surface, decade after decade. Other forcers are variable and usually don't persist as is predicted for this injection of CO2. ~ 1 Link to comment Share on other sites More sharing options...
questionposter Posted October 31, 2011 Share Posted October 31, 2011 But that process has been going on for a long time. Why haven't we seen these effects before now? We have been seeing these effects before at least in a core sample, its just that most of the global climate change takes a while to really happen. Plus, it's already even known that mere water vapor is one of the main greenhouse gases. Link to comment Share on other sites More sharing options...
kitkat Posted October 31, 2011 Share Posted October 31, 2011 You think we should wait until GW fully manifests to get the final proof? But each ecosystem component has a different lag time for heating to manifest; and what about ocean acidification? When would you suggest... ummm well, nevermind. Fortunately, your belief doesn't dictate reality. In reality, there is the Wedges Strategy, which can stabilize and even reverse the CO2 problem before its effects are fully manifested in the environment. http://cmi.princeton...edges/intro.php There are now more than 15 wedges ready to go, and we only need to pick 8 or 9 to stabilize CO2. There are many options to mix and match wedges also; and some of these wedges help solve many of the 8 Millennium Development Goals. For profit? What could create more value than restoring ecosystem services? I guess it depends on what generates demand for something. Some of the "wedges" involve new products and new industries and include low, medium, and high-tech solutions. They seems ideally suited for our current situation where old products and old industries are not driving much demand. I googled: Land use wedges and the 8 Millennium Development Goals ...and these came up ==> http://www.un.org/en.../climate_07.pdf & also My link came up, along with... Mitigating Climate Change through Food and Land Use see page 33, first paragraph re: Millennium Dev. Goals #1, #3, and #7. ...and that's just a partial list. I could go into more detail on the economic co-benefits of land-use change (furthering Goals #4 & #5 also) if you're interested. === Not only is the problem solvable, but it seems to be our only opportunity for creating new economic sectors (or reviving old sectors) that can handle the 8 billion (or 1 billion additional) people that will be here in another decade. We need to double food production!! over the next 40 years! Please help these people by advocating for these types of solutions, which should lead to developing new, sustainable economic sectors. Thanks, ~ That is a very good description! === JohnB: It might be more accurate to say increased heat loss, rather than a "cooling effect;" but either way, about half of that increased heat loss is re-radiated back down toward the planet's surface. That's why at night it stays warmer than the surface of the moon, though in dry (desert) areas it does get much colder at night than it does in more humid areas (with similar daytime temps). If there is more CO2, then its heating effect will increase water vapor. That extra water vapor then adds even more heating (of the surface) from the atmosphere. ...and it increases the heat loss to space also, to balance the increased heating from CO2. One difference between heating from CO2, and from other sources, is that the heating occurs 24/7/365 over every square foot of the Earth's surface, decade after decade. Other forcers are variable and usually don't persist as is predicted for this injection of CO2. ~ Okay, but who is responsible for getting these projects in motion? government or science Link to comment Share on other sites More sharing options...
kitkat Posted October 31, 2011 Share Posted October 31, 2011 You think we should wait until GW fully manifests to get the final proof? But each ecosystem component has a different lag time for heating to manifest; and what about ocean acidification? When would you suggest... ummm well, nevermind. Fortunately, your belief doesn't dictate reality. In reality, there is the Wedges Strategy, which can stabilize and even reverse the CO2 problem before its effects are fully manifested in the environment. http://cmi.princeton...edges/intro.php There are now more than 15 wedges ready to go, and we only need to pick 8 or 9 to stabilize CO2. There are many options to mix and match wedges also; and some of these wedges help solve many of the 8 Millennium Development Goals. For profit? What could create more value than restoring ecosystem services? I guess it depends on what generates demand for something. Some of the "wedges" involve new products and new industries and include low, medium, and high-tech solutions. They seems ideally suited for our current situation where old products and old industries are not driving much demand. I googled: Land use wedges and the 8 Millennium Development Goals ...and these came up ==> http://www.un.org/en.../climate_07.pdf & also My link came up, along with... Mitigating Climate Change through Food and Land Use see page 33, first paragraph re: Millennium Dev. Goals #1, #3, and #7. ...and that's just a partial list. I could go into more detail on the economic co-benefits of land-use change (furthering Goals #4 & #5 also) if you're interested. === Not only is the problem solvable, but it seems to be our only opportunity for creating new economic sectors (or reviving old sectors) that can handle the 8 billion (or 1 billion additional) people that will be here in another decade. We need to double food production!! over the next 40 years! Please help these people by advocating for these types of solutions, which should lead to developing new, sustainable economic sectors. Thanks, ~ That is a very good description! === JohnB: It might be more accurate to say increased heat loss, rather than a "cooling effect;" but either way, about half of that increased heat loss is re-radiated back down toward the planet's surface. That's why at night it stays warmer than the surface of the moon, though in dry (desert) areas it does get much colder at night than it does in more humid areas (with similar daytime temps). If there is more CO2, then its heating effect will increase water vapor. That extra water vapor then adds even more heating (of the surface) from the atmosphere. ...and it increases the heat loss to space also, to balance the increased heating from CO2. One difference between heating from CO2, and from other sources, is that the heating occurs 24/7/365 over every square foot of the Earth's surface, decade after decade. Other forcers are variable and usually don't persist as is predicted for this injection of CO2. ~ Okay, but who is responsible for getting these projects in motion? government or science Link to comment Share on other sites More sharing options...
swansont Posted October 31, 2011 Share Posted October 31, 2011 We have been seeing these effects before at least in a core sample, its just that most of the global climate change takes a while to really happen. Citation? You're still on the hook for explaining how it happened quickly this time, and not at other times. Link to comment Share on other sites More sharing options...
JohnB Posted November 1, 2011 Share Posted November 1, 2011 Citation? You're still on the hook for explaining how it happened quickly this time, and not at other times. I'm getting confused. What happened quickly? The rise in temps or the rise in CO2? Link to comment Share on other sites More sharing options...
questionposter Posted November 1, 2011 Share Posted November 1, 2011 (edited) Citation? You're still on the hook for explaining how it happened quickly this time, and not at other times. I thought we agreed that humans, which you yourself stated, started the initial heating to cause a chain reaction of heating. Edited November 1, 2011 by questionposter Link to comment Share on other sites More sharing options...
swansont Posted November 1, 2011 Share Posted November 1, 2011 I thought we agreed that humans, which you yourself stated, started the initial heating to cause a chain reaction of heating. If you agreed to that I missed it. I was under the impression you were arguing that all of the temperature increase can be attributed to water vapor. But a chain reaction doesn't really occur — you would reach a new steady-state. AFAIK that's "baked in" to the models — the CO2 forcing value includes the feedback term. I'm getting confused. What happened quickly? The rise in temps or the rise in CO2? The water-vapor-induced temperature increase, but this appears to be based on some miscommunication. Link to comment Share on other sites More sharing options...
questionposter Posted November 2, 2011 Share Posted November 2, 2011 If you agreed to that I missed it. I was under the impression you were arguing that all of the temperature increase can be attributed to water vapor. But a chain reaction doesn't really occur — you would reach a new steady-state. AFAIK that's "baked in" to the models — the CO2 forcing value includes the feedback term. But what else causes exponential spikes in global temperatures in the past (I can't find core sample stuff online, but I can cite a book published in 2009-10 if you really really don't think I'm telling the truth about the graphs)? Wouldn't CO2 trigger more water in the atmosphere, which would allow the atmoshpere to heat up to the point where the permafrost melts, which allows the atmosphere to hear up enough to nearly completely melt Antarctica, which without it to deflect light allows even more heating? Link to comment Share on other sites More sharing options...
swansont Posted November 2, 2011 Share Posted November 2, 2011 But what else causes exponential spikes in global temperatures in the past (I can't find core sample stuff online, but I can cite a book published in 2009-10 if you really really don't think I'm telling the truth about the graphs)? Wouldn't CO2 trigger more water in the atmosphere, which would allow the atmoshpere to heat up to the point where the permafrost melts, which allows the atmosphere to hear up enough to nearly completely melt Antarctica, which without it to deflect light allows even more heating? Yes, CO2 would trigger more water in the atmosphere — that's what's in the models. The past spikes correlate with eccentricity variation in the earth's orbit — the trigger there is the solar radiation hitting the planet, and in those cases, CO2 was also from a feedback effect. (IOW, CO2 did not cause the initial rise in temperature) http://en.wikipedia.org/wiki/Milankovitch_cycles#Orbital_shape_.28eccentricity.29 That kind of change doesn't happen in a matter of decades, though, and the ice-age-cycle CO2 levels topped out at under 300 ppm. http://en.wikipedia.org/wiki/File:Carbon_Dioxide_400kyr.png Link to comment Share on other sites More sharing options...
questionposter Posted November 2, 2011 Share Posted November 2, 2011 Yes, CO2 would trigger more water in the atmosphere — that's what's in the models. The past spikes correlate with eccentricity variation in the earth's orbit — the trigger there is the solar radiation hitting the planet, and in those cases, CO2 was also from a feedback effect. (IOW, CO2 did not cause the initial rise in temperature) http://en.wikipedia....eccentricity.29 That kind of change doesn't happen in a matter of decades, though, and the ice-age-cycle CO2 levels topped out at under 300 ppm. http://en.wikipedia....xide_400kyr.png Ok, well what about now? Is there a lot of eccentricity in Earth's orbit right now? Because the temperatures are predicted to go up in a similar fashion to those spikes in the past. Link to comment Share on other sites More sharing options...
swansont Posted November 2, 2011 Share Posted November 2, 2011 Ok, well what about now? Is there a lot of eccentricity in Earth's orbit right now? Because the temperatures are predicted to go up in a similar fashion to those spikes in the past. First paragraph of the link I provided The Earth's orbit is an ellipse. The eccentricity is a measure of the departure of this ellipse from circularity. The shape of the Earth's orbit varies in time between nearly circular (low eccentricity of 0.005) and mildly elliptical (high eccentricity of 0.058) with the mean eccentricity of 0.028. The major component of these variations occurs on a period of 413,000 years (eccentricity variation of ±0.012). A number of other terms vary between components 95,000 and 125,000 years (with a beat period 400,000 years), and loosely combine into a 100,000-year cycle (variation of −0.03 to +0.02). The present eccentricity is 0.017. No, the temperature is not predicted to go up like spikes in the past. The temperature is already there, the CO2 levels are higher and the temperature increase is happening much, much faster. http://upload.wikimedia.org/wikipedia/en/6/63/Co2-temperature-plot.svg Link to comment Share on other sites More sharing options...
Essay Posted November 2, 2011 Share Posted November 2, 2011 But what else causes exponential spikes in global temperatures in the past (I can't find core sample stuff online, but I can cite a book published in 2009-10 if you really really don't think I'm telling the truth about the graphs)? Wouldn't CO2 trigger more water in the atmosphere, which would allow the atmoshpere to heat up to the point where the permafrost melts, which allows the atmosphere to hear up enough to nearly completely melt Antarctica, which without it to deflect light allows even more heating? "...atmospheric CO2 is projected to increase to levels that Earth has not experienced for more than 30 million years." Yikes!!! This is from: Understanding Earth's Deep Past: Lessons for Our Climate Future (2011) Board on Earth Sciences and Resources (BESR) Division on Earth and Life Studies (DELS) National Academies Press This fascinating journey into "Deep Time" is worth a look, and it is free! http://www.nap.edu/c...record_id=13111 Authors:Committee on the Importance of Deep-Time Geologic Records for Understanding Climate Change Impacts; National Research Council of the National Academies; BESR, DELS Description: "There is little dispute within the scientific community that humans are changing Earth's climate on a decadal to century time-scale. .... In Understanding Earth's Deep Past, the National Research Council reports that rocks and sediments that are millions of years old hold clues to how the Earth's future climate would respond in an environment with high levels of atmospheric greenhouse gases." "Understanding Earth's Deep Past provides an assessment of both the demonstrated and underdeveloped potential of the deep-time geologic record to inform us about the dynamics of the global climate system. The report describes past climate changes, and discusses potential impacts of high levels of atmospheric greenhouse gases on regional climates, water resources, marine and terrestrial ecosystems, and the cycling of life-sustaining elements." Understanding Earth's Deep Past: Lessons for Our Climate Future (2011) "By the end of this century, without a reduction in emissions, atmospheric CO2 is projected to increase to levels that Earth has not experienced for more than 30 million years." --p.5 QP, this is from the National Academies Press. A change worth 30 million years, occurring within about a century, has not happened for over 50 million years (or longer) of Earth's history. We were just lemurs in the trees, that long ago, and the modern C4 grasses had not even evolved yet. This is also before the polar ice caps existed. This is unprecedented, within the evolutionary histroy of mammallian life. But I'd sure like to get the citation for that 2010 book you mentioned. ~ Link to comment Share on other sites More sharing options...
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