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Michele at 23:07 PM on 30 November 2010The 2nd law of thermodynamics and the greenhouse effect
I think that a physicist doesn't put his own trust in a theory; he has to show it is a true theory. -
damorbel at 22:51 PM on 30 November 20102nd law of thermodynamics contradicts greenhouse theory
Re #204 scaddenp You wrote:- "If you thought greenhouse effect was energy transfer from atmosphere to surface by conduction, then that WOULD be violation of second law." Yes, but no need for emphasis! And:- " However, this is not what is happening as people repeatedly tell you." Tell me? Don't I know it! then you write :- "No incoming radiation, no GHG effect. You cant take the sun out of it." What does that mean? Isn't it the GHGs that are supposed to cause the GH effect? h-j-m has been arguing successfully that the atmosphere is heated directly by GHGs absorbing energy directly from the Sun's radiation, Trenberth's diagram shows it, who is disputing it? The whole planet is heated by the Sun's radiation and very little else, if you have a problem with this could you expand on it? Heat transfer by radiation can only be from a hot body (gas etc.) to a cooler, no different from conduction diffusion or convection. -
HumanityRules at 22:22 PM on 30 November 2010A basic overview of Antarctic ice
For those wishing to understand the uncertainty involved in this sort of work should have a look at this link. It's from an EU funded collaborative effert to constrain GIA estimates. The example they use is quite eye-openning. "For example, a published total mass trend for Antarctica from GRACE is 39±14 km3/yr but with an estimated GIA contribution of 192±79 km3/yr." To me this says GIA uncertainty can be larger than estimates of ice loss. -
quokka at 22:10 PM on 30 November 2010Renewable Baseload Energy
Some good background reading The Case for Baseload - An Engineer's Perspective . -
Argus at 22:04 PM on 30 November 20102009-2010 winter saw record cold spells
JMurphy: "Why do some not seem to see the difference between a cold record which goes back maybe two or three decades (at most, normally - since 1991 in this German case), and warm records that are the warmest or second warmest in records going back 130 years ?" Am I "some"? - I know nothing about Germany in May - it just slipped into a comment because I quoted an article about an all-time low in an Antarctic station. I also, in an earlier comment, quoted recent all-time lows in Wales and N. Ireland for November - coldest "since records began". In Stockholm the weekend offered the coldest temperatures since 1965 (for November), and it is expected (according to today's newspapers) that records from either 1904 (-17) or 1884 (-18) will be beaten this week. But it's all due to NAO-, so I guess it doesn't count at all. -
damorbel at 21:47 PM on 30 November 20102nd law of thermodynamics contradicts greenhouse theory
Re #198 KR The case for warming due to back radiation has not been made. GHGs are distributed more or less uniformly up to 80km except for water, by far the dominant GHG, which drops to a low concentration above 15-20km. The relevant point about GHG emission is that it takes place throughout the atmosphere, it is highest where the gas density is highest and, most important, because the temperature at any given location does not change quickly, to a first approximation, GHGs are absorbing (locally) just as much IR as they emit. They do not collect radiation together somehow 'at the top of the atmosphere' (TOA) and send it down (or up) as in Trenberth's 'Radiation Balance' diagram. If that 'collecting at TOA' according to Trenberth were possible there might be a better case for surface warming but you are still stuck with the problem that the TOA is extremely cold and can only take heat from the surface, not send heat down to the surface. Notice that I wrote 'not send down heat to the surface', not 'not send radiation down to the surface'. Radiation is not heat, heating (or cooling) arises only when there is an imbalance between absorbed and emitted radiation. In the troposphere radiation is emitted and absorbed primarily in a balanced way, with height being the only exception. The importance of this exception means that heat transfer due to radiation goes only in one direction only, out into deep space. There are two reasons for this, the atmospheric temperature falls steadily with height according to the lapse rate (-6.5K/km), the atmospheric density also falls with height. Thus the lapse rate defines the direction of heat tansfer and the density variation also ensures that there is always less radiation 'downwards' rather than 'upwards' for the simple reason that the amount of radiating gas reduces with height due to the drop in density with height. -
JMurphy at 20:51 PM on 30 November 2010Renewable Baseload Energy
RSVP wrote : "Its funny how the economic limitations imposed by fossil fuel seem acceptable, whereas those by renewables are not even possible to discuss." Yes, hilarious, especially after 170 posts of discussion, and counting... -
RSVP at 19:39 PM on 30 November 2010Renewable Baseload Energy
Its funny how the economic limitations imposed by fossil fuel seem acceptable, whereas those by renewables are not even possible to discuss. When gas was being rationed in the seventies, people got up in lines at 4 in the morning... etc. -
quokka at 18:52 PM on 30 November 2010Renewable Baseload Energy
Estimates of external costs of electricity generation by fuel source are given here EU External Costs for Electricity and Transport The nuclear costs in the study I referenced above include cost of waste management/disposal and cost of decommissioning. -
swieder at 18:24 PM on 30 November 2010Renewable Baseload Energy
I think there are many more externalized cost by using fossile energy production then "just" CO2 cost. Since decades, environmental impact by pollution of air, oceans&rivers and other causes high cost attributed to human health care. The cost are buried on each individual as well as on the society/nation (by overcoming environmental damages - see latest popular example in the gulf). All these cost plus subsidies/grants in favor of these energy technologies are not considered in the $/kWh bill you get. My opinion is that even without climate change, the true cost of renewable are competitive. I dont want to picture the cost of fossile energy artifically high to "get" renewable cost-effective - i truly beieve all cost should be considered and in that case they are cost-effective. Energy prices by fossile and nuclear today simply do not reflect the true value of electricity. -
adelady at 17:48 PM on 30 November 2010Renewable Baseload Energy
One cost that gets overlooked is the cost of water. All of the coal powered station that I know of get a very sweet deal on water. If all "burn-stuff" power generators had to pay the real cost for the water they use, the relative costs would be a lot more realistic. (And perhaps the miners should pay, and pay fully, for the water they divert, appropriate or pollute.) For power stations, some kind of weighted average of industrial, agricultural and domestic prices should be used in combination with a valuation of environmental and fisheries benefits foregone. This of course applies equally to nuclear as it does to coal and other more obvious burning. My belief, without having any reports or other backup, is that manufacturers of renewable power equipment pay standard industrial prices for any water they use in their processes. This is yet another invisible subsidy in the comparative costs exercise. Seeing as both the mining and generation processes for fuel based power either exclude water costs entirely or benefit from no, or insufficient, accountability for the water abused, misused or wasted in acquiring and burning the raw materials. -
dana1981 at 17:22 PM on 30 November 2010Renewable Baseload Energy
Eric #158 - they actually check it monthly, but only pay out annually. I used to have a smart meter, but the utility installed a two-way meter which isn't smart when the solar panels went in. I was a bit disappointed by that. Kevin #162 - aside from the fact that several of these renewable baseload technologies are fairly economically competitive already (and their costs are falling), as a couple other comments have noted, you also have to take into account the costs of the climate change which they are preventing (and other air pollution associated with burning fossil fuels). And a good point from swieder #161 on basically creating baseload capacity by diversifying the grid with various renewable sources. -
quokka at 16:57 PM on 30 November 2010Renewable Baseload Energy
KR, No disputing the climate costs of coal and gas. The problem is nobody is really prepared to pay them. Conventional wisdom suggests that nothing much is about to come out of Cancun, and it's probably right. It seems improbable that the US is likely to price carbon any time soon. In this context, it is imperative that low CO2 technologies be as price competitive as possible if anything is to be achieved in practical terms. When it comes to baseload the only technologies that look to be fit for purpose over the next ten years are CCS, solar thermal and nuclear. That's it. Enhanced geothermal sounds great, but there is little realistic prospect of commercial deployment for at least a decade - perhaps quite a bit longer. Barry Brook summaries the findings of a meta-study of the costs of viable base-load technologies here The arithmetic adds up to nuclear The peer reviewed paper is paywalled, but you can get a PDF by emailing Barry. No doubt there will be a mix of generating technologies which is fine, but anti-nuclear greens are going to have to change their position or there will be no chance whatsoever of averting dangerous climate change. Perhaps I might rephrase that as anti nuclear greens will find themselves marginalized sometime over the next decade if, as is most likely, renewables prove to be too expensive. It is interesting to consider this news Mumbai: The world's largest nuclear park has got the go ahead and the quote from the Indian Environment minister: "India has a population of 1.2 billion. It is the height of foolish romance that India can meet its energy needs from solar and bioenergy". Also consider that this will be nearly 10GWe capacity and occupying 990 hectares. To do something similar with solar thermal you would be looking at something like 1000 sq kms. Energy density counts. -
Rob Painting at 16:57 PM on 30 November 2010A basic overview of Antarctic ice
Agnostic @ 43 - The article deals with a complex issue in an over-simplified way There is only so much information one can put in a "basic" rebuttal before it ceases being a basic rebuttal. Considering the target audience are newcomers to climate science, a pretty good introduction IMO. -
Albatross at 16:47 PM on 30 November 2010A basic overview of Antarctic ice
Reluctant skeptic @47, "...Antarctic sea ice is increasing and we can find ways to explain it away, but was that what the models predicted prospectively?" I'm not sure I understand the question, maybe it was rhetorical. Model runs by Manabe et al. (1992) did in fact predict that there would be very little change in the Antarctic sea ice, at least initially. I do not know why the other question that Daniel addressed even warrants answering. The robustness of the Antarctic sea ice in the face of warming is not indefinite. How the Antarctic responds to further warming also depends, in part on the recovery of Antarctic ozone. So lots of uncertainty there-- I do not believe that scientists are finding ways to "explain it away". Turner and Overland (2009) provide an excellent overview of the complexities of Antarctic sea ice. This SCAR report by Turner et al. (2009) is also highly recommended. But we do know this, in those areas where the sea ice or ice shelves buttressing the glaciers has been lost, the glaciers have accelerated (e.g., Larsen B ice shelf). We also know that as sea levels rise grounding lines will move farther inland, making ice sheets and glaciers more unstable(e.g., recent events under the Pine Island glacier), especially as the oceans continue to warm. The sea ice surrounding Antarctica is important for regulating the rate of loss of ice from the WAIS and EAIS, but it is not the only player. For example, but warming oceans are also playing a role on destabilizing glaciers and ice sheets. My suggestion is to focus on these factors rather than entertaining thoughts about the onset in coming decades of decline in Antarctic sea ice might mean in terms of the theory of AGW. I also happened to notice that the Larsen C has been exposed to open water (i.e., wave action etc.) for several weeks now... -
StyleDoggie at 15:59 PM on 30 November 2010There is no consensus
#274 - Claims of settled science and scientific consensus have been around since at least 1989 - here's a reference from the NYTimes. But NOW, there REALLY IS a consensus. I see. http://query.nytimes.com/gst/fullpage.html?res=950DEED61E3CF937A25750C0A96F948260Moderator Response: Please refrain from using all caps. Use italics or, if really necessary, bold. -
Daniel Bailey at 15:45 PM on 30 November 2010A basic overview of Antarctic ice
Re: reluctant skeptic (47)"The question I need answered is, 'If Antarctic sea ice was decreasing, would that be evidence against global warming?' "
What if it was? Do you really think it would matter? There has been amassed nearly two centuries of studies and evidence, along with the same physics that underlie refrigerators, microwave ovens, the internet, televisions, automobiles, heat pumps, convection ovens, pharmaceutical products, textiles, etc, that all makes climate science the robust discipline it is. This is not to say that uncertainty does not exist; existing uncertainties lie more in the area of rates of change and to a lesser extent, cloud effects (but that window is closing fast). So let's say Antarctic sea ice is decreasing and that it is evidence against global warming. It would be the equivalent of finding 2 identical snowflakes in a single snowstorm: an oddity, but certainly not something sufficient to say that there was no snow... To maintain that it actually could undermine AGW, by itself, would be the equivalent of saying that all of the technology I cited earlier runs on pixie dust, not on fundamental underlying physical principles. Would you believe that? The Yooper -
Daniel Bailey at 15:33 PM on 30 November 2010A visual depiction of how much ice Greenland is losing
Re: muoncounter (86) Thanks, I guess, for the Elliott study. Been a bad week for climate news (lotsa news, all bad [prognosis: grim])."Emissions driven by upcoming seafloor temperature rise, however, may be unprecedented in scale."
Unprecedented? Nay, not unprecedented."Multibeam swath bathymetry data from the southwest margin of the Chatham Rise, New Zealand, show gas release features over a region of at least 20,000 km2. Gas escape features, interpreted to be caused by gas hydrate dissociation, include an estimated a) 10 features, 8–11 km in diameter and b) 1,000 features, 1–5 km in diameter, both at 800–1,100 m water depth. An estimated 10,000 features, ∼150 m in diameter, are observed at 500–700 m water depth. If the methane from a single event at one 8–11 km scale pockmark reached the atmosphere, it would be equivalent to ∼3% of the current annual global methane released from natural sources into the atmosphere. If similar features formed globally, then the cumulative release may have significantly increased the global methane supply into the ocean and atmosphere at the peak of glaciations and potentially contributed to the rapid transition to warmer post‐glacial conditions (e.g. clathrate‐gun hypothesis [Kennett et al., 2003])."
Aah, the wonders of Labatt's Blue. Palate has since shifted to first Blue Moon now to Oberon (all hail)... Between my science instructors and my history instructors (Oktoberfest was indeed a month-long affair to remember), it's a wonder that: 1. I learned anything 2. I still have a liver left Hmm, this topic brings to mind the scene in On The Beach (Gregory Peck 1959 version), where Fred Astaire says this line:“We’re all doomed, you know. The whole, silly, drunken, pathetic lot of us. Doomed by the air we’re about to breathe.”
Of course, he was talking about radiation then, while'st we discuss the maudlin details of CO2 and CH4... How fitting that a movie line from over 50 years ago should serve as a lasting memorial for our race, should we not act on what we now know? The Yooper -
Renewable Baseload Energy
Kevin - When considering costs we should include the cost of continuing CO2 increases. Coal with CCS is pretty unproven, and there's considerable reason to believe that there are risks of sequestered CO2 getting out of the subterranean storage. Natural gas is still a CO2 producer. Nuclear can help, but there are considerable risks and political issues. Renewables can supply baseline power, and reduce the societal cost of continuing temperature increases. Coal and natural gas get really expensive when you factor in climate change. -
Kevin3581 at 14:50 PM on 30 November 2010Renewable Baseload Energy
The point of this post, that renewables can provide base load energy, is true. However, it is NOT accurate to claim that renewables can provide economically competitive base load energy. There have been any number of studies done by MIT, EPRI and even the modeling done by EPA, which look at the technology pathways by which the electric sector would decarbonize with a CO2 price. Yes, there is a lot of renewables build. Yes, there is a lot of energy efficiency. But there is also a lot of nuclear and coal with CCS and natural gas. The models line up the techs from least cost to highest costs -- there is a supply curve for each. They then select the least cost option until it runs into the higher part of the supply curve, then goes to the next most costly and so on. It is misleading to simply say "renewables can supply all the energy we need" w/out including the caveat "but it will cost a lot more than if we were to allow other low CO2 emitting techs to deploy." -
curiouspa at 14:47 PM on 30 November 2010A basic overview of Antarctic ice
I am not nearly as sophisticated in my knowledge of glaciers and climate as most of the other posters but have a decent basic science background. The question I need answered is, " If Antarctic sea ice was decreasing, would that be evidence against global warming? " Antarctic sea ice is increasing and we can find ways to explain it away, but was that what the models predicted prospectively? -
muoncounter at 14:29 PM on 30 November 2010A visual depiction of how much ice Greenland is losing
#85: "the volume of Lake Erie (not that anyone would want to picture that raining down on them)" If methane keeps bubbling up as Arctic temperatures rise, it might start to look and smell like Lake Erie. Elliott 2010: Massive quantities of the greenhouse gas methane are stored beneath the Arctic continental shelf as clathrate hydrates, and the global warming signal is now reaching them. Over contemporary natural seeps, microbial activity tends to oxidize the molecule rapidly. Emissions driven by upcoming seafloor temperature rise, however, may be unprecedented in scale. Flux zones of dimension tens of kilometers are already under observation. Undersea landslides many times this size have been associated with catastrophic hydrate decomposition in the past. Yooper: My geology instruction centered around juggling rockhammers and consuming significant quantities of Labatt's Blue. Twenty-five years in the awl bidness later, I still can't juggle. -
Daniel Bailey at 13:20 PM on 30 November 2010A visual depiction of how much ice Greenland is losing
Re: adelady (83) "Lake Superiors" (outside my window as I type this) is a really useful comparative metric. I had once heard that the volume of water added to the atmosphere due to GW (4% increase) was equivalent to the volume of Lake Superior. When I did the math, I found that Lake Superior by itself roughly equaled the mass of the water in the entire atmospheric column. Wasn't a wasted exercise, though. I did find that the increase in water in the air was equivalent to the volume of Lake Erie (not that anyone would want to picture that raining down on them). If someone runs the numbers to get an ice volume equivalent for Lake Superior, I'd be interested in finding it out. The Yooper -
adelady at 13:05 PM on 30 November 2010A visual depiction of how much ice Greenland is losing
@80 argus Your expectations may be a bit unrealistic. My naive expectation would be that the best we could expect would be a reduction at much the same rate as the increase. But have a look at Tom Wigley's version for zero emissions by 2050. http://bravenewclimate.com/2010/11/24/effect-zero-co2-2050/ -
adelady at 12:59 PM on 30 November 2010A visual depiction of how much ice Greenland is losing
@82 paulm % doesn't really do the job for the Antarctic at least. Most people have real difficulty with big numbers so you need to make it really really plain. 1% of Samoa is _not_ relevant in any meaningful way to 1% of China. Antarctica is the home of the unbelievably big number. If you wanted to use %s you'd be much better off comparing Antarctica ice losses to more familiar "units" like how many/much Sydney Harbours or Lake Superiors. -
Daniel Bailey at 12:38 PM on 30 November 2010There is no consensus
Re: muoncounter (273)"Yooper, I also have some earth sci degrees somewhere in my distant and checkered past. Knew there was something I liked about you."
Early 80's, Central Michigan University. Diploma can be found somewhere in the paleo record. :) Appreciate the sentiments; likewise. Based on many of your comments, you received a better grounding in energy budgets than I did. My instructors taught me other things, like shotgunning whiskey into (many) beers... The Yooper -
Daniel Bailey at 12:27 PM on 30 November 2010There is no consensus
Re: StyleDoggie BTW, consensus is an ever-evolving narrative, adapting (one way or the other) to emerging understanding over time. Much has become known since 2008. That makes the study you cited dated. As my one lone example showed (had you read the link). The Yooper -
mspelto at 11:12 AM on 30 November 2010A basic overview of Antarctic ice
An ice shelf is by definition largely afloat. Large ice shelves are stabilized by pinning points where the ice shelf is supported, see Fleming Glacier. These can be along the margins of the ice shelf such as against an island or underneath the ice leading to an ice rise. As an ice shelf thins through basal melting or increased flow, it is less buttressed by either, which can lead to enhanced rifting, calving and flow rates. Each glacier is different but clearly ice melt as Robert points out is not the main issue even on the Antarctic Peninsula. Take a look at the footage from NASA's operation ice bridge . Take a look at Pine Island Glacier -
JMurphy at 10:54 AM on 30 November 2010It's not bad
Response to Argus taken to 2009-2010 winter saw record cold spells -
JMurphy at 10:52 AM on 30 November 20102009-2010 winter saw record cold spells
(From Positives & Negatives of Global Warming) Argus wrote, quoting from WEEKLYSTANDARD.COM : "In the middle of the month, the German Weather Service quietly acknowledged that the country was experiencing record cold: some 3-5 degrees Celsius below the long-term averages." "Quietly acknowledged", as in notified by press release by the German Met Office : Germany weather in May 2010 - Very cool, very wet, and how rarely the sun shone. Deutscher Wetterdienst Meanwhile, the rest of the highlights for May show why the odd low temperature was of less interest : The combined global land and ocean average surface temperature for May 2010...the warmest such value on record since 1880. For March–May 2010, the combined global land and ocean surface temperature was...the warmest March-May on record. The combined global land and ocean average surface temperature for January–May 2010 was the warmest on record. The worldwide ocean surface temperature for May 2010 was the second warmest May on record... The seasonal (March–May 2010) worldwide ocean surface temperature was the second warmest such period on record... The global land surface temperatures for May and the March–May period were the warmest on record... In the Northern Hemisphere, both the May 2010 average temperature for land areas, and the hemisphere as a whole (land and ocean surface combined), represented the warmest May on record. The Northern Hemisphere ocean temperature was the second warmest May on record. The average combined land and ocean surface temperature for the Northern Hemisphere was also record warmest for the March–May period. State of the Climate Global Analysis May 2010 Why do some not seem to see the difference between a cold record which goes back maybe two or three decades (at most, normally - since 1991 in this German case), and warm records that are the warmest or second warmest in records going back 130 years ? -
muoncounter at 10:51 AM on 30 November 2010It's not bad
#85: "It depends on what you want to see. " Here is a rather objective way to portray this question of hot vs. cold.The high temp anomalies (marked at right) appear in more recent years. I've been playing with this type of display for GISSTemp data; its quite revealing. There's no dependence on wanting to see one thing or the other; its there in plain sight.
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Albatross at 10:44 AM on 30 November 2010It's not bad
Hi Riccardo, Yes-- Joe Romm at CP has been featuring some of the results. Hopefully some of the papers will be discussed here at SS. They are pretty sobering papers in the special issue, and telling that they are now looking at a warming of +4 C or higher by 2100 and focusing on some of the high-end emission scenarios as BAU continues. It looks like AR5 is not going to make for "fun" reading.... PS: John Cook, sorry for wandering off topic. -
muoncounter at 10:40 AM on 30 November 20102nd law of thermodynamics contradicts greenhouse theory
#199: "Convection is a bit special because it won't work 'downwards'" Oh, dear. I guess plate tectonics, thermohaline ocean circulation and onshore/offshore breezes, among other things all just stopped because damorbel says 'it won't work downwards'. -
Riccardo at 10:17 AM on 30 November 2010It's not bad
A special issue of the Philosofical Transactions of the Royal Society may be of interest. It's free through Tuesday 30. -
Albatross at 10:04 AM on 30 November 2010It's not bad
Argus @85, You, it seems, do not wish to "see" the warming, and to that end latch onto every cold record to convince yourself that the warming is not occurring. Doing so is cherry-picking. The data and the scientists are not lying or deceiving you, nor are the scientists cherry-picking, they are looking at all the data. This is what Dr. Meehl had to say: “Despite the increasing number of record highs, there will still be occasional periods of record cold, Meehl notes. "One of the messages of this study is that you still get cold days," Meehl says. "Winter still comes. Even in a much warmer climate, we're setting record low minimum temperatures on a few days each year. But the odds are shifting so there's a much better chance of daily record highs instead of lows." Now that is the truth. You can choose to ignore it or distort it, but doing so does not change the facts nor the truth. And the cold weather currently affecting parts of Europe, is very much in the news.Moderator Response: Argus and everybody else, please put further comments about cooling on a more appropriate thread--even if you are responding to a comment on this thread. -
Paul Barry at 09:52 AM on 30 November 2010A basic overview of Antarctic ice
Thanks for the responses to my question above (Albatross must wonder how someone could be confused by an article that already "deals with an issue in an over-simplified way"!!!). If this article is ever revisited, I think that there are 3 issues than ought to be teased out more clearly in its exposition: (a)the business of quantifying changes to land and sea-ice at the poles - i.e. what's happening; (b) explaining the causes of these changes (especially the differences between changes in Antarctica and the Arctic) in terms of warming/ozone etc.; (c) quantifying impacts (or feedbacks) of these changes especially in terms of albedo-loss to the planet. Another question comes to mind now: Is there a graph anywhere showing theoretical albedo changes for the Arctic, the Antarctic, the Earth generally over the past few decades (to match ice-extent in the graphs of Muoncounter and SRJ above)? Such a graph would be a very useful illustration of issue (c) which, to me, makes that other issue (about whether SH ice-extent increase is statistically significant or not), appear rather minor. -
scaddenp at 09:13 AM on 30 November 20102nd law of thermodynamics contradicts greenhouse theory
Sigh. If you thought greenhouse effect was energy transfer from atmosphere to surface by conduction, then that WOULD be violation of second law. However, this is not what is happening as people repeatedly tell you. No incoming radiation, no GHG effect. You cant take the sun out of it. If you are determined not to learn physics, then we are wasting our time trying to teach you. -
DSL at 09:12 AM on 30 November 20102nd law of thermodynamics contradicts greenhouse theory
Damorbel wrote: "The balls will slowly approach a temperature dependent only on the distance of and the power emitted by your UV source." As I understand it: If the source is a star, and both balls are receiving UV energy, then yes--even though the balls will still exchange radiation at equilibrium. However, that's not what I said. The second ball is not receiving UV radiation. It has been given one time heat by some unknown source. It is cooler than the first ball. My argument is that such a ball is an energy source for the first ball, in addition to the UV source, and it will continue to be an energy source because it receives radiation from the first ball. In this analogy, the second ball is the atmosphere. It receives radiation from the surface, and even though it is cooler than the surface, it radiates some of that energy back toward the surface. Eventually, some of the "backradiation" is absorbed by the surface and turned into work, but most of it gets hung up dancing from molecule to molecule in the troposphere, where convection and conduction also bring it into contact with the surface or bring it to the stratosphere. The point, though, is that the upper troposphere can indeed act as an energy source for the surface and for the lower troposphere (where surface temps are measured), even though the upper troposphere is concurrently cooler. GHGs basically redirect certain frequencies of longwave radiation. The more GHGs, the more LWR is redirected, and the more time LWR stays within the system (heating, doing work, being a nuisance, etc.). -
Argus at 09:09 AM on 30 November 2010It's not bad
Albatross (#79) and Daniel Bailey (#80), I like the wording in the article: "When, however, actual temperature readings reveal record cold, this apparently is not news. " The cherry-picking goes for hot temperatures as well as cold. It depends on what you want to see. -
damorbel at 09:03 AM on 30 November 20102nd law of thermodynamics contradicts greenhouse theory
Re #196 scaddenp you wrote :- "continuing to talk about what happens and how the 2nd law works in conductive energy transfer is not helping you understand how it works in radiative energy transfer." Energy transfer by photons is amazingly similar to that in gases, both exchange momentum in collision processes; in gases it is by inelastic collisions and with photons it is by elastic collision. -
muoncounter at 08:56 AM on 30 November 20102nd law of thermodynamics contradicts greenhouse theory
#197: "you'd be in a warm bath of air at 14C, 1/2 surrounded by radiation from the ground at 14C; 1/2 from deep space at 2.7K." Damorbel, did you just say that radiation from space at 2.7K contributes 50% to keeping that 'warm bath of air' at 14C? What would Clausius say to that? -
damorbel at 08:56 AM on 30 November 20102nd law of thermodynamics contradicts greenhouse theory
Re #192 CBDunkerson you wrote :- "Warmer objects can indeed absorb radiation from cooler objectsYet you insist that this re-emitted radiation can't possibly warm the planet." If it is cooler than the planet, yes. Then you wrote :- "So... what exactly do you think happens to it? It somehow 'knows' the relative temperatures of the matter it was emitted from and the matter it is about to impact and 'changes course' to avoid any matter which is warmer than the previous?" In #200 I wrote:- "Look at it this way. Emitted power is proportional to T^4, thus the warmer object emits most power. Both objects absorb power indpendent of temperature thus the warm object cools down and the cool one warms up, they are in thermal contact as if they were touching each other if the two objects are isolated they will slowly arrive at the same temperature, somewhere between the two original temperatures." Which explains why the cold troposphere cannot raise the temperature of the Earth's surface. You wrote :- "How do you imagine microwave ovens work?" Read #189 3rd para. Microwaves are not 'thermal' like a grill; they have a magnetron inside wich makes single frequency (monochromatic) radiofrequency (RF) power at about 2450MHz, this power is absorbed by water molecules which get hot in consequence. This is quite different from a 'thermal' oven which uses thermal radiation to grill and hot air to bake. In #193 you wrote: "it should be pointed out that 0K has never been observed. It's a theoretical minimum. Nothing that cold is actually known to exist. Therefor your contrast between one thing which 'only' happens above 0K and another which happens regardless of temperature is really two things which happen regardless of temperature." Oh alright then, not 0K, lets put 0.00000000001K. -
muoncounter at 08:51 AM on 30 November 2010There is no consensus
#270: "if you're going to use consensus as argument" The consensus in question in this article is "demonstrated by the number of scientists who have stopped arguing about what is causing climate change – and that’s nearly all of them." Thus there is general agreement among serious scientists that global warming is happening and we are causing it. "you have to have consensus on the important part of the issue - what to do about it" That's a separate question and wildly off-topic. The Hansen op-ed you linked in #270 calls for stronger measures than cap and trade: "There is a better alternative, one that would be more efficient and less costly than cap and trade: 'fee and dividend.'" However, in the US, conservative talking heads have basically killed any hope for any action with their 'cap and tax' hot air. Don't conflate lack of consensus on what to do, which is mired in political rhetoric, to consensus over what is happening. If you want to continue discussing what to do, go to Solving global warming. "the consensus breaks down the more you dig into it." No, it does not. First of all, the survey is older than the Hansen article, so 'the more you dig into it' doesn't make sense. But more importantly: Based on current trends, 41% of scientists believe global climate change will pose a very great danger to the earth in the next 50 to 100 years, compared to 13% who see relatively little danger. Another 44% rate climate change as moderately dangerous. That's 85% in the moderate to very great danger camp. Makes you think that the folks shouting down any ideas for change are the ones causing the problem. Which side are you on? Yooper, I also have some earth sci degrees somewhere in my distant and checkered past. Knew there was something I liked about you. -
swieder at 08:46 AM on 30 November 2010Renewable Baseload Energy
This might be interesting for those who have not heard about this project on the topic of baseload energy with renewables Control of Virtual Power Plants with 100 % Renewable Energy Sources background paper unfortunately just a summary and a citation to corresponding procedings. Rohrig got the "german climate protection award" 2009 - not that this means anything, just to indicate that he is not a nobody in this topic. This is the (german) project site and some english descriptions. The basic finding is that by virtually combining 36 existing wind, solar, biomass and hydropower installations spread throughout Germany, you get a baseload-viable powerplant. It is just as reliable and powerful as a conventional large-scale power station. -
Daniel Bailey at 08:30 AM on 30 November 2010There is no consensus
Re: StyleDoggie Interesting position to take. If you're positing that... 1. It's the total bolus of carbon slug injected into the Earth's atmosphere that matters and 2. Human nature means the cessation of burning of fossil fuels will happen when cold, dead hands are pried off the pumps ...then I'm of a similar mind. I've always liked Hansen's position on fee & dividends, but I suspect it too doesn't go far enough to forestall CO2 emissions quickly enough. Your STATS survey of climate scientists is a bit dated now. In light of current events, most on the fence will be re-thinking just how uncomfortable that position has become. But what the heck do I know? Not a climate scientist. Just some guy on a blog with degrees in the Earth Sciences... The Yooper -
damorbel at 08:27 AM on 30 November 20102nd law of thermodynamics contradicts greenhouse theory
Re #191 DSL you wrote :- "Warmer objects can indeed absorb radiation from cooler objects." Look at it this way. Emitted power is proportional to T^4, thus the warmer object emits most power. Both objects absorb power indpendent of temperature thus the warm object cools down and the cool one warms up, they are in thermal contact as if they were touching each other if the two objects are isolated they will slowly arrive at the same temperature, somewhere between the two original temperatures. Further you wrote:- "If you shine a steady UV light... ... once again reaches an "equilibrium" temp." Let us assume these balls are planets and the UV source is a star. Wavelength is unimportant. The balls will slowly approach a temperature dependent only on the distance of and the power emitted by your UV source. The temperature they reach is not dependent on how shiny they are, that only affects the rate they approach this 'equlibrium' temperature You wrote:- "Your snowman example is not good, because A) you're working primarily with conduction and convection and B) the naked person has an internal engine. There is still radiative transfer, though, between the snowman and the naked person." Temperature rules in all thermal tranfers, be it conduction radiation or convection. Convection is a bit special because it won't work 'downwards' but both radiation and conduction will tend to equalise the temperature in an isolated convective (e.g. gravitational) system. Radiative transfer is not influenced by gravity. -
2nd law of thermodynamics contradicts greenhouse theory
damorbel - And once more, you miss the point in several respects. You've been pointed to Trenberth 2009 several times. Convection and evaporation together represent only 1/4 the energy involved in IR from the ground. The backradiation at 333 W/m^2 is twice the energy of incoming sunlight. The greenhouse effect does not heat the Earth; it slows cooling, by providing a warmer background than outer space, reducing the ability of Earth to dump the energy from incoming sunlight. This is basic radiative energy balance - the Earth radiates to space with P = e*s*A*T^4, and when greenhouse gases decrease emissivity 'e', as per The greenhouse effect and the 2nd law of thermodynamics (intermediate), with an emission spectra like this:Notches in graph A show greenhouse gas bands, where IR is sent back to the ground, as seen in graph B then there is an energy imbalance (more coming in than going out), and the temperature will rise until 'P', the energy radiated to space, equals the sunlight coming in. At this point, damorbel, I'm coming to the conclusion that you are deliberately misunderstanding the point. You've ignored repeated pointers to the physics involved, and brought up multiple straw-man arguments. I don't believe it's worth debating with you unless you are willing to engage in an actual discussion of the science.
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StyleDoggie at 08:11 AM on 30 November 2010There is no consensus
#268 - Here's another reference for you - the consensus breaks down the more you dig into it. http://stats.org/stories/2008/global_warming_survey_apr23_08.html -
StyleDoggie at 08:00 AM on 30 November 2010There is no consensus
Muoncounter #269 - what did you wake up on the wrong side of the bed today? You know any climate scientist that thinks Kyoto or Cap and Trade will stop global warming? My point is that if you're going to use consensus as argument, than you have to have consensus on the important part of the issue - what to do about it, not that it's happening. Here's a reference for you - James Hanson and Cap and Trade. http://www.nytimes.com/2009/12/07/opinion/07hansen.html -
damorbel at 07:53 AM on 30 November 20102nd law of thermodynamics contradicts greenhouse theory
Re #187 KR you wrote :- "IR at greenhouse frequencies gets absorbed and re-emitted within about 100 meters. That means the surface is facing an atmospheric IR emitter at 14C, not -50C. The -50C is reached through atmospheric lapse rate temperature drop, until the altitude where lowering pressure reduces IR absorption enough to radiate to space" To a considerable extent you are correct. On Earth the density of atmospheric GHGs is very low and low level absorption of IR is a very small % of the thermal input to the atmosphere. Much more atmospheric energy comes from the evaporation of water, water heated by the direct input of the Sun's radiation. The atmosphere is also heated by direct convection from the surface. Water evaporation becomes spectacular in hurricanes, violent air convection is the corresponding phenomenon over land, sometimes called tornados; neither extreme form is required for convection to take place. You then wrote:- "Now, realize that without the GHG absorption and emission at 14C we would instead be radiating those bands directly from the surface to space, which is (if you include microwave background radiation) at -269C?" Well? Is this going to change the average temperature? The answer depends on how thick the atmosphere is. Atmospheres are held in place by gravity, the effect of this is to make a temperature profile that increases (at the "lapse rate") with depth. Such an increase gets very high with the very deep atmospheres of planets like Jupiter; relly massive gas objects like stars reach nuclear fusion temperatures in their core, that is where their energy comes from. Earth has a surface pressure of 1 bar and its surface temperature is not much above the equilibrium temperature of 279K. Venus has a much higher surface pressure about 92bar and a surface temperature of 735K. You wrote:- "without the GHG absorption and emission at 14C we would instead be radiating those bands directly from the surface to space, which is (if you include microwave background radiation) at -269C? " Erm. no you wouldn't, you'd be in a warm bath of air at 14C, 1/2 surrounded by radiation from the ground at 14C; 1/2 from deep space at 2.7K. The thing that would finish you off would be the complete absence of H2O, you would be dead before you knew. With water and no CO2 you would only die of hunger because without CO2 nothing would grow, there would be no plant life.
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