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Patrick 027 at 14:40 PM on 8 April 2009It's the sun
"Ultimately the kinetic energy is lossed to friction," I meant "lost" "but it involves a rather small amount of energy in comparison to the thermal energy budget of the climate system." And so one can, at least on the large scale and in general, approximate the thermal energy budget without considering conversion to and from kinetic energy. -
Patrick 027 at 14:27 PM on 8 April 2009It's the sun
Gord - in case this helps visualize the situation: if I'm the white hot object and you're the red hot object, that the net direct thermal radiation exchange between them must be from me to you and not the reverse does not imply that there is no radiation in the opposite direction, for if it did, it would imply that I could not see you. The second law of thermodynamics actually implies that at any given wavelength, if you can see me, then I can see you. An optical filter could be used so that my yellow and blue wavelengths would reach you but neither of us could see each other's red wavelengths. For that matter, you're emissivity and absorptivity (they must be equal if at local thermodynamic equilibrium, and if not in local thermodynamic equilibrium, then otherwise cool objects might appear hot - as in fluorescence, etc. - the second law of thermodynamics would still apply but there would be some flow of energy not associated with a simple measure of temperature in that case (work, free energy, etc.)) could be zero at those shorter wavelengths, and then I couldn't see you and, since you wouldn't absorb any of my shorter-wavelength radiation, you wouldn't 'see me' either; the point being that seeing each other is a two way street - if I am smaller or have lower emissivity at any given wavelength, that reduces the direct radiative energy exchange in both directions between us, as I would emit less to you and absorb less from you, etc. (PS what if my shorter wavelengths were blocked by an obstacle but the red wavelengths could pass between us - well, the net radiant energy flux would still be from me to you because for a given emissivity (as a function of wavelength that is not changing in this scenario), radiant intensity increases at all wavelengths as temperature increases; it only increases much more at shorter wavelengths. If a blue hot object were in between us and it were opaque, we couldn't see each other; there would be no direct radiant energy flux between us (at the wavelengths for which this occurs). If it were transparent, we couldn't see it and it couldn't see us; our radiation would pass through it and it would be as if it weren't there. If it were perfectly reflective, we'd only see ourselves (in that direction), and effectively radiating to objects with the same temperature and getting the same back (in that direction). If it were somewhere in between, one could describe the total radiant energy flow among the three objects as the sum of three parts: the direct radiant exchange between you and me, the direct exchange between you and the blue-hot object, and the direct exchange exchange between me and the blue-hot object; each individually has a net energy transfer from warmer to cooler; the total gain or loss by each depends on the optical properties and temperatures (and sizes and distances, etc.) of all three. Yes, with radiation, what you see is what you get; the exchange of energy among objects of finite size, with neither enveloping the other, (as opposed to two infinite sheets or concentric spheres) that are farther apart, is smaller because they appear smaller to each other. The intensity - the radiant flux per unit solid angle (analogous to how bright an object looks within a given unit of the field of view) - is conserved in the absence of absorption, emission, and reflection and scattering (it is even conserved during refraction in the absence of those other things). What if there is no net energy exchange? If you wrap a white hot object in perfect mirrors (that have zero thermal conductivity and are not fluids), there is no net energy flow, but if you stepped inside the white hot object, you'd see radiation coming from the object and going back to the object equally in any two opposite directions. --- The sun heats the Earth and atmosphere. Earth loses heat to the atmosphere and space. There are convective fluxes from the surface to the troposphere. There are radiative fluxes among the surface, space, and all levels of the atmosphere; there is net radiant cooling to space from both the surface and all parts of the atmosphere, which is about equal to the total radiant fluxes from the surface and all parts of the atmosphere, since space is radiating very little (it looks like a blackbody near absolute zero). This is in total balanced by solar heating, but not everywhere, because there are net radiant fluxes among the surface and levels of the atmosphere, which all combined, and combined with convection, including horizontal heat transport, averaged over the year and over interannual variability, for a steady long-term climate, balance the spatial displacment between solar heating and longwave cooling to space. The flow of entropy is equal to thermal energy divided by temperature; for radiant energy, the entropy gained or lossed by an object by radiation is equal to the radiant energy gained or lossed divided by the temperature of the object. The direct net radiant energy fluxes between any pairing of subdivisions of the climate system is from warmer to cooler (provided the subdivisions are defined to be small enough so that they are each approximately isothermal within themselves - remember, 'local thermodynamic equilibrium'), which insures that, following the flow of energy, entropy is increasing, and as energy is conserved, entropy does not decrease. That satisfies the second law of thermodynamics. Of course the entropy of the climate system can fluctuate up and down a little as the flow of entropy and energy to space can fluctuate; this does not violate the second law of thermodynamics. If equilibrium temperature were determined by radiation along, the lowermost atmosphere would be unstable to convection (in general - not at the poles, at night, etc., but for a representative global average). Convection tends to maintain the change in temperature with height (the lapse rate) near a moist-adiabatic lapse rate - with regional variations, of course. From idea gas laws, it can be shown that warm air rising and cold air sinking, either by localized overturning (cumulus convection) or larger scale overturning (Hadley cells, Walker circulation, monsoons, extratropical baroclinic waves), converts some thermal energy into kinetic energy, as in a heat engine. Ultimately the kinetic energy is lossed to friction, thus turning into thermal energy, but with a different distribution, with higher entropy. There is not much recycling of kinetic energy to kinetic energy after frictional dissipation. However, kinetic energy can be converted back into thermal energy when wind blows from low pressure to high pressure, and cold air is forced to rise as warm air sinks. This can and does happen under some conditions. Kinetic energy is very important as winds and currents are important in shaping the climate, but it involves a rather small amount of energy in comparison to the thermal energy budget of the climate system. -
Patrick 027 at 13:28 PM on 8 April 2009It's the sun
""Temperatures of the plasma at the earth are found to be about 150,000°K, approximately a factor of ten lower than the estimates for the temperatures of the bulk of the coronal plasma found in the upper atmosphere of the Sun." Please click on the RED link above for their page and full explanation." I read it. What is the point you think it makes? -
Patrick 027 at 13:24 PM on 8 April 2009Volcanoes emit more CO2 than humans
"But the Arctic melt is caused by vulcanism, of that I am comvinced. The same goes for the AWP in Antarctica, ENSO, the PDO and AMO." But **what** is it that convinces you so? -
MattJ at 12:51 PM on 8 April 2009Solar cycles cause global warming
Isn't there another, longer cycle superimposed over this one? I seem to remember 81 or 181 years, but I can't remember which. I am surprised that the sunspot cycle could even contribute as much as .18C, seeing that most of the radiation change is in either fairly low RF frequencies or in X-ray spectrum. Then again, X-rays are well absorbed by the atmosophere, so they really do turn into heat. -
MattJ at 12:48 PM on 8 April 2009Solar cycles cause global warming
Isn't there another, longer cycle superimposed over this one? I seem to remember 81 or 181 years, but I can't remember which. I am surprised that the sunspot cycle could even contribute as much as .18C, seeing that most of the radiation change is in either fairly low RF frequencies or in X-ray spectrum. Then again, X-rays are well absorbed by the atmosophere, so they really do turn into heat. -
tommybar at 07:53 AM on 8 April 2009Why is Antarctic sea ice increasing?
Really...."Warming temperature leads to increased precipitation which increases sea ice growth."Response: This is something I discussed with Zhang, the author of the paper - he clarified that precipitation had small impact on the overall sea ice trend compared to the decrease in upward ocean heat transfer.
When I first read the paper, there was one immediate question I had about his conclusion and it was the first thing I asked Zhang - I'm surprised noone has asked it here yet. I wonder who'll bring it up... :-) -
Patrick 027 at 06:53 AM on 8 April 2009It's the sun
black2deep - "The argument that solar flair activity has not effected the earth temperature has yet to be proven. Techtonic activity according to USGS is more active in this centry than any other centery. Yet this inofrmation is being ignored. (Before anyone jumps on the train lets see which way it goes.) Volcanic activity causes cooling, not heating of the atmosphere. Dust particles tend to block the heat and cool the temperagure of the earth. However, underwater volcanic activity does two things. One, it heats the waters through magma flow welling up through the cracks within the crust, and saturates the water with CO2, two it changes the prevailing currents of the oceans. Recent events has cuased the currents to change in one part of the world, when a 100 foot tall 1000 mile wall welled up Near Indonisa. Thus, chanigng the water currents forever in that area. Before we jump on one wagon, shoulden't we be examining every aspect of this situation, rather than simply pointing to one suspect and yelling. "He's the guilty party!" Not only is it non scientific but smacks of politics, more than science. " Lack of proof or disproof can leave possibility, but when well-understood apects of a system account for the observations quite well, it's a reasonable expectation that the unknowns are not so important. Furthermore, without proposing at least some plausable or feasable mechanism to connect one phenomena to another, simply asserting that one might be connected to the other is not particularly useful - the same argument method could be used to suggest just about anything - hence the logic of Occam's razor. What is the significance of a connection? Just about everything may be connected somehow, someway, to everything else, but not all connections are equal or of the same type. If it could be shown that changes in the solar wind and geomagnetic field are somehow causing a climate change that is significant relative to anthropogenically-forced effects, it would not necessarily be a significant change in global average temperature with the same significant regional and seasonal variations as caused by any other forcing. Obviously solar UV variability will have some effect on upper atmospheric conditions that are different than greenhouse effect changes (something climatologists are aware of). The solar wind, by affecting the magnetosphere, can affect the ionosphere, but what do any of the resulting changes do to the troposphere and stratosphere? The great majority of geothermal heat flux at the surface is from the slow steady heat transport through the crust; very little is direcly from volcanism, and so it is hard for geothermal heating to fluctuate much on global and regional scales; the heat flux itself is generally on the order of 0.1 W/m2, much smaller than just anthropogenic CO2 forcing thus far; much much greater forces (Winds, climate-driven buoyancy variations, tides) shape the ocean's conditions and dynamics and variability in these dwarf any short-term volcanic effects (Panama wasn't built in a single millenium). Geologic outgassing of CO2 is very slow and can only act to change climate signicantly over time periods of at least hundreds of thousands of years. -
Patrick 027 at 04:57 AM on 8 April 2009It's the sun
Gord - With regards to the second law of thermodynamics, what it says about spontaneous heat flow only being from warmer to cooler and not the other way around - it is important to remember that this is NET flow. The NET flow of heat can be and often is the difference between two larger values, the heat flow only in one direction and the heat flow in the opposite direction. The net radiant heat flow between a red hot object and a white hot object is from the white hot object to the red hot object, but there is radiation going in both directions; furthermore, that radiation could be passing through another object which may be blue hot or as cold as space - depending on it's optical properties, it may participate in the radiant heat flows, with some net heating or cooling, but however it works out, the net heat flow between just two of whatever number of objects is involved is from hotter to colder. The difference between 390 and 342 is 48. That is the radiant cooling of the surface of the Earth to the cooler atmosphere and the cold of space. It is less than the solar heating of the surface; the difference is balanced by convection, which tends to link changes in temperature between the surface and various levels of troposphere together, because heating one part up without heating the other parts changes the convection rates in such a way as to heat up the other parts, generally; above the troposphere, convection is much less important in the global average vertical energy fluxes - but there is some large-scale overturning driven by a small upward flux of kinetic energy from below (generated by the heat engine of the troposphere when hot air rises and cold air sinks, etc.); this upper level overturning IS a refrigerator/heat pump - the kinetic energy is used to cool off parts that are colder and heat up parts that are warmer, across latitudes. -
Philippe Chantreau at 03:42 AM on 8 April 2009Why is Antarctic sea ice increasing?
Tommybar, this article discusses sea ice, which is frozen sea water. It is not dependent on snow fall. -
tommybar at 03:38 AM on 8 April 2009Why is Antarctic sea ice increasing?
Just a thought--when did all that ice down there form? Perhaps the Antarctic ice grows during the warmer periods. If it's too cold, the air is too dry for precip. So the oceans around it grow a little warmer, more snow falls down there. Ice grows larger. Either way, you guys don't know why it's growing, but it is. Sounds like yet another poorly understood system falling under the 'science is settled' banner. -
Quietman at 11:15 AM on 7 April 2009Models are unreliable
Mizimi I have posted a link to proof of Solar Wind and Magnetism being an active part of the scenario in the "It's the Sun" thread. The alarmists have been playing ignorant of the NASA findings. -
Quietman at 11:10 AM on 7 April 2009Models are unreliable
"Remember this: a climate model is really nothing more than a scientific hypothesis. If a hypothesis is consistent with observations, then it is standard scientific practice to say that such a hypothesis can continue to be entertained. In this case, that hypothesis can then serve as a basis for other subsidiary models or, in reality, subsidiary hypotheses. If the hypothesis is not consistent with observations, it must be rejected. That does not mean that human-induced climate change may or may not be real, but it does mean that (in this case) the magnitude of prospective change has—with high probability—been overestimated. That means that all subsidiary hypotheses on economic costs, strategic implications, or effects on health are similarly overestimated." TESTIMONY OF PATRICK J. MICHAELS TO THE SUBCOMMITTEE ON ENERGY AND ENVIRONMENT OF THE COMMITTEE ON ENERGY AND COMMERCE, U.S. HOUSE OF REPRESENTATIVES.. -
Quietman at 11:01 AM on 7 April 2009There is no consensus
John One of your countrymen, Dr. David Evans made the statement: "Yes, it's important to get our response right. If the alarmist are correct, then we should cut down our carbon emissions of the planet with overheat. If the alarmist are wrong, it's important not to cut back our carbon emissions or we'll create wide spread poverty unnecessary. There is no real substitute, except the get the real science right." Dr. Evans recently converted from AGW alarmist to AGW skeptic. -
Quietman at 10:58 AM on 7 April 2009Volcanoes emit more CO2 than humans
But the Arctic melt is caused by vulcanism, of that I am comvinced. The same goes for the AWP in Antarctica, ENSO, the PDO and AMO. -
Quietman at 10:55 AM on 7 April 2009Volcanoes emit more CO2 than humans
The Climate Change controversy has brought to light a correlation that seems to have been lost in history: temperature change versus solar activity, not only solar irradiance that can account for only a small change in temperature, but activity that includes solar winds and magnetic fields. See todays comment here. It's The Sun But I still feel that the Sun is only part (albeit the major part) of Climate Change. -
Quietman at 10:46 AM on 7 April 2009It's the sun
To all of you that have been saying I am wrong about The Solar Wind: Nasa says otherwise: "Temperatures of the plasma at the earth are found to be about 150,000°K, approximately a factor of ten lower than the estimates for the temperatures of the bulk of the coronal plasma found in the upper atmosphere of the Sun." Please click on the RED link above for their page and full explanation. -
Wondering Aloud at 06:29 AM on 7 April 2009Why is Antarctic sea ice increasing?
It doesn't look to me like we need any explanation other than random variation. "The paper uses a coupled ocean/sea ice model to find the predominant reason that sea ice is increasing" Translation: another computer model unverified and perhaps related to reality, perhaps not. Seems to me a stretch. We don't have the data to know much about sea ice trends either way. 30 years of records with plenty of problems isn't really something worth building models to explain, and certainly isn't enough to be useful.Response: The take home I took from the paper is that empirical measurements, not model results, show the Southern Ocean is warming - in fact, warming faster than the rest of the oceans of the world. So the conclusion that increasing Antarctic sea ice shows cooling Antartica which disproves global warming is a false conclusion. In fact, the answer is a lot more complicated than that - and a lot more interesting. -
stopphonyscience at 16:40 PM on 6 April 2009Scientists can't even predict weather
U.N. Con on Global Warming Nearly Foiled Tuesday, March 31, 2009 3:15 PM By: Philip V. Brennan Article Font Size LINK: http://www.newsmax.com/brennan/global_warming_UN/2009/03/31/198054.html The con game is about over. The attempt to portray a life-giving natural gas as a dire threat to this planet is failing rapidly, as well it should. It is becoming more and more obvious to the American people that carbon dioxide, the very substance that gives life to the world's plant life, is not a pollutant, as the global-warming hoaxers would have us believe, but a vital element that keeps the earth green and healthy. This is bad news for the would-be masters of the universe at the United Nations who have been using the supposed threat of global warming to advance their desire to turn the United States of America into a vassal state and its citizenry into its subdued subjects. If increased atmospheric levels of carbon dioxide are not causing the global climate to undergo a dangerous rise in temperatures, the United Nations has lost its strongest weapon in its attempt to assume world hegemony. Those of us who have been warning about the U.N.’s covert ambition have found an ally in Mother Nature, who has managed to cool things down despite the rapidly increasing atmospheric carbon dioxide levels during the past decade. The climate stopped warming around 1998. During the past 10 years, she's lowered the thermostat to the extent this year is moving rapidly toward the distinction as one of the coldest on record. In my 1997 series, Behold, The Iceman Cometh, I warned about the U.N.'S attempt to use global warming to achieve its dream of putting the United States in its hip pocket, writing that the U.N.'S Intergovernmental Panel on Climate Change was setting the stage for the international body's attempt at world domination. MORE: http://www.newsmax.com/brennan/global_warming_UN/2009/03/31/198054.html -
Philippe Chantreau at 02:01 AM on 6 April 2009Why is Antarctic sea ice increasing?
David, afaik, icebergs would be relevant mostly to the extent that they can prevent normal movement of sea ice if they happen to be very large and located where they can interefere with wind driven sea ice motion. About the changes in temp/density/salinity, I really don't know, would have to look at the existing litterature. Let us know if you find pointers. -
AC at 22:29 PM on 5 April 2009Why is Antarctic sea ice increasing?
i am less educated than most other forum members and i hope i am not lowering the tone with my interjections. i was just thinking that melted land ice would lower the temperature of the adjacent sea water contributing to more sea ice. the trouble with this simple argument though i reckon is that land ice isn't as salty so melted land ice and may raise the temperature of sea water. normally when i talk about ice its to do with keeping my drinks cool, that was the inception of my chain of thought to do with increasing sea ice. it imparts coldness -
David Horton at 16:47 PM on 5 April 2009Why is Antarctic sea ice increasing?
Phillippe, no I wasn't confusing them. But I was wondering if a break up of ice shelves may be contributing to greater sea ice. Or are icebergs irrelevant to sea ice extent? -
Philippe Chantreau at 10:31 AM on 5 April 2009Why is Antarctic sea ice increasing?
David Horton, do not confuse ice shelves and sea ice. Sea ice is frozen sea water, whereas ice shelves are pieces of land based glaciers floating on the sea. Ice shelves are governed by land based ice dynamics and their interactions with the marine environment. However, it is true that they have been going pretty fast. The Wilkins is about ready to break loose as well. -
David Horton at 09:42 AM on 5 April 2009Why is Antarctic sea ice increasing?
Also the latest NOAA report finds that in the Antarctica the "Wordie Ice Shelf, which had been disintegrating since the 1960s, is gone and the northern part of the Larsen Ice Shelf no longer exists." I guess this is an obvious counterpoint to the "more sea ice" finding, but I also wonder if loss/fragmentation of ice shelfs is contributing to the sea ice. That is, more sea ice is confirmation of the melting on and near land? -
walter crain at 00:11 AM on 5 April 2009Why is Antarctic sea ice increasing?
sorry this is not about antarctic ice. john, i recently came across two new "skeptic arguements" you may want to add to your list: 1)"crustal movement" (by brian valentine of the heartland institute) 2)"england temperature record doesn't show much warming" tamino has addressed the england temp record claim at his website. http://tamino.wordpress.com/2008/04/28/central-england-temperature/ i thought the more creative one was valentine's "crustal movement". he and bob ryan had an blog discussion over at capital weather and here's what brian said: "The earthquake that led to the terrible Tsunami in the Indian Ocean was a collosal event; an event of that magnitude must have been preceded by crustal shifts that resulted in the immense stresses released by the earthquake, and as I stated I have resolved a slight nutation that has a resultant North, meaning the northern hemisphere was slighly biased toward the Sun during a period of some years" the true effects of "crustal movement" on earth's orbit can be found here: http://www.jpl.nasa.gov/news/news.cfm?release=2005-009 -
Gord at 00:03 AM on 5 April 2009It's the sun
Re: #244 Here is a link to Trenberth's paper: Earth’s Annual Global Mean Energy Budget http://www.atmo.arizona.edu/students/courselinks/spring04/atmo451b/pdf/RadiationBudget.pdf The Sun is the ONLY energy source in Trenberth's Energy Budget diagram. The Earth and the Earth's atmosphere are NOT energy sources. Look at Fig.7 The earth’s annual global mean energy budget ----------------------- The Law of Conservation of Energy states: "ENERGY CAN NEVER BE CREATED OR DESTROYED". Fig.7 of the Energy Budget shows: - Incoming Solar Energy, at the top of the atmosphere, to be 342 w/m^2. - Surface Radiation of the Earth is 390 w/m^2!!! EVEN IF ALL THE INCOMING 342 WATTS/M^2 OF SOLAR ENERGY REACHED THE EARTH'S SURFACE (which it does not)...IT IS IMPOSSIBLE FOR THE EARTH'S SURFACE TO RADIATE 390 WATTS/M^2!! Since the SUN is the ONLY energy source....Trenberth has the Earth's Surface CREATING ENERGY! This is ABSOLUTE PROOF that Trenberth's Energy Budget VIOLATES THE LAW OF CONSERVATION OF ENERGY! -
David Horton at 22:29 PM on 4 April 2009Why is Antarctic sea ice increasing?
Good to have you back John. Obviously a complex topic. Similar to the increase in snow fall on Antarctica as a result of the seas warming. In both cases the outcome is counter-intuitive to what would be "common sense" and therefore gets picked up by denialists as evidence of failure to warm, when in fact it is the opposite. The contrast to the Arctic (where estimates of time to an ice free summer have just been revised downward again) is stark. But of course the Arctic and Antarctic are similar only in being polar and icy. In most other ways they are quite different, and their responses to a warming planet are also consequently different. -
black2deep at 02:32 AM on 4 April 2009It's the sun
Okay, let me ask this question. If we suddenly decrease the amount of CO2 by lets say, 10%. How much will that drop the over all global temperature? How much moisture is in the atmosphere at this moment? Where will that moisture go when the temperature suddenly drops? Has anyone considered the results of a sudden drop in over all CO2 content in the atmosphere. Tom .R -
black2deep at 01:50 AM on 4 April 2009It's the sun
I have read some toung in cheek remarks about volcanic activity in the oceans. Even a bit of back handed humor. The ability to simply negate the data or simply make the statment that "I don't have the time to investagate the possibilities" seems a bit negitive. Can anyone be so positive of a condition that they simply ignore other possibilities? Solar radation is an extream factor in earth heating or cooling. Any changes in the suns activity will cause weather and temperatures change. The argument that solar flair activity has not effected the earth temperature has yet to be proven. Techtonic activity according to USGS is more active in this centry than any other centery. Yet this inofrmation is being ignored. (Before anyone jumps on the train lets see which way it goes.) Volcanic activity causes cooling, not heating of the atmosphere. Dust particles tend to block the heat and cool the temperagure of the earth. However, underwater volcanic activity does two things. One, it heats the waters through magma flow welling up through the cracks within the crust, and saturates the water with CO2, two it changes the prevailing currents of the oceans. Recent events has cuased the currents to change in one part of the world, when a 100 foot tall 1000 mile wall welled up Near Indonisa. Thus, chanigng the water currents forever in that area. Before we jump on one wagon, shoulden't we be examining every aspect of this situation, rather than simply pointing to one suspect and yelling. "He's the guilty party!" Not only is it non scientific but smacks of politics, more than science. Tom R. -
Gord at 22:56 PM on 3 April 2009It's the sun
Re: #246 and #247 The Sun is the ONLY energy source in Fig.7 of Kiehl & Trenberth's Energy Budget Diagrams. In-coming Solar energy and out-going IR energy is balanced at the top of the atmosphere. However, below the upper atmosphere Conservation of Energy is violated. The Law of Conservation of Energy always applies....including the Earth's surface. The Surface of the Earth absorbes 168 w/m^2 of Solar Energy (and is the ONLY energy source). The Atmosphere and the Earth are NOT energy sources. The Earth's surface is shown to be radiating 390 w/m^2. The Back Radiation from the atmosphere (shown to be absorbed by the Earth's surface) is 324 w/m^2. Both these quantities (390 w/m^2) and (324 w/m^2) exceed the ONLY energy source (the Sun) which provides only 168 w/m^2. The Law of Conservation of Energy states: "Energy can never be created or destroyed". There is, obviously, energy "creation" in this situation....an impossible outcome. ------------------ MattJ's post with reference to the 2nd Law of Thermodynamics states: "The application of the 2nd Law is not that straightforward. This becomes more clear if we use a better source for the wording of the Law, better than Wikipedia or the Hyperphysics site. I use The Pauli Lectures on Physics Vol 3, which is on Thermodynamics, and has: "There does not exist a device which, working in a cycle, permits heat to be transferred from a reservoir at one temperature to a reservoir at a higher temperature without compensating changes (that is, unless mechanical work is done or energy is added by some other means)". I fail to see the difference between MattJ's preference for the 2nd Law definition as compared to the Hyperphysics link, which is: "Second Law of Thermodynamics: It is not possible for heat to flow from a colder body to a warmer body without any work having been done to accomplish this flow. Energy will not flow spontaneously from a low temperature object to a higher temperature object." In fact, MattJ found it necessary to explain what "compensating changes" meant....which is clearly stated in the Hyperphysics definition. Both defintions say the same thing....as one would expect. ------------------------- MattJ seems to have missed the point of the Sun being the ONLY energy source. He said... "But we have both of these compensating changes: mechanical work is done on the atmosphere itself as it is heated by radiation, and energy is added from the sun." What MattJ is trying to say is that there is "mechanical work" done to move heat energy from a Colder atmosphere to a Warmer Earth. This would have to be the equivalent of a Refrigerator in the sky....which does not exist. In fact, actual measurements conducted at the Physics Dept.of Brigham Young University, Utah clearly shows this: ------------------------ Solar Cookers and Other Cooking Alternatives "The second area of solar cookers I looked at was their potential use for cooling. I tested to see how effective they are at cooling both at night and during the day. During both times, the solar cooker needs to be aimed away from buildings, and trees. These objects have thermal radiation and will reduce the cooling effects. At night the solar cooker needs to also be aimed straight up towards the cold sky. During the day the solar cooker needs to be turned so that it does not face the Sun and also points towards the sky. For both time periods cooling should be possible because all bodies emit thermal radiation by virtue of their temperature. So the heat should be radiated outward. Cooling should occur because of the second law of thermodynamics which states that heat will flow naturally from a hot object to a cold object. The sky and upper atmosphere will be at a lower temperature then the cooking vessel. The average high-atmosphere temperature is approximately -20 °C. So the heat should be radiated from the cooking vessel to the atmosphere." http://solarcooking.org/research/McGuire-Jones.mht This link shows that heating cannot occur from the atmosphere. In fact, the article shows how to COOL items placed in the Solar Oven at NIGHT AND DAY! All you have to do is point the Oven away from the Sun during the Day and the Oven will transfer heat from the WARM object in the Oven to the COOLER atmosphere! It can even be used to produce ICE when the ambient air temp is +6 deg C! "If at night the temperature was within 6 °C or 10°F of freezing, nighttime cooling could be used to create ice. Previous tests at BYU (in the autumn and with less water)achieved ice formation by 8 a.m. when the minimum ambient night-time temperature was about 48 °F." This confirms the validity of 2nd Law of Thermodynamics....heat energy CANNOT flow from Cold to Warm objects. And, there is no Refigerator in the sky to force energy flow from Cold to Warm. ------------------------------ PS: Matt, I don't see any relevance of your posts to my Post #244. -
MattJ at 17:49 PM on 3 April 2009It's the sun
Post #246 was really directed as a response to #243, not #244. Yet it is indirectly applicable to #244 also. But this post is directed to another subtopic of #243, the alleged violation of the 2nd Law of Thermodynamics. The application of the 2nd Law is not that straightforward. This becomes more clear if we use a better source for the wording of the Law, better than Wikipedia or the Hyperphysics site. I use The Pauli Lectures on Physics Vol 3, which is on Thermodynamics, and has: "There does not exist a device which, working in a cycle, permits heat to be transferred from a reservoir at one temperature to a reservoir at a higher temperature without compensating changes (that is, unless mechanical work is done or energy is added by some other means)". But we have both of these compensating changes: mechanical work is done on the atmosphere itself as it is heated by radiation, and energy is added from the sun. Besides: the radiation budget diagrams like Kiehl and Trenberth's Fig. 7 do not SHOW a cycle. So in order to show an alleged violation, one would have to show how to use what IS shown in Fig. 7 to construct a cyclic process transferring heat to a hotter reservoir without compensating changes. This is actually not a simple construction, which is why people do not usually resort to it. Instead, they analyze such situations by using, for example, the Gibbs variational method, which automatically guarantees compliance to both First and Second Laws. -
MattJ at 17:34 PM on 3 April 2009It's the sun
Re: #244: The diagram in Fig. 7 of Kiehl & Trenberth's is quite misleading. Numbers that look like they are total fluxes in one direction or the other are not. To get the right equation to express Conservation of Energy at the Earth's surface, one must refer to the previous page, which has: SW = LW + LH + SH where: LW = Surface Radiation - Back Radiation Absorbed by Surface = 396-24=66, just as Trenberth said. SW is the net (downward) shortwave flux at the surface, which is called Incoming Solar Radiation Absorbed by Surface which is 168 (we can ignore reflected) LH is latent heat, SH is 'sensible heat' (not in Fig. 7). So this gives 168=66+78+24, which is correct for expressing Conservation of Energy at the surface. -
Philippe Chantreau at 17:18 PM on 3 April 2009Why is Antarctic sea ice increasing?
Actually, I did not link it but gave the reference and abstract in post #253 of the thread. It appears to be the very same paper but published in the Journal of Climate instead of UW. I would have linked the pdf from UW if I had known it was there. Author(s): Zhang JL Source: JOURNAL OF CLIMATE Volume: 20 Issue: 11 Pages: 2515-2529 Published: JUN 1 2007 Times Cited: 1 References: 34 Abstract: Estimates of sea ice extent based on satellite observations show an increasing Antarctic sea ice cover from 1979 to 2004 even though in situ observations show a prevailing warming trend in both the atmosphere and the ocean. This riddle is explored here using a global multicategory thickness and enthalpy distribution sea ice model coupled to an ocean model. Forced by the NCEP-NCAR reanalysis data, the model simulates an increase of 0.20 x 10(12) m(3) yr(-1) (1.0% yr(-1)) in total Antarctic sea ice volume and 0.084 x 10(12) m(2) yr(-1) (0.6% yr(-1)) in sea ice extent from 1979 to 2004 when the satellite observations show an increase of 0.027 x 10(12) m(2) yr(-1) (0.2% yr(-1)) in sea ice extent during the same period. The model shows that an increase in surface air temperature and downward longwave radiation results in an increase in the upper-ocean temperature and a decrease in sea ice growth, leading to a decrease in salt rejection from ice, in the upper-ocean salinity, and in the upper-ocean density. The reduced salt rejection and upper-ocean density and the enhanced thermohaline stratification tend to suppress convective overturning, leading to a decrease in the upward ocean heat transport and the ocean heat flux available to melt sea ice. The ice melting from ocean heat flux decreases faster than the ice growth does in the weakly stratified Southern Ocean, leading to an increase in the net ice production and hence an increase in ice mass. This mechanism is the main reason why the Antarctic sea ice has increased in spite of warming conditions both above and below during the period 1979-2004 and the extended period 1948-2004 -
Patrick 027 at 14:44 PM on 3 April 2009Volcanoes emit more CO2 than humans
"A new dynamical mechanism for major 1 climate shifts" Should be "A new dynamical mechanism for major climate shifts" -
Patrick 027 at 14:40 PM on 3 April 2009Volcanoes emit more CO2 than humans
... because they compare the behavior they found in observations to that they find in climate models and find similar behavior. Those climate models produce global warming in response to increased CO2, and do not incorporate submarine volcanism or any particular patterns in volcanism so far as I know, and most definitely do not include tides from other planets. Furthermore, Tsonis et al do not show in this paper why this pattern occurs, nor do they show that changes besides the longer term warming are entirely associated with this particular pattern (some changes in ENSO and other such modes of variability could be due to AGW and other externally-forced changes more directly; some could be a result of the mechanisms of this pattern, but this pattern could be affected by externally-forced climate changes in some way.). They did not mention the AMO, which I think has a similar time scale and has been said to vary between partially masking and adding to anthropogenic global warming. The only statement that raises a conflict with some of the current body of knowledge is that the lull in global warming between 1940 and 1970 may be less due to variations in anthropogenic aerosol cooling than thought and more due to internal variability than thought. I'm not sure how significant an adjustment to current understanding would truly occur if this paper and subsequent work lead to a new understanding of the matter. I did once read, some years ago, that a person had identified a pattern in the paleoclimatic record, which was suggested to fit the pattern in the historical record of changes in the 20th century in global average surface temperature, with warming up to about 1940, cooling to about 1970, and warming after about 1970 - but with a notable difference, that the warming has been greater and the cooling less (in fact there really was not an extended period of cooling in the global average) than would be expected from the paleoclimatic pattern alone - this would be consistent with externally-forced global warming superimposed on some natural 'cycle'. Whether the paleoclimatic pattern is the same phenomenon covered by this paper, or due to AMO, or if the phenomenon in this paper is organized by the AMO - well, that I don't know; who does? -
Patrick 027 at 12:25 PM on 3 April 2009Volcanoes emit more CO2 than humans
About this: "Synchronized Chaos: Mechanisms For Major Climate Shifts" See Tsonis et al: "A new dynamical mechanism for major 1 climate shifts" http://www.uwm.edu/~kravtsov/downloads/GRL-Tsonis.pdf What they have found, based on their interpretation, is that there are times when some of the leading modes of variability vary together (become synchonized), and when the strength of that synchronization then increases, this destroys the synchronization and causes shifts in temperature and variability patterns (ENSO). However, they did not attribute longer-term average warming to this process. Nor did they attribute these changes in variability to volcanism or tectonics - not that this alone implies it cannot be so, but ... it seems to me that it is more likely their findings are incompatible with your hypothesis then with most of what I've been saying.... (to be continued?)... -
Philippe Chantreau at 03:56 AM on 3 April 2009Why is Antarctic sea ice increasing?
This appears to be the same Zhang paper I linked in the Arctic Sea Ice thread, thanks for picking up on it John, interesting stuff.Response: It is interesting stuff, I was very surprised to find the Southern Ocean has been warming so much - I thought it must be cooling if sea ice was increasing. But I must confess I missed your link (will have another look). I've been sitting on this paper for over 6 months - I started writing this post last September! -
PT_Goodman at 16:30 PM on 2 April 2009The link between hurricanes and global warming
Perhaps this is a bit OT, but I'm wondering if, from the above graph and text, any qualitative inferences can be made about the _apparent_ recent increase in extreme weather events around the world. In an Amazon Discussion (of all places), I suggested that one could not prove that the flooding in North Dakota was due to GW or due to global cooling, if that's your predisposition. My uncertainty: is weather (worldwide) is now truly more dynamic, or does weather simply appear to be so, due to better/more reporting of extreme weather events. Any comments or links that may help provide some insight are welcome. -
dgranrath at 10:52 AM on 2 April 2009Models are unreliable
I am trying to remain objective as I learn more about the Physics of climate change. This has not been easy amid all the opinion and hyperbole surrounding the subject. However, this web site has impressed me with the intelligence shown by the author and the commentators. I have some questions related to the GCM controversy. Perhaps someone can point out primary references where they can be answered. 1. What is the "predictive" variability between climate models? 2. Do they all have the same free model parameters (i.e. fudge factors)? 3. If so, are these parameters set to the same values to accurately fit historical data? It would raise my "skeptical" level if, in fact, the GCMs contain significant differences in their predictability and technical structure. -
Ian Forrester at 08:10 AM on 2 April 2009Why is Antarctic sea ice increasing?
John, what affect could the water from the melting ice cap have on the size of the ice pack? The water surrounding the Antarctic should be less salty and thus freeze at a higher temperature. Could this be partially responsible?Response: Funny you should mention that - when I first started researching this topic, that was the first thought I had. Well, not the impact of fresh meltwater but of calving land ice. None of the papers I read find calving land ice or meltwater have an impact on sea ice levels. Nevertheless, I ran the idea by Eric Rignot who has done a lot of research into Antarctic land ice loss. His response:Glacier ice and sea ice do not have much in common. My paper is about the loss of land ice; it has nothing to do with sea ice. Vice versa. The stability of the sea ice cover in the antarctic does not mean anything in terms of land ice. Almost feels like comparing water from the ocean and water from lakes.
Sorry I don't have any harder numbers for you on that (if anyone else cares to chase down hard figures, I'd be appreciative :-) -
Quietman at 09:37 AM on 1 April 2009Climate's changed before
ps I am retired on a healthy pension, I think I know about the real world, but you still have much to learn. Read my comments and links in the volcanos thread. -
Quietman at 09:35 AM on 1 April 2009Climate's changed before
Well Dave, I have been around long enough to have experienced warm winters before. Growing up on Long Island we had snowball fights wearing no more than jeans and t-shirts. You can fool the kids but you can't fool us old timers, sorry. -
Quietman at 09:27 AM on 1 April 2009Volcanoes emit more CO2 than humans
ps The links in Posts 5 and 6 (especially the first link in 5. Post 13 has the Tectonic Thermostat link and the links in 83 support me in that they can be rapid. Then "Synchronized Chaos: Mechanisms For Major Climate Shifts" link at 107. and 178 "Magma chockfull of silica is viscous (think warm, gooey taffy) and traps lots of gases." refers to Alaska's eruptions, evidence of the increase in subduction there. -
Quietman at 06:32 AM on 1 April 2009Volcanoes emit more CO2 than humans
Pat Re: "statistical study of the raw data for yourself" Yes but in MY field, not in climatology. ie. I understand correletions, nobody understands climate yet. Re: "You did post a source about ENSO being connected to volcanos via volcanic aerosol climate forcing - noting that not all El Ninos are caused that way." No, not "via volcanic aerosol climate forcing", an article of SIGNALING the beginning of a cycle, ie. the volcano erupts and is used as a SYMPTOM. Re: "You've never actually posted any source that links any of that to planetary alignments. You did post a source about a planet that would be heated sufficiently by tidal deformation to be kept habitable whereas it would not otherwise be so. Tidal heating of the Earth is a fraction of geothermal heat release, most of which is slow and steady, related to conduction through the crust, and in total is puny in comparison to just the recent changes in climate radiative forcings." If you refer to the "Thermostat article", you make the assumption of an earth with a constant rate. That constant rate was disproved by the findings in Nepal and Tibet of just how old the Himalyas are (they are MUCH more recent than thought). It was also proven false by further studies in both the Rockies and the Andes. They are much younger than thought. In my hypothesis I make a couple of assumptions (as in any hypothesis). I assume first that Rhodes Fairbridge was correct in the "Solar Jerk" and hypothesize that this same jerk is applicable to the Earth. This explains why plate tectonics occur in "fits and spurts". The second assumption is that the ENSO is related to the South AMerican subduction zone. Unfortunately when I read the hypothesis on the tectonic cause of ENSO I was doing research for my own curiosity and did not note the website (all I remember was it was a dot gov). I had cut and paste the hypothesis to notepad and saved it for my own reference. If I relocate the site I will post it here. In the meantime, expect El Nino soon. Volcano in Chile spews lava and blasts ash 12 miles into sky But there are more signs of current activity: Tongan Inspection Team Heads to Undersea Volcano And more arctic seafloor recycled here: Ash Falls on Anchorage as Volcano Keeps Spewing The third assumption is that clouds cool and lack of clouds allow IR warming, ie. Spencers work on positive vs negetive feedback to GHGs. Sorry, I don't need math here to prove he is right, it's common sense. -
Patrick 027 at 04:27 AM on 31 March 2009Volcanoes emit more CO2 than humans
Re 201 - so you've actually done a statistical study of the raw data for yourself? You've never actually posted any source about submarine volcanism being linked to ENSO. You did post a source about ENSO being connected to volcanos via volcanic aerosol climate forcing - noting that not all El Ninos are caused that way. You've never actually posted any source that links any of that to planetary alignments. You did post a source about a planet that would be heated sufficiently by tidal deformation to be kept habitable whereas it would not otherwise be so. Tidal heating of the Earth is a fraction of geothermal heat release, most of which is slow and steady, related to conduction through the crust, and in total is puny in comparison to just the recent changes in climate radiative forcings. -
Lee Grable at 07:30 AM on 30 March 2009Arctic sea ice melt - natural or man-made?
Same with your 'tectonic plate' arguement. You just made that up so you could keep "debating". -
Lee Grable at 07:05 AM on 30 March 2009Arctic sea ice melt - natural or man-made?
Quietman says, "CO-2 is not a pollutant". I'm dissapointed. I would think that someone as obviously intelligent and educated as you are (no sarcasm) would'nt have to resort to the most simplistic and ignorent "arguements" against the MMGW concensis curculating around. No one is argueing that point. Like no one is argueing about whether plants need CO-2 to live. It's nothing but a manufactured arguement. You can't argue the actual facts of this subject, so you have to make up something to maintain the illusion of a debate. Also, you might want to ask Jim Lovell what he thinks of that claim, concidering that he's had actual experience dealing with CO-2 'pollution. -
Lee Grable at 06:40 AM on 30 March 2009Arctic sea ice melt - natural or man-made?
"The green socialist threat". Wow, I wish I had that line when I was a kid and my mom made me do the dishes. I would'nt have had to wash another dish. Of course, my sisters would have done the same thing, and then mom would have decided that since no one else was washing the dishes, she wouldn't either. And my dad? Please! By this time however, we'd all be dead from food poisoning, so problem solved! -
Lee Grable at 06:24 AM on 30 March 2009Arctic sea ice melt - natural or man-made?
"The green socialist threat". Wow, I wish I had that line when I was a kid and my mom made me do the dishes. I would'nt have had to wash another dish. Of course, my sisters would have done the same thing, and then mom would have decided that since no one else was washing the dishes, she wouldn't either. And my dad? Please! By this time however, we'd all be dead from food poisoning, so problem solved! -
Patrick 027 at 05:34 AM on 30 March 2009Arctic sea ice melt - natural or man-made?
"Making Carbon Markets Work (extended version) Limiting climate change without damaging the world economy depends on stronger and smarter market signals to regulate carbon dioxide" David G. Victor, Danny Cullenward http://www.sciam.com/article.cfm?id=making-carbon-markets-wor "Climate Change Is Happening, Effects Will Be Severe, Now What Will It Cost to Fix It? Could it be true that staving off the severe effects posed by climate change won't impose ruinous costs? The IPCC thinks so" David Biello http://www.sciam.com/article.cfm?id=climate-change-happening-effects-severe-what-cost-fix-it "A Solar Grand Plan By 2050 solar power could end U.S. dependence on foreign oil and slash greenhouse gas emissions" Ken Zweibel, James Mason, Vasilis Fthenakis http://www.sciam.com/article.cfm?id=a-solar-grand-plan “Engineering Silicon Solar Cells to Make Photovoltaic Power Affordable” Steven Ashley http://www.sciam.com/article.cfm?id=engineering-silicon-solar-cells My comments 187, 200, 225, 229, 236, 254, 317, 322, 338,...(a few more in the pipeline) at: http://www.realclimate.org/index.php/archives/2009/03/olympian-efforts-to-control-pollution/langswitch_lang/tk And 324, 334-336, 338, 368, 387 and 388 (skip PART II if you want to), 393, 398 (and comments surrounding that by others), 412 (just entered, may not appear and might not be >412) at: http://www.realclimate.org/index.php/archives/2009/03/advice-for-a-young-climate-blogger/langswitch_lang/tk
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