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Everything posted by Samm

  1. I think quality shouldn't be sacrificed for speed. As far as I can tell, some of the people here on this forum seem incredibly knowledgeable within their fields (I'm definitely not one of these people). But they've got lives to lead, and don't really have a great deal of time for answering everyone's questions. Maybe it's a good idea to read good physics books. I know that when I get out of high school (this is the final year, the pressure is on!), the first things on my reading list will be penned by Richard Feynman.
  2. Looks like we're making progress. To be fair, you looked as if you were attempting to discredit General Relativity, by stating: As if that somehow meant something, other than General Relativity isn't 100% perfect. If temperature is the average kinetic energy of particles randomly bouncing off each other, in different directions, then no. Photons are the messenger particles for the electromagnetic force. Entropy and photons have little to do with one another. Entropy is just a measure of how much non "useful" energy there is in a system ie. how much energy can't be used to produce work. Or alternative the number of ways one can rearrange the atoms of an object and have the object still look the same, although I'm not too sure on that one. Wait... Are you confusing this with the idea of the heat death of the universe? A state where close to maximum entropy is reached, pretty much at the end of the universe. Supposedly all the matter evaporates into photons or decays into leptons No. There is a such a thing as zero point energy, which is the energy that a something has in its ground state.
  3. I think it's where the electrons or other charged particles travel faster through a medium than the speed of light in that medium. And then this produces radiation through some mechanism that I don't understand. Edit: On further research it has to be a dielectric medium. But I don't really know what that means either.
  4. Kinetic energy and quantum mechanics IS physics. What you're saying doesn't make any sense. It's not physics. I mean from what I can see, you're trying to establish that objects stop in time because measurements are events that don't occur continuously. As you're very keen to point out, measurements are distinct from the object. The measurement is just an image that we can see of what's going on, so... what does that have to do with any objects actually stopping in space, let alone time? And if a law of thermodynamics was disproved, it would be the largest science news was disproved, it would likely make headline news and be everywhere. I don't think we have yet seen that. General Relativity doesn't say "EVERYTHING IS RELATIVE". It doesn't. The laws of physics apply to all reference frames, to the same degree. It's just the way it works. Liquid helium is a superfluid under the correct conditions. Superfluids have high thermal conductivity, not infinite thermal conductivity. They are very strange, but it's not like they actually break any rules. They are frictionless, yes, but that is well documented and it doesn't actually void the laws of physics. It's funny that you say this because Dr Rocket seems to have the famous Nobel Prize-Winning Quantum Physicist Richard Feynman as his picture. Which would be odd for someone who doesn't know anything about Quantum Mechanics, now wouldn't it?
  5. I wouldn't agree entirely on that. If it is man-made and we are in fact causing global warming or climate change, we can actually take action to reduce greenhouse gas emissions and reduce hence future warming.
  6. Although somewhat speculative, Carl Sagan's Pale Blue Dot was excellent. Wonders of the Universe, by Brian Cox is probably my favourite book out of all the books I've read.
  7. That would be true if the car was on a frictionless road, driving in a perfect vacuum.
  8. Apologies for the missing equation. For some reason I can't edit the post, so here it is:
  9. About the transformer, I meant a power source which, while DC, could have its voltage changed. Sorry for the confusion. And yes, the pentiometer seems to fit exactly with what I remember about the circuit design.
  10. Lawrence Krauss once proposed something like that. He basically shows that the universe has no total energy (gravitational potential energy is negative) because it's geometry is flat. Now the interesting part is that with no total energy, the universe could have come from a quantum fluctuation; virtual particles popping in and out of existence.
  11. Now I remember distinctly that one of my science teachers described to me a circuit that one could use to measure the potential difference of a galvanic cell; it's E0 value, ie. it's electric potential where there is no current. It involved a transformer, a micro-ammeter, the galvanic cell and a rheostat. I want to know how it works and possibly get more info on the subject. Cheers.
  12. There's a formula for the force of gravity upon two objects: , Where: F = the force between the masses. G = the gravitational constant m1 = the first mass m2 = the second mass r = the distance between either mass. It's called Newton's Law of Universal Gravitation. If we're talking about an object falling towards earth, we can make the mass of earth m1 and the mass of the falling object m2. Now it just so happens that the acceleration of an object is equal to the force on it divided by its mass (a = F/m). So that means we can divide Newton's Universal Law of Gravitation by m2 (the mass of the falling object). So we get: And you'll notice that m2, the mass of the falling object has nothing to do with its acceleration. This equation will apply on pretty much any planet, moon, object etc. In fact astronauts on the moon have performed an experiment that supports this result:
  13. First of all, I'd like to point out that there is no such thing as an "energy particle". There are messenger particles of different forces which can transmit energy (eg. the photon), but inside them we don't find "energons". Energy is an abstract concept; the ability to do work. These particles merely possess that ability. You also seem to have a very strange understanding of Einstein's E=mc2 formula. It simply shows that matter and energy are equivalent that energy has mass and that matter has energy, and that you can change matter into energy and vice versa. If you're interested have a read of the wikipedia article here.
  14. It appears as if 2010 was the warmest year on record, equal with 2005, according to NASA and NOAA. It's interesting to note that the latter half of the year was actually influenced by a strong La Nina event, which is usually associated with cooler conditions. NOAA source NASA source
  15. First of all, it is not exactly the same. The most recent one lasted longer and warmed more than the previous periods of warming. And what are the odds of a non-linear chaotic system producing similar outputs if the most of the inputs remain much the same. I don't see it is as too improbable. Well, I can cite a paper that supports these statements. I can't prove it, I can provide evidence in it's favour. Here is a graph depicting the temperature rise due to the various different influences on climate. From Lean, J. L., and D. H. Rind (2008). Additionally, the "current lack of warming" isn't really doing the data justice. It's a currently lack of statistically significant warming, at the 95% significance level. Here's what Phil Jones would like to say: First of all, according to the graph above, the "current lack of warming", which isn't really a current lack of warming, can be explained by a decrease in the solar irradiance, and a decrease in ENSO forcing. The period of cooling seem between 1880-1910 according to the graph, appear to be due to volcanic aerosols and low levels of solar irradiance, coupled with a low level of anthropogenic forcing. Okay, I understand what you're saying. Natural influences appear to influence the short-term greatly, but over the long-term CO2 seems to win out. Any explanation that says it's only CO2, or only natural causes, behind any climate phenomenon, is likely to be wrong. I concede that solar irradiance, appears to have helped along the greenhouse effect (see graph), and feedbacks play a significant role. I'd consider it to be probably guilty. Not 100% sure, but it's definitely better safe than sorry. We'd have to figure out the actual rates of temperature rise for those spikes. Additionally, that is only one proxy, it doesn't invalidate reconstructions that either take it's data into account, or use a number of other proxies. Yes, true, however, my point is that you shouldn't base your conclusions on just one new paper, especially when it contradicts a whole number of others. Indeed. The former rather than the latter.
  16. The graph, it's a strawman. That doesn't show the actual level of CO2 in the atmosphere, it shows the level of CO2 Emissions. Additionally, there is actually a delay between the time the CO2 is emitted and the entirety of its effects are felt. There appears to be nothing wrong with hypothesis 1. The fact is that although the warming periods are similar, the causes of them can differ. ENSO oscillations and other climatic variations still influence the current warming we are seeing. The fact is that the warming period in the past was probably caused by such effects, while today's warming is probably anthropogenic and influenced by such effects. That could in part explain why the the current warming is very similar to the warming in the recent past. The reason latest period of warming is considered anthropogenic is because we know that we emit greenhouse gases, and there appears to be little else that can account for the recent warming. Solar Irradience has remained much the same, ENSO forcing isn't high enough and fluctuates far too rapidly and volcanic eruptions should be cooling the climate. Despite all this, we are seeing significant levels of warming. The similarity between the warming we are experiencing at the moment and the warming in the past doesn't invalidate this reasoning. Temperature changes of 1 degree/century do seem out of the ordinary. In fact coming out of the ice-age had a slower rate of warming than 1 degree/century. Then again, I don't suppose that actually accounts for decadal or centennial fluctuations. Additionally, nothing of that magnitude or rate appears in the temperature reconstructions over the past 2000 years. This in effect means that either temperature reconstructions are completely and utterly fail, or that 1 degree/century warming doesn't happen all that often, without anthropogenic interference. I believe that latter is more likely. Sure, if that new figure is correct, that means that increases in CO2 have less of an effect on the climate than originally expected. However, it should be noted that figure is in the minority and disagrees with many other papers. That figure although reassuring should probably be taken with a pinch of salt. Though it is true that everything is fundamentally influenced by other things, it would probably be more correct to consider everything to be a feedback, instead of a forcing. However, the distinction should be made between feedbacks of the internal and feedbacks of the man-made and external. The fact is that all significant variations in feedbacks are internal or man-made. The fact is that the internal feedbacks are driven by for want of a better word, climate, while man-made feedbacks are not, and influence climate.
  17. That's the reasoning I used. But then, I'm some silly high school student.
  18. I like to think of it this way: xn=x(n+1)/x Although the above equation is pretty obvious, it helps to illustrate the idea. Let x be 4 and n be 0. 40=4(0+1)/4=1 You could think of it another way. When multiplying or dividing by indices, you add or subtract the indices. So: 41/41=1 Which could be rewritten as: 40=1 I hope it makes more sense now.
  19. Yeah, I'd like to see it in literature as well. It's more permanent, and adds a sense of reliability to the source. Speaking of which, that the constant 0.5 degree/100 years with a superimposed 60 year harmonic cycle, what does it show? Right. I suppose that speaks about the general niceness of climate scientists then. Yeah, that sounds quite severe. I agree what you're saying in that abrupt climate change can occur, but that is usually caused by very extreme circumstances. Such circumstances don't seem to be occurring at the moment, the only thing extreme appears is the level of greenhouse gas increase. This probably lends some justification to the belief that we may undergo serious climate change in the future. Far more serious than we are experiencing at the moment. Given that greenhouse gases affect temperature, would you agree with the notion that steps should be taken to minimise greenhouse gas emissions? Right. I thought so, but you never really know for sure until somebody explains them to you. Yeah, I suppose I was probably wrong about currents only having a few inputs, I neglected to include the input of plate tectonics and sea levels. However, I don't believe that plate tectonics, being awfully slow moving would be able to affect the ocean currents enough to produce the significant warming we are experiencing at the moment. As for sea levels, I believe that they are a feedback of climate. I don't think there's very much that affects cloud cover that isn't a feedback of climate. Okay, I suppose I was wrong there. Well, I doubt that the data was truncated solely because it casted doubt on their methodology. It is cut out, because the data is wrong from there on. If you are trying to do a reconstruction, that displays the temperatures as accurately as possible, truncating the data that is wrong, from when it starts to be wrong is understandable. I agree, it would be better to show the divergence and explain it, but there is no current explanation for it. In fact, it would probably better to just be honest about it and show the proxies to the present and mention that from 1980 onwards they disagree with the instrumental record for reasons unknown. However, it didn't but that doesn't entirely invalidate the data we are seeing.
  20. Thank you. I find it rather funny that the people in the comments sections often devolve into flaming on those climate blogs. Hmm. I probably should do a little more reading into that. Yeah. That's pretty deplorable. I don't think anyone really deserves that sort of treatment for, almost anything. I mean, what's the writer of the email trying to do? Curry's not even a skeptic herself.. However, Spencer does seem a little weird. I can understand getting aggravated by his current predicament, but he seems a lot more accusational than that. GCRs? I'm not exactly sure what that stands for, sorry. However, changes in ocean currents are they influenced by anything external greatly? I mean, it seems to me as if they're just a feedback of temperature, salinity and the Coriolis force. All of which are either internal, salinity and temperature or relatively stable, the Coriolis force. Okay, that'd be great. That is true. the resolution would prohibit us from seeing the more extreme and short term changes in temperature. I don't dispute that Little Ice Age shows up on that graph, although, it doesn't really appear on the peer-reviewed global reconstructions. So, I'm saying that I'm unsure of it's magnitude. Sure, that would be a good thing. Especially if it could be calibrated against the instrumental temperature record. Although this graph is probably fairly accurate, it is only a proxy reconstruction and lacks the instrumental temperatures in the last 150 years. The actual paper says the following: Basically, they haven't provided the instrumental record for comparison and to construe this as a complete temperature reconstruction would be a little dishonest. It should be considered a proxy-reconstruction only. I believe that Swansont addressed this. Well... I can't see the issue with truncating data that disagrees with more accurate data. The proxies are probably less accurate than the instrumental record, and in order to make it a valid reconstruction you've actually got to reconstruct the temperatures to the best of your ability. Including data that is known to be wrong after a certain point on the graph can be misleading especially if the graph is meant to be a complete(ish) record of temperatures. I wouldn't consider it Cherry Picking. Although the Divergence Problem is unexplained, it is known to exist among scientists. I'm pretty sure that they understand that tree-ring data starts to diverge from the instrumental record from around the 1950s onwards. It would be dishonest to include data that is known to be inaccurate from that point onwards. It would be akin to attempting to carbon date dinosaur fossils and then talk about their age based on the carbon dating. Carbon dating works, only within a certain range of circumstances, and dinosaur fossils aren't included in that set of circumstances. I imagine it would be a similar case here.
  21. I can say, I didn't know the hydrogen reacted continually, during some of the more energetic alkali-water reactions. Yeah, the hydrogen definitely combusts quickly during the pop test, I would almost describe it as a small explosion.
  22. I'm pretty sure that's what makes the "pop" test work. You light a flame near the supposed hydrogen source and see if you can hear a "pop". It only works with relatively large quantities of hydrogen. It's a simple experiment and was actually performed by one of my science teachers. It also should be noted that a number of the alkali metals react in a very nasty way to water. Some of the more inert ones produce bubbles. Which are probably hydrogen and if there's enough bubbles, it might be worthwhile doing the pop test. On a slightly different note, I remember the same science teacher erecting blast shields before placing a small amount of sodium in a beacker of water. The sodium fizzed and hissed, dancing across the surface of the water (sodium actually seems to float). Probably producing hydrogen and sodium oxide. I didn't see a flame (supposedly indicative of burning hydrogen), but neither did I see a hydrogen flame when the pop test was performed.
  23. Thanks actually. I'm glad I'm actually getting recognition from some of the more senior members of this forum, even if they disagree with me. Well, if it is true that the YD period is caused by a decrease of heat moving towards the Northern Hemisphere, and the radiative, greenhouse and other forcings stay roughly the same, one would expect a higher concentration of heat in the Southern Hemisphere. Yes, that point is made. The hypothetical causes were actually quite interesting. Thanks for posting it up there. Okay. Roy Spencer... He's said this, it seems a little like a conspiracy theory: I'm just saying that although Spencer may make decent papers, he does seem significantly biased and that much of what he says should be taken with a pinch of salt. The amount of water vapour in the troposphere is considered a feedback for good reason. Naturally it maintains a state of equilibrium based on the temperature. This is because of its very short life in the atmosphere, around 10 days. So, over long periods of time, all other things being equal, the level of water vapour will stay much the same, save for short-term fluctuations. If you have an increase in temperature, you'll have an increase in water vapour in order to maintain the same relative level of humidity. This is a feedback, warming the atmosphere even more. Thus it's a feedback. Sure, this may a fairly superficial explanation, but I believe it's fairly close to the truth. As for clouds, I'm not exactly sure. There seems to be very little if any, external forcing influencing clouds. Cosmic Rays is one, but that has yet to be proven. We know that clouds are influenced by atmospheric conditions, so it seems logical that clouds could be considered a function of the atmospheric conditions. As they may have an affect on temperature, it seems fair that they're considered a feedback. Basically, although clouds and water vapour are important, they aren't the primary drivers of the climate. They play to the whims of the other greenhouse gases, because of their short life in the atmosphere. Yeah. I now realise it's important to look deeper into the issues so that you can make an educated decision. I can tell you the former would make an excellent paper. Remember you'd have to discount the proxies that don't work, and fail to correlate with the instrumental record. The latter, that would be interesting, but I doubt it'd be published as a paper, I'd like to see it as an intellectual exercise. Furthermore, I think that the Mann and Jones 2003 paper did include significant error bars. It doesn't appear as if they purport to have some ridiculous level of accuracy. I think I've found another link to the same paper, though it is in the same domain. Try this. That is a good point, would you mind telling me which ones were and weren't? I know that number 7, Mann and Jones 2004 is not. It definitely doesn't calibrate proxies with the global instrumental temperature record, it actually calibrates the proxies with the local temperature record. The paper says the following: Would you mind sourcing that claim about the Little Ice Age? It doesn't really show up on any of the graphs I'm seeing. And yes, I would expect the temperatures to rise to a normal level at the end of an Ice Age (say no higher than the MWP), as opposed to an unusually high level as we are experiencing now. On the subject of the Holocene Optimum, here is a rough statistical analysis of several proxies in different parts of the world (coloured lines) that provide information on temperatures reaching back to the end of the last ice age. The black line is an average of those temperatures. This provides a rough guide on the temperatures of the Holocene. Note that the temperatures have a resolution of about 300 years which as a result, doesn't actually show the current warming. This should serve to illustrate that the current temperature increases are actually rather drastic, in that they are occurring too fast for the graph to show. Additionally, it also illustrates that the Holocene Optimum wasn't actually warmer than the temperatures we're currently experiencing, at least on a global scale. You could actually argue that the temperatures were cooler during the Holocene Optimum using this graph, however, the resolution is too low to make a fair comparison. Although I'm the study is probably relatively sound, having only skimmed over it (I'm a little tired of reading through climate science research papers), I can't help object to the nature of the record. It only measures temperatures in the Swiss alps. The climate reconstructions are better measures of the global climate because that is actually what they measure. That's pretty good for a 1 am post. I believe that Swansont addressed most of those points. I would like you to name that proxy, and the study it was used in, so I can better address that claim. Additionally the reason he dropped the proxy data after 1980 was because it was wrong. The tree-ring data disagreed with the instrumental temperature record data. It's called the divergence problem. When you have data that is glaringly flawed, you probably should remove it. That is what they've done there.
  24. So you're accepting that the time-dialation predicted by Einstein's relativity as fact? See, the twin paradox doesn't have anything to do with how old the twins look, it's do with how old they are. The twins could be interchanged with clocks anything else and the result would still be the same. And why would a fast moving animal be affected by failing organs and a weaker immune system? If you want to understand relativity, I would highly recommend this book: Relativity Visualised. I'm not a scientist or anything, but Epstein really manages to explain the theory almost entirely without maths. I'm a secondary school student and this guy makes sense.
  25. I'm don't think that is entirely correct. I hadn't really realised this at first, but the Younger Dryas appears to be confined to the Northern Hemisphere. This article: What Caused the Younger Dryas Event, by Anders E. Carlson, published in Geology says the following: So while the Younger Dryas may have been greater in magnitude than the current warming we are seeing now it was actually more limited in terms of extent. Furthermore, there appears to be a prevailing theory among climate scientists. The same article goes on to say: I was referring to the cause of the Younger Dryas event when I stated that, sorry for the misunderstanding. It may be possible for that change to occur, but that doesn't actually mean it did. Secondly, I would like to see a source for that claim, as you have neglected to provide one. I understand I was wrong when I stated they were all global reconstructions in hindsight. The fact that one of these graphs may have been dubious doesn't invalidate all the other graphs. M.E. Mann and P.D. Jones (2003). , Geophysical Research Letters, 30(15): 1820. doi:10.1029/2003GL017814 is a global reconstruction using 13 different data sets. It alone should be reasonable evidence to suggest that the current warming is unprecedented at least in terms of the last two millennia. Sure. Then would you deny that increased emissions of GHGs would likely cause a warming effect on the climate? It's interesting that you are saying this. Mann and Jones at least in the aforementioned paper doesn't do actually do that. Here's a paragraph from their paper (emphasis mine): So Mann and Jones, actually take the proxy and compare it to the local instrumental record to see how accurate it is. Then they use that to weight their combinations to form the graph. I'd consider that pretty reasonable myself. That doesn't invalidate the paper I've mentioned earlier which is number 6 if you want to know. Number 7 is also global, as is number 8, and number 10 appears to be global as well. Okay, they do use the same proxies again and again, but they also include different proxies as well, so it's not entirely the same. Explain to me the relevance of those Tijander Sediments to this graph. And in what paper was this actually published? I would like to know. I understand that the Pines were used in a number of these graphs, but that doesn't invalidate the darkest blue data set, Jones 98, the lightest blue Briffa 2001, the red-orange Huang 2004 or the darkest red, Oerlemans 2005. It doesn't really appear to matter either way, whether they include Bristlecone Pine data or otherwise, they all appear to be giving the same message. Mann 2008 and 2009 are not included in that graph. I'm not even sure if those papers exist. Second of all, I'm pretty sure that not all reconstructions use Bristlecone Pine tree ring data, and yet they all seem to support each other. This article in the Guardian suggests that Mann's data although tainted in the 1999 reconstruction, was generally fairly accurate. And furthermore, those papers were published quite some time ago and I don't think they really can go back and change the data they used.
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