Mobius Posted October 3, 2005 Share Posted October 3, 2005 Just thought I'd get your thoughts on this. Is the earth overall losing energy. It loses energy from tides, however the earth-moon system remains at constant energy. Our magnetic field is losing energy. Are we losing energy in our rotation? We gain energy from the sun but is the loss of this heat energy more or less than our gain....? All responses welcome Link to comment Share on other sites More sharing options...
swansont Posted October 3, 2005 Share Posted October 3, 2005 Just thought I'd get your thoughts on this.Is the earth overall losing energy. It loses energy from tides' date=' however the earth-moon system remains at constant energy. Our magnetic field is losing energy. Are we losing energy in our rotation? We gain energy from the sun but is the loss of this heat energy more or less than our gain....? All responses welcome[/quote'] The rotation slowdown is going into the moon, caused by the tidal friction you mentioned. The thermal energy is not currently in balance, according to this report and many others. ( Here is a more recent article) A little thing called global warming. Perhaps you've overheard it being mentioned. Link to comment Share on other sites More sharing options...
J.C.MacSwell Posted October 3, 2005 Share Posted October 3, 2005 Just thought I'd get your thoughts on this.Is the earth overall losing energy. It loses energy from tides' date=' however the earth-moon system remains at constant energy. Our magnetic field is losing energy. Are we losing energy in our rotation? We gain energy from the sun but is the loss of this heat energy more or less than our gain....? All responses welcome[/quote'] I would say yes, we are losing rotational and nuclear (or mass all meteorites aside). So we output more heat than we receive from the sun (though certainly at higher entropy) Link to comment Share on other sites More sharing options...
Mobius Posted October 3, 2005 Author Share Posted October 3, 2005 So it would seem from the global warming that we receive more energy from the sun then we re-radiate back into space. So the moon is taking energy from us due to tidal forces. Our magnetic field is losing energy. What about the using ouf our natural resources. If all the energy is converted without escaping into space then the overall energy loss is nill??? therefore nuclear energy and burning of fossil fuels should not effect the earths energy. I am really trying to find out if the world is losing energy overall. Maybe because of the 2nd law Thermodynamics, it is a must that we are losing energy... Also does the internal heat energy of the earth eventually escape the atmosphere?? I know loads of questions.... Link to comment Share on other sites More sharing options...
J.C.MacSwell Posted October 3, 2005 Share Posted October 3, 2005 The rotation slowdown is going into the moon' date=' caused by the tidal friction you mentioned. The thermal energy is not currently in balance, according to this report and many others. ( Here is a more recent article) A little thing called global warming. Perhaps you've overheard it being mentioned. Is the moon speeding up (decaying orbit) or slowing down? Link to comment Share on other sites More sharing options...
J.C.MacSwell Posted October 3, 2005 Share Posted October 3, 2005 So it would seem from the global warming that we receive more energy from the sun then we re-radiate back into space. So the moon is taking energy from us due to tidal forces. Our magnetic field is losing energy. What about the using ouf our natural resources. If all the energy is converted without escaping into space then the overall energy loss is nill??? therefore nuclear energy and burning of fossil fuels should not effect the earths energy. I am really trying to find out if the world is losing energy overall. Maybe because of the 2nd law Thermodynamics' date=' it is a must that we are losing energy... Also does the internal heat energy of the earth eventually escape the atmosphere?? I know loads of questions....[/quote'] We need a good accountant. LOL ther are many debits and credits. Is the global warming greater than our own nuclear output and fossil fuel use? I know they are not the direct cause, they "insulate" due to increased carbon dioxide etc. Link to comment Share on other sites More sharing options...
swansont Posted October 3, 2005 Share Posted October 3, 2005 Is the moon speeding up (decaying orbit) or slowing down? Slowing down. Of course this means it's increasing in total energy - receding at about 4 cm/year, currently. (This may seem counterintuitive to some - the kinetic energy is getting smaller, but the potential energy, which is negative, is getting smaller in magnitude at ~twice the rate. If you solve for KE+PE assuming a circular orbit it is easy to see what's going on) Link to comment Share on other sites More sharing options...
Mobius Posted October 3, 2005 Author Share Posted October 3, 2005 OK, so the moon is slowing down and getting further away from the earth all the time. So back to the original question: I am really trying to find out if the world is losing energy overall??? And the questions I raised in the 4th post! Link to comment Share on other sites More sharing options...
J.C.MacSwell Posted October 3, 2005 Share Posted October 3, 2005 Slowing down. Of course this means it's increasing in total energy - receding at about 4 cm/year, currently. (This may seem counterintuitive to some - the kinetic energy is getting smaller, but the potential energy, which is negative, is getting smaller in magnitude at ~twice the rate. If you solve for KE+PE assuming a circular orbit it is easy to see what's going on) Makes sense. Same idea as the drag on a satellite making it speed up (as long as it stays in orbit). The friction losses from the tides etc. create heat which dissipates or is stored as thermal gain and the "efficient" part of the equation is stored as PE gain which is augmented by an equal PE gain from the loss of KE from the moon/Earth orbit. All paid for by a longer day! Link to comment Share on other sites More sharing options...
J.C.MacSwell Posted October 3, 2005 Share Posted October 3, 2005 OK' date=' so the moon is slowing down and getting further away from the earth all the time. So back to the original question: I am really trying to find out if the world is losing energy overall??? And the questions I raised in the 4th post![/quote'] My guesstimate is still overall losing. It would be more clear cut if we were not currently in a net heat gain/nonequilibrium.(for the surface) The 2nd law of thermodynamics is no guarantee though as most of our energy comes from the sun (which definitely is losing) Link to comment Share on other sites More sharing options...
swansont Posted October 3, 2005 Share Posted October 3, 2005 Makes sense. Same idea as the drag on a satellite making it speed up (as long as it stays in orbit). The friction losses from the tides etc. create heat which dissipates or is stored as thermal gain and the "efficient" part of the equation is stored as PE gain which is augmented by an equal PE gain from the loss of KE from the moon/Earth orbit. All paid for by a longer day! Yes. Enjoy your leap second this Dec 31 from 23:59:59-23:59:60 UTC. Link to comment Share on other sites More sharing options...
J.C.MacSwell Posted October 4, 2005 Share Posted October 4, 2005 Yes. Enjoy your leap second this Dec 31 from 23:59:59-23:59:60 UTC. I will use it to sleep in! (and some people claim there is no God!) Link to comment Share on other sites More sharing options...
Mobius Posted October 4, 2005 Author Share Posted October 4, 2005 Well, I didn't think this thread would turn into a discussion on the eath-moon orbital decay, my fault probably for mentioning it in the original post. It does seem that the question of the earth losing energy was a bit more subtle than I had originally anticipated.... Link to comment Share on other sites More sharing options...
swansont Posted October 4, 2005 Share Posted October 4, 2005 I will use it to sleep in! (and some people claim there is no God!) Given that you're online around now, you'll probably be awake for it. Link to comment Share on other sites More sharing options...
J.C.MacSwell Posted October 4, 2005 Share Posted October 4, 2005 Given that you're online around now[/b'], you'll probably be awake for it. Your now was posted at only 9:32 PM (Nova Scotia/Atlantic time) Probably will stay up for the New Year though Link to comment Share on other sites More sharing options...
swansont Posted October 4, 2005 Share Posted October 4, 2005 Your now was posted at only 9:32 PM (Nova Scotia/Atlantic time) Probably will stay up for the New Year though And midnight UTC is 7PM Eastern standard time, and 8PM Atlantic. I'm almost certain that's when the leap second gets added. (Comments from colleagues that have to work on New Year's Eve to add the second saying at least the job is over at around 7, and the fact that you wouldn't want clocks 1 sec out of step anyway - it'd be a massive synchronization headache) Link to comment Share on other sites More sharing options...
lxxvii24 Posted October 4, 2005 Share Posted October 4, 2005 hw can u say say we put out more energy than the sun, do u mean to tell me that the net entropy for earth is more than that of the sun. Brother i think that is wrong estimation, the sun is still putting out enough energy. Concerning the fact whether or not we are losing energy i think there is a balance of some sought , i cant really lay hands on it. but the effect could be seen with us creating more green house gases and the earth getting warmer. Note i said our gases + sun's energy which proves too much... Link to comment Share on other sites More sharing options...
lxxvii24 Posted October 4, 2005 Share Posted October 4, 2005 Is the moon speeding up (decaying orbit) or slowing down? i think we are gradually losing the moon. centripetal forces, i guess Link to comment Share on other sites More sharing options...
mezarashi Posted October 4, 2005 Share Posted October 4, 2005 Just thought I'd get your thoughts on this.Is the earth overall losing energy. All responses welcome I think it's not really important to say whether the Earth is losing energy in total or not' date=' but rather if the energy we need for our race's survival and our planet's survival is being lost. It wouldn't make much sense to convert our kinetic rotational energy into a ball of fire so we can all burn and die miserably is it? And freeze to the death on the other side. hw can u say say we put out more energy than the sun, I didn't see this being mentioned. It may be contreversial however about whether we are emitting more radiation back into space than we are receiving from space (the sun mainly), but the greenhouse theory would probably say otherwise. do u mean to tell me that the net entropy for earth is more than that of the sun. I've never heard of the relationship between a system's entropy and its ability to put out energy. This may be an indirect deduction I don't know of. It'd be great clarification. Link to comment Share on other sites More sharing options...
J.C.MacSwell Posted October 4, 2005 Share Posted October 4, 2005 In thermal equilibrium and no other sources/storages of energy(not exactly the case but close approximation), we would be taking low entropy energy from the sun and outputing an equal amount of higher entropy energy into space. I guess that makes us a big (junk quality) photon producing machine! Link to comment Share on other sites More sharing options...
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