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Post by lsvalgaard on Jun 25, 2009 3:33:00 GMT
Dr. Svalgaard, In the last couple of days the temperature of the solar wind has dropped to the bottom of the scale, as shown on link below: www.swpc.noaa.gov/ace/MAG_SWEPAM_7d.htmlWhat is the significance of this? Thanks in advance. The temperature and the solar wind speed have dropped because there is not much magnetic field left in the solar atmosphere. Thiis will probably change over the following months.
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Post by france on Jun 29, 2009 10:36:28 GMT
more time temperature and speed of solar wind felt down and go up again today.
But I noticed that the two last coronal holes (one at HN and one at equatorial area) were nearly joined when the two solar sunspot (1022 and 1023) appeared together at equatorial belt (perhaps the orgin of the storms alert with class A eruptions). It seems to be still the case even if coronal holes are lower with disappearence of the solar sunspots.
Is this observation right or not Dr Svalgaard ?
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Post by lsvalgaard on Jun 29, 2009 12:48:09 GMT
more time temperature and speed of solar wind felt down and go up again today. But I noticed that the two last coronal holes (one at HN and one at equatorial area) were nearly joined when the two solar sunspot (1022 and 1023) appeared together at equatorial belt (perhaps the orgin of the storms alert with class A eruptions). It seems to be still the case even if coronal holes are lower with disappearence of the solar sunspots. Is this observation right or not Dr Svalgaard ? Active regions help feed magnetic field into coronal holes so sunspots and coronal holes are intimately linked.
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Post by brokenheadphonez on Jul 9, 2009 4:25:54 GMT
Hey there everyone!
I have a question for Dr. S:
Can we measure or estimate the amount of discharge of solar ejectae or the amount of ejectae that interacts with Earth's magnetosphere or both?
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Post by lsvalgaard on Jul 9, 2009 4:49:02 GMT
Hey there everyone! I have a question for Dr. S: Can we measure or estimate the amount of discharge of solar ejectae or the amount of ejectae that interacts with Earth's magnetosphere or both? yes, see the appendix in www.leif.org/research/Geomagnetic-Response-to-Solar-Wind.pdfalthough more than 35 years old, the conclusions of that paper still stands.
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Post by brokenheadphonez on Jul 9, 2009 15:03:01 GMT
Thanks doc, wow that is so retro! ;D
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Post by Ole Doc Sief on Jul 10, 2009 4:14:21 GMT
Hey there everyone! I have a question for Dr. S: Can we measure or estimate the amount of discharge of solar ejectae or the amount of ejectae that interacts with Earth's magnetosphere or both? yes, see the appendix in www.leif.org/research/Geomagnetic-Response-to-Solar-Wind.pdf although more than 35 years old, the conclusions of that paper still stands. At the bottom of page two of above 71 page paper, you state that "Activity never ceases completely and auroras can always be seen some where". What would have to happen to cause cessation of Auroras? During the worst of the Maunder Minimum there were still Auroras right?
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Post by lsvalgaard on Jul 10, 2009 5:44:59 GMT
At the bottom of page two of above 71 page paper, you state that "Activity never ceases completely and auroras can always be seen some where". What would have to happen to cause cessation of Auroras? During the worst of the Maunder Minimum there were still Auroras right? As long as there is a solar wind there will be aurora. And aurorae were seen during the Maunder Minimum in Europe. And in Iceland and Norway, where they see aurorae every day, then and now.
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Post by midtskogen on Jul 15, 2009 9:05:05 GMT
As long as there is a solar wind there will be aurora. And aurorae were seen during the Maunder Minimum in Europe. And in Iceland and Norway, where they see aurorae every day, then and now. A much quoted "fact" here in Norway is that Petter Dass (1647-1707), the foremost Norwegian poet in his time, does not mention the aurora supposedly because there wasn't any in his lifetime. Of course, a lack of mention doesn't prove anything, though it's curious since he lived near the arctic circle and did frequently describe nature, the polar night etc. Are there actual contemporary textual proofs that the aurora did exist during the Maunder minimum? Or could the lack of mention by the poet be explained if the geomagnetic pole was located elsewhere at that time making northern Norway much less suited for observations than today?
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Post by kerwin on Aug 10, 2009 20:13:19 GMT
Dr. S,
What effect if any would the shrinking of the atmosphere have on volcanic activity and/or atmospheric pressure here on earth. I was also wondering if it had any effect on gravity.
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Post by lsvalgaard on Aug 10, 2009 20:21:16 GMT
Dr. S, What effect if any would the shrinking of the atmosphere have on volcanic activity and/or atmospheric pressure here on earth. I was also wondering if it had any effect on gravity. The thickness of the upper [100 km and up] atmosphere is changing, but the pressure is given by the weight of all the air in a column from the surface to the 'top of the atmosphere' no matter how high that is, and that weight depends on the number of molecules which does not change, so no significant change in pressure or volcanoes from this.
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Post by radiant on Aug 12, 2009 10:53:24 GMT
Dr. S, What effect if any would the shrinking of the atmosphere have on volcanic activity and/or atmospheric pressure here on earth. I was also wondering if it had any effect on gravity. The thickness of the upper [100 km and up] atmosphere is changing, but the pressure is given by the weight of all the air in a column from the surface to the 'top of the atmosphere' no matter how high that is, and that weight depends on the number of molecules which does not change, so no significant change in pressure or volcanoes from this. Dr Svalgaard Some questions for you please 1. Do you have any information about the relative changes in partial pressures of the gases or the atmosphere with altitude following the changes in total atmospheric height? Air behaves much like water does in that it flows most freely where it is most densest at the lowest points on the ground and the denser masses of air do not like to climb obstructions so go around them. Following from that principal if the atmospheric heights change for the various densitities of the gases at altitude it is going to have a big influence on how air flows around the globe - i would expect anyway. 2. Is it conceivable that the air itself is very minutely magnetic in a way that is not measureable to humans and yet and can be influenced by changes in solar magnetism or other solar properties? Thanks
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Post by lsvalgaard on Aug 12, 2009 13:07:39 GMT
The thickness of the upper [100 km and up] atmosphere is changing, but the pressure is given by the weight of all the air in a column from the surface to the 'top of the atmosphere' no matter how high that is, and that weight depends on the number of molecules which does not change, so no significant change in pressure or volcanoes from this. Dr Svalgaard Some questions for you please 1. Do you have any information about the relative changes in partial pressures of the gases or the atmosphere with altitude following the changes in total atmospheric height? Air behaves much like water does in that it flows most freely where it is most densest at the lowest points on the ground and the denser masses of air do not like to climb obstructions so go around them. Following from that principal if the atmospheric heights change for the various densitities of the gases at altitude it is going to have a big influence on how air flows around the globe - i would expect anyway. 2. Is it conceivable that the air itself is very minutely magnetic in a way that is not measureable to humans and yet and can be influenced by changes in solar magnetism or other solar properties? 1: In the lower and dense atmosphere, the gases are well mixed [water vapor is a small exception]. At high altitudes that is not the case. But, since the density of the atmosphere decreases by a factor of 1000 for each 50 km you go up, it quickly becomes so low that it doesn't matter as far a pressure is concerned. 2: I don't think so.
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Post by radiant on Aug 12, 2009 15:52:37 GMT
Dr Svalgaard Some questions for you please 1. Do you have any information about the relative changes in partial pressures of the gases or the atmosphere with altitude following the changes in total atmospheric height? Air behaves much like water does in that it flows most freely where it is most densest at the lowest points on the ground and the denser masses of air do not like to climb obstructions so go around them. Following from that principal if the atmospheric heights change for the various densitities of the gases at altitude it is going to have a big influence on how air flows around the globe - i would expect anyway. 2. Is it conceivable that the air itself is very minutely magnetic in a way that is not measureable to humans and yet and can be influenced by changes in solar magnetism or other solar properties? 1: In the lower and dense atmosphere, the gases are well mixed [water vapor is a small exception]. At high altitudes that is not the case. But, since the density of the atmosphere decreases by a factor of 1000 for each 50 km you go up, it quickly becomes so low that it doesn't matter as far a pressure is concerned. 2: I don't think so. So if you lower the atmosphere by 200kms then the pressure at mountain height altitudes must change by a measureable amount i am assuming still? Pressure at sea level seems a combination of gravity and diffusion into the thinner atmosphere at higher altitudes so if you decrease the height of maximum diffusion will it not create changes all the way down?
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Post by lsvalgaard on Aug 12, 2009 16:23:46 GMT
1: In the lower and dense atmosphere, the gases are well mixed [water vapor is a small exception]. At high altitudes that is not the case. But, since the density of the atmosphere decreases by a factor of 1000 for each 50 km you go up, it quickly becomes so low that it doesn't matter as far a pressure is concerned. 2: I don't think so. So if you lower the atmosphere by 200kms then the pressure at mountain height altitudes must change by a measureable amount i am assuming still? Pressure at sea level seems a combination of gravity and diffusion into the thinner atmosphere at higher altitudes so if you decrease the height of maximum diffusion will it not create changes all the way down? The pressure is the weight of the overlying air. Next time you stand on a scale to check your weight, try to bend down in your knees and see how much your weight [your pressure on the scale] changes.
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