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Post by af4ex on Feb 9, 2011 16:16:10 GMT
@leif > Don't read too much into values on a single day. But wouldn't you agree that yesterday's M1.9 flare was pretty spectacular! That 17Ghz spike is enormous and we don't often see a strong correlation in the 34Ghz waveform. 1153 also had a strong C1.1 event earlier. And 1157 made some B-class noise at 0547Z (but NOAA somehow failed to attribute this to 1157, but it's very obvious in microwaves). The M-flare was recorded from a very oblique angle. Do you think the classification would have been larger if it had been in more direct view of the Earth (and GOES X-RAY)? Attachments:
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Post by lsvalgaard on Feb 9, 2011 16:36:18 GMT
@leif > Don't read too much into values on a single day. But wouldn't you agree that yesterday's M1.9 flare was pretty spectacular! That 17Ghz spike is enormous and we don't often see a strong correlation in the 34Ghz waveform. 1153 also had a strong C1.1 event earlier. And 1157 made some B-class noise at 0547Z (but NOAA somehow failed to attribute this to 1157, but it's very obvious in microwaves). The M-flare was recorded from a very oblique angle. Do you think the classification would have been larger if it had been in more direct view of the Earth (and GOES X-RAY)? The M flare was still 10-100 times smaller than the really big X-flares we have seen. Did you notice how small the geomagnetic response was? hirweb.nict.go.jp/dimages/magneka/20110209.html The angle does not make much difference as the corona is rather transparent to X-rays. |
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Post by af4ex on Feb 9, 2011 16:59:02 GMT
@leif > Did you notice how small the geomagnetic response was? > hirweb.nict.go.jp/dimages/magneka/20110209.html Yes, just a tiny 'blip'. I take it that we don't often see these. (I looked in vain to see this blip in the CDN and USGS waveforms, then realized I was looking on the wrong side of the Earth. Doh) Was that due mostly to EUV, e.g. 304A? I'm guessing the mechanism was that the EUV rays created a cloud of ions that somehow accelerated (or deaccelerated) to create a magnetic dynamo pulse. |
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Post by lsvalgaard on Feb 9, 2011 18:13:59 GMT
@leif > Did you notice how small the geomagnetic response was? > hirweb.nict.go.jp/dimages/magneka/20110209.html Yes, just a tiny 'blip'. I take it that we don't often see these. (I looked in vain to see this blip in the CDN and USGS waveforms, then realized I was looking on the wrong side of the Earth. Doh) Was that due mostly to EUV, e.g. 304A? I'm guessing the mechanism was that the EUV rays created a cloud of ions that somehow accelerated (or deaccelerated) to create a magnetic dynamo pulse. EUV and Xrays enhance the conductivity and therefore the dynamo generated current increases. For a large X-flare the blip might be up to 25 times larger, e.g. |
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Post by af4ex on Feb 9, 2011 18:28:43 GMT
@leif > Did you notice how small the geomagnetic response was? > hirweb.nict.go.jp/dimages/magneka/20110209.html Yes, just a tiny 'blip'. I take it that we don't often see these. (I looked in vain to see this blip in the CDN and USGS waveforms, then realized I was looking on the wrong side of the Earth. Doh) Was that due mostly to EUV, e.g. 304A? I'm guessing the mechanism was that the EUV rays created a cloud of ions that somehow accelerated (or deaccelerated) to create a magnetic dynamo pulse. EUV and Xrays enhance the conductivity and therefore the dynamo generated current increases. For a large X-flare the blip might be up to 25 times larger, e.g. Ok, that explains why the blips are all positive, the enhanced conductivity merely increases the dynamo current that is already flowing and generates more geomagnetism. Thanks |
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Post by af4ex on Feb 9, 2011 18:58:09 GMT
Right now the SFI is 90 and SN is 71, higher than it's been for a while. But a casual glance at the Sun, even through a small telescope, still leaves the impression of a 'spotless' Sun. The current conjecture is that we're entering another Maunder Minimum (which will be called the 'Eddy Minimum'). It is popularly believed that there were virtually no sunspots during the M.M. (1645-1715) But perhaps it was more of a case, like today, of under-observation, rather than the lack of spots. And also likely that the L&P effect had something to do with decline of spots then, as now. Attachments:
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Post by lsvalgaard on Feb 9, 2011 19:27:57 GMT
Right now the SFI is 90 and SN is 71, higher than it's been for a while. But a casual glance at the Sun, even through a small telescope, still leaves the impression of a 'spotless' Sun. The current conjecture is that we're entering another Maunder Minimum (which will be called the 'Eddy Minimum'). It is popularly believed that there were virtually no sunspots during the M.M. (1645-1715) But perhaps it was more of a case, like today, of under-observation, rather than the lack of spots. And also likely that the L&P effect had something to do with decline of spots then, as now. be careful with the term 'under-observation'. It smacks of people NOT even looking and during the M.M. as now they were [are] looking hard. Now, you can't count what you can't see, so if visibility of spots is impaired you see less spots even though activity may still be there. |
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Post by af4ex on Feb 9, 2011 20:23:27 GMT
be careful with the term 'under-observation'. It smacks of people NOT even looking and during the M.M. as now they were [are] looking hard. Now, you can't count what you can't see, so if visibility of spots is impaired you see less spots even though activity may still be there. I understand your concern, and I certainly don't want to revise history. But my notion was that perhaps observers were less motivated to 'look hard' when spots were sparse. Perhaps they would hold a piece of smoked glass to their eye and say: "I don't see anything, so I won't bother looking in the telescope today, and will just write 'no spots' in my journal" etc. Is there historical evidence that the 'official' observations were just as thorough in the Maunder period as before and after? If so, I stand corrected. |
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Post by af4ex on Feb 9, 2011 21:08:48 GMT
FYI, the noon solar flux reading from Penticton has been posted: 89.
So looks like activity will be heading down, again.
Penticton 1700Z, 2000Z, 2300Z:
2011 Feb 2 2800 79 79 79
2011 Feb 3 2800 80 80 80
2011 Feb 4 2800 81 82 81
2011 Feb 5 2800 81 81 80
2011 Feb 6 2800 80 80 80
2011 Feb 7 2800 82 82 82
2011 Feb 8 2800 91 90 91
2011 Feb 9 2800 90 89 --
:-\
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Post by af4ex on Feb 9, 2011 22:31:09 GMT
I said:
> Is there historical evidence that the 'official' observations
> were just as thorough in the Maunder period as before
> and after? If so, I stand corrected.
[Answering my own question] Yes, of course, considering that some of the greatest astronomers of all times lived in the Maunder era: Cassini, Halley, Hooke, Huyghens, Roemer etc. All meticulous observers, any one of whom would have easily falsified such a lazy notion as I stated.
Sorry for quibbling over your response to that issue, Leif.
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Post by lsvalgaard on Feb 9, 2011 23:18:24 GMT
be careful with the term 'under-observation'. It smacks of people NOT even looking and during the M.M. as now they were [are] looking hard. Now, you can't count what you can't see, so if visibility of spots is impaired you see less spots even though activity may still be there. I understand your concern, and I certainly don't want to revise history. But my notion was that perhaps observers were less motivated to 'look hard' when spots were sparse. Perhaps they would hold a piece of smoked glass to their eye and say: "I don't see anything, so I won't bother looking in the telescope today, and will just write 'no spots' in my journal" etc. Is there historical evidence that the 'official' observations were just as thorough in the Maunder period as before and after? If so, I stand corrected. yes there is: www.leif.org/EOS/94GL01698.pdf |
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Post by Bob k6tr on Feb 9, 2011 23:35:51 GMT
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