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Post by william on Oct 17, 2008 3:40:33 GMT
There is new data that show the glacial/interglacial cycles start and end abruptly. The question which everyone is trying to understand is what is the forcing mechanism. Kaplan et al's recent finding that both Northern and Southern Hemisphere simultaneous warmed and cooled which disproves the ocean forcing function and contradicts the Milankovitch orbit forcing hypothesis. www.nsf.gov/news/news_summ.js...100348&org=ATM"The results address a major debate in the scientific community, according to Singer and Kaplan, because they seem to undermine a widely held idea that global redistribution of heat through the oceans is the primary mechanism that drove major climate shifts of the past." "The implications of the new work, say the authors of the study, support a different hypothesis: that rapid cooling of the Earth's atmosphere synchronized climate change around the globe during each of the last two glacial epochs." "Because the Earth is oriented in space in such a way that the hemispheres are out of phase in terms of the amount of solar radiation they receive, it is surprising to find that the climate in the Southern Hemisphere cooled off repeatedly during a period when it received its largest dose of solar radiation," says Singer. "Moreover, this rapid synchronization of atmospheric temperature between the polar hemispheres appears to have occurred during both of the last major ice ages that gripped the Earth." This paper discusses a possible forcing mechanism that could affect both hemispheres simultaneously. arxiv.org/abs/physics/0407005“The Glacial Cycles and Cosmic Rays” by J. Kirkby, A. Mangini, and R. Muller Richard Muller is a specialist in paleo climatology and was one of the first to find specific evidence that disproved Milankovitch's mechanism and theory. "The cause of the glacial cycles remains a mystery. The origin is widely accepted to be astronomical since paleoclimatic archives contain strong spectral components that match the frequencies of Earth’s orbital modulation. Milankovitch insolation theory contains similar frequencies and has become established as the standard model of the glacial cycles. However, high precision paleoclimatic data have revealed serious discrepancies with the Milankovitch model that fundamentally challenge its validity and re-open the question of what causes the glacial cycles."
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Post by twawki on Oct 17, 2008 11:47:48 GMT
I only read the except of the paper but as I understand it ;
reduced solar = more clouds = lower temps = ice age triggers
How do the ice ages correlate with solar cycles?
Theres a similiar one here;
Sunspots => Solar Flares => Magnetic Field Shift => Shifting Ocean and Jet Stream Currents => Extreme Weather and Human Disruption (mitch battros)
All interesting stuff
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Post by Acolyte on Oct 17, 2008 13:06:54 GMT
Regarding the glacial cycles...
There exists a problem with Precession of the Equinoxes. Precession is commonly linked to things like the Milankovic cycles & is normally thought to be the product of Lunar & solar effrects on the Earth.
More recently these effects have been shown to be not accurate & there's been a few attempts to add in extra sources to account for the rate of Precession.
But, as stated, there is a problem. Earth's actual orbit doesn't show precession even though, from the surface of Earth, Precession is fairly obvious.
Take the Perseids - every year, around August 12th, (with slight regular modification adjusted for each leap year) the earth sweeps through the Perseid meteor shower. The Perseids are as regular as clockwork & have been since the ancient Chinese noted them.
And they shouldn't be!
If the Precession of the Equinox is caused by the moon & the sun acting on the oblateness of Earth, the Precession should also affect the date on which Earth encounters the Perseids - and it doesn't!
So Precession is caused by something else. If the Glacial cycles are linked to Precession then we need to understand just what caused Precession - at which point we can begin to work out the cycle of Glacial events.
And if Precession is incorrect as currently thought to be, then Obliquity & even orbit shape may have a different value and effect. Milankovic cycles depend, if memory serves, to a large extent on Precession.
Note I am not saying Precession does not exist, just that the popularly believed explantion for it may not reflect an accurate position on what Precession really is.
And it's another reason why climate models can't reflect real climate.
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Post by Belushi TD on Oct 17, 2008 17:56:26 GMT
Hmmm... Correct me if I'm wrong, but doesn't the precession of the equinoxes happen on a 25,700 year cycle? At least, according to WIKI. Anyway... 25,700 years means 20 minutes a day, again according to WIKI.
My understanding is that the Persieds actually PEAK around August 12, but actually happen for up to a week on either side. Note that says AROUND, not ON. I would think that there is significant wiggle room there. We've only had a truely dependable calendar for the last, what, 1500 years? I would like to suggest that since it takes 72 years for a day to precess (24 hours * 60 min/hr / 20 minutes), and that the meteor shower is not a specifically timed event, that the Perseids is probably NOT a good means of showing problems with the precession of the equinoxes. 1500 years means 20 days. There have been CORRECTIONS in the calendars that were more than 20 days. The switch from Julian to Gregorian "lost" 12 days (look up George Washington's birthday. He was born before the change, and there was considerable confusion as to which day to celebrate his birthday at one time).
Before you jump on me about this, I KNOW that we have a pretty good idea as to when and the magnitude of these corrections. However, how sure are we that the astronomers in question knew exactly what they needed to do to figure it out?
Belushi TD
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Post by Acolyte on Oct 17, 2008 23:24:24 GMT
Hmmm... Correct me if I'm wrong, but doesn't the precession of the equinoxes happen on a 25,700 year cycle? At least, according to WIKI. Anyway... 25,700 years means 20 minutes a day, again according to WIKI... ...Before you jump on me about this, I KNOW that we have a pretty good idea as to when and the magnitude of these corrections. However, how sure are we that the astronomers in question knew exactly what they needed to do to figure it out? Belushi TD Not planning on any jumping. ;D And the sheer number of corrections that have been needed are an indication we're kluding up an answer for Precession. Also it seems clear, unless we ridicule the abilities of earlier astronomers in performing measurements, the rate of precession is altering - it's slightly less now than it was 100 years back & less than when Newton proposed it to be due to gravitational influences of moon & sun on the oblateness of Earth. Precession was something I ran into years back & I accepted the explanations for it that I read then. More recently however I've been trying to get my head around Walter Cruttenden's book 'Lost star of Time & Space' - someone I respect wanted to know how true it might be. It is a disturbing theory - I'm not talking here about his idea that the precession cycle affects growth & decay in human civilisations, but rather the actual astronomy side of things. That 20 minutes comes up a few times; and it isn't findable in some others - when comparing solar cycles like Earth day & year with sidereal cycles, there seems to be discrepancies, that should not be there if the standard theory is correct. For example, the 20 minutes means the length of the day should be 3.3 seconds less than we know, through ever-increasingly accurate measurements, it is. 3.3 seconds in something as thoroughly measured as our day is a glaring error. Where it applies here is in the changing cycles that I've seen used as cause for the altering patterns of climate on Earth. If precession is not attributable to Earth wobble, then it seems to reduce the amount of wobble available to explain changes in climate patterns. After all, we look at the wobble by using the precessional measurements - if they have a different explanation, I don't know of much other evidence that the wobble is occurring at all. I started a bit sceptical, but now, about halfway through the book, I must admit, Cruttenden is making his case. And to be honest, his cycles of growth in human affairs kind of fits with other stuff I've learned along the way. But that's a separate subject to Global warming & cycles that may affect our climate.
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Post by Belushi TD on Oct 18, 2008 6:20:15 GMT
Hey Acolyte.
Two things... The "don't jump on me" was aimed at the general population, not you personally. Second, I was trying to show that the meteor showers are probably NOT a good means of showing the precession is not what we think it is.
Also... Isn't the precession going in the opposite direction as the spin of the earth? It seems to me that the precession shouldn't affect the length of the day. But I also feel like Calvin from Calvin and Hobbes when his father shows him how the outside edge of a record goes faster than a point partway in, and the center shouldn't move at all. I KNOW there something I'm not getting, but I can't grasp what it is.
Belushi TD
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Post by Acolyte on Oct 18, 2008 10:33:02 GMT
Hey Acolyte. Two things... The "don't jump on me" was aimed at the general population, not you personally. Second, I was trying to show that the meteor showers are probably NOT a good means of showing the precession is not what we think it is. Also... Isn't the precession going in the opposite direction as the spin of the earth? It seems to me that the precession shouldn't affect the length of the day. But I also feel like Calvin from Calvin and Hobbes when his father shows him how the outside edge of a record goes faster than a point partway in, and the center shouldn't move at all. I KNOW there something I'm not getting, but I can't grasp what it is. Belushi TD The 'jumping' comment was meant to reassure you - it can be difficult on the web sometimes to know when someone is offended or anxious. S'all good. OK, I'll try my best... Keep in mind I'm working my way through to an understanding of what's going on so I can get a picture I can relate to about how the orbits work etc. any errors in explanation are mine, not Cruttenden's. If there is such a thing as precession & if it is locally caused (ie. it's Earth precession within th Solar System frame of reference) we have a problem with the year - the length of the year as measured by the Earth going round the sun, as measured against the sun, should be the same length as the the length of the year as measured by the Earth going round the sun, as measured against the fixed stars. The problem is they aren't, which implies that the precession effect isn't local - ie. that Earth is not precessing in relation to the solar system but that the solar system precesses in relation to the galaxy. There's also a problem I saw being looked at years back in Scientific American relating to the angular momentum of the solar system. 99% of the mass of the system is in the sun but 99% of the angular momentum is in the planets. This hasn't yet been resolved except by suggestions of extra mass somewhere 'out there' to take into account the apparent loss of angular momentum, something theory says can't occur. Now IF precession is caused by the wobbling of Earth's axis, (& keep in mind that as far as I know we don't actually have confirmation that is does wobble except for the measurement of precession) then the rotation of Earth needs to be slightly different to the 24 hour day to account for that 20 minutes per year of precession. Keep in mind the precession effect is supposed to be an earthly view of things being altered due to the wobble. But the day on Earth doesn't change - we'd know about it - and the year does. The Perseids and other events like the Venus transits prove that Earth is not slipping in orbit with respect to the rest of the solar system, so the lunar & solar version of precession is invalid. Those events happen as regular as clockwork & that 20 minutes per year, across 100 year is about 33 hours - we'd know if Earth had somehow altered it's orbital timing by 33 hours. Also, unless there's something new being added to the lunar/solar explanation, there's something screwy as well on the rate of precession - it is changing. The number of years required for precession to move a constellation 1º back around the orbit is decreasing. That requires a whole new set of explanations & I haven't seen any yet. So when you work through the evidence, what we have is a proposal by Newton for an explanation, followed by several centuries of people with better measurements trying to make that explanation fit the facts. But we now know more & taking a look at some of the orbital implications makes it clear it's not Pisces causing that fishy smell. On the other hand, presuming the Solar System is precessing explains nearly all the data - leaving only the question... around what precisely could the solar system be precessing? Precession is an orbital phenomena so to accept the Solar System exhibits it is to propose the system itself is in an orbit. Now this isn't all as off kilter as it might seem - recent star searches have shown that it is very likely the Solar System is not native to the Milky Way. Not only are the remnants of the Sagittarius galaxy (cluster?) positioned appropriately, it would help explain just why the Solar System equatorial plane is at an angle to the Milky Way equatorial plane. So if we have come from elsewhere, we may be looking at the neoighbouring space a little incorrectly - it might be feasible for example to view the regular ELE's (Extinction Level Events) as things occurring due to the system passing through the plane of the galaxy rather than requiring something more esoteric. (we'd pass through fairly regularly as the 'bouncing' motion of the system settled down towards leaving us captured by the Milky Way. Note the last paragraph is my speculation only - it's not something Cruttenden nor anyone else has written.
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Post by tilmari on Oct 18, 2008 15:56:23 GMT
Hmmm... Correct me if I'm wrong, but doesn't the precession of the equinoxes happen on a 25,700 year cycle? At least, according to WIKI. Anyway... 25,700 years means 20 minutes a day, again according to WIKI. My understanding is that the Persieds actually PEAK around August 12, but actually happen for up to a week on either side. Note that says AROUND, not ON. I would think that there is significant wiggle room there. We've only had a truely dependable calendar for the last, what, 1500 years? I would like to suggest that since it takes 72 years for a day to precess (24 hours * 60 min/hr / 20 minutes), and that the meteor shower is not a specifically timed event, that the Perseids is probably NOT a good means of showing problems with the precession of the equinoxes. 1500 years means 20 days. There have been CORRECTIONS in the calendars that were more than 20 days. The switch from Julian to Gregorian "lost" 12 days (look up George Washington's birthday. He was born before the change, and there was considerable confusion as to which day to celebrate his birthday at one time). Before you jump on me about this, I KNOW that we have a pretty good idea as to when and the magnitude of these corrections. However, how sure are we that the astronomers in question knew exactly what they needed to do to figure it out? Belushi TD 25700 years means according to my reckonings only 1.2 minutes per year. 1 degree amounts thus in 71.4 years. Which means for example that we have so called "reliable" temperature observations from a little over a time when the Earth has recessed about 2 degrees or 1.1 % of the half-circle of the precession. Timo
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Post by Acolyte on Oct 18, 2008 23:11:34 GMT
Hmmm... Correct me if I'm wrong, but doesn't the precession of the equinoxes happen on a 25,700 year cycle? At least, according to WIKI. Anyway... 25,700 years means 20 minutes a day, again according to WIKI. My understanding is that the Persieds actually PEAK around August 12, but actually happen for up to a week on either side. Note that says AROUND, not ON. I would think that there is significant wiggle room there. We've only had a truely dependable calendar for the last, what, 1500 years? I would like to suggest that since it takes 72 years for a day to precess (24 hours * 60 min/hr / 20 minutes), and that the meteor shower is not a specifically timed event, that the Perseids is probably NOT a good means of showing problems with the precession of the equinoxes. 1500 years means 20 days. There have been CORRECTIONS in the calendars that were more than 20 days. The switch from Julian to Gregorian "lost" 12 days (look up George Washington's birthday. He was born before the change, and there was considerable confusion as to which day to celebrate his birthday at one time). Before you jump on me about this, I KNOW that we have a pretty good idea as to when and the magnitude of these corrections. However, how sure are we that the astronomers in question knew exactly what they needed to do to figure it out? Belushi TD 25700 years means according to my reckonings only 1.2 minutes per year. 1 degree amounts thus in 71.4 years. Which means for example that we have so called "reliable" temperature observations from a little over a time when the Earth has recessed about 2 degrees or 1.1 % of the half-circle of the precession. Timo They'd be different minutes - Belushi is talking time where Tilmari is talking degrees. If we don't massage to data to fit a particular view, we have fairly decent data records going back considerably more than the time since we invented thermometers. If the proxies aren't pushed into little strait-jackets for the benefit of the agw (I read dopeydog's pos ;D ) they can tell us quite a bit about what Earth has been through. Particularly if we start to use them properly & cross reference them where they overlap & start doing some real science to find out why they vary. Of course that would require the archiving of the datasets currently hidden away from inquisitive eyes by the agw proponents so ALL interested parties can get a look at the original data.
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Post by tilmari on Oct 20, 2008 5:08:30 GMT
25700 years means according to my reckonings only 1.2 minutes per year. 1 degree amounts thus in 71.4 years. Which means for example that we have so called "reliable" temperature observations from a little over a time when the Earth has recessed about 2 degrees or 1.1 % of the half-circle of the precession. Timo They'd be different minutes - Belushi is talking time where Tilmari is talking degrees. If we don't massage to data to fit a particular view, we have fairly decent data records going back considerably more than the time since we invented thermometers. If the proxies aren't pushed into little strait-jackets for the benefit of the agw (I read dopeydog's pos ;D ) they can tell us quite a bit about what Earth has been through. Particularly if we start to use them properly & cross reference them where they overlap & start doing some real science to find out why they vary. Of course that would require the archiving of the datasets currently hidden away from inquisitive eyes by the agw proponents so ALL interested parties can get a look at the original data. This led my thoughts to a really interesting thing to study. The half-circle of precession is 12850 years, which means that if we take only precession into account, our climate is precisely opposite to that it was when the Younger Dryas began. And the Younger Dryas cold period ended 11700 years ago and with it the great Ice Age that began about 110,000 years ago. Timo
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Post by Acolyte on Oct 20, 2008 5:24:09 GMT
This led my thoughts to a really interesting thing to study. The half-circle of precession is 12850 years, which means that if we take only precession into account, our climate is precisely opposite to that it was when the Younger Dryas began. And the Younger Dryas cold period ended 11700 years ago and with it the great Ice Age that began about 110,000 years ago. Timo It's partly why I'm reading the Cruttenden book - the possible effect on Milankovic cycles if we have the reasons for Precession incorrect, the possible influences on the solar system climate, etc. There's one heck of a lot of unusual things going on right now... It seems like it might be a time of paradigm shift in how we view things - they normally come along when there's a build up of strangeness according to the 'old' way of things & people get to wondering why. Then again, maybe God just doesn't like Al Gore.
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Post by tilmari on Oct 20, 2008 7:41:26 GMT
There is new data that show the glacial/interglacial cycles start and end abruptly. The question which everyone is trying to understand is what is the forcing mechanism. Kaplan et al's recent finding that both Northern and Southern Hemisphere simultaneous warmed and cooled which disproves the ocean forcing function and contradicts the Milankovitch orbit forcing hypothesis. <snip> "The cause of the glacial cycles remains a mystery. The origin is widely accepted to be astronomical since paleoclimatic archives contain strong spectral components that match the frequencies of Earth’s orbital modulation. Milankovitch insolation theory contains similar frequencies and has become established as the standard model of the glacial cycles. However, high precision paleoclimatic data have revealed serious discrepancies with the Milankovitch model that fundamentally challenge its validity and re-open the question of what causes the glacial cycles." One needs very profound and complicated calculations to count the Milankowitch cycles together with non-Milankowitch forcings. Of the three Mila-cycles I consider only one, the 100,000 year cycle in dispute. But only together with Dansgaard-Oeschger cycles plus Heinrich events can we get a more clear picture and as far as I have made calculations the two lesser Mila-cycles are valid. I continue counting but the data is sparse and new data is continually popping up, so the picture has been in a constant refinement.
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Post by trbixler on Oct 21, 2008 4:55:52 GMT
Of course that would require the archiving of the datasets currently hidden away from inquisitive eyes by the agw proponents so ALL interested parties can get a look at the original data. You mention an issue that needs to be addressed in the scientific community. Data and programs need to be properly archived with full version control. Who, What, Where ,Why and When need to be noted in the version archive. In the programming world it is the only way to survive. It is unbelievable that there is no standard in place. At Climate Audit it is a daily effort of Steve to reconstruct data and programs. What a waste of valuable talent.
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Post by twawki on Oct 21, 2008 23:28:26 GMT
Of course that would require the archiving of the datasets currently hidden away from inquisitive eyes by the agw proponents so ALL interested parties can get a look at the original data. You mention an issue that needs to be addressed in the scientific community. Data and programs need to be properly archived with full version control. Who, What, Where ,Why and When need to be noted in the version archive. In the programming world it is the only way to survive. It is unbelievable that there is no standard in place. At Climate Audit it is a daily effort of Steve to reconstruct data and programs. What a waste of valuable talent. Well his talent could be used better in research but certainly not wasted pulling apart the shenanigans of the AGW movement. Though a code/standard is well overdue - be good to keep the 'b*st*ards' honest.
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Post by magellan on Oct 22, 2008 2:26:17 GMT
NCDC temperature monthly anomalies for Northern Hemisphere: January 2008: +0.10°C February 2008: +0.43°C March 2008: +1.03°C April 2008: +0.51°C May 2008: +0.53°C June 2008: +0.59°C July 2008: +0.55°C Brrr that's cold That's if you want to believe numbers coming from near surface stations.
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