A collection of posts regarding glacial cycles.
- Towards an Understanding of Ice Ages
- The Milankovitch Puzzle
- Ice Age insights
- Phenomenology of Ice Ages
- Does Gaia end Ice Ages?
- When is the next Ice Age due ?(1)
- When is the next Ice Age due ? (2)
- Does the Moon trigger interglacials?
- Ice Ages – still a mystery
- The straw that broke the camel’s back
- The Moon’s eccentric orbit
- Lunar madness
- Tidal variations
- A challenge for climate models
- What causes interglacials? Part 1.
- Part 2: The real cause of Ice Ages ? – Resonant dust clouds ?
- Ice Ages revisited
- Evidence of variations in solar irradiance with Earth’s orbit
- Changes to Climate
- Does the moon trigger interglacials?
- Lunar Madness
- Tidal effects in Polar regions
I am a physicist with a background in statistics and spectral analysis. I have long been interested in climate “cycles” and I have come to the conclusion that, for the most part, we are actually dealing with red or pink noise. This is particularly true of the 100,000 year eccentricity eccentricity “cycle”. I believe the ice age “cycles” are band-limited red noise with small coherent signals at the obliquity and precession frequencies.
See my blog http://blackjay.net and the pages “Pause for Thought” and “Bounded Random Walk”.
See my latest post at http://http://blackjay.net/?page_id=93
Beryllium 10 is produced in the stratosphere by collision of cosmic rays with atmospheric particles. Its production rate is therefore controlled by the primary cosmic ray intensity, by solar modulation and by geomagnetic modulation, all of which processes lie outside of the climate system. Comparison of the GISP2 10Be flux with GISP2 temperature variations suggest that different mechanisms underlie Dansgaard-Oeschger events, the Younger Dryas and Termination I. A model of ice age climate variations is proposed whereby the climate alternates between two metastable states.
John,
You write: “The random walk hypothesis of Hasselmann [1976] still applies but instead of a Gaussian white noise process due to weather, terminations appear to be forced by discrete impulses which occurred about 80 or 120 kyr apart, after each of which the climate relaxed exponentially back to its prior, ice age state. ”
But we know that the 40 year cycle is the change in obliquity of the earth’s axis. When Obliquity is a maximum the arctic circle expands southwards. During summer both the northern and southern polar regions get more insolation. The 43,000 year cycle of obliquity is the only constant clock running over the last 3 million years.
Until 900,000 years ago all glaciations ran on a 41,000 year clock. Since then they have been running first on a 2 step (80,000 year) and then on a 3 step 120,000y cycle. There may be a random component as well but it is not the main driver.
You also show that Be10 coincides with D-O events implying that a change in cosmic rays coincided with these and that their origin is astronomic. But then you don’t follow that through and conclude finally that they are unexplained . Why ?
So-called Bond events also seem to be related to D-O events.
I am still looking for a causal relationship for Ice Ages.
Aloha Clive:
A causal relationship for ice ages exists. Unfortunately, the most probable cause is also the simplest, so it is too simple for academia and intellectuals. A Micronsian tree-trimmer can understand the highest probable cause of an ice age better than any ivory-tower PhDs.
If you are interested and are capable of setting aside your pre-conceptions, then I will share the cause with you – a cause that I see everyday here in the tropics, and a cause that I can and do counteract, any time I want to do so. I have seen the action needed to counteract an ice age produce notable results in as little as 8 – 10 days. Simplicity intensifies!
Hello. Another thought on your Ice age correlation.
My supposition is that for the 0-800K period, the precession’s amplitude correlates as a function of the combined effects of eccentricity and obliquity.
A(precession) = f(Obl) + f(Ecc) where A is the amplitude of the precession term
such an application could improve correlation at some of the peaks missed, such as at 620K, 440K and 40K
I made a spreadsheet and have a screenshot if you were interested.
This is basically looking at Obliquity and Eccentricity as being ‘catalysts’ of a sort for precession.
this of course begs the question, what is the mechanism then?
Take care.
JBP
Thanks for your ideas ! Any new analysis is welcome . You can post it here or email me at clive.best[at]gmail.com
It is definitely true that Obliquity and Eccentricity modulate the precession term !
regards
Clive
I note your comment on unvaccinated people. Many diseases are infectious well before symptoms appear, covid no different; so many covid sufferers are out and about spreading infection before they are aware of their status, also when symptoms do appear they can be confused with many other physical problems and are discounted by the individual for a time before going for a check up, thereby delaying further any restriction of personal movement -and, if it costs them money, check ups and voluntary restrictions are most unlikely to happen until hospitalisation. Your assumption that a human will restrict their movement voluntarily is erroneous. Perhaps you should talk to a doctor, your knowledge of the human condition seems a bit limited.
I myself caught COVID at the end of August despite being double vaccinated (Astra Zeneca). We had been on holiday in Dorset and my wife caught a “cold” first probably in a pub and tested negative. About 10 days later I got a runny nose and slight cough and tested positive on a lateral flow test and the next day positive on PCR. The vaccine didn’t stop us getting infected but probably avoided us getting very ill.
We later spent 2 weeks in quarantine in Hong Kong before seeing my son and family. There we were tested on arrival at the airport with result after 3 hours and then every 2 days in the hotel and twice more afterwards.That way Hong Kong have zero cases in the population ! Many people in Hong Kong are unvaccinated. All restaurants are open but you must wear masks outside.
Here in the U.K. COVID measures don’t work as It is based on self-isolation. Test and trace doesn’t work. Only the test bit works well. My conclusion for all this is .
Vaccination avoids getting seriously ill but doesn’t stop you catching COVID and passing it on. So transmission is unaffected by vaccination. The unvaccinated take a risk of getting seriously ill but otherwise are no more responsible than the vaccinated. They may even be less responsible for transmission because they get symptoms. The only logic to enforce vaccination would be to avoid ICR beds being overwhelmed in the NHS. Enforcing vaccine passports though is too much like persecution.