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Author Topic: Is 'Tippings' in non-linear systems aplicable to Earth?  (Read 3548 times)

Offline yor_on

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Offline yor_on

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Is 'Tippings' in non-linear systems aplicable to Earth?
« Reply #1 on: 09/01/2011 13:38:42 »
"Warm, half cold, ice cold

With completely new research results geophysicist Peter Ditlevsen, Centre for Ice and Climate at the Niels Bohr Institute, has found part of the explanation for the mystery of the sudden change of the ice ages. He has made model calculations of the climate of the past and compared it to the concrete data from seabed cores, which tell us about the climatic fluctuations of the past.

From the results he has been able to construct a diagram over the possible climatic conditions resulting from the variation in solar radiation. It appears that the ice ages and interglacial periods are not a gradual fluctuation between cold and warm climates.

What happened 1 million years ago was that the climate system went from a situation where it fluctuated between two states (cold and warm) with a 40.000 year cycle, corresponding to the dominant change in the Sun's radiation. After this period the dynamic changed so that the climate jumped between 3 states, that is to say between a warm interglacial climate like our present climate, a colder climate and a very cold ice age climate. It is still the 40.000 year variation in solar radiation which controls our current fluctuations, but it results in changing climate periods of 80.000 and 120.000 years.

Chaotic dynamic climate


The climate does not become gradually colder or warmer - it jumps from the one state to the other. That which gets the climate to jump is that when the solar radiation changes and reaches a certain threshold - a 'tipping point', the existing climate state, e.g. an ice age, is no longer viable and so the climate jumps over into another state, e.g. a warm interglacial period. In chaos dynamics this phenomenon is called a bifurcation or a 'catastrophe'.

In addition to the change in solar radiation there can be random changes in the Earth's weather variations, that contribute to triggering the bifurcation or the 'catastrophe'. Such variations are called 'noise', and a theory is, that the atmosphere's CO2 level can be an important noise-factor. This means that there is the possibility that the 'noise' is a decisive factor for very large climate changes, which can therefore be unpredictable.

There is still no explanation for the change in the climate system 1 million years ago, but one theory is that the atmosphere's CO2-level fell to the lowest level ever. If so, the manmade increase in CO2 may result in a return to 40.000 year ice age cycles.

"The new results are an important piece of the puzzle for understanding the ice ages and their climate dynamics. In the manmade climate changes, that we are possibly in the middle of now, one worries a lot about the possible so-called 'tipping points'. The bifurcations that are now identified in the natural climate fluctuations are tipping points, so this is of course an important step in our understanding of climate changes", explains Peter Ditlevsen."
« Last Edit: 09/01/2011 13:40:22 by yor_on »
 

Offline Bored chemist

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Is 'Tippings' in non-linear systems aplicable to Earth?
« Reply #2 on: 09/01/2011 16:06:44 »
You have been warned, therefore they won't arrive without warning.
 

Offline yor_on

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Is 'Tippings' in non-linear systems aplicable to Earth?
« Reply #3 on: 10/01/2011 02:11:37 »
Yeah but it seems as if the Gulf stream have started to weave a little, not that it is such a big thing, well, it is a big thing, a massive thing actually and therefore I expect it to do just fine. The Gulf stream I mean, so I'm not worried there :) We should be headed for a big sunspot maxima this year according to the common theory of sun's conveyor belt, a little like our oceans conveyor belt where the Gulf stream takes part.

And that worries me a little more, if it's going to be a whooper, especially if this is correct. We have a lot of 'noise' in this system now.
 

Offline CliffordK

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Is 'Tippings' in non-linear systems aplicable to Earth?
« Reply #4 on: 11/01/2011 05:35:33 »
We should be headed for a big sunspot maxima this year according to the common theory of sun's conveyor belt, a little like our oceans conveyor belt where the Gulf stream takes part.

And that worries me a little more, if it's going to be a whooper, especially if this is correct. We have a lot of 'noise' in this system now.
I think that has been revised.
In 2006, they were predicting a big sunspot maximum.
Since 2006, the activity actually went down to a low... (50 year low?)
I think the current prediction is for a very mild sunspot maximum either this year or next year.

If the current cycle is mild...  what will the 2020 cycle be like?

The measurement has been measured for a half a millennium.  I'm not sure if there is a bias due to new/better equipment, although I assume they've standardized reporting methods.  Activity seems to have been increasing up until recently, but has fallen off dramatically in the last decade.  There are precedents for extended periods of low solar activity in the past.

I suppose the question is...  if solar activity goes down, does that just give us a well needed, but temporary reprieve, or is it a sign of other forces at work with the global warming?

The solar cycles do seem to obfuscate warming trends...  often showing rapid shifts at the beginning of the decade due to new solar cycles beginning, then relatively little changes for the rest of the decade as the solar cycles wane.
 

Offline yor_on

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Is 'Tippings' in non-linear systems aplicable to Earth?
« Reply #5 on: 12/01/2011 01:26:43 »
Yeah, I looked at an older Nasa prediction stormwarning in where they had expected it to come 2010-11. But the latest prediction I found is Solar Cycle Prediction (Updated 2011/01/03) and there they say 2013?
 

Offline CliffordK

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Is 'Tippings' in non-linear systems aplicable to Earth?
« Reply #6 on: 05/02/2011 14:56:40 »
Yeah, I looked at an older Nasa prediction stormwarning in where they had expected it to come 2010-11. But the latest prediction I found is Solar Cycle Prediction (Updated 2011/01/03) and there they say 2013?
The sunspot (or Radio Flux) data appears to have been updated.
The "Prediction" data that NASA is distributing still says October 2010.  But, there is probably no need to update the the prediction yet.

Sunspot data and F10.7 Radio Flux data is available on a daily basis from various sources.

There seems to be a slight divergence between data types, with the Radio Flux data appearing somewhat flatter than the Sun Spot data.

Anyway, the indications are that the current solar cycle will be at least as low as the solar cycle in the late 60's and early 70's that caused significant global weather perturbations, perhaps significantly lower, and possibly influencing weather for the next 2 decades or so.
 

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Is 'Tippings' in non-linear systems aplicable to Earth?
« Reply #6 on: 05/02/2011 14:56:40 »

 

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