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Climatic Equilibrium


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Posted
  • Location: South Woodham Ferrers, height 15 metres
  • Location: South Woodham Ferrers, height 15 metres

Like "coloured" presupposes the existence of "plain", a notion of Climate Change cannot be held without the existence of a Climatic equilibrium.

What is Climatic equilibrium, in which period of Earth's history has this occurred, and so what does that make "Climate Change"?

Let's start with a few graphs:

Was this period an equilibrium?

climate-history-ipcc.gif

Was this equilibrium?

HoloceneOptimumTemperature.jpg

Was this equilibrium?

petit150.jpg

How about this - was this equilibrium?

Climate.jpg

This?

Five_Myr_Climate_Change.png

As you might have noticed as you viewed the five graphs in the order presented, as one's perspective on Earth's history broadens, from thousands, tens of thousands, hundreds of thousands to millions of years, one's notion of climatic equilibrium scales up. The terms encompass greater and greater amounts of climate change, until both concepts become useless.

Within the "Climate Change" discussion there is a commonly made observation that any change to the Earth's climate today will be relatively minuscule compared to those changes that have occurred throughout history. Therefore, there is no climate change.

But, of course, human civilisation has only been around for thousands of years, and is unlikely to be on the planet for the length of time to experience hundreds of thousands - if not millions - of years of climate change.

The long-term variability of the Earth's climate means if there is such a thing as climate change or climatic equilibrium we first define at what scale we consider climate change to occur where the equilibrium is to be, and that must be at a scale relevant to human living.

I suggest then that Climatic equilibrium must be related to a very small portion of historical time: the last 12'000 years since the last ice age. The "climatic equilibrium" that "climate change" is purportedly changing the climate away from is the interglacial period. This therefore means Climate chang reflects either a dramatic cooling or dramatic warming away from or towards ice age conditions.

Any change that is not of that magnitude is within our current Climatic equilibrium - the interglacial period - and therefore is not climate change.

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Posted
  • Location: Dorset
  • Location: Dorset

You were doing so well upto the end.

"Any change that is not of that magnitude is within our current Climatic equilibrium - the interglacial period - and therefore is not climate change"

Climate is change that can be measured over 30 years, climate is judged over 30 years. Look at any definition of climate you want.

Also the civilisation we have on our planet now is very very different to the civilisation even 100 years ago with billions more people, hence what you say doesn't make sense from that POV either.

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Posted
  • Location: South Woodham Ferrers, height 15 metres
  • Location: South Woodham Ferrers, height 15 metres

Surely they don't believe it has tipped already?

Not even Al Gore says that, though he did say there will be no Arctic Ice in a couple of years.

As I understand it, even the most ardent global warming supporters are working of projections and computer models. Right or wrong, these formed the basis of the IPCC reports.

Nobody has yet officially claimed we are "beyond the tipping point" though many have claimed we are on it. Right?

"Any change that is not of that magnitude is within our current Climatic equilibrium - the interglacial period - and therefore is not climate change"

Climate is change that can be measured over 30 years, climate is judged over 30 years. Look at any definition of climate you want.

Do you have a definition of Climatic equilibrium - that's my discussion topic. I'd be interested to know what yours is.

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Posted
  • Location: Beccles, Suffolk.
  • Weather Preferences: Thunder, snow, heat, sunshine...
  • Location: Beccles, Suffolk.

Well, I guess the most obvious thing is that climatic equilibrium is dynamic as opposed to static. But, in itself, that says nothing about whether-or-not any tipping-point has been reached.

For the record, I doubt it has.

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Posted
  • Location: A small planet somewhere in the vicinity of Guildford, Surrey
  • Location: A small planet somewhere in the vicinity of Guildford, Surrey
You were doing so well upto the end.

"Any change that is not of that magnitude is within our current Climatic equilibrium - the interglacial period - and therefore is not climate change"

Climate is change that can be measured over 30 years, climate is judged over 30 years. Look at any definition of climate you want.

Also the civilisation we have on our planet now is very very different to the civilisation even 100 years ago with billions more people, hence what you say doesn't make sense from that POV either.

I don't think the argument is one of definition but one of scale.

We all know that the modern definition of climate is "weather averaged over 30 years", but what scale of climate change can be regarded as beyond the oscillation you would expect of a dynamic equilibrium?

CB

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Posted
  • Location: Dorset
  • Location: Dorset

There is no such as climate equilibrium in real life, there is an upper and lower point at which climate fluctuates i.e over the last 100 years, there is a base level which is determined by natural factors such as the earth position to the sun and the position of the continents etc. This is what I believe your graph is showing. But this has nothing to do with your final sentence about climate change.

"but what scale of climate change can be regarded as beyond the oscillation you would expect of a dynamic equilibrium?"

I really don't understand the question, I could give a glib answer of 10C either way, but that's not the point, over what time scale is the dynamic equilabrium ?. 100 years, 1000 years, 10000 years.

Finally this statement is gibberish.

"This therefore means Climate chang reflects either a dramatic cooling or dramatic warming away from or towards ice age conditions"

No it doesn't, no climate scientist has ever said this that I am aware of.

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Posted
  • Location: A small planet somewhere in the vicinity of Guildford, Surrey
  • Location: A small planet somewhere in the vicinity of Guildford, Surrey
There is no such as climate equilibrium in real life, there is an upper and lower point at which climate fluctuates i.e over the last 100 years, there is a base level which is determined by natural factors such as the earth position to the sun and the position of the continents etc. This is what I believe your graph is showing. But this has nothing to do with your final sentence about climate change.

The highlighted part above is the very definition of a dynamic equilibrium!

"but what scale of climate change can be regarded as beyond the oscillation you would expect of a dynamic equilibrium?"

I really don't understand the question, I could give a glib answer of 10C either way, but that's not the point, over what time scale is the dynamic equilabrium ?. 100 years, 1000 years, 10000 years.

AFT suggested a time scale of 12,000 years, which does not seem unreasonable to me. But, to be entirely honest, it was kind of a rhetorical question. What scale of climate change (or temperature change, if you like) can be regarded as extreme or unusual? Does anyone have a definitive answer to this question? We are told that the current temperature is unusual or extreme (or heading that way) on the basis of a very limited set of data, but how unusual is it actually?

Finally this statement is gibberish.

"This therefore means Climate chang reflects either a dramatic cooling or dramatic warming away from or towards ice age conditions"

No it doesn't, no climate scientist has ever said this that I am aware of.

The above statement seems to be unsubstantiated (not actually gibberish) when you take it out of context like that, but given AFT's preceding statements "I suggest then that Climatic equilibrium must be related to a very small portion of historical time: the last 12'000 years since the last ice age. The "climatic equilibrium" that "climate change" is purportedly changing the climate away from is the interglacial period" it makes far more sense.

I assume that AFT's intention - given that he started a new thread for his post - was to provoke discussion. The statement you declare "gibberish" is based upon the assumptions made in the preceding statements.

CB

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Posted
  • Location: Huddersfield, 145m ASL
  • Weather Preferences: Lots of snow, lots of hot sun
  • Location: Huddersfield, 145m ASL

Wood for trees ???? So many threads, so many interminable 'discussions', so many circular arguments.

I feel that the central issue is being lost in all this 'robust discussion'. Surely the issue here is not whether man is making the climate warmer/colder/whatever. The main question as far as I can see is, is man having a detrimental effect on the global climate, specifically from a human perspective i.e. are our activities, (and as far as I'm concerned this doesn't just include C02 generation, but also deforestation, desertification, intensive agriculture, livestock numbers and so on, which can all affect local climates), having a negative impact on the local climate specifically froma human existence perspective. And that is where I think all the effort should be concentrated - are mans activities contributing to more severe droughts, more severe storms, quicker warming of colder climes etc etc.

I don't see the point of discussions about whether we're changing 100,000 year climate cycles or not, unless these changes are linked to a potential deterioration of local weather in terms of it's effects on daily life. Would there be any point in these discussions if climate change, (AGW or not), was true, but it had no noticeable effect on our lives at all, either today or in 100 years time ?

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Posted
  • Location: Dorset
  • Location: Dorset

Maybe this will help, various reconstructions over the last 12K.

Anything between 1.5 to -3C seems to possibly have occured in the last 12K. Add on to this a contingency that the max and min might not have been reached and you might end up with 3C to -6 which unworkably large.

However if you take it back to 10K it's much more stable and you can argue that we've never been this high before.

This is why taking a timeframe at random is rather meaningless.

post-6326-1246538991_thumb.png

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Posted
  • Location: A small planet somewhere in the vicinity of Guildford, Surrey
  • Location: A small planet somewhere in the vicinity of Guildford, Surrey
Wood for trees ???? So many threads, so many interminable 'discussions', so many circular arguments.

I feel that the central issue is being lost in all this 'robust discussion'. Surely the issue here is not whether man is making the climate warmer/colder/whatever. The main question as far as I can see is, is man having a detrimental effect on the global climate, specifically from a human perspective i.e. are our activities, (and as far as I'm concerned this doesn't just include C02 generation, but also deforestation, desertification, intensive agriculture, livestock numbers and so on, which can all affect local climates), having a negative impact on the local climate specifically froma human existence perspective. And that is where I think all the effort should be concentrated - are mans activities contributing to more severe droughts, more severe storms, quicker warming of colder climes etc etc.

I don't see the point of discussions about whether we're changing 100,000 year climate cycles or not, unless these changes are linked to a potential deterioration of local weather in terms of it's effects on daily life. Would there be any point in these discussions if climate change, (AGW or not), was true, but it had no noticeable effect on our lives at all, either today or in 100 years time ?

Hi,

this is an issue that keeps being brought up. I have responded before, but since it's been a while since I last laid my cards out then I shall do it again. :(

I believe that man is having a local impact. This is plain to see on a really local scale every time a copse of trees is uprooted for the sake of yet another 47-storey apartment complex.

I believe that we should limit our damage to the environment - we don't drop chewing gum on our living room carpet, so why do some find it acceptable to drop it on the pavement, or stick it to a tree?

I believe that a lot of people need to learn about social responsibility (and about personal responsibility) and how helping other people helps you yourself out in the end.

I believe we should recycle.

I believe we should find alternative energy sources, not least because of the sustainability issue.

I believe we should save the whale.

But I don't believe in AGW.

Does my non-acceptance of AGW mean that I don't recycle? Does it mean that I think we should damage the environment? Does it mean that I deny my social responsibility?

Absolutely not.

Why do I come on these boards and debate the intricacies of AGW if I accept a lot of the "We Should Clean Up Our Act" stuff? Because I love science, I like talking about science, and I love discussing science.

None of the discussions on these boards make any difference to our individual actions. If a "Pro-AGW" person was convinced by a skeptic that man was having no impact on global climate, would that "Pro" then start sullying the streets and stop recycling? I doubt it, somehow.

If a skeptic was convinced by a Pro that man was having an effect on the environment then would the skeptic have to change his or her ways? I think that the skeptics who care enough to read and write about AGW on these boards are already happy recycling and using as little electricity as possible, for reasons entirely separate from AGW.

I genuinely believe that the AGW hypothesis is deeply flawed, overly politicised and not analysed as strictly as is warranted for such a profound scientific study. I will argue against it until I am either convinced that it is broadly accurate or until I am blue in the face (whichever comes first), but I will continue the discussion for the same reason that I engage in discussions about politics, religion and the daily news:

because I enjoy it.

:o

CB

Maybe this will help, various reconstructions over the last 12K.

Anything between 1.5 to -3C seems to possibly have occured in the last 12K. Add on to this a contingency that the max and min might not have been reached and you might end up with 3C to -6 which unworkably large.

However if you take it back to 10K it's much more stable and you can argue that we've never been this high before.

This is why taking a timeframe at random is rather meaningless.

Is not 30 years just another random timeframe though?

:(

CB

PS - I shan't talk about the graph itself for now, but I can if you want me to...!

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Posted
  • Location: Blackburn, Lancs
  • Location: Blackburn, Lancs

That's the point I was trying to make CB, regarding this 30 year timescale. This is what I can't understand, why 30 years? With that logic, you can choose any given timescale to prove your own point. I keep saying it, but climate science is in it's infancy, and yet we have people on here who seem to know without any doubt, that what the climate models are telling them is gospel.

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Posted
  • Location: Huddersfield, 145m ASL
  • Weather Preferences: Lots of snow, lots of hot sun
  • Location: Huddersfield, 145m ASL
Why do I come on these boards and debate the intricacies of AGW if I accept a lot of the "We Should Clean Up Our Act" stuff? Because I love science, I like talking about science, and I love discussing science.

I genuinely believe that the AGW hypothesis is deeply flawed, overly politicised and not analysed as strictly as is warranted for such a profound scientific study. I will argue against it until I am either convinced that it is broadly accurate or until I am blue in the face (whichever comes first), but I will continue the discussion for the same reason that I engage in discussions about politics, religion and the daily news:

because I enjoy it.

I wouldn't argue with that really, except that this particular argument (AGW or not ?) is definitely not going to be resolved until long long after we've gone. I can appreciate scientific research, I can appreciate the occasional posts that pop on the climate change threads which contain links to genuine research results in this field, but what I think is pointless is the 99% or so posts which are one side or the other trying to present compelling proof to back up their argument. That simply does not exist, and because no proof exists, how can any meaningful discussion ever be concluded ? Most of these threads could be summed up by long streams of three word posts - 'Yes it does' 'No it doesn't' - without any prospect of resolution, or even much in the way of progression, because the 'clinchers' which might move the discussion on one way or the other are not anywhere near being available, so all we get is lots of groundless conjecture and, when that runs out, sniping.

Unless we are actually indulging in a philosophical discussion of course, where the rigour is not in searching for a definitive answer, but in the crafting of the argument itself ?

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Posted
  • Location: A small planet somewhere in the vicinity of Guildford, Surrey
  • Location: A small planet somewhere in the vicinity of Guildford, Surrey

While I think it would be wonderful to be able to reach a definitive conclusion, I have to say that I enjoy the discussion for the sake of the discussion. I would say that this is a philosophical discussion - engaging people in the debate, even if the debate can never be resolved, gets them thinking and I believe there are far too many people in this world who don't exercise their brains enough!

I would also add that, while some people rail against the idea of "point-scoring", half the fun of the debate is to out-think your opposite number and, yes, even score metaphorical points. I would heartily encourage people to present logically thought out arguments and counter-arguments; the more logically rigorous argument would, by that token, be the winner of the point...at least until a better counter-argument is presented.

Come, people - craft your arguments!

:D

CB

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Posted
  • Location: Dorset
  • Location: Dorset
That's the point I was trying to make CB, regarding this 30 year timescale. This is what I can't understand, why 30 years? With that logic, you can choose any given timescale to prove your own point. I keep saying it, but climate science is in it's infancy, and yet we have people on here who seem to know without any doubt, that what the climate models are telling them is gospel.

It's 30 years because it is...That's the timescale that we notice has an effect on the the climate that a certain area contains. It also by and large discounts short term changes. It's a bit like saying why does tennis have the scoring system it does and not 1,2,3,4 etc. Basically it wouldn't be tennis anymore, just like if we use a different timeframe for climate, it wouldn't be climate anymore.

I would urge you to read a good book on ecology and climate if you really don't understand the 30 year bit. (and I mean that nicely).

As to climate models and gospel, nowhere, never has this been said.

The graph's accuracy isn't really the point though CB, the point is that comparing todays temperature with variation 5K,10K,12L or 50K ago and talking about equilbriums just doesn't make sense, the world was still coming out of an iceage 12K years ago, so the temperatures achieved then have no bearing on what ca nbe achieved today.

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Posted
  • Location: A small planet somewhere in the vicinity of Guildford, Surrey
  • Location: A small planet somewhere in the vicinity of Guildford, Surrey
The graph's accuracy isn't really the point though CB, the point is that comparing todays temperature with variation 5K,10K,12L or 50K ago and talking about equilbriums just doesn't make sense, the world was still coming out of an iceage 12K years ago, so the temperatures achieved then have no bearing on what ca nbe achieved today.

When did I say anything about the graph's accuracy? All I said was that I could comment on the graph if you wanted me to.

You seem to have misunderstood what I'm talking about with regards to a dynamic equilibrium. Clearly it is unfair to compare modern temperatures with temperatures 12,000 years ago. What we're talking about is not "temperatures 12,000 years ago", it is the range of temperatures over the 12,000 year period from the end of the last ice age to the present.

And since we're currently in an interglacial, can it not be argued that we are still, even now, coming out of an ice age?

CB

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Posted
  • Location: Blackburn, Lancs
  • Location: Blackburn, Lancs
It's 30 years because it is...That's the timescale that we notice has an effect on the the climate that a certain area contains. It also by and large discounts short term changes. It's a bit like saying why does tennis have the scoring system it does and not 1,2,3,4 etc. Basically it wouldn't be tennis anymore, just like if we use a different timeframe for climate, it wouldn't be climate anymore.

I would urge you to read a good book on ecology and climate if you really don't understand the 30 year bit. (and I mean that nicely).

As to climate models and gospel, nowhere, never has this been said.

The graph's accuracy isn't really the point though CB, the point is that comparing todays temperature with variation 5K,10K,12L or 50K ago and talking about equilbriums just doesn't make sense, the world was still coming out of an iceage 12K years ago, so the temperatures achieved then have no bearing on what ca nbe achieved today.

Thanks for the offer, but I don't need bringing up to speed thank you. Maybe we should start a graph showing 11 years of no warming hey! 30 years is still far too short a time, for anything else other than a trend! And that's all we have Iceberg a trend. Let's see were we are in another 3-5 years, and if we continue to see no warming, what then?

When did I say anything about the graph's accuracy? All I said was that I could comment on the graph if you wanted me to.

You seem to have misunderstood what I'm talking about with regards to a dynamic equilibrium. Clearly it is unfair to compare modern temperatures with temperatures 12,000 years ago. What we're talking about is not "temperatures 12,000 years ago", it is the range of temperatures over the 12,000 year period from the end of the last ice age to the present.

And since we're currently in an interglacial, can it not be argued that we are still, even now, coming out of an ice age?

CB

Exactly CB, we are still coming out of an ice age. Too many base all their assumptions on evidence that's far from concrete!!

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Posted
  • Location: Beccles, Suffolk.
  • Weather Preferences: Thunder, snow, heat, sunshine...
  • Location: Beccles, Suffolk.
Exactly CB, we are still coming out of an ice age. Too many base all their assumptions on evidence that's far from concrete!!

We may well be coming out of an ice age, SC; though we may equally well be entering one. Who knows?

You're right enough though: too many do indeed base their hypotheses on baseless assumptions.

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Posted
  • Location: Blackburn, Lancs
  • Location: Blackburn, Lancs
We may well be coming out of an ice age, SC; though we may equally well be entering one. Who knows?

You're right enough though: too many do indeed base their hypotheses on baseless assumptions.

Oh if I didn't know you better, I would have thought that was a dig at me! :doh:

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Posted
  • Location: South Woodham Ferrers, height 15 metres
  • Location: South Woodham Ferrers, height 15 metres
There is no such as climate equilibrium in real life, there is an upper and lower point at which climate fluctuates i.e over the last 100 years, there is a base level which is determined by natural factors such as the earth position to the sun and the position of the continents etc. This is what I believe your graph is showing. But this has nothing to do with your final sentence about climate change.

I did not mean to suggest there was a literal equilibrium of stable temperature.

What I mean is, if over the last 12k yr - the interglacial - the temperature has not gone above or below 1 degree Celsius that's as good as Climatic equilibrium we're going to get that is relevant to human kind.

If suddenly the temperature change significantly exceeded 1 degree Celsius in either direction then that would break the Climatic equilibrium we have and be Climate Change.

Right or wrong, most of the IPCC models suggest the 1 degree Celsius ceiling will be broken, so I would say these models predict Climate Change.

"but what scale of climate change can be regarded as beyond the oscillation you would expect of a dynamic equilibrium?"

I really don't understand the question, I could give a glib answer of 10C either way, but that's not the point, over what time scale is the dynamic equilabrium ?. 100 years, 1000 years, 10000 years.

I know you weren't replying to me here but that's actually the point I made with the multiple graphs. What is the scale you work with? I've suggested 12k years - the interglacial.

Finally this statement is gibberish.

"This therefore means Climate change reflects either a dramatic cooling or dramatic warming away from or towards ice age conditions"

No it doesn't, no climate scientist has ever said this that I am aware of.

I'm sure it's been said before the the only point I'm making is: I'm saying it. I'm proposing, by way of discussion, that the most appropriate scale for Climatic equilibrium is the last 12k years, which saw the end of the last ice age.

We know from previous ice ages and interglacials that our interglacial is normal and possibly cyclical. Therefore at this scale Climate Change would be a move back toward ice age or away from Ice Age (i.e. the cycle of ice ages and interglacials gets broken).

Of course, there are climate changes at other scales. But I've proposed that the most relevant scale is the last 12k years.

But, perhaps I'm wrong? Perhaps even 12,000 years, and a + or - of 1 degree Celsius encompasses far too much variation for humankind?

Why would this be?

Perhaps because human development and agriculture is today at a global scale we want to make the climate more predictable, manage the global climate like it was a single, giant air-conditioning system.

In which case Climate Changes of + or - 1 degree Celsius, little ice ages and warm periods, may be too dramatic and thus invalidate this 12k yr period as a Climatic equilibrium.

In which case Climate Changes over one year, or even a decade might be thought of as troublesome and to be avoided.

(However, in my view I think I would stick to 12k yr as I'm generally skeptical of humankind's ability to micro-manage anything, let alone micro-manage the global climate system).

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Posted
  • Location: Dorset
  • Location: Dorset
Thanks for the offer, but I don't need bringing up to speed thank you. Maybe we should start a graph showing 11 years of no warming hey! 30 years is still far too short a time, for anything else other than a trend! And that's all we have Iceberg a trend. Let's see were we are in another 3-5 years, and if we continue to see no warming, what then?

Exactly CB, we are still coming out of an ice age. Too many base all their assumptions on evidence that's far from concrete!!

SC, please don't take offence when none was given. If you don't understand why 30 years is the given timeframe to study climate then you need to understand why the 30 years was choosen.

I honestly think that people in general would benefit from understand climate what is it and what climate science is (particularly before starting to slag off climate scientists).

Right I've got a few mins so as a very basic overview.

wladimir Koppen started climate classification around 100 years ago. see wiki (as it's easy for me to find! )

http://en.wikipedia.org/wiki/Wladimir_K%C3%B6ppen

Once areas of the globe have been classified into climatic groups we need to distinguish the charecterisitics that lead to each group which in the short time frame is weather. Now I know everybody knows that climate is basically the average of weather for an area such that you can predict the average of that weather that needs to exist to sustain the climate.

The WMO came up (way before AGW and climate change as a seperate science) with an average of 30 years. Using this average and assuming that this average was hit the climate would be sustained in it's current form.

For example if over a 30 year period the precip for an area was only say 80% of the previous 30 years there would be a good chance that the underlying climate classification would change.

This can be taken to a micro level with indervidual classification (maybe 80 or so for the UK as per Rodwell, if my memory serves me).

http://www.ucar.edu/learn/1_2_2_9t.htm This is quite an easy to understand overview of climate and climate change.

So essentially 30 years is choosen for

a) this is the length of time it takes generally for a sustained change in weather to lead to a sustained change in the underlying climate classification.

:lol: It provides a useful average needed sustain a climate in it's current state.

c) deviations from the 30 years tend to be more useful and significant.

20 years isn't long enough. 40 years is too far.

30 years isn't for trends it's for the sustainability of the underlying climate classification as an average.

AFT did you see my post re 12K being used and the temp variation that would enduce ?.

The problem is that 12K years ago the world was a different place with ice in places that are now open grass lands, seas that were shallower, albedo's that were different.

I think I understand why your trying to get at but as I've shown above climate change is not a measureable equilbrium over a time frame it's a set of charecteristics that determine the climate classification of a piece of the earth.

Somewhere like south Greenland has probably changed climate classification several times in the last 12K, so have areas of Africa and North America.

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Posted
  • Location: South Woodham Ferrers, height 15 metres
  • Location: South Woodham Ferrers, height 15 metres
So essentially 30 years is choosen for

a) this is the length of time it takes generally for a sustained change in weather to lead to a sustained change in the underlying climate classification.

:) It provides a useful average needed sustain a climate in it's current state.

c) deviations from the 30 years tend to be more useful and significant.

20 years isn't long enough. 40 years is too far.

30 years isn't for trends it's for the sustainability of the underlying climate classification as an average.

Are you posting this because you agree with it or because you are just passing along information?

If you do agree with it, can I ask you which 30 year period this Climatic equilibrium is.

Is it the max -/+ variation in temperature between 1970 - 2000? 1960 - 1990?

Why did you choose this period of thirty years?

AFT did you see my post re 12K being used and the temp variation that would enduce ?.

The problem is that 12K years ago the world was a different place with ice in places that are now open grass lands, seas that were shallower, albedo's that were different.

I think I understand why your trying to get at but as I've shown above climate change is not a measureable equilbrium over a time frame it's a set of charecteristics that determine the climate classification of a piece of the earth.

Somewhere like south Greenland has probably changed climate classification several times in the last 12K, so have areas of Africa and North America.

This is an interesting point, and adds to the discussion, but I disagree that this must change my view, because I think environmental change is also subject to scale.

This interglacial, with its -/+ 1 degrees Celsius coolings and warmings has had certainly seen great environmental changes and that this is significant to how humanity has lived.

Indeed, temperature induced changes in rainfall patterns may have caused the downfall of a number of civilisations over the last 12k years.

However, my proposal is that a -/+ 3 degree Celsius cooling or warming would have an even greater environmental Climate Change - alarmists say that sort of change could wipe out humanity - than a -/+ 1 degree Celsius cooling or warming.

So, I repeat: it's a question of scale. I choose -/+ 1 degree Celsius (or, the last 12k yrs, which is saying the same thing). This means I have to accept within my Climatic equilibrium it is possible for significant environmental change that could severely impact humanity. However, it also means I reject that this Climatic equilibrium, if it remains an equilibrium, could threaten to wipe out humanity. For that would require Climate Change: -/+ 3 degrees temperature change.

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Posted
  • Location: Dorset
  • Location: Dorset

Are you posting this because you agree with it or because you are just passing along information?

Both

If you do agree with it, can I ask you which 30 year period this Climatic equilibrium is.

Is it the max -/+ variation in temperature between 1970 - 2000? 1960 - 1990?

Why did you choose this period of thirty years?

ATM this is choosen by the WMO and is 60-90, its not something that has been choosen by any AGW person, I've heard rumours that it will change to 70-00 next year. Climate is temperature/precip/humidity, windspeed etc all put together not just temperature. Climate is not just about the globe as a whole but also how varying parts of it intereact.Significant deviations away from the 30 year mean can lead to climate change. I don't think you can say there is a max min for it to occur as it will depend upon the fragility of the climate type in question.

This is an interesting point, and adds to the discussion, but I disagree that this must change my view, because I think environmental change is also subject to scale.

This interglacial, with its -/+ 1 degrees Celsius coolings and warmings has had certainly seen great environmental changes and that this is significant to how humanity has lived.

agree

Indeed, temperature induced changes in rainfall patterns may have caused the downfall of a number of civilisations over the last 12k years.

almost certainly.

However, my proposal is that a -/+ 3 degree Celsius cooling or warming would have an even greater environmental Climate Change - alarmists say that sort of change could wipe out humanity - than a -/+ 1 degree Celsius cooling or warming.

So, I repeat: it's a question of scale. I choose -/+ 1 degree Celsius (or, the last 12k yrs, which is saying the same thing). This means I have to accept within my Climatic equilibrium it is possible for significant environmental change that could severely impact humanity. However, it also means I reject that this Climatic equilibrium, if it remains an equilibrium, could threaten to wipe out humanity. For that would require Climate Change: -/+ 3 degrees temperature change.

I don't think it will wipe out humanity even at 3 or 4C.

I think my main issue is with the term equilibrium as this isn't it see def below.

"Equilibrium is the condition of a system in which competing influences are balanced,The stationary point of a dynamical system is often called an equilibrium"

Your talking about significant deviations from current climate to be measured over 12K years instead of 30 years, what your talking about is almost a geological concept of climate change which can be use to measure over larger timeframes, interstadials, interglacials etc which might well make sense, but IMO it doesn't make sense to use this geological concept to describe climate change over a 5,10 or even 100 year period.

If your talking about a what period can severely impact humanity again IMO anything beyond the 100 year average I think would have a big impact.

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  • Location: South Woodham Ferrers, height 15 metres
  • Location: South Woodham Ferrers, height 15 metres
ATM this is choosen by the WMO and is 60-90, its not something that has been choosen by any AGW person, I've heard rumours that it will change to 70-00 next year. Climate is temperature/precip/humidity, windspeed etc all put together not just temperature. Climate is not just about the globe as a whole but also how varying parts of it intereact.Significant deviations away from the 30 year mean can lead to climate change. I don't think you can say there is a max min for it to occur as it will depend upon the fragility of the climate type in question.

So if I'm right, you believe 1960-1990 represents Climatic equilibrium, and you don't want the Climate to get warmer or cooler than the maximum warming and cooling that occurred during this period?

That places your Climatic equilibrium at +/- 0.3 degrees Celsius. You want the Earth to stay within that temperature deviation from the average.

I don't think it will wipe out humanity even at 3 or 4C.

I think my main issue is with the term equilibrium as this isn't it see def below.

"Equilibrium is the condition of a system in which competing influences are balanced,The stationary point of a dynamical system is often called an equilibrium"

The term "Climate Change" presupposes a Climatic equilibrium to change away from and often this is made explicit. Have you not heard or yourself used the phrase "to tip the Earth's balance"?

Because the Earth's climate is in constant flux, in order for the term "Climate Change" to have any practical meaning to us as humans there must be a Climatic equilibrium that is to be changed away from.

Your talking about significant deviations from current climate to be measured over 12K years instead of 30 years, what your talking about is almost a geological concept of climate change which can be use to measure over larger timeframes, interstadials, interglacials etc which might well make sense, but IMO it doesn't make sense to use this geological concept to describe climate change over a 5,10 or even 100 year period.

You've not quite got what I said. Forget about the 12'000 years bit! The number of years is irrelevant! The bit that matters is the +/- 1 degree Celsius temperature range.

Paleoclimatological records appear to show the temperature of the interglacial remaining within a 2 degree Celsius corridor of equilibrium. I'm suggesting if the temperature goes outside that corridor, that would be Climate Change.

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  • Location: Blackburn, Lancs
  • Location: Blackburn, Lancs
SC, please don't take offence when none was given. If you don't understand why 30 years is the given timeframe to study climate then you need to understand why the 30 years was choosen.

I honestly think that people in general would benefit from understand climate what is it and what climate science is (particularly before starting to slag off climate scientists).

Right I've got a few mins so as a very basic overview.

wladimir Koppen started climate classification around 100 years ago. see wiki (as it's easy for me to find! )

http://en.wikipedia.org/wiki/Wladimir_K%C3%B6ppen

Once areas of the globe have been classified into climatic groups we need to distinguish the charecterisitics that lead to each group which in the short time frame is weather. Now I know everybody knows that climate is basically the average of weather for an area such that you can predict the average of that weather that needs to exist to sustain the climate.

The WMO came up (way before AGW and climate change as a seperate science) with an average of 30 years. Using this average and assuming that this average was hit the climate would be sustained in it's current form.

For example if over a 30 year period the precip for an area was only say 80% of the previous 30 years there would be a good chance that the underlying climate classification would change.

This can be taken to a micro level with indervidual classification (maybe 80 or so for the UK as per Rodwell, if my memory serves me).

http://www.ucar.edu/learn/1_2_2_9t.htm This is quite an easy to understand overview of climate and climate change.

So essentially 30 years is choosen for

a) this is the length of time it takes generally for a sustained change in weather to lead to a sustained change in the underlying climate classification.

B) It provides a useful average needed sustain a climate in it's current state.

c) deviations from the 30 years tend to be more useful and significant.

20 years isn't long enough. 40 years is too far.

30 years isn't for trends it's for the sustainability of the underlying climate classification as an average.

AFT did you see my post re 12K being used and the temp variation that would enduce ?.

The problem is that 12K years ago the world was a different place with ice in places that are now open grass lands, seas that were shallower, albedo's that were different.

I think I understand why your trying to get at but as I've shown above climate change is not a measureable equilbrium over a time frame it's a set of charecteristics that determine the climate classification of a piece of the earth.

Somewhere like south Greenland has probably changed climate classification several times in the last 12K, so have areas of Africa and North America.

Iceberg I know all about Wladimir Koppen, my point is that 30 years still only shows a trend, nothing more, nothing less! 11 years have now passed with temps remaining static, this is also just a trend. It's what happens from here on, that we can only speculate about. But it seems too many people have a Tardis, and already know the outcome.
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