Does a 'Global' Temperature exist?

[Dorts]

An interesting new paper attempts to answer this question.

http://www.uoguelph.ca/~rmckitri/res...bTemp.JNET.pdf

Here's the 'Abstract' from the paper:

"Physical, mathematical and observational grounds are employed to show that there is no physically meaningful global temperature for the Earth in the context of the issue of global warming.

While it is always possible to construct statistics for any given set of local temperature data, an infinite range of such statistics is mathematically permissible if physical principles provide no explicit basis for choosing among them. Distinct and equally valid statistical rules can and do show opposite trends when applied to the results of computations from physical models and real data in the atmosphere.

A given temperature field can be interpreted as both “warming” and “cooling” simultaneously, making the concept of warming in the context of the issue of global warming physically ill-posed."


Dorts.

[King Edward]

This is hardly a new paper - it was published back in 2007. See here for a response from a climatology perspective.

[STYRBJORN]

So the Earth is just as warm during a major glaciation as during an Interglacial?

The warming sceptics do seem very good at reaching their conclusions first then looking for evidence in support. "Don't bother me with facts, I've made up my mind without any."

[wanlock dod]

Whilst I wouldn't disagree that a truly representative "global avearge temperature" is extremely tricky to define in terms of the actual temperature of the earth at any given moment, there is still a need to express an "average global temperature". The need for such a value allows different different models and projections of climate to be compared in terms of their "average temperatures".

A "global average temperature" could be expressed as the mean of the average daily temperatures in London, Sydney, New York, and Hong Kong. It might not mean much in terms of how warm, or otherwise, the earth actually is, but if different competing global models all use this same value for making comparisons it has a valid and useful purpose.

To suggest that anthropogenically caused global warming cannot be occuring simply because it is difficult to define (or perhaps agree upon?) an "average global temperature" strikes me as extremely naieve.

I can't help feeling that Styrborn might have hit upon the real issue.

[Klaas Reißmann]

Hi,

I think the word "global temperature" or "global average temperature" is a question how one defines it. I can take global warming by the meaning of the words. Than I need the temperature of any squarefoot in the world during the last x years. I can calculate on this numbers and maybe find out if it is getting warmer or not. Or I can take the meaning by saying there is a change, that let us know that this change is not "normal" by comparing to the temperatures of the last 150 years (since around 150 years meteorologists keep tabbels of the change in temperatures and weather).

But to say the truth: 150 years in the lifetime of earth is like a small part of a blink of an eye and like we try to find out by the way the patient is blinking what desease he's got.

There is no need of discussing if we have a warm phase and if it is warming up or not. It is getting warmer. I just need to have a look at all those invertebrates moving from south more and more northwards. The warmth loving species get more in Germany, the coldness loving ones get more and more rare and avoid more and more to the north.

The question is, is it really men who causes the warmth or is it just naturally and men is giving a little on top. My feeling is that no one really knows what factors are responsible for warming and do we know really all of them? We had warmth in former times as well as coldness. In the 70th and the beginning 80th in the last century I got tought on school that we are in an Interglacial and that the next ice age is not far away. But what does "far away" mean? In the life of earth it can be one year or one thousand years.

Today they teach that there is no ice age comming, but we're having a warmth. And it is getting more and more warm. We need to stop producing CO2 and therefor we need higher taxes on oil and everything we burn and produce CO2 with. I have the feeling, that this is just political wanted to raise taxes and the truth is somewhere between all politicians and scientists of the different camps say.

At least in my mind it is an illusion to think we can stop this, even if it is because of the CO2 we produce, because the quantities of CO2 is not getting less, but more and more and more.

Regards
Klaas

[bigdave60dog]

Oh! so why are all of our sandeels moving north and our seabird colonies dying out ?
Why is our sea level increasing? (I watch this first two happening from my house all of the time)
Why is our weather changing?
Why are deserts growing every year?
I could go on but I am sure that you get my point.
Dave

[Crumble]

I think the point is that there's no disputing the warming of the earth. Through studies of ice cores, etc, the scientists (not politicians) have deduced an expected warming effect due to natural cycles. There is a large degree of uncertainty in this but they have minimums and maximums. The rate of warming we have seen in the last one or two hundred years has exceeded this expected rate and coincidentally, it has happened soon after the industrial revolution in the West and accelerated during the past 50 years or so. In line with man made greenhouse gas emissions.
I think the scientists would agree that they cannot prove anything one way or the other (other than the warming is happening and accelerating) but they can look at the evidence and make educated deductions.
The reductions in carbon emissions is part of the precautionary principle. If we do nothing and it's man made, then by the time we can really prove it, it's too late to do anything about it and much of the earth's ecosystems will struggle to continue as they are. They will adapt but may not be conducive to supporting the human population.
If we take action and reduce greenhouse gas emissions, and it turns out to be a natural cycle, then at least we're all living a bit more efficiently and less reliant on polluting fuels, etc.
The sea level rise observed, particularly in the south and east, is partly due to the post glacial rebound which is causing the island to level itself after the frozen north sank slightly from extra weight of ice during the last ice age.
So there's a double whammy from the rebound and the rising sea level, which again can't be denied.
I hope I'm not retreading too much old ground but I thought I could maybe clarify a few points.

Rob

[Klaas Reißmann]

Hi Dave,

there is no need to get your point. There seems to be more need for you to read my statement again. But before surching for it and loosing a lot of time, I'm willing to cite or to quote myself:

There is no need of discussing if we have a warm phase and if it is warming up or not. It is getting warmer. (3. paragraph)

If you need any more explanations let me know.

Regards
Klaas

[bigdave60dog]

Yeah, Sorry about that!
The whole global warming discussion is one of my many pet rants.
I live on/in South Ronaldsay, Orkney.
On a small Island, our lives are affected by The Sea much more than most Coastal towns on the Mainland.
Changes due to "Global Warming" rather than the now politically correct term "climate change" are affecting The Sea around us three times as fast as they are on land. this is because "The Sea" is one large body of water surrounding land masses. rather than a number of land masses surrounded by water.
Therefore the temperature of The Sea has tendency to increase or decrease on a global scale where land temperature is affected by more local forces.
The overall temperature of The Sea IS rising on a global scale. This is affecting the climate on land. Generally speaking The Sea has "Global Warming" -or "Cooling as the case may be" causing Land to experience "Global Climate Change"
There is large body of financial and political interest in playing down the current and future effects of these global changes. Reports such as the one quoted find favour and so are giving a high profile by these interests. Whereas most thinking people can see what is happening with there own eyes.
Similarly it was plain to most that the developed world could not sustain economic growth by lending consumers more and more to carry on buying as means of achieving economic growth. Hence the financial crash.
In the same way most of us can see and understand that the global temperature is rising. Governments are planning for a future based on the effects of changes based on this. Yet there is still educated discussion about "Is it or isn`t it?" Surely the "grass roots" discussion should be based on the questions "How will it affect me and how can I best plan to make the most of it?"
There that`s me ranted for the day,
Dave

[Klaas Reißmann]

Hi Rob,

[...]it has happened soon after the industrial revolution in the West[...]

this is one of all the facts that make me wondering, if the global warming is really men made. If the start for global warming happened soon after the industrial revolution, one have to ask why the little quantities of CO2 (comparing to the quantities of today) made a remarkable warming up, but the huge quantities of today does not more in relation to it.

Another fact is that there was a global warming in the first half of the 19th century and after the time of about 50 years it was cooling down again (in the first half of the 19th century were a lot of insect species found in Germany that no one found again since than). No one would say, that this warming up was men made. But no one knows why the temperatures raised for about half a century.

Today we have a warming up and everyones opinion is, that this is men made. No one gives any reason a naturaly warming up and I don't believe in the theorie of men made warming up. A few million years ago Europe was far more south, dinosaurs lived in Europe and huge forrests were growing. There was a quantity of CO2 in the air that made trees and other plants grow much bigger than they do today. But if CO2 produces such a strong glass house effect temperatures must have been much higher in this area than they were.

I'm sorry I can't explain the way I loved to, but my English is not good enough for this. I just hope you get what I mean and what antagonisms I see not to believe in a warming up that is only men made. And I hope you get, why I don't believe that we are able to stop warming up, even if it is just because of our CO2 emissions. On one hand I don't believe that China will try to decrease its CO2-emissions, on the other hand I think Europe and North America wouldn't do it, even everyone is talking about it.

We loose the savings of emission by driving new cars with less CO"-emissions and by using new technologies for heating systems, new technologies to produce electrical power in private to the industrie raising its production volume each year. And it is eyewash to believe we save CO2, because we just let others polute the air for us to get the products we need.

So far I guess everyone living at the coast should be thinking about how long he can live there, because mankind is not interrested in doing anything against these problems. It is just nice to have a new reason to raise taxes...

Regards
Klaas