New Iceage? Much Evidence? - Global Cooling

[Iceberg]

Neither of those sources are particularly reliable.

However, ice ages don't develop universally across the globe so looking at the global temperatures reveals very little. Regional changes, particularly in the Northern Hemisphere would be the first place to look for evidence. Is the NH cooling? Are glaciers advancing? Is the Arctic ice increasing?

Sorry Jethro but this is a bizarre statement ice ages are global. see the defination below.

"An ice age or, more precisely, glacial age, is a generic geological period of long-term reduction in the temperature of the Earth's surface and atmosphere, resulting in the presence or expansion of continental ice sheets, polar ice sheets and alpine glaciers."

Global temperatures reveal everything about whether we are entering another Ice age.

If we assume we are talking about the little ice ages of the 1880's etc then yes these can be regional, but then again they are not ice ages.

Anyway if we look at northern hemisphere anomalies since say 1990 (could go back further but I deliberately didn't want to include the colder 70's and 80's even though it would make the point clearer.) we see a steady trend increasing despite any cyclical effects of NAO, ENSO, PDO, Solar etc. Sorry about the excel graph without too much info but it was easier than finding one of the net and the data was direct from source, happy for any other n.Hemisphere data to be posted though.

I think it's rather plain that Arctic ice is decreasing and I have yet to see a study that claims that n.Hemisphere ice sheets or glaciers are expanding.

So if anybody things we are entering a new iceage or even mini iceage then they are wrong IMO, a bit black and white from me, but the data is overwhelmingly against.

[jethro]

Sorry Jethro but this is a bizarre statement ice ages are global. see the defination below.

"An ice age or, more precisely, glacial age, is a generic geological period of long-term reduction in the temperature of the Earth's surface and atmosphere, resulting in the presence or expansion of continental ice sheets, polar ice sheets and alpine glaciers."

Global temperatures reveal everything about whether we are entering another Ice age.

If we assume we are talking about the little ice ages of the 1880's etc then yes these can be regional, but then again they are not ice ages.

Anyway if we look at northern hemisphere anomalies since say 1990 (could go back further but I deliberately didn't want to include the colder 70's and 80's even though it would make the point clearer.) we see a steady trend increasing despite any cyclical effects of NAO, ENSO, PDO, Solar etc. Sorry about the excel graph without too much info but it was easier than finding one of the net and the data was direct from source, happy for any other n.Hemisphere data to be posted though.

I think it's rather plain that Arctic ice is decreasing and I have yet to see a study that claims that n.Hemisphere ice sheets or glaciers are expanding.

So if anybody things we are entering a new iceage or even mini iceage then they are wrong IMO, a bit black and white from me, but the data is overwhelmingly against.

Perhaps the word I should have used was simultaneously rather than universally. However, universally is equally as valid, the equatorial regions are not as impacted as the Northern Hemisphere, not all things are equal in ice age climate changes.

The regional changes where first indications could be found would be glacial advance and increased polar ice levels - that is exactly what I said this morning and exactly what you say above. It's a bizarre statement from me, but a factual one from you - erm, why, how? Seems we're in agreement in our statements so why the disagreement?

Global temperatures wouldn't suddenly drop, the decline would be gradual, starting first with a levelling off - ice ages, mini or full scale take time, it doesn't happen in an instant. Regional changes would be apparent before global impact was really felt.

[Iceberg]

Sorry I still disagree looking for a leveling off of temps or declining temps in the N.Hemisphere as a sign of an impending iceage is meaningless, both of these things can happen and it means not a jot wrt the start of an iceage, I could say with almost certainty that 99% of the time that temperatures do drop in the N.Hemisphere or ice increases it does not lead to an ice age.

An iceage is usually triggered by global temps going below a certain line for a number of decades, if we want to look for an indicator of an impending ice age, then 100 years of falling temps (globally) would probably be the best start, this would by it's nature most likely lead to growing arctic ice and expanding glaciers.

[jethro]

Sorry I still disagree looking for a leveling off of temps or declining temps in the N.Hemisphere as a sign of an impending iceage is meaningless, both of these things can happen and it means not a jot wrt the start of an iceage, I could say with almost certainty that 99% of the time that temperatures do drop in the N.Hemisphere or ice increases it does not lead to an ice age.

An iceage is usually triggered by global temps going below a certain line for a number of decades, if we want to look for an indicator of an impending ice age, then 100 years of falling temps (globally) would probably be the best start, this would by it's nature most likely lead to growing arctic ice and expanding glaciers.

With respect, I think you're splitting hairs.

At no point did I say levelling off or declining temperatures in the Northern Hemisphere were signs of an impending ice age. I said if an ice was happening then the first signs would probably become apparent by regional changes, beginning with the polar region.

Ice age conditions advance as polar ice grows and glaciers advance.This process, over time, removes water from the hydrological cycle. This in turn alters the weather patterns and ocean cycles, as these changes occur (coupled with the increased albedo of the greater snow/ice cover) then the impacts become apparent further afield than the polar regions. Eventually all the world cools.

You seem to be under the impression that I support the idea of an impending ice age and that I am in agreement with Bastardi? I thought I made it clear that I don't consider him to be a reliable source. Waz is a new member who has joined in asking questions (by the way, brilliant Waz and welcome) - he says he's been learning by reading various sites including Ice Age Now and Bastardi. My suggestions of questions to ask (ice advance, glacial advance etc) were to encourage him to want to learn more and explore sources outside of those sites.

[VillagePlank]

Global temperatures reveal everything

No such thing as a 'global temperature'

Well, at least not one derived by the arithmetic mean. I guess, of course, you could be a super-intelligent being that can break the laws of physics and produce thermodynamics at a distance, but, on the balance of probability I must assume that you are not God.

I suppose you must also believe in the divination of average exchange rates (across currencies), and average phone book numbers?

Edited July 27, 2011 by Sparticle

[VillagePlank]

So if anybody things we are entering a new iceage or even mini iceage then they are wrong IMO, a bit black and white from me, but the data is overwhelmingly against.

Actually, the data suggests that after a period of massive warming the Earth hits it's maximum, and rather like clouds shedding precipitation quickly, the Earth sheds temperature quickly such that it returns to a very cold state. See Petit et al.

:blink:

Edited July 27, 2011 by Sparticle

[Gray-Wolf]

I tought Petite (et al) were being all Lovlockian with the 'settled state' continueing right into the period of negative forcings and then a 'snap change' into another 'settled state'?

The changes in the Arctic may well prove to be the 'snap change' to another 'settled state'?

[VillagePlank]

I meant their CO₂ forcing paper (1980's I think) with respect to the Vostok ice core analysis. Briefly discussed on this very thread, here.

Edited July 27, 2011 by Sparticle

[Iceberg]

Actually, the data suggests that after a period of massive warming the Earth hits it's maximum, and rather like clouds shedding precipitation quickly, the Earth sheds temperature quickly such that it returns to a very cold state. See Petit et al.

:blink:

Yes exactly my point the "earth sheds temperature quickly" i.e global cooling, so the first sign of a an ice age would be the earth cooling down quickly (quickly in these timeframes is 50-100 years. ! )

It's not the warming though that you look out for as an indicator of an impending ice age as this might still have 1000 years left but the rapid and global cooling

[VillagePlank]

Yes exactly my point the "earth sheds temperature quickly" i.e global cooling, so the first sign of a an ice age would be the earth cooling down quickly (quickly in these timeframes is 50-100 years. ! )

It's not the warming though that you look out for as an indicator of an impending ice age as this might still have 1000 years left but the rapid and global cooling

Yes, good point. The Vostok ice-core analysis suggests that Earth's maximum is between +2C..+4C. Where are we today? What do the IPCC predict?

Edited July 27, 2011 by Sparticle

[drgl]

So if anybody things we are entering a new iceage or even mini iceage then they are wrong IMO, a bit black and white from me, but the data is overwhelmingly against.

Sorry but what is that graph showing? There is no info on the axis??

Edited July 27, 2011 by drgl

[Methuselah]

So, we are still at the stage where there is absolutely zero evidence around, suggesting that an Ice Age is imminent? Very strange, IMO, given that so many folks feel able to categorically state that the Earth is currently cooling...when it isn't! At least, not unless those who 'know' it is [cooling] have reset their clocks again - from 1998 to 2010? :unsure:

[UV-RAY]

So, we are still at the stage where there is absolutely zero evidence around, suggesting that an Ice Age is imminent? Very strange, IMO, given that so many folks feel able to categorically state that the Earth is currently cooling...when it isn't! At least, not unless those who 'know' it is [cooling] have reset their clocks again - from 1998 to 2010? :unsure:

It's not cooling, but then again it's not warming. Temps have flatlined over the last few years, were they go from here is anyone's guess, but if solar predictions are right then we should see evidence for cooling within the next few years, albeit a small decrease.

Edited July 27, 2011 by Seven of Nine

[UV-RAY]

Some evidence of an impending ice age, as such.

Ice age threat should freeze EPA global warming regs The Examiner Op Eds Washington Examiner.htm

More of a political rant really.

Edited July 27, 2011 by Seven of Nine

[VillagePlank]

No such thing as a 'global temperature'

Well, at least not one derived by the arithmetic mean. I guess, of course, you could be a super-intelligent being that can break the laws of physics and produce thermodynamics at a distance, but, on the balance of probability I must assume that you are not God.

I suppose you must also believe in the divination of average exchange rates (across currencies), and average phone book numbers?

Bugger. It looks like I am some 4 years late to the party, here. Someone's already had that idea, and it seems to have already been rebutted. Still, thought I was onto something for a couple of days there

Edited July 27, 2011 by Sparticle

[Methuselah]

It's not cooling, but then again it's not warming. Temps have flatlined over the last few years, were they go from here is anyone's guess, but if solar predictions are right then we should see evidence for cooling within the next few years, albeit a small decrease.

I'll buy that, Seven of Nine.

[songster]

Bugger. It looks like I am some 4 years late to the party, here. Someone's already had that idea, and it seems to have already been rebutted. Still, thought I was onto something for a couple of days there

To be honest, it's confused enough not to need rebutting. Parts of your body are at different temperatures. No part of your body is at equilibrium with any other part, nor are you at equilibrium with your surroundings. You cannot therefore conclude that your body does not have a temperature, nor that fever / hypothermia are not identifiable medical conditions.

[Methuselah]

To be honest, it's confused enough not to need rebutting. Parts of your body are at different temperatures. No part of your body is at equilibrium with any other part, nor are you at equilibrium with your surroundings. You cannot therefore conclude that your body does not have a temperature, nor that fever / hypothermia are not identifiable medical conditions.

I was debating [internally] the likely paradox that viewing this issue from a non-Popperian paradigm might cause...So, over to you, Sparticle!

[VillagePlank]

To be honest, it's confused enough not to need rebutting. Parts of your body are at different temperatures. No part of your body is at equilibrium with any other part, nor are you at equilibrium with your surroundings. You cannot therefore conclude that your body does not have a temperature, nor that fever / hypothermia are not identifiable medical conditions.

Well, I didn't think so. :confused:

The premise is pretty straight-forward, I think: during calculations one must retain context (Claude Shannon's information theory) An arithmetic mean calculation requires that you add up all the temperatures of the world before you divide by the quantity of measurements. The first part of the calculation gives you a nonsensical number (context is lost) therefore the calculation is faulty.

What I missed is that that is not what is going on (CRU are perhaps guilty of mis-titling their charts - perhaps) Nobody is actually meaning to say this is the mean temperature of the Earth - it is the mean anomaly. Which makes sense.

I still think averaging intensive properties (temperature etc) is a very dangerous thing - but it's not what is going on in climate science.

BTW - your body does not have an average temperature that is meaningful - as you said, a body has different temperatures that are locally useful, but the global arithmetic mean isn't - perhaps the anomaly from the mean of your body is useful ...for instance let's say one part of your body is 37.5C, your heart, say, and an another part, the lobe on your ear is 4.5C. The average of the two numbers is 21C, room temperature, so one might be able to say that since your body is at room temperature you are effectively ... dead.

I was debating [internally] the likely paradox that viewing this issue from a non-Popperian paradigm might cause...So, over to you, Sparticle!

I prefer to be wrong only once a day, Pete!

Edited July 27, 2011 by Sparticle

[songster]

BTW - your body does not have an average temperature that is meaningful - as you said, a body has different temperatures that are locally useful, but the global arithmetic mean isn't - perhaps the anomaly from the mean of your body is useful ...for instance let's say one part of your body is 37.5C, your heart, say, and an another part, the lobe on your ear is 4.5C. The average of the two numbers is 21C, room temperature, so one might be able to say that since your body is at room temperature you are effectively ... dead.

Fair enough, let's talk about the temperature of the heart - the body's "core temperature". Would you accept that this is meaningful? If it goes up too much, you die. If it goes down too much, likewise. But what is that "core temperature"? It's nothing but the average of the left ventricle, the right ventricle, the auricles, and the blood contained therein. Surely it must therefore be meaningless, by your logic. So now let's say we only care about the temperature of the left ventricle. That is only an average of the temperatures of each individual cubic millimetre of heart muscle...

This is drivel! Temperature is an average. Inherently, and by definition. It is the averaged randomised kinetic energy of a group of particles. By your cockeyed logic, there's no such thing as temperature at all. Codswallop. You can average across one set of particles (your heart) just as validly as you can any other (the molecules in my cup of tea, the atoms in the sun, your car's windscreen, or the surface of the Earth). What matters is whether that average is useful. The planetary temperature plainly is useful: if it's changing, it tells you something about the net energy balance of the system. More localised temperatures are also useful, and likely more so in most cases - when predicting the likely future of Arctic ice, say, or deciding whether it's safe to get into your bath. The key is to use any given temperature measurement in the area for which it is useful. When assaying the global effects of greenhouse gas release, global temperature is one type of useful measurement.

I prefer to be wrong only once a day, Pete!

Ah, but you were wrong ten minutes ago, you were wrong nine minutes and fifty-nine seconds ago, you were wrong nine minutes and fifty-eight seconds ago... best average them together, at least that way you'll only be wrong once. :-p

Edited July 27, 2011 by songster

[Guest]

BTW - your body does not have an average temperature that is meaningful - as you said, a body has different temperatures that are locally useful, but the global arithmetic mean isn't - perhaps the anomaly from the mean of your body is useful ...for instance let's say one part of your body is 37.5C, your heart, say, and an another part, the lobe on your ear is 4.5C. The average of the two numbers is 21C, room temperature, so one might be able to say that since your body is at room temperature you are effectively ... dead.

I prefer to be wrong only once a day, Pete!

I think this shows how measurements by temperature alone can be misleading - temperature is merely a measurement of the level of heat and not the measure of the amount of heat which can be different.

In this case we could measure to total number of calories in the body and use this against the total number of calories in the ear lobe then average these two figures out then the answer would be very much different - so in fact you would not be dead after all.

[Guest]

Ah, but you were wrong ten minutes ago, you were wrong nine minutes and fifty-nine seconds ago, you were wrong nine minutes and fifty-eight seconds ago... best average them together, at least that way you'll only be wrong once. :-p

So would this be the difference between passé parfait and passé imparfait?

[VillagePlank]

Fair enough, let's talk about the temperature of the heart - the body's "core temperature". Would you accept that this is meaningful? If it goes up too much, you die. If it goes down too much, likewise. But what is that "core temperature"? It's nothing but the average of the left ventricle, the right ventricle, the auricles, and the blood contained therein. Surely it must therefore be meaningless, by your logic. So now let's say we only care about the temperature of the left ventricle. That is only an average of the temperatures of each individual cubic millimetre of heart muscle...

Is the temperature of the heart meaningful? Well, no. Since all of our hearts have different temperatures a single temperature average of the heart isn't meaningful at all. Did you think that it was? What is meaningful is how it changes over time ... by this thinking all you'd need to do is go into a hospital take one measurement, and hey presto! diagnosis. Anyone could be a doctor simply by measuring an average (of whatever you wanted) reading down a list of preferred values and dishing out the drugs on the list.

This is drivel!

Is this a soliloquy?

Temperature is an average. Inherently, and by definition. It is the averaged randomised kinetic energy of a group of particles. By your cockeyed logic, there's no such thing as temperature at all. Codswallop. You can average across one set of particles (your heart) just as validly as you can any other (the molecules in my cup of tea, the atoms in the sun, your car's windscreen, or the surface of the Earth). What matters is whether that average is useful. The planetary temperature plainly is useful: if it's changing, it tells you something about the net energy balance of the system. More localised temperatures are also useful, and likely more so in most cases - when predicting the likely future of Arctic ice, say, or deciding whether it's safe to get into your bath. The key is to use any given temperature measurement in the area for which it is useful. When assaying the global effects of greenhouse gas release, global temperature is one type of useful measurement.

OK, what's the spot average temperature of the Earth? Why is that, alone, useful? Why did the scientists go to all of the trouble of homogenising the series to a set of anomalies, and then average the anomalies and not the temperatures? That seems to be an awful lot of bother when, as you say - just scale up the arithmetic mean. Do you think these people are doing all of this extra work just for more funding? Or, perhaps, there's a good reason for it?

Ah, but you were wrong ten minutes ago, you were wrong nine minutes and fifty-nine seconds ago, you were wrong nine minutes and fifty-eight seconds ago... best average them together, at least that way you'll only be wrong once. :-p

And no doubt I will carry on being wrong for a very long time ...

Edited July 27, 2011 by Sparticle

[VillagePlank]

Fair enough, let's talk about the temperature of the heart - the body's "core temperature". Would you accept that this is meaningful? If it goes up too much, you die. If it goes down too much, likewise. But what is that "core temperature"? It's nothing but the average of the left ventricle, the right ventricle, the auricles, and the blood contained therein. Surely it must therefore be meaningless, by your logic. So now let's say we only care about the temperature of the left ventricle. That is only an average of the temperatures of each individual cubic millimetre of heart muscle...

This is drivel! Temperature is an average. Inherently, and by definition. It is the averaged randomised kinetic energy of a group of particles. By your cockeyed logic, there's no such thing as temperature at all. Codswallop. You can average across one set of particles (your heart) just as validly as you can any other (the molecules in my cup of tea, the atoms in the sun, your car's windscreen, or the surface of the Earth). What matters is whether that average is useful. The planetary temperature plainly is useful: if it's changing, it tells you something about the net energy balance of the system. More localised temperatures are also useful, and likely more so in most cases - when predicting the likely future of Arctic ice, say, or deciding whether it's safe to get into your bath. The key is to use any given temperature measurement in the area for which it is useful. When assaying the global effects of greenhouse gas release, global temperature is one type of useful measurement.

Ah, but you were wrong ten minutes ago, you were wrong nine minutes and fifty-nine seconds ago, you were wrong nine minutes and fifty-eight seconds ago... best average them together, at least that way you'll only be wrong once. :-p

Well at least someone likes your diatribe (the reputation point) I urge you to think again. It's really not that intellectually challenging. Nice to see you poke your head above the parapet once I admitted I was wrong. Easy, huh? Hey - you're a star. AKA troll.

[Snow Leopard]

Interesting article:

Link here