How unstable the climate can be

[mooncliff]

Because of changes in circulation in the north Atlantic, the Earth entered a 1,300 year ice age WITHIN MONTHS. An example of how unstable the climate can be and how warming can result in abrupt cooling.

http://www.newscientist.com/article/...in-months.html

Lots of interesting concepts if you have not heard of the Younger Dryas.

http://en.wikipedia.org/wiki/Younger_Dryas

[Dr.No]

The normal state of affairs is a far more unstable climate

Because of changes in circulation in the north Atlantic, the Earth entered a 1,300 year ice age WITHIN MONTHS. An example of how unstable the climate can be and how warming can result in abrupt cooling.

http://www.newscientist.com/article/...in-months.html

Lots of interesting concepts if you have not heard of the Younger Dryas.

http://en.wikipedia.org/wiki/Younger_Dryas

Nice to see someone speaking of climate instability instead of global warming. Thank you for that.

Tiring to almost always always hear about global warming instead of climate instability - in some places the average temperature may rise substantially, in many places it will increase moderately or not at all, while in some places the temperature is likely to fall.

The most important issue with regard to the climate is that it was exceptionally stable over the past 10,000 years. Go back millions of years, and one would be hard pressed to find a period where the climate was so abnormally stable. The normal state of affairs is a far more unstable climate.

Human civilization arose precisely during the past 10,000 years of abnormally stable climate. Regardless of whether the globe will warm, cool, or both, it appears a near certainty that the climate has now been pushed away from its temporarily stable period, and is returning to its normal chaotic state.

Let's see how civilization deals with a return to normal - something with which humans have never had any experience since prehistoric times. Would be unfortunate if civilization had to deal with a declining energy production at the same time.

Good luck to us - it appears we will very much need it (especially given that we seem not to bother planning farther ahead than perhaps a few months to a few years).

[Dr.No]

Re: The normal state of affairs is a far more unstable climate

I'm surprised no one seems interested in this topic.

[Starving Steve]

Re: How unstable the climate can be

These revelations about how unstable the natural climate of the Earth is, collectively refute the basics of the argument made by the man-made global warming bunch ( Greenpeace, Dr. Hansen at NOAA, Dr. David Sazuki in Toronto, the BBC, the UN, Al Gore, et.al. ) that man's activities have upset the planet's climate. But actually studying the history of climate on this planet, if man has had any affect upon climate at all, one could argue that man's activities have stablized the Earth's heretofore chaotic climate.

Since the scare-mongers in the man-made global warming group have generated public hysteria, it is up to them now to dis-prove that man's activities have stablized the Earth's climate. The climate data shows decades of relative stability, so why is man to blame for anything? It may well be that CO2 actually blankets the Earth and shelters the planet from caotic climate change---- that is what the data seems to show.

Science is supposed to go where the data leads to, and the climate data on this planet leads to dismissing the anthropogenic global warming hypothesis. Scientists had better be reviewing natural trends in the environment, especially trends on the Sun, to have any basis for predicting the Earth's climate in future years.

[Dr.No]

Re: How unstable the climate can be

These revelations about how unstable the natural climate of the Earth is, collectively refute the basics of the argument made by the man-made global warming bunch ( Greenpeace, Dr. Hansen at NOAA, Dr. David Sazuki in Toronto, the BBC, the UN, Al Gore, et.al. ) that man's activities have upset the planet's climate. But actually studying the history of climate on this planet, if man has had any affect upon climate at all, one could argue that man's activities have stablized the Earth's heretofore chaotic climate.

Since the scare-mongers in the man-made global warming group have generated public hysteria, it is up to them now to dis-prove that man's activities have stablized the Earth's climate. The climate data shows decades of relative stability, so why is man to blame for anything? It may well be that CO2 actually blankets the Earth and shelters the planet from caotic climate change---- that is what the data seems to show.

Science is supposed to go where the data leads to, and the climate data on this planet leads to dismissing the anthropogenic global warming hypothesis. Scientists had better be reviewing natural trends in the environment, especially trends on the Sun, to have any basis for predicting the Earth's climate in future years.

Would you be capable of entertaining the thought that an abnormally stable climatic period naturally arose (a chaotic system can easily have relatively short periods of apparent stability - there is nothing contradictory in that), and that what has been one of the most rapid increases in methane and CO2 in Earth's history (over the past 100+ years or so) may be the factor that disturbs this rare stable state, tipping it back in to the normally dominant chaotic state?

At this point, it is quite possible that no human action would be sufficient to return the planet's climate back to that profoundly beneficial (to human civilization) state.

[Ghent12]

Re: How unstable the climate can be

Would you be capable of entertaining the thought that an abnormally stable climatic period naturally arose (a chaotic system can easily have relatively short periods of apparent stability - there is nothing contradictory in that), and that what has been one of the most rapid increases in methane and CO2 in Earth's history (over the past 100+ years or so) may be the factor that disturbs this rare stable state, tipping it back in to the normally dominant chaotic state?

At this point, it is quite possible that no human action would be sufficient to return the planet's climate back to that profoundly beneficial (to human civilization) state.

I'm curious as to whether your second paragraph is a serious lamentation or an ironic one. I think it should be quite obvious to everyone now that any serious global effort of the sort required to combat AGW (given the assumption that it's real and is as the IPCC claims) will be several decades away, if not more than a century.

Even Europe is still increasing its CO2 emissions, and they're supposed to be the leaders in combating AGW. http://www.eea.europa.eu/pressroom/n...ses/GHG2006-en

Then take into account that absolutely no proposal being considered now will place any meaningful restrictions on India and China, and the significant (and currently growing, according to Rasmussen) political opposition in the US, and you wind up for a recipe for inaction for decades; when in fact we must absolutely stop GHG emission for decades, as in an 80% or greater reduction, in order to make a meaningful impact against AGW.

Those facts really make efforts against AGW rather moot, I think. The issue of climate instability is probably a greater threat.

I would contend that there are a few other things facing the species as a whole that are far more threatening potentially than either AGW or climate instability. Aside from nuclear exchange and killer asteroids, there's also the overdue magnetic pole shift which will leave the Earth defenseless against harmful radiation for an unknown period of time--hopefully very quickly. While species have survived it in the past, there's no way of knowing the extent of its effects on our modern society.

[c1ue]

Re: How unstable the climate can be

The article is amusing: it says that the Europe mini-Ice Age was due to a lot of cold fresh water getting dumped into the North Atlantic causing a Gulf Stream slowdown.

This itself is a feedback mechanism against warming.

But then unsurprisingly:

Some climate scientists have suggested that the Greenland ice sheet could have the same effect if it suddenly melts through climate change, but the 2007 report of the Intergovernmental Panel on Climate Change concluded this was unlikely to happen this century.

I should also note that the Greenland Ice sheet melting/Gulf Stream slowdown was specifically called out by Bill Nye in his debate vs. Dr. Richard Lindzen - posted in the long climate debate thread.

So which is it?

Are the glaciers going to melt due to catastrophic AGW and drop temperatures into an Ice Age (and reverse warming)?

Or are the glaciers not going to melt and warming not going to happen as catastrophically as expected?



But this paper's conclusion isn't rocket science nor even new. The Tamboura volcano explosion changed climate within months and that is in the records - clearly global climate changes can and have occurred within short periods of time.

[Dr.No]

Re: How unstable the climate can be

The article is amusing: it says that the Europe mini-Ice Age was due to a lot of cold fresh water getting dumped into the North Atlantic causing a Gulf Stream slowdown.

This itself is a feedback mechanism against warming.

But then unsurprisingly:



I should also note that the Greenland Ice sheet melting/Gulf Stream slowdown was specifically called out by Bill Nye in his debate vs. Dr. Richard Lindzen - posted in the long climate debate thread.

So which is it?

Are the glaciers going to melt due to catastrophic AGW and drop temperatures into an Ice Age (and reverse warming)?

Or are the glaciers not going to melt and warming not going to happen as catastrophically as expected?



But this paper's conclusion isn't rocket science nor even new. The Tamboura volcano explosion changed climate within months and that is in the records - clearly global climate changes can and have occurred within short periods of time.

The theory speaks of localized cooling (more specifically, continental areas on the eastern and western sides of the North Atlantic, extending inland several hundred miles from the coasts if I've understood correctly). At the same time such a localized semi-ice age took place, the planet as a whole could feasibly continue to undergo a significant increase in mean temperature. There is no contradiction here once you look at the details rather than mainly the headlines.

[c1ue]

Re: How unstable the climate can be

The theory speaks of localized cooling (more specifically, continental areas on the eastern and western sides of the North Atlantic, extending inland several hundred miles from the coasts if I've understood correctly). At the same time such a localized semi-ice age took place, the planet as a whole could feasibly continue to undergo a significant increase in mean temperature. There is no contradiction here once you look at the details rather than mainly the headlines.

Please post where this theory is explained - I'd like to understand if this is an actual thought process as opposed to a rationalization.

I have yet to hear of localized hot spots elsewhere in the world coincident with any of the Ice Ages in Europe.

I have, however, seen attempts at removing things like the Medieval Warm Period - which has been documented in places as disparate as Greenland and the Peruvian Andes - hence the request.

[Dr.No]

Re: How unstable the climate can be

Please post where this theory is explained - I'd like to understand if this is an actual thought process as opposed to a rationalization.

I have yet to hear of localized hot spots elsewhere in the world coincident with any of the Ice Ages in Europe.

I have, however, seen attempts at removing things like the Medieval Warm Period - which has been documented in places as disparate as Greenland and the Peruvian Andes - hence the request.

Not just a rationalization, though the likelihood of this happening within the next few years or decades may be minimal. You can find a bit of information on it here:

http://en.wikipedia.org/wiki/Shutdow...ne_circulation

[c1ue]

Re: How unstable the climate can be

Not just a rationalization, though the likelihood of this happening within the next few years or decades may be minimal. You can find a bit of information on it here:

Given that the Wikipedia article mentions the New Scientist article in question - this is a circular reference.

Even within the Wiki article: all effects from what I can see are as a result of climate model simulations; given that most of these models don't even bother with ENSO - with the ones that do not apparently doing it well - it is hard to see how a localized North Atlantic projection from the same model can be relied on.

If the large ENSO effect is ignored, how can the smaller Atlantic ENSO equivalents be taken into account?

So again, please provide a more clear delineation of this concept.

[Dr.No]

Re: How unstable the climate can be

Given that the Wikipedia article mentions the New Scientist article in question - this is a circular reference.

Even within the Wiki article: all effects from what I can see are as a result of climate model simulations; given that most of these models don't even bother with ENSO - with the ones that do not apparently doing it well - it is hard to see how a localized North Atlantic projection from the same model can be relied on.

If the large ENSO effect is ignored, how can the smaller Atlantic ENSO equivalents be taken into account?

So again, please provide a more clear delineation of this concept.

The wikipedia article lists several sources; the idea was that you could start researching the topic there if you wanted to understand it better.

The general idea is simply that if enough fresh water (lighter than saltwater, so it stays on the surface for quite some time until it eventually mixes with the saltwater) enters the North Atlantic, it may slow or entirely interrupt the thermo-haline circulation.

It is this circulation that brings heat from the Mexican Gulf to areas much farther north, particularly important to northern Europe (and at least to some extent the U.S. North-East).

An interruption of the current would then lead to a cooling of these areas, while there is no particular reason that it necessarily should have any significant impact on the Earth's overall temperature trend (although, perhaps, if these areas were to freeze solid and be covered in snow and ice all year, more sunlight would be reflected than absorbed due to the increased albedo).

[Starving Steve]

Re: How unstable the climate can be

Just like with creationism or creation science, the AGW bunch ( the anthro-pogenic global warming bunch ) keep stretching and twisting and pre-selecting the data to fit their theory. That kind of science is known as "junk science".

The burden of proof is now on the AGW bunch: Why are global sea levels not rising very much? Why are other explanations for climate change dismissed? Why is the current cooling in the Earth's climate since 1998 dismissed? Why didn't higher levels of CO2 in the Earth's atmosphere in the past bring about the global warming that they now predict? Why does dirt and dust in the atmosphere from mankind's activities not cool the Earth? Why is the effect of changes in the Earth's surface (urbanization, desertification, deforestation, et.al.) over-looked in their modelling? And how could glacial meltwaters have had a profound effect upon Earth's climate in the past, yet strangely not in the modelling of the future climate of Earth?:rolleyes:

A valid model in science is supported by criticism. The valid model provides the best and most economical explanation possible. Criticism of the model is never dismissed, rather it is encouraged because criticism strengthens the valid model.

No issue is ever "settled" in science because science is not a belief system. Yet the AGW adherents demand that debate on the subject now be closed, as if the issue is (to use their word) "settled".

An erroneous model in science is re-worked or thrown-out entirely by the process of scientific criticism. The AGW hypothesis, articulated by Al Gore, is not standing-up to scientific criticism and needs to be re-worked. :rolleyes:

[Dr.No]

Re: Now we are back to tired global warming theory complaints (again)?

Just like with creationism or creation science, the AGW bunch ( the anthro-pogenic global warming bunch ) keep stretching and twisting and pre-selecting the data to fit their theory. That kind of science is known as "junk science".

The burden of proof is now on the AGW bunch: Why are global sea levels not rising very much? Why are other explanations for climate change dismissed? Why is the current cooling in the Earth's climate since 1998 dismissed? Why didn't higher levels of CO2 in the Earth's atmosphere in the past bring about the global warming that they now predict? Why does dirt and dust in the atmosphere from mankind's activities not cool the Earth? Why is the effect of changes in the Earth's surface (urbanization, desertification, deforestation, et.al.) over-looked in their modelling? And how could glacial meltwaters have had a profound effect upon Earth's climate in the past, yet strangely not in the modelling of the future climate of Earth?:rolleyes:

A valid model in science is supported by criticism. The valid model provides the best and most economical explanation possible. Criticism of the model is never dismissed, rather it is encouraged because criticism strengthens the valid model.

No issue is ever "settled" in science because science is not a belief system. Yet the AGW adherents demand that debate on the subject now be closed, as if the issue is (to use their word) "settled".

An erroneous model in science is re-worked or thrown-out entirely by the process of scientific criticism. The AGW hypothesis, articulated by Al Gore, is not standing-up to scientific criticism and needs to be re-worked. :rolleyes:

Now we are back to tired global warming theory complaints (again)? The main point here was climate instability, not whether it will get hotter or cooler in East Sooke, BC.

A very large change in the composition of the atmosphere is likely to destabilize the climate - especially given that the normal state of the climate is one of tremendous instability (the past 10,000 years having been a rare period of exceptional calm).

[mooncliff]

Re: How unstable the climate can be

Yes, I brought this topic up not so that we can come to a conclusion about any aspect of climate, but so that everyone would look at some of the concepts and perhaps get an inkling of just how complicated climate is. Even a single aspect like the albedo of the Earth can lead to many fascinating hours of reading.

I also brought it up because something like the onset of an ice age in a single year would be the greatest human and economic disaster in history. Literally billions dead. I do not think that will happen soon, but it will in the future at some point. We could have a supervolcano eruption, but we cannot at this point control things like that. We CAN control the gases that we are injecting into the atmosphere, the albedo of our roofs, deforestation, and perhaps even bioprecipitation. http://www.bbc.co.uk/iplayer/episode...precipitation/

I have a Ph.D. in a related field, which of course does not mean that one is right (in fact, most people in the graduate school department were perfect idiots), but it does mean that I can say that I have spent several thousand hours on these topics, and I can assure you they are fascinating... there really is a lot to see. (And that was just about the Earth; the other planets teach other, even more amazing things.)
I no longer work in this field, so have no attachment to what I learned. In fact, the last few decades are a perfect illustration of "Science is the process of learning to be less wrong."

I think the climate has been unusually warm for the last 10,000 years because we cut down a lot of the trees and altered the albedo of the Earth. This was the first anthropogenic global warming.
It is not a good idea to inject so much carbon dioxide into the atmosphere when we do not know what that will do.
The entire arctic is melting, and this has happened suddenly in the last few decades. We will be very unhappy if the melting causes drastic changes in the circulation of the oceans.

And if you think that something like the Younger Dryas requires a huge glacial lake to burst in Canada...
http://www.newscientist.com/article/dn8398