Azothius wrote:Good point about the diminished volume. And totally agree that there is a chance that a new record low could be set this year. Though I think its an overstatement to say that there is an excellent chance. As we all have witnessed, several of the past years seemed possibly headed for a new low that did not materialize. The ice cap has shown an unexpected resiliency. Thus far, its been the weather and not the state of the ice that has been the determining factor. Though as Dissident and Plantagenet point out, once that tipping point is crossed, it's game over.
Perhaps those here who are more well read than I can comment upon this (feigning my best science-speak): In complex systems, whether (social) political, economic, (geophysical) climatological, etc, as the system is going through a phase transition from one regime to another, there is an inherent self-perpetuating mechanism within the system that resists crossing the tipping point leading to the next regime. Not only do the same set of factors that maintained the system resist the disruption of the system, but new negative feedbacks come into play that reinforce the existing state even as positive feedbacks that would potentially lead to the new state are increasing. It is this struggle between the two sets of feedbacks that ultimately produces the non-linear, abrupt transition from one state to the next, rather than the system undergoing a smooth transition. [edit: For if the positive feedbacks overwhelm the negative, they will have amassed significant cumulative forces (or effects?) (or power?) during the standoff and are now free to unleash their full impacts.] Whether or not the system actually undergoes the phase transition is dependent upon which set of feedbacks prevail.
1. Don't beat up on me for sounding pseudo-scientific. Just trying to articulate something.
2. Where would I have encountered this concept? I can't recall.
3. Would love to hear everyone's thoughts about this as it applies the the arctic sea ice.
I agree with your comment completely.
As far as the observations on the nonlinearity of the evolution of these type of processes and the balance of negative and positive feedbacks, I won't pretend to be well read or have a strong science background, but I have believed this to be the case for a number of years now. Also, as Plantagenet, Dissident, and you pointed out once we pass a tipping point going back would be unlikely. It would require a new tipping point in the opposite direction, which considering current trends I don't see happening in our lifetimes. I believe this concept applies to a number of issues, including Arctic sea ice extent. I've read that, too, and, just like you, I don't remember where, but it sounds convincing to me and I am completely sold on the idea of this nonlinearity.
The Arctic sea ice could almost completely melt any year now. The necessary conditions are already there. A blue Arctic Ocean event will become increasingly likely with every passing year. I clearly remember scientists saying that this would NOT happen before the end of the century about a decade ago, maybe on one of the IPCC reports. I read that section out loud to my wife and couldn't stop laughing about it. I knew they were very wrong. All these Global Warming and Climate Change consequences are going to land on us like a ton of bricks much faster than anticipated.
Another consequence that is extremely likely to evolve nonlinearly is sea level rise. Some chunks of ice in Greenland or the Antarctic are going to fall into the ocean very fast raising sea level very significantly, and it will happen in hours, days, weeks, or months, not decades; it's a matter of when, not if. Most people are going to be extremely surprised when it happens.
