Wow Jonathan!  I have no evidence to support or refute that, but it is a very interesting idea. What do the physicists say?
Intuitively (not always a good guide I admit), I would say that the earth system will be different from a purely physical response. That is because physics, and chemistry too, however dynamic and amazing they are, and you only have to see a recent Horizon-type programme to be impressed, are physical responses that seek equilibrium.  Think of some dust from the moon (grey), Mars (brown), Venus (yellow) etc. etc.  That's all there is there. Add biology, and you get all the wonders of nature, and the tip of that iceberg is illustrated brilliantly by the likes of David Attenborough.  Life is incredibly complex, more so even than physics and chemistry, because it uses them to exploit for resources, and expands their capacities. Ecology, as a descriptor of life, identifies patterns that work in nature. The alternative stable states model explains a common but not universal dynamic that occurs where ecosystems are under stress from an external driver. Buffering mechanisms reinforce the existing state even under extreme pressure. A single suitable shock can cause the system to flip to another state where new buffering mechanisms will form to reinforce it and prevent it from returning to the prior state, even when the external pressure is removed.  This is the real danger of a global 'flip'. There is no guaranteed way back. What are the buffering mechanisms of the present Earth state?  I would say the ocean system, total area of wild nature, total area of peat/tundra etc.
Earth, as a biological system, seems more likely to follow biological patterns as described by ecology than it does a purely physical system. That said, the atmosphere is dominated by physical dynamics, so I'm open to ideas, but am not qualified to comment on it.

I think the 2 degree point is a stab at the point of no return. We should be aiming for much lower. We'll need some sort of geoengineering to get there, on top of adopting low-carbon lifestyles. We've geoengineered the wrong way (burning fossil carbon) for too long.

Cheers, Tom

________________________________________
From: Jonathan Ward [[log in to unmask]]
Sent: 13 March 2010 22:35
To: Barker, Tom
Cc: [log in to unmask]
Subject: Re: Climate change and eco-collapse

Tom and Brian,

I am not entirely sure of the processes you are describing here, but is
it fair to compare the argument to Earth Systems being analogous to
phase transitions in physics?

Could the climate mirror, let's say, the phase transitions of water
(purely analogous, what with water being somewhat integral to our
climatic systems). This is pure conjecture as I write, and I'll have to
go away and think about it, but let's say we are approaching the energy
in the climatic system that corresponds to the latent heat required to
move beyond a co-existence of two (or more) climate states, and we
change phase into a new state (i.e. like the enthalpy of vaporisation).
This new state could exist at the temperature we found previously, but
the energy put into the system has pushed through the phase transition.
In the case of water at vaporisation, we can have water at 100C, then as
the water absorbs enough energy, it overcomes the intermolecular forces
and atmospheric pressure, and becomes a gas. These then co-exist for a
while in a ratio that will gradually see increasing gas levels, then
just gas if the system of water has absorbed enough energy.

A spot of man-flu is somewhat blurring my thoughts, but the point I am
wondering about is whether the so-called Earth systems and our climate,
in the context of tipping points, can be seen in energetic terms, in the
same manner as we consider the ability for water to co-exist in
different phases until energy pushes it through a phase transition. This
also relates to entropy, but I fear I must do some back of the envelope
scribblings to wonder how it applies to my analogy.

So, the crux of my argument, is the 2 degree/tipping-point idea, more
valid in terms of some other parameter which move the climatic systems
as whole, or perhaps individual ones, into another 'phase' or stable
state? More valid the simply talking about one of the many forms of
temperature average that we can measure (atmospheric, oceanic, SST,
land, global average, 5/10/50/100 year average and so on), or even
perhaps the CO2 or GHGe parameters?

I don't know how far the analogy works in terms of reversing the phase
transitions. Clearly, our climate has moved between states over time,
but we are changing the mixture of parameters, and the timescales
involved, render the transitions as effectively irreversible on our
timescales.

I'm fairly sure this must have been considered and modeled elsewhere, so
if anyone has any information, please point me in the right direction!

Whilst I am on the topic of entropy, John Gray's review of Jeremy
Rifkin's Empathic Civilization is in today's Guardian
http://www.guardian.co.uk/books/2010/mar/13/empathetic-civilization-jeremy-rifkin-climate
. He tries to argue that empathy is no match for entropy.
I also spotted a paper which may be of interest
http://www.springerlink.com/content/9476j57g1t07vhn2/fulltext.pdf
(apologies if someone recently sent this around, I can't remember how I
came across it). The title is Are there basic physical constraints on
future anthropogenic emissions of carbon dioxide? .

Best wishes

Jonathan



Barker, Tom wrote:
> Brian
>
> I'm not sure what your agument is. I never said I was 'sure' of anything, but the evidence we have of how alternative stable states work (read Marten Scheffer and Steve Carpenter for example if you want to see the deeper theory) points to the need for a foward switch in order for the 'buffering' mechanisms' of the prevailing state to be overcome.  Your examples e.g. the jellyfish, are of buffering mechanisms. The new, degraded state in turn forms it's own buffering mechanisms, which reinforce the conditions of the new state.
> Having said this, we do not know for sure that the global system is subject to alternative states, i.e. tipping points might not even apply (there are other common dynamics), and in any case, there are a great many eco and other dynamic systems, each of which will change according to its own dynamics, some of which will be sudden as they cross some unknown threshold.
> The point is that we cannot make assumptions about what will happen; only try to discern probabilities.
> One thing is certain: we have definitely passed the point where talking and calculating represent the best use of our time. Now is the time to act, so as you succinctly point out, 'plant trees like there's no tomorrow'.
>
> Cheers, Tom
>
> ________________________________________
> From: Brian Orr [[log in to unmask]]
> Sent: 13 March 2010 12:38
> To: Barker, Tom
> Cc: [log in to unmask]
> Subject: Re: Climate change and eco-collapse
>
> Tom,
>
> I don't know how you can be so 'sure'.
>
> I have a respectable understanding of 'control theory' which is
> essentially the underpinning mathematics of dynamic systems - which,
> of course, includes ecological systems - and economic ones, as well.
>
> But without getting into the maths - which would leave me showing how
> old I was - but names like Nyquist and Laplace have not been
> completely relegated to the dustbin, I'm sure - take the collapsed eco-
> system off West Africa which was once a rich fishing area. Now it's
> become so over-fished that jelly-fish have taken over and there don't
> seem to be enough predators to shift the eco-system back to its
> previous state - and one can presume the excessive numbers of jelly-
> fish help to maintain the new balance - possibly by preying
> rapaciously on the fry of any big fish that succeeds in breeding.
>
> Or take the hare/lynx ecosystem in North America - a simplified eco-
> system because of the barren conditions. Here the wild fluctuations
> between the numbers of hares and lynxes is inherent in the simplicity
> of the system: lots of hares and the lynxes can multiply 'to their
> hearts content'. But the hares can't do this for ever because their
> food supply is limited. Sure enough, the lynxes get to population
> levels that make it increasingly hard for the hares to survive and the
> hare population then experiences a severe crash - with the lynx
> population following just as rapidly shortly after. The system is on
> the edge of instability - and is open to being destroyed by some
> external factor - such as climate change - that tips the system into
> too violent a fluctuation with the hordes of lynxes 'succeeding' in
> killing off the last hare - or hordes of hares dying of starvation
> because of the ultimate consequences of the last lynx dying as the
> natural fluctuation finally hits 'bottom' for the lynxes.
>
> Almost completely separate from this ecological dimension is man's
> activities in altering the 'parameters of the globe', with possibly no
> 1 being 'carbonising the atmosphere'. This on its own if not stopped
> is definitely going to tip the world's climate system into a new high
> temperature state which will be almost totally inimical to life and I
> would assert that it is not possible to say this hasn't already started.
>
> When you add in that man's interference in so many other substantial
> ways in the 'efficient operation' of the world's eco-systems, the
> persuasiveness of the contention that even if we stopped adding to our
> 'interferences' now the process of destabilising the planet which
> we've started will continue apace borders on the overwhelming.
>
> Conclusion: stop living as we are now and plant trees like there is no
> tomorrow. ('cos there won't be unless we get cracking now.)
>
> Brian Orr
>
> On 13 Mar 2010, at 08:10, Barker, Tom wrote:
>
>
>> Hi folks
>>
>> It is unlikely that we have already passed the 'tipping point', I'm
>> glad to say.  In nature where systems have alternative stable
>> states, a driver for ecosystem change (e.g. increasing
>> fertilisation) increases pressure on the system, making it
>> increasingly vulnerable to change, but it doesn't cause it to pass a
>> tipping point.  That requires another, separate, usually physical
>> cause (known as a 'forward switch'). Human society is doing
>> everything it can to increase the vulnerability of the global
>> ecosystem, but we don't know whether it (we) is throwing the forward
>> switch far enough yet.  Incidentally, my guess is that the biggest
>> forward switch we have is habitat loss.
>>
>> If you want to read an excellent explanation of the alternative
>> stable states hypothesis, it is explained very clearly in a book
>> called "The Broads, the People's Wetland", by Brian Moss, Collins
>> New Naturalist. Probably in your university library.
>>
>> Cheers, Tom
>>
>> ________________________________________
>> From: Discussion list for the Crisis Forum [[log in to unmask]
>> ] On Behalf Of Brian Orr [[log in to unmask]]
>> Sent: 11 March 2010 11:31
>> To: [log in to unmask]
>> Subject: Re: Climate change and eco-collapse
>>
>> The 2 degree figure has little meaning in that it is supposed to be
>> the temperature where we are 'probably' poised to hit THE tipping
>> point (or accumulated series of tipping points) where the system
>> 'takes over' and humans will have lost control of the global warming
>> process.
>>
>> But it is pretty clear that it is 'probable' that we have already
>> passed the tipping point, and all we can do is prepare for the time
>> when this becomes undeniable and 'mankind' finally agrees to one final
>> desperate lurch towards massive de-carbonisation in the hope that we
>> can pull back from the brink.
>>
>> But what we can do right now is climb aboard the parallel eco-
>> bandwagon which on its own provides a strong enough case for us to put
>> into reverse the planet-destroying activities that currently pre-
>> occupies homo sapiens: how much biodiversity loss, resource loss,
>> water and food shortages do we need to experience before we are
>> totally convinced our current modus vivendi has to be reversed - and
>> very, very quickly.
>>
>> This is not to say we abandon the case for urgent appraisal of our
>> approach to 'proselytising climate change'. It just means there is
>> another equally powerful reason for fundamental change which requires
>> virtually identical actions as does confronting climate change.
>>
>> Brian Orr
>>
>> On 11 Mar 2010, at 10:20, Chris wrote:
>>
>>
>>> On a related note, which I only discuss because I think it will be
>>> of interest to crisis-forumers, I am currently finishing off some
>>> interviews with some of the most prominent climate scientists about
>>> the value-laden nature of the 2 degree limit. This is an important
>>> issue I believe because this target defines the policy debate. What
>>> I am encountering is scientists telling me that it is a value
>>> judgement, that the numbers are meaningless, and perhaps the whole
>>> language of targets is meaningless. Then I am seeing their articles
>>> in scientific journals claiming two degrees as science. This is
>>> importangt because a) I don't believe the language of limits has any
>>> relevance or use in the cc debate and b) claiming the target as
>>> scientific fact masks the idea as a value judgement, a value
>>> judgement made by a tiny few in the name of the many.
>>>
>>> I conclude, in terms of where now for climate science, that science
>>> has told us all it can usefully tell us about cc and we need to move
>>> on to the real issues, the political, cultural and ethical
>>> dimensions of the debate.
>>>
>>> Chris
>>>
>>> Alastair McIntosh wrote:
>>>
>>>> Good comment by the BBC's Richard Black here on the forthcoming
>>>> IPCC review:
>>>> http://www.bbc.co.uk/blogs/thereporters/richardblack/2010/03/climate_review_seeks_detatchme.html#comments
>>>>
>>>> Alastair.
>>>>