Hi Mark
We cant, but we can make an educated guess by looking at what are known in ecology variously as alternative stable states, regime shifts, catastrophic shifts and other names. See for example work by Scheffer, Carpenter, Folke, Moss.
An environmental driver exists (might be steadily increasing nutrient concentrations (or CO2)), and the system maintains itself regardless. But pressure is building up, and suddenly it flips into a completely different state. If the environmental driver is taken back (at great expense and difficulty) to where it was when the system was in a desirable state, the system doesnt change back. Reinforcing stabilising mechanisms hold it in the new state (just as they did in the previous state, which was why it didnt change smoothly and is thus called non-linear). With some ecosystems, e.g. shallow lakes, subtle signs can be seen that it might flip soon (Brock & Carpenter paper is good), but we know about these because it has been seen many times. We can see signs in the planetary ecosystem (Arctic and Antarctic ice, Amazon, deserts etc) that we are probably nearing a flip, but this has not been witnessed before, and a lot is unknown. What is will be like afterwards is pretty unknown too, but sure as cheese is cheese, we wont like it, and it is hardly likely to be conducive to the sort of life we know. Unprecedented mass extinctions are predicted by some.
Preventing the flip is the top priority, thats why some people are prepared to take a few lesser risks to avoid it.
I Hope that helps, T
From: Mark Levene [mailto:[log in to unmask]]
Sent: 11 May 2011 13:53
To: Barker, Tom; [log in to unmask]
Subject: Re: Actic Council meeting on Thursday - Scientists for Global Responsibility - Emerging technologies: are the risks being neglected? 21 May 2011
Tom,
question;
if we can't 'know' how close we are to the 'flip' how can we 'know' the outcome of "some sort of measured geoengineering project" ?
mark
on 11/5/11 11:22 am, Barker, Tom at [log in to unmask] wrote:
In that case, you might as well have my reply to her. Tom
I agree with the precautionary principle of course, but we are already artificially manipulating the climate, and not trying to direct it to benign ends. We dont have time to ensure everything is safe as it can possibly be before we embark on some sort of measured geoengineering project. For one thing, that sort of knowledge can never be known, and for another, there is hysteresis in the system, and we cant know either what the result of a flip would be or how close we are to one. What we do know is that we would not be able to return to comparative stasis once the flip has occurred. And what we are pretty sure about is that we are hurtling towards that tipping point now, blindly. That seems to me to be the greater risk.
I came across this quote from Churchill the other day. You might wish to consider it in the light of climate change.
They go on in strange paradox, decided only to be undecided, resolved to be irresolute, adamant for drift, solid for fluidity, all-powerful to be impotent
Owing to past neglect, in the face of the plainest warnings, we have entered upon a period of danger. The era of procrastination, of half measures, of soothing and baffling expedience of delays, is coming to its close. In its place we are entering a period of consequences We cannot avoid this period, we are in it now - Winston Churchill November 12, 1936
Tom
From: Discussion list for the Crisis Forum [mailto:[log in to unmask]] On Behalf Of Mark Levene
Sent: 11 May 2011 13:21
To: [log in to unmask]
Subject: FW: Actic Council meeting on Thursday - Scientists for Global Responsibility - Emerging technologies: are the risks being neglected? 21 May 2011
from Tessa Burrington
but extremely relevant to us all.
mark
From: [log in to unmask]
To: [log in to unmask]
Subject: RE: Actic Council meeting on Thursday
Date: Tue, 10 May 2011 22:58:16 +0100
I am on the Crisis Forum mailing list. I thought you might be interested in the following conference - if you think it might be relevant. I will leave it to you to decide whether to post on the forum.
http://www.sgr.org.uk/events/emerging-technologies-are-risks-being-neglected
Emerging technologies: are the risks being neglected?
SGR Conference and AGM 2011
Saturday 21 May 2011
10.00 to 16.00
Alan Baxter and Associates Gallery, 75 Cowcross Street, London EC1M 6EL
Registration now open
New emerging technologies are being developed rapidly, especially as greater commercialisation of academic research is being emphasised to help deal with current economic problems. Many potential environmental, security, health and other benefits are being claimed for these technological developments. But are narrow priorities - especially economic ones - driving out careful examination of the claimed benefits and due consideration of risks? Are our political, economic and social structures managing to deal with the complexities that emerging technologies raise? Are alternative solutions for dealing with environmental and social problems being given proper consideration?
Scientists for Global Responsibility - Emerging technologies: are the risks being neglected?
Programme
10.00 Registration and Coffee 10.25 Welcome
Dr Stuart Parkinson, Executive Director, Scientists for Global Responsibility
10.30 PLENARY SESSION
Geo-engineering the Climate
Professor Joanna Haigh, Imperial College London Pdf of abstract and biography
Robots on the Battlefield: Ethical and Humanitarian Implications
Professor Noel Sharkey, Sheffield University Pdf of abstract and biography
Emerging Technologies and Risk: the Social, Cultural and Political Dimensions
Dr Bronislaw Szerszynski, Lancaster University Pdf of abstract and biography
12.45 Lunch
13.30 POSTER SESSION
The event will also include a poster session covering areas such as biotec