: : Gee, read the letter I posted here on 24/12/99. The evidence has been studied by the peer group; and the overwhelming consensus is that global warming is occurring and constitutes a real threat to large sections of humanity. The three largest atmospheric research organisations in the world are unanimous in their findings and are confident enough about them to say so on the world stage.
: Lets proceed from this assumption then - that mankinds activity does affect climate, and is *contributing* to a current upward trend. As the letter said ; "The critical point is that we continue to see confirmation of the long-term warming trend. Scientists on both sides of the Atlantic are carefully looking at all of the evidence and using it to refine our understanding of global climate." i.e. they think it does, with great confidence, but they're not sure about how much, how long.
This is about as close as a scientist will get to making firm statements; it sent some pretty interesting shockwaves through the community.
(Modern 'big' science is so wary of humiliating itself through confident predictions that they've refined fence-sitting into an art; Pons and Fleischmann's cold fusion fiasco is still held up to junior scientists as an example of What Not To Do.)
Given the potential implications, these three scientists state the possible effects on humanity very clearly;
"At the same time, because of our past and ongoing activites, we must start to learn to live with the likely consequences - more extreme weather, rising sea levels, changing precipitation patterns, ecological and agricultural dislocations, and the increased spread of human disease.
Our agencies are doing their part to provide the best possible data, understanding and forecasts for policy-makers as they deal with these difficult issues. Ignoring climate change will surely be the most costly of all possible choices, for us and our children."
: I did think it disregarded dramatic climate changes in the past. Are you familiar with those antartic ice 'tubes' which read back 100,000s of years and suggest that sudden (within a few years/decades) climate change has been the norm for our planet
Yeah, but these were natural changes; not man-made ones. What those three said clearly was that this was man-made; that it could not be explained any other way.
Ancient Antarctic ice-core records show that sudden climatic change is recorded but highly unusual; the Earth's mean surface climate has not changed more than +/- 1 degree C throughout all of recorded human history; but since 1976 it has increased 0.5 degrees C and is still increasing; the most up-to-date models predict a mean global rise of 2 degrees C or more by the end of next century.
Sudden change can occur; but the defining mark of the recent rise is that it cannot be explained without factoring in human influence.
: I also think that association drawn between solar events and climate change should *not* be cast aside by environmentalists eager to 'save the planet'.
It isn't; but the work of the Copenhagen team who postulated it originally now freely admit that their results weren't as significant as they first thought; it's a factor, but not as significant as human effects.
: As an opportunity to understand how climate works all these factors are important.
Of course, which is why climate science is a valuable and vital study; and why the back-to-nature brigade aren't actually solving anything by insisting that humanity go back to the Stone Age. It's only by understanding the mathematics of the climate system that we can make vaguely accurate predictions.
: Anecdotally - some 'environmentalists' I have known of seem to think that shutting down factories and imprisoning people who use CFCs will 'make everything ok' and they dont really care about the extent of the 'injury' or the cost-benefit of various activities - they just want blood now! I trust this is not typical of an 'environmentalist'.
There are many people who would abuse the term; some would accuse me of abusing the term; in that I believe in the usefulness of technology.
I think that the environment is something we should maintain as carefully as possible; not necessarily in a 'virginal' state; that state is long gone (if it ever existed); but in a state that continues to support a wide diversity of life whilst also providing raw materials to live by. It may be that such a state is incompatible with the current way of life; I think it is; but I don't think regression to a previous state or refinement of the current state are a real solution either.
: So...what steps should be taken? Has there been any evaluations of possible effects other than doomstering about disease, complete with emotive warnings about 'our children'?
OK. Well, the costs required to limit damage due to rising sea levels are estimated at $70 trillion over the next 50 years; this would doubtless be too high a price to pay; so I think eventual abandonment of low-lying land will be the only sensible reaction; goodbye to the Netherlands, Egypt, New York and Florida.
Secondly, vector-borne disease. Human population currently living in malarial zones: 45% - this is predicted to rise to 60% over this century (felt weird typing that!) - any public health programmes coping with vector-borne diseases like malaria and trypsomaniasis will need to expand their budget by 33%, as well as making backup plans for days lost at work due to things like malarial fits; large parts of the Southern and Central USA are likely to be hit by this, as are places like Spain, Italy and Southern France.
Thirdly, extreme weather events. Like I've said, the weather is a thermodynamic system; it follows the Boltzmann distribution.
(There's a funky little Java applet which demonstrates this; you can find it here - if you keep the mass and number of molecules in the simulation constant but raise the temperature, the number of high-energy particles increases.)
Similarly, the higher the number of high-energy particles in a thermodynamic system, the more likely that high-energy reactions and processes are to occur. In other words, raise the temperature and you're more likely to get individual short-term extreme weather conditions, because the overall long-term energy of the system is higher.
The average number of Atlantic hurricanes yearly has increased by a total of 33% over the last 30 years; we can expect to see this increase further as the mean surface temperature increases. Costs here are extremely variable; as some hurricanes can strike empty land and some hit cities, but we're talking a few billion dollars extra each year in insurance claims.
Fourthly, there is the fertility of land and viability for farming. Temperature rises over arid areas like the Southwestern US could cause major farming problems; the exact scale of temperature change is unknown, but some are saying that a local increase of 8 degrees C over the continental US is possible this century; this would probably render most of the Southwestern states economically uninhabitable; in resource terms, the return on investments spent irrigating Arizona, New Mexico and Texas wouldn't be worth it; it would be simpler to just abandon them. If the Midwest agriculture is severely disrupted, it will mean the end of the US as a superpower; certainly a massive price hike on farmed goods is likely.
Fifthly, there is the question of exactly how people will react to these changes; and how they will react; there are at least 3 points of serious conflict over fragile water resources pending; namely India/Pakistan, Israel/Syria/Turkey/Iraq and India/China/Korea; all three of which involve known belligerents in possession of nuclear weapons and intercontinental capability; the UN is predicting war in at least one of these flashpoints within the next 25 years. Massive disenfranchisement and unrest are a possibility, especially in poorer countries.
: If effects x and y are to happen then which actions are appropriate to avoid/ adapt/ take advantage of those changes?
The number of things we can do to avoid these changes is lessening by the day, as the three said. Adapting is what we will have to do, like it or not. I suspect this will involve simply abandoning large areas of land for the moment. As for taking advantage; well, if you make sea walls, arms, insect repellent and the like, you should make a killing.
: The importance of the issue means we must not act in haste, its too important to rush about panicking, over reacting, under reacting or pointlessly criminalising various activities.
The evidence is clear enough for the time to be acting in haste to be past; we need to start acting now; especially as many of the greenhouse gases linger in the atmosphere for the best part of a century.
: What do you think should be done?
I honestly don't know. I would suggest limiting consumption and instituting a more efficient and egalitarian system. What I think will happen, in all honesty, is suffering on an unprecedented scale; I don't like the idea, which is why I try to do what I can to stop it; but I suspect that it's going to happen anyway.
And when people finally come out of their shelters and start rebuilding things, we're going to need to start building a society that can work at the small level; a society that utilizes the talents of the greatest number of people and doesn't require a working national infrastructure.
That's why I think that a positive anarchism is the most promising political system for the future. I think it's rather too late to stop the course now; but we must make sure that it never happens again. The crash will happen; a lot of people will die (including myself); but humanity as whole will survive.