Interesting article but I am no sure that option 4 would happen in 5-10 years.

AFAIK climate scientists are forever updating their models to fit the latest data. The problem is that there are so many unknowns, just how much methane will be released from the melting permafrost, how quickly will the Greenland icecap melt etc. And the nature of tipping points is that you get a discontinuity of a trend, making extrapolation very uncertain beyond that tipping point. There are just so many unknowns (at least for a lay person like myself).

With all these uncertain scenarios predicted to take place beyond the 4 and 8 year electoral event horizons it is no surprise that we see so much political inertia, not just here but everywhere in the world. It will indeed take real leadership to take preventitive action. It's is time for a new Noah to put his (or her) hand up.

Or, Scenario 5: None of the above - very likely.

As gusi points out wisely, too many unknowns. Extrapolating with unknown variables can lead to no end of hysterical predictions. On the other hand, someone might just get lucky and get it right, but I think choosing next weeks winning Lotto numbers would be a far easier task. Let's just go for the ride and see what happens along the way.

Frankly, whatever does happen, I doubt that man's puny efforts have caused the situation, nor will they be able to do anything about it. Human's have a far too grandiose opinion of themselves. Earth is a lot bigger than mankind.

The article could have added another couple of scenarios.
SCENARIO 5: The Susan Greenfield/Paul Davies (two of Adelaide's past Thinkers in Residence) Scenario. One in which Homo sapiens takes off to slash-and-burn another planet rather than learn to accomodate to the limits of this one.
An interesting one, coming as it does from two notable physicists; and the demographic expectation of an extra 3 billion people in another 50 years.
With inability to satisfy reasonable needs of the present 6 billion, we had better get the task done by that time.
Rocketing people to another planet at the rate of 50 per second for half a century would do it; Extra flights required to take bulldozers for arranging the foundations of infrastructure enabling migrants to avoid a period of living in caves and eating raw (meat?) in the dark. Does this scenario envisage leaving some behind?
SCENARIO 6(a). The Ronnie Regan or "press-the-button" good-versus-evil Scenario; a variation of "The Lord will Provide". It assumes the world has been so compromised by the baddies that is beyond saving; That the the only proper course is to nuke the planet. While all will be crisped, the goodies will sing "We will gather by the river" (Styx) as they wait for ferryman Charon to carry them joyfully into Heaven.
SCENARIO 6(b). The Lord Will Provide Scenario. This assumes that Homo sapiens is more than just an ephemeral blip on the evolutionary radar screen ("We were meant to be here"). That those who are of the right faith will be looked after; for ever-increasing their numbers, God will reward - even if it is only in the "next world".

Considering the Australian Government's stance in relation to proliferation of potential nuclear problems, and its preference for the ascendancy of disinformation rather than science on environmental matters, some variation of SCENARIO 6 seems to be the target for the powers that be.
The pity of it all is that it is not necessary. Society would have much better prospects from leadership by politicians of honesty, common-sense, and statesmanship - if they existed.

Part One

Regarding the environment it might be said that in this increasing corporatised world us ordinary folk could again be caught up in the old controversy about freedom of choice - which in history as regards Christianity was finally partly solved by one of our most famous Christians as well as one of our greatest Western philosophers, St Thomas Aquinas.

It was Aquinas who accepted precepts of Ancient Greek philosophy introduced to the West by Islamic students. Apparently Aquinas had already decided that Christianity had to be lifted out of the doleful period we now know as the Dark Ages. Thus it came about that Christian faith became tempered with Aristotelian Reason, which not only greatly influenced the Rennaissance with thoughts more of earthly progress besides an afterlife, but which also gave great impetus to science and the Age of Reason followed by the the Age of Enlightenment-then into the exciting but problematic Democratic Age we are living in now - sensible reason, according to sociologists having become replaced once again with the crude animalistic doctrine of the survival of the fittest.

It was Darwin himself who died condemning former compatriots like Herbert Spencer and Walter Bagehot for helping to form what we now know as Darwinian Socialism, which not only gave more impetus to an already rampant colonialism later proven by the British invasion of South Africa and American imperial adventures into the Spanish possessions on both sides of the Pacific, as well as capturing Hawai.

Further, it was the so-called Darwinistic survival of the fittest concept which historians say not only helped begin WW1, but after Versaille, the angry revival of the Germanic Wermacht, giving sanction to Hitler to give command for all the horrendous Nazi Germanic atrocities WW2.

How impressive it was for America and her victorious allies to forgive the German people for following the fanatical Hitler, gifting them with the Marshall Plan, along with Japan. Also ridding the world of Soviet Stalinism placing the US by then in the global academy award status

Scenario 7 – Pandemic. Not to the extent that it wipes out our species, but to the extent of relieving the world of the massive human population pressure, thus allowing us to basically practice business as usual, but at a much-reduced scale…. until populations build up again, by which time we will have at least a little bit more wisdom and will to live sustainably….. maybe. Or maybe we will have to go through several cycles until we collectively get it through our thick heads.

Scenario 8 - Peak oil. As fuel prices rise, the price of just about everything else rises as well. The economics for families and for all sorts of businesses no longer work. Food and basic commodities are unaffordable, or unavailable due to broken supply lines and terminated production lines. Unemployment becomes rife. Alternative fuel sources just completely fail to match either quantity of affordability of petroleum. Oil wars are beefed right up. Australia’s share of imported oil is stolen by the US. Civil strife ensues and all the world’s countries that are dependent on fossil fuels fall apart. Most of the rest of the world also suffers greatly due to halted food imports and other connecting factors.

I think both of these scenarios are more likely than any of the previously mentioned ones.

One thing to remember is how fragile our specialised society is. Most people study or do aprentiships till they are at least 20 years old. Many study much longer. If for some reason that is not possible because youngsters are required to grow food or fight others much knowledge and skills could be lost and we'd end up in a new dark ages.

@Ludwig the Marshall plan wasn't all altruism. Europe was in ruins, food was rationed for years after the war and the soviet union had been very succesful in its industrialisation in the 30's. France and Italy had huge communist parties and Germany could have gone that way too. One of the conditions of the Marshall plan was that communist parties would be banned and the participants set up liberal democracies. While this choice seems like a no brainer today we shouldn't forget that after WWI many democracries had been setup that soon collapsed and by the 30s had been replaced by dictatorships. Immedeately after WWII communism seemed very attractive to many Europeans and the Marshall plan was devised to counter it. We could in fact argue that the EU is an extention of the Marshall plan as new members get vast amounts of aid and have to commit to a western style democarcy. It is a pity the US couldn't have done the same in their own backyard (Caribian and Central America) I am sure the place would be much more democratic and wealthy. Anyway I digress...

Sorry, @ludwig should be @bushbred.

Bushbred Part Two

Unfortunately, corporate greed and hegemon has now trapped the US like a huge fester, as it has trapped Britain, as well as Australia, and has really trapped us in Iraq. Like the blind leading the blind, our leaders have been too blind to see that corporatism is really nothing new, as proven by the East India Company which finally gained control of the whole of Ceylon.

Simply the economies of scale, as Adam Smith knew all about, play along carefully and you will have the lot. But it was Adam Smith who warned to remember you are dealing with people, who as a social philosopher thought also about the proletariat as part of his Wealth of Nations.

Maybe Bill Gates is another one who thinks about people, though some say he will get back more than he gives away - though he at least gives indication how with corporatism most of the wealth will rise to the top like junket does to milk.

But after thousands of years, as Darwin made clear before he died. For humans, we surely should have found a kinder and more compassionate way to make money and live our lives different to the animals.

The point is, even through the ballot box, with economic rationalism and corporate power mesmerising both sides of government, we lower ranks have now lost the license to make the choice

This is only part of one picture.

There are many other problems from toxins and CO2 emissions endemic on this planet that will effect the human race.

For example, toxins in air and water is already effecting men's sperm counts. Currently this doesn't appear to pose much threat: only some men are affected at the moment.

More men will become more sterile as the toxins lower their sperm counts. Few will have access to technology to remedy this problem.

With cancers caused by no ozone layered sun, toxic radiation, and other pollutions in the air, the human immune systems will seriously be lowered by such toxins and environments.

The outcome will be more people will have similar symptoms as those who have AIDS. Not caused by a virus, but caused by constant environmental attack on our bodies. This will raise our death toll. People will be dependant on the pills, therefore depend on corporations that own these patents. Diseases and parasites will thrive as they do on sick bodies. Old viruses will return and mutate with vengeance, especially with global warming.

The human population will need to be modified genetically in order to copulate and survive. Yet these GM modifications will be patented by the corporations. Our grandchildren's bodies could end up being owned by the corporations that designed their survival and their pills.

Since 2002, according to the US Supreme Court, any corporation can patent any life form, and expect limitless royalties, especially from GM seeds and body parts used in medicine. This was a huge milestone in the history of life on Earth. This is why US farmers see GM products as a virus. Seed infection spread by wind and birds means that corporations can take over any farm by royalties internationally once they prove that their seed in on your property.

As the CO2 crisis could subside with population decline, another monster could be facing us behind this smoke screen.

No one knows what the future will hold. The possibilities are infinite with so many variables but they do not just boil down to 4 scenarios.

Ludwig,
An extension of your Scenario 8:
The impact of peak oil, or no oil, will hurt both oil consumers & oil producers.(& some other posters on other topics have already alluded to it)

But while oil consumers may well develop suitable alternatives to oil.It is less likely the oil producers are going to find an equally lucrative alternative.

So then, how do the oil producers continue to support their burgeoning populations & extravagant infrastructures when the intravenous drip from oil revenue is removed?
Internal civil strife, more export terrorism, and mass migration to other parts of the world -and guess what places will be their countries of first choice.

An individuals most favored scenario will depend on ones general attitude and demeanor, optimistic or pessimistic.

Recalling the competing demands for fuel to heat the furnaces of the first industrial revolution which, in competition to wood for ships saw the development of coking coal.

That was followed by the Victorian pessimists who could not see the development of deeper coal mines, oil exploration or nuclear energy and thought the worlds energy resources would be depleted by 1850.

It is always easier for individuals to anticipate the inability of the world to invent solutions or to change circumstances than to anticipate unseen and unknown solutions - thus, the general view of the future will always tend toward the pessimistic.

The danger of this when the alarmist hysteria when a bunch of so called "experts" is applied and they put their collective ignorance together in pursuit of research funds, ignoring the natural energy and the capacity of other individuals to produce revolutionary solutions to everyday problems.

Based on the real experience of history, the likely outcome is going to be more optimistic than pessimistic.

The idea of “business as usual” is, in fact, just a tepid guess at acknowledging the “don’t know” view.

Thus, a more likely and more realistic outcome scenario is “business is booming”, provided we can fix the world population explosion. Fix that and global warming will disappear, poverty will disappear and overall “life quality” will improve out of site to what it is today.

Col Rouge is absolutely right about the benefits that could come from fixing overpopulation. However, just because technology has saved us in the past doesn't mean that it can in the future. In the 1960s Paul Ehrlich, the Paddock brothers, and other writers were predicting massive famines for the 1970s. In the 1960s India was importing vast amounts of food and had large numbers of malnourished people, as well as a population that was doubling every generation. I doubt if any of the people who sneer at Ehrlich now would have bet serious money on India NOT having a famine. Thanks to the Green Revolution food production is double what it was then, albeit requiring three times more water.

Now, though, we aren't just up against one limiting factor, but a host of different problems. In many cases the obvious solution to problem A makes problem B worse. We can deal with Peak Oil by burning more coal, but that will dump even more carbon dioxide into the atmosphere. More dams may solve an immediate urban water shortage, but also flood good agricultural land, threaten an endangered lungfish, and so on. There is no guarantee that human ingenuity will always save the day. Just think of the Easter Islanders, Greenland Vikings, Sumerian city states, Mayan kingdoms, etc.

Divergence “technology has saved us in the past doesn't mean that it can in the future.”

Maybe not specifically ‘technology’ but human ingenuity, endeavour, competitiveness (which is what stimulates the quest for technology and all other “developments”) will.

Simply, that we do not know what it might be now, in no way diminishes either the likelihood or possibility of a solution to any given problem.

What does matter is the viability of economic return to any development (reward for successful effort).

On that very matter, take oil as an example. The development, in the past 10 years of hybrid engines in cars is a direct response to the need for greater oil conservation. Such developments were neither “cost effective” or “commercially viable” when oil was $5 / barrel. But when oil was seen as increasing toward todays $75 / barrel, they are.

Hence, the monolithic institutions of nationalised industry, which were popular in the early to mid 20th century, did nothing for innovation or development because the governments which controlled them and unions who supported them were hellbent on maintaining the “status quo”.

A cosy unchanging environment is a myth.

The only certainty is “change” and all developments, technological or social or otherwise are some of the physical manifestations of “change”.

So I disagree with your assertion, “Human ingenuity” will “always save the day” because there are no alternatives, absence of “human ingenuity” will do and save nothing.

Have a read of this link concerning the reliability of expert predictions.

http://www.project-syndicate.org/commentary/tetlock1

It's not hard to see how predictions of complex future outcomes go wrong. With so many hundreds of factors that can each cause a radical departure from an expected course, complex predictions simply become stabs in the dark.

And what is apparent in all predictions, is that the farther in time the predicted outcome, the more numerous the intervening events that give rise to exponential possible courses and much less certainty for any specific outcome. In other words, you've got more chance of correctly predicting the weather tomorrow than for next week. So for correctly predicting outcomes, simplicity is key.

But politics is never simple because human behaviour is not simple. Therefore, political predictions are like weather forecasting - you can predict a cool overcast Autumn day for next year, but not 18'C 53% humidity with a light S'West breeze. Who predicted that John Howard would become PM and for so many years? And that Australia would not sign the Kyoto Protocol? So much for the experts.

However, some complex scenarios do merit ongoing analyses and prognoses in order to avert possible catastrophe.

Without the doomsday scenarios of Peak Oil and Global Climate Change, and the resultant public anxiety that influences the political process, how would the ruling powers become motivated to implement the necessary changes to avoid the predicted inevitability?