06/18/2012 11:52 am ET Updated Aug 18, 2012

Rio+20: 'I Want to Light a Fire, and Remind You of the Urgency of Our Task'

In less than two days, world leaders will gather in Rio de Janeiro to discuss the fate of our planet whose future now hangs in the balance.

Earlier this month, scientists warned that the world is heading towards a catastrophic tipping point which will usher in changes not seen for some 12,000 years:

"There is a very high possibility that by the end of the century, the Earth is going to be a very different place. You can envision these state changes as a fast period of adjustment where we get pushed through the eye of the needle."

"As we're going through the eye of the needle, that's when we see political and economic strife, war and famine," says Anthony Barnosky from Berkeley University.

If that sounds apocalyptic, it is. And, what's worse, such views are echoed across most of the scientific community. According to a recent report from the United Nations Environment Program: "If humanity does not urgently change its ways, several critical thresholds may be exceeded, beyond which abrupt and generally irreversible changes to the life-support functions of the planet could occur."

A few months ago, the International Energy Agency (IEA) sounded a very loud alarm. It said that the planet could experience a 6 degrees Celsius temperature rise by the end of this century. "Energy-related CO2 emissions are at historic highs, we estimate that energy use and CO2 emissions would almost double by 2050."

A 6C temperature rise will not only be uncomfortable -- it will mark the end of most life here on earth. According to the IEA, we only have five years to act. After that, global warming will hit the point of no return.

This leaves our planet and collective future in a rather precarious state. Yet, in the face of such astounding revelations, world leaders are still reluctant to commit to sustainable development.

Once again, the economic crisis in Europe has taken center stage, whilst delegates continue to squabble over the definition of "green economy" which may take years to refine.

But, as Luiz Figueiredo from the Brazilian delegation points out, "we cannot be held hostage to the financial crises in rich countries. We are here to think about the long term."

How has the largest environmental meeting in history become mired in such deadlock and despair? In the words of Mikhail Gorbachev, former President of the Soviet Union and 1990 Nobel Peace Prize laureate:

"The opportunity to build a safer, fairer and more united world has been largely squandered. I can't qualify this failure as being anything other than one of leadership and vision."

Time has been squandered, but we still have a chance to build a future for our children's children. However, we have to start now, for as the Prince of Wales points out, "once the worst does happen, this time around it will be too late to act."

In the midst of the worst financial crisis since the Great Depression, we need to recognize that our economic and environmental woes are two sides of the same problem -- a wider systematic failure caused by a world that is quite simply "too full".

As Paul Gilding, author of The Great Disruption points out, "we see the occupy protest, spiraling debt crises, rising food and oil prices. And mistakenly, we see these as individual problems. In fact, it is our system that is breaking down."

Last week, the world's leading scientists called for immediate action on population control and over consumption: "We are living beyond the planet's means. We're now at a point in human history where we risk degrading the life support system for human development," says Gisbet Glaser from the International Council for Science.

What the world needs now is a dramatic paradigm shift fronted by brave leadership that is willing to guide us through these turbulent times. In the words Ban Ki-moon, the UN's Secretary General:

"For too long we have tried to consume our way to prosperity. Look at the cost: polluted lands and oceans, climate change, and growing scarcity of resources. We need to invent a new model; a model that offers growth that is more respectful of the planet's finite resources. I want to light a fire, and remind you of the urgency of our task. If we do not take firm action, we may be heading towards the end - the end of our future"

As Gorbachev points out, "in the face of every great challenge there is always a choice. The future is not predetermined. The question is whether we want to ensure a safe and sustainable future for everybody, or keep being held hostage by the current mix of political and economic interests."

So, as world leaders prepare to gather in Rio, let's hope that they make the right choice, for the future that we want lies in their hands. Winston Churchill once said that "success is the ability to go from one failure to another with no loss of enthusiasm .. We make a living by what we get, but a life by what we give."

Although we may have failed in the past, the future that we want still represents a beacon of hope which we must strive towards with courage and determination; for it is here, and only here that we will find the world that we are looking for.