Johannesburg — THE world has just five years to move to a low-carbon economy if runaway climate change is to be prevented , says the Climate Solutions II report released by the World Wide Fund for Nature (WWF) last week.

It finds that runaway climate change is almost inevitable without specific action to implement low- carbon reindustrialisation over the next five years.

According to the report, this could be achieved at an estimated cost of between 7-trillion and 17- trillion in short-term investment.

This investment would pay off as a low-carbon economy would be cheaper to operate, the authors of the report say. The point of no return is estimated to be 2014.

"The window to avoiding runaway climate change is still open for a few years, but after this, the possibility of climate change becomes inevitable," the report's chief author, Karl Mallon, said in a conference call from Switzerland on Friday.

Mallon said "very decisive policy interventions" were required to achieve this, but that it would take time to draw up policy, have it approved by governments and signed into law.

The report considers two scenarios: one where carbon emission cuts of 63% relative to 1990 levels occur by 2050, and another where emission cuts equal to 80% on 1990 levels occur, also by 2050.

Under both scenarios, every key low-carbon resource and industry will have to operate at their maximum rate of development by 2014, the authors say.

Such clean industries would need to grow at least 22% a year in order for a 63% reduction scenario to be achieved, and at least 24% a year for the 80% reduction scenario to be achieved.

This scenario creates a significantly better chance of avoiding warming of a global average of 2°C. Going beyond this level means runaway climate change is likely.

In addition, emissions abatements from the forestry and energy sectors must be at the upper end of what is technically possible, the report says.

The resulting economies of scale from these low-carbon revolutions will create major long-term savings and returns when compared to the business-as-usual trajectory, especially in the energy sectors, according to the report.

Clean energy generation, energy efficiency, low-carbon agriculture and sustainable forestry needed to lead this transformation, said the consultancy Climate Risk, which was commissioned to do the report .

The WWF's director of energy policy, Stephan Singer, said a comprehensive, legally binding, ambitious protocol needed to be agreed on at the United Nations Copenhagen climate change conference in December.

But whatever the outcome of negotiations in Copenhagen, work needed to start immediately on developing a low-carbon economy, Singer said.