Delegates listen to a speaker during the annual meeting of the World Economic Forum (WEF) in Davos January 25, 2013.[Photo/Agencies]

DAVOS, Switzerland - Climate change is back on the global agenda, with debate in the corridors at Davos given fresh impetus by US President Barack Obama and UN Secretary-General Ban Ki-moon both highlighting it as top priority this week.

Yet business leaders are still struggling to find the economic incentives to change current practices.

The World Economic Forum (WEF) has not held back in its own assessment of the dangers, with former Mexican president Felipe Calderon warning of "a climate crisis with potentially devastating impacts on the global economy".

Christine Lagarde, managing director of the International Monetary Fund, summed it up for any Davos doubters: "Unless we take action on climate change, future generations will be roasted, toasted, fried and grilled."

There is a disconnect, however, between increasing evidence of extreme weather - from Superstorm Sandy in the United States in October to record heat in Australia this month - and the limited response from politicians and businesses.

In some cases the clash is stark, as highlighted on Friday when Greenpeace activists shut down a Shell gas station near the WEF meeting in protest at oil drilling in the Arctic that is made easier by a warmer world.

Many companies tout the opportunities presented by a shift to a low-carbon economy, yet the reality is that the continuing economic crisis has discouraged businesses and governments from developing a truly long-term view.

The rapid growth in shale gas - a greener alternative to coal when it is burned, although not when it leaks into the atmosphere - has also made renewables comparatively less attractive, adding to the challenge.