GLOBAL freight volumes could quadruple by 2050, according to a study from a group representing 34 affluent nations, the Organisation for Economic Cooperation and Development (OECD).

An OECD unit, the International Transport Forum, said that while the short-term outlook for trade and freight is bleak, "conditions for returning to growth exist".

Faster growth is expected in non-OECD countries. The study anticipates freight growth to be 2.5- to 5.5-times that of less affluent non-OECD countries by 2050, compared to 1.5- to 2.5-times in the richer OECD nations, according to the Transport Outlook 2012 report.

"The impact of the current economic crises could well be a permanent loss of output rather than a direct return to pre-crises growth path. Freight volumes could grow by a factor of four," the report said.

"Governments will have to complete a balancing act between reducing debt while maintaining growth and avoid policy-induced slowdowns. Conditions for growth exist. Pessimism about a prolonged slump need not extend to the longer run," he said.

The study said often freight volumes grow in line with output, but sometimes they are "decoupled" and grow more slowly. But the report also said "for the near- to medium-term and in particular for emerging economies, the high freight growth scenario appears more likely".