Climate change will seriously threaten regional human security and national economies this century, according to a report by the Australian government's Commonwealth Scientific and Research Organisation (CSIRO).

"Chronic food and water insecurity and epidemic disease may impede economic development in some nations," the report says.

"Degraded landscapes and inundation of populated areas by rising seas may ultimately displace millions of individuals, forcing intra- and inter-state migration."

The report, commissioned by a coalition of environmental, aid, church and development groups, analyses predictions of temperature increases of up to two degrees Celsius by 2030 and up to seven degrees by 2070.

Scientists blame global warming on greenhouse gases such as carbon dioxide, produced mainly by the burning of fossil fuels including coal and oil, for causing rising temperatures worldwide.

"Rapid growth in large regional economies such as China and India has elevated human prosperity," the report says.

"However, unless ultimately decoupled from fossil-fuel use, such growth also threatens to exacerbate the climate challenge."

The CSIRO says that remaining below the generally accepted threshold for "dangerous" climate change of about two degrees Celsius would require global greenhouse gas emissions to be reduced by 30-55 percent below 1990 levels.

The aid groups that commissioned the report said it was a wake-up call for Australia, one of the world's worst polluters on a per-capita basis.

"Climate change will fundamentally change the way we aid the world's poor," said World Vision Australia chief executive Tim Costello.

"It will undermine the value and impact of current aid spending and will lead to far greater calls for assistance from those hurt most."

Environmental and rights activists also called on the government to prepare to accept environmental refugees fleeing small Pacific island states hit by rising sea levels.

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