Politicians must offset damage from man-made pollution, the report says
A team of environmental researchers in the US has warned many effects of climate change are irreversible.
The scientists concluded global temperatures could remain high for 1,000 years, even if carbon emissions can somehow be halted.
The report by the National Oceanic and Atmospheric Administration in Colorado comes as President Obama announces a review of vehicle emission standards.
It appears in the journal Proceedings of the National Academy of Sciences.
The scientists have been researching global warming and the consequences for policymakers.
The team warned that, if carbon levels in the atmosphere continued to rise, there would be less rainfall in already dry areas of southern Europe, North America, parts of Africa and Australia.
The scientists say the oceans are currently slowing down global warming by absorbing heat, but they will eventually release that heat back into the air.
They say politicians must now offset environmental damage already done by man-made pollution.
"People have imagined that if we stopped emitting carbon dioxide the climate would go back to normal in 100 years, 200 year - that's not true," said researcher Susan Solomon, the lead author of the report, quoted by AP news agency.
Their conclusions come as President Obama ordered the US Environmental Protection Agency to review rules on carbon emissions from passenger vehicles.