The growth in greenhouse gas emissions can be curbed at reasonable cost, experts at a major UN climate change conference in Bangkok have agreed. Boosting renewable energy, reducing deforestation and improving energy efficiency can all help, they said. This is the third report this year from the Intergovernmental Panel on Climate Change (IPCC), and aims to set out the costs and benefits of various policies. IPCC chair Rajendra Pachauri said the report was "stunning". "Human society as a whole has to look for changes in consumption patterns," he told reporters at a news conference in the Thai capital. The report suggests that if major climate impacts are to be avoided, global emissions should peak and begin declining within one or two decades. The IPCC has already this year produced the two other elements of this global assessment report - its fourth since 1990 - dealing respectively with the science of climate change and the potential impacts.