It clearly can be a multi trillion dollars project, if implemented. The question is how and what it will impact the world economy, particularly the currecnies. Q "Fix global warming now, or pay later" http://www.theaustralian.news.com.au/story/0,20867,20673944-601,00.html Acting now to cut carbon emissions would cost 1per cent of global GDP a year, about $500billion, he found. By doing nothing, the costs at the time would be a minimum of 5 per cent of GDP a year, and as high as 20 per cent a year. UQ "Stern review final report (pdf)" http://www.hm-treasury.gov.uk/indep...nomics_climate_change/stern_review_report.cfm