The Stern Review on the Economics of Climate Change released at the end of October, 2006 sited strong indications that global GDP could fall in the future if enactment to curb climate change is not pursued.  Simply put, “…the benefits of strong and early action far outweigh the economic costs of not acting…” — Executive Summary (short).  If prompt action is required, one can realize that within the landscape of economics, lag-times provide hurdles to any form of regional, national or international frameworks to combat climate change.  A current example can be seen in Canada where the Conservative government has shifted their strategy in reducing greenhouse gas emissions.  The government has indicated that it will take at least a year of consultation with various public and private sector entities to draft any formal and legal binding regulations on the emissions of greenhouse gases.  

Here is a link to the Stern Review:

http://www.hm-treasury.gov.uk/independent_reviews/stern_review_economics_climate_change/stern_review_report.cfm