AMD next week is set to release its annual Global Climate Protection Plan, its eighth to date. The environmental report is remarkable in its candor, according to those who've read advanced copies. In particular, its disclosure -- best guesses, really -- of how big its carbon footprint is when the entire product supply chain is considered. It's a task that relatively few manufacturers bother to take.That reluctance is understandable, but AMD's courage is commendable.

AMD uses the Greenhouse Gas Protocol to calculate its carbon footprint. Created by the World Resources Institute and the World Business Council for Sustainable Development, it's a widely used accounting tool used by government and business leaders to quantify greenhouse gas emissions.

Among its components is something called Scope 3, a tool used to calculate indirect emissions associated with supply chain, product distribution, employee business travel, and commuting. It's fraught with problems: How can you be sure your suppliers aren't just telling you what you want to hear? Is anyone auditing their claims? How about your suppliers' suppliers -- how green are they? Right now, the answers generally are: you can't, no, and who knows?

Why is Scope 3 important, then? Because it's a start. It puts suppliers on notice that they may soon be held environmentally accountable. "It's true that you don't have control over the suppliers' number," concedes Larry Vertal, senior strategist for AMD Green, the chipmaker's environmental program. "We try and push the envelop in the report to show leadership, but with complete transparency of where we're making estimates. That way we set an example by highlighting where the weaknesses are."

The report will be released on Oct. 29.