Over the past few years, greenhouse gas emissions disclosure has become routine for most major corporations, even those in the United States; and voluntary emissions reduction goals, too, are becoming widespread. But how significant are these developments, and what are the next steps for concerned citizens?

On Monday, the Carbon Disclosure Project, a coalition of 315 institutional investors, released the results of its fifth annual survey of corporations worldwide. This year 77% of the world's largest 500 companies (FT500) completed the survey and provided emissions data, up from 44% in 2003, its first year.

U.S. companies continue to trail the pack by a significant margin, but for the first time this year, a majority of the S&P500 responded (56%), which the CDP says suggests "that American industry has reached a tipping point in addressing this important issue." Non-responding companies include Apple Computers, Costco, Harley-Davidson, and Safeway.

One notable change this year is the increase in companies reporting an emissions reduction initiative with specific targets and timelines -- 76% of FT500 respondents, up from 48% a year ago. Again, U.S. companies lag significantly, with only 29% of respondents reporting such programs (up from 26% in 2006).

How much progress does this actually represent? The reduction plans are self-reported and unverified, and their goals vary widely, especially in the U.S. While DuPont reports that emissions decreased by 56% between 1990 and 2003, and Intel aims to reduce emissions by 30% per unit of production between 2004 and 2010, companies like Chevron simply aim to keep 2007 emissions below 2006 levels. And the report notes that "American automobile manufacturers continue to focus on reducing their facility (Scope 1) emissions, while not directly addressing GHG emissions from their products (which are a far greater source of emissions)."

The CDP also released a list of 68 leaders in emissions disclosure and reduction, including DaimlerChrysler, Exelon, BP, and Pfizer in high-carbon sectors, as well as Hewlett-Packard, Citigroup, Microsoft, Marks & Spencer, and Wal-Mart in low-carbon sectors. CDP and Wal-Mart announced a partnership to work with Wal-Mart's supply chain on emissions disclosure and reduction.

While CDP is proud of the impact of its work, it also acknowledges its limitations:

Although the CDP5 finds that the gap between awareness and action is shrinking among responding FT500 companies, there is still a huge disconnect between awareness and action on the investor side, the report concluded. The CDP calls on governments to help push investors into using carbon disclosure information in their investment making decisions.

The FT500 Report noted, "The objective of the CDP since its inception has been to increase awareness and provide investor-relevant information about climate change to enable informed action. Unless and until governments agree on material taxation or regulation of greenhouse gas emissions, investors will lack incentive to act, both more systematically and in greater numbers, and the full potential of the project is unlikely to be realized." - Socialfunds.com

What are the next steps for reducing corporate emissions? Along with pushing for government action, should we be taking a stronger stance as consumers and investors to hold companies accountable for disclosing their emissions and making serious efforts to reduce them? Or are such voluntary movements a distraction from working to create, improve, and enforce binding regulatory systems?