The global business community is fast embracing the concept of reporting on its greenhouse gas emissions, according to a major new report from lobby group the Carbon Disclosure Project (CDP).

The fifth annual report found that over three quarters of the FTSE 500 companies that responded to its survey had emission reduction strategies in place, compared to less than half last year.

Furthermore, 80 percent of respondents recognised climate change as presenting both risks and opportunities to their business.

The findings were not universally upbeat with the report also revealing that a fifth of companies had rejected shareholders requests for information on their response to climate change. However, the report concluded that overall "there is a continued growth of awareness about the financial and competitive implications of climate change, among both corporations and investors".

It added that firms were also displaying a more "nuanced appreciation for climate change's specific and differential impacts on particular industry sectors" and had realised there was a need to address both the risks and commercial opportunities offered by climate change.

The findings are likely to be welcomed by IT giant Sun Microsystems, which used the launch event to unveil a new online community designed to help organisations develop and share best practices for calculating, reporting and reducing carbon emissions.

Described by the IT giant as "a Facebook for the Eco-Warrior", the new OpenEco.org site aims to emulate the success Sun has enjoyed through its various community-based, or open source, software development projects by providing a free and open forum for environmentally-conscious business execs to share data and ideas.

Richard Barrington, head of public policy for Sun UK, said the provision of an entirely free and open online community would make it easier for firms to navigate the maze of different approaches to measuring and reducing carbon emissions, many of which have become proprietary and require expensive consultants to implement.

"There is a lot of rubbish out there in the marketplace and a real lack of clarity on how to measure and cut carbon emissions," he said. "We want to publish this best practice data openly and allow firms to more easily benchmark and set realistic targets for emission reductions."

He added that the site, which has been endorsed by the Ceres coalition of investors and green groups, would aim to cover all elements of green business strategies, ultimately providing information on how to measure everything from building energy efficiency to car fleet performance.

Sun said it was confident that firms were willing to work together on their climate change strategies. "There is a competitive advantage to be had in how you position your brand [with regards to the environment]," said Barrington. " But there is not the same proprietary sensitivity around issues of energy use. The only companies that are going to object to initiatives like OpenEco.org are those that aren't doing very well and cutting emissions, the rest are showing a willingness to share best practices."

In related news, the CDP inked an agreement with retail giant Wal-Mart to support the company's attempts to force its supply chain to report on its greenhouse gas emissions and cut emission levels.

"This partnership between CDP and Wal-Mart is a very significant milestone in corporate action to mitigate climate change," said CDP chief executive Paul Dickinson. "By engaging its supply chain in the CDP process, Wal-Mart will encourage its suppliers to measure and manage their greenhouse gas emissions, and ultimately reduce the total carbon footprint of Wal-Mart's indirect emissions. We look forward to other global corporations following Wal-Mart's lead and partnering with CDP."