Unless you're a 20-year-old, trust-fund baby with an underdeveloped prefrontal cortex, you probably think a lot about risk when you manage your investment portfolio. You might be surprised to hear that considering non-traditional factors, such as environmental management, may help to reduce risk in your holdings.

John Vechey of PopCap Games recently joined The Motley Fool for a climate change summit. Among his guests were Stu Dalheim, vice president of shareholder advocacy at Calvert Investments, and Todd Larsen, director of corporate responsibility for Green America.

In the video below, Larsen tells Foolish investors how greening your portfolio can provide comparable or even improved returns, while Dalheim discusses the Carbon Disclosure Project (CDP) as one way that investors are expressing interest in climate issues and how businesses are acting to respond.

Companies certainly seem to think that the CDP is important. Exelon (EXC 0.56%) recently announced that it had significantly surpassed its emission-reduction targets. The company emphasized its inclusion in the S&P 500 Carbon Disclosure Leadership Index, which is administered by CDP. Similarly, in its recent announcement that its second-quarter earnings call would take place on Aug. 6, Spectra Energy (SE) made prominent reference to its inclusion in the CDP's Global 500 and the S&P 500 Carbon Disclosure Leadership Indexes.

In releasing its fifth annual CDP disclosure this month, Union Pacific (UNP -1.82%) discussed its efforts to reduce greenhouse gas emissions by using fuel more efficiently. "Environmental sustainability is a vital consideration in Union Pacific's business planning and practices," explained Bob Grimaila, vice president of safety, security, and environment.

Watch the video below to hear the experts' takes on how solid environmental management can reduce risk exposure.