As evidence mounts that climate change can present significant risk to companies' operations, many individual investors feel powerless to affect corporate management regarding such issues. You might be surprised that you have more pull than you think, and that your voice may matter now more than ever.

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, Dalheim and Larsen talk about one tool that you have in your toolbox: your proxy ballot.

They discuss shareholder resolutions at two specific companies: Southern (SO 1.10%) and ExxonMobil (XOM -0.09%). The shareholder resolution on Southern's ballot in 2012 sought to compel the company to report on its efforts to reduce environmental and health hazards associated with coal combustion waste, garnering 26% support from shareholders. Proponents dropped a 2013 resolution requiring that Southern adopt greenhouse gas emission reduction targets after they received "commitments" from the company.

At ExxonMobil, a shareholder resolution that the company adopt greenhouse gas emission reduction targets has appeared on the proxy ballot for the last three years, each time receiving support from more than a quarter of proxy voters.

The message in the video below? Vote your proxy to influence management.