How can Cornell reduce its greenhouse gas emissions? Some of the best answers to that question may emerge Oct. 22, Campus Sustainability Day, slated for 10 a.m. to 3:30 p.m. in Weill Hall.

Its main event is the Climate Action Plan Idea Exchange -- 10 a.m. to 2 p.m. in the atrium of Weill Hall -- where campus leaders and visitors can talk about ways to reduce the university's carbon footprint. These ideas may become part of the Cornell Climate Action Plan, due out in 2009. The plan will provide a road map for reducing Cornell's greenhouse gas emissions to zero by reducing some emissions and offsetting others. Anyone can add ideas and read about others' ideas at http://www.sustainablecampus.cornell.edu.

A national discussion via a live interactive webcast, "Climate Realities, Challenges and Progress in Higher Education," from 2 to 3:30 p.m., will be shown in 226 Weill Hall. New York Times science reporter Andrew Revkin will moderate a discussion with national experts about the latest scientific information on climate changes and what other schools are doing to reduce greenhouse gasses. Cornell audience members can submit questions during the live program.

Other activities include free samples of locally grown food, a tour of Weill Hall -- which received "gold" certification by the Leadership in Energy and Environmental Design Green Building Rating System -- and a display of a 100-mpg car being developed at Cornell. Student groups will offer information on Ho Plaza to encourage more involvement, and Ithaca Carshare will display one of its cars that are available to everyone in the Cornell and Ithaca communities.

"To achieve climate neutrality, we've got to go way beyond central planning," says Dan Roth, sustainability coordinator in the Office of Environmental Compliance and Sustainability. "It's about partnerships and culture change across campus."

For information on the Cornell Climate Action Plan, see http://www.sustainablecampus.cornell.edu/cap/climateactionplan.cfm.