Greens are blue about Black Friday

"In the climate change sense, it's not that every other retail day isn't bad. This just happens to be the worst day for the environment," says Bill Sheehan, executive director of the Product Policy Institute, a nonprofit that aims to prevent waste through better design.

Shoppers will buy mountains of limited-use products wrapped up in disposable boxes, bubble wrap, Styrofoam and other packing materials. It's a lot of trash that's not going to go away - and the production of those products has a major effect.

Consider the average microwave oven: It comes in a cardboard box, wrapped in a plastic bag, sandwiched with at least four chunks of Styrofoam and bubble wrap. A new pair of shoes comes in a cardboard box with tissue paper stuffed around and inside the soles.

A recent U.S. Environmental Protection Agency report found that nonfood products and packaging are associated with 37 percent of America's greenhouse gas emissions - making them the largest source of greenhouse gases. A similar analysis by PPI puts that number closer to 44 percent when the emissions used to produce imported products are included.

"It's the biggest shopping day of the year. It's the day we're celebrating consumption and encouraging people to go buy stuff," said Sheehan. "But we want people to be aware that buying stuff has huge climate change implications. [Obama] has missed the elephant in the room."