According to a story (A Radical Step to Preserve a Species: Assisted Migration by Carl Zimmer) run in the Science Times section of the New York Times (Tuesday, January 23, 2007) “Climate scientists expect that the planet will become warmer in the next century if humans continue to produce greenhouse gases like carbon dioxide.”
Read that again: “Climate scientists expect that the planet will become warmer … if humans continue to … [breathe]…”
After all, isn’t carbon dioxide the byproduct of human respiration?