One section says: What the debate comes down to is not whether changes are coming but when they’ll occur—and how severe they’ll be. There is serious scientific disagreement about such vital questions as how fast and far temperatures, seas, and storm strength could rise. Warmer waters, for example, could lead to more Katrina-strength hurricanes. Yet new studies find that hurricanes might be torn apart by wind conditions associated with, yes, rising temperatures. This uncertainty is not humanity’s friend, experts say, especially as the global population crests in coming decades, putting ever more people at risk of flooding, famine, and other climate-driven threats.
“We’re altering the environment far faster than we can possibly predict the consequences,” says Stephen H. Schneider, 62, a
Schneider has long believed that responding to the greenhouse challenge is as much about hedging against uncertain risks as it is about dealing with what is clearly known. And the risks, as he sees it, are clear: there is a real chance things could be much worse than the midrange projections of a few degrees of warming in this century—and any thought that more science will magically clarify what lies ahead is probably wishful thinking.
When he lectures about global warming these days, Schneider often asks listeners about a more familiar risk. “How many of you have had a serious fire in your home?” he begins. In a crowd of 300 or so, usually three or four hands rise.
His next question: “How many of you buy fire insurance?”
Hundreds of hands go up.
For Schneider that pattern shows how well people deal with uncertain but potentially calamitous risks in their daily lives. The trick lies in transferring that same behavior to dealing with a risk facing our common home—the planet itself.