Even those who deny the existence of global climate change are having trouble dismissing the evidence of the last year. In the U.S. alone, nearly 1,000 tornadoes have ripped across the heartland, killing more than 500 people and inflicting $9 billion in damage. The Midwest suffered the wettest April in 116 years, forcing the Mississippi to flood thousands of square miles, even as drought-plagued Texas suffered the driest month in a century. Worldwide, the litany of weather’s extremes has reached biblical proportions. The 2010 heat wave in Russia killed an estimated 15,000 people. Floods in Australia and Pakistan killed 2,000 and left large swaths of each country under water. A months-long drought in China has devastated millions of acres of farmland. And the temperature keeps rising: 2010 was the hottest year on earth since weather records began.

From these and other extreme-weather events, one lesson is sinking in with terrifying certainty. The stable climate of the last 12,000 years is gone. Which means you haven’t seen anything yet. And we are not prepared.

Picture California a few decades from now, a place so hot and arid the state’s trademark orange and lemon trees have been replaced with olive trees that can handle the new climate. Alternating floods and droughts have made it impossible for the reservoirs to capture enough drinking water. The picturesque Highway 1, sections of which are already periodically being washed out by storm surges and mudslides, will have to be rerouted inland, possibly through a mountain. These aren’t scenes from another deadly weather thriller like The Day After Tomorrow. They’re all changes that California officials believe they need to brace for within the next decade or two. And they aren’t alone.