Contrary to modern assumptions, the Holocene—the last 10,000 years—was not a time of steady climate. Hubert Lamb identified four major climate epochs: 1️⃣ The Postglacial Optimum 2️⃣ The Iron Age Cold Period 3️⃣ The Medieval Warm Period 4️⃣ The Little Ice Age Even the Arctic Ocean may have been ice-free in summer. The past wasn’t stable. So why assume the present is? | The Randall Carlson