Hurricanes that roared across Earth’s surface long ago left their mark inside stalagmites. This gives us a new way of measuring hurricanes that goes back thousands of years instead of 60 years with meteorological records. It may also add to the data linking global warming to the hurricane patterns of recent years.
The key to reading stalagmites comes from a chemical difference between hurricane raindrops and ordinary raindrops. Hurricanes have tall, cold clouds and very humid air. This means that their raindrops are better at clinging onto oxygen 16 – the lighter isotope of oxygen.
Amy Frappier from Boston College, Massachusetts,…
