Air Date: Week of June 16, 2000

Cynthia Graber reports on new techniques that allow scientists to measure rainfall on the open ocean.

Transcript

GRABER: This is a sound you've probably never heard before -- it's an underwater recording of raindrops falling on the ocean. Until recently, scientists have only been able to measure the amount of rain that falls on land. But, now, they've discovered a way to measure how much rain falls on water. And this is how they do it. When rain falls, it makes two sounds -- a slap as it hits the water's surface, and a ringing tone created by the air bubbles trapped beneath the surface. By analyzing slaps and the ringing recorded by special microphones twenty feet under the waves, scientists are able to decipher just how big the raindrops are and how fast they are falling. These hearing devices are placed throughout the Pacific, where researchers are trying to measure tropical rainfall -- helping them better understand weather patterns and the process of global climate change. And that's this week's technology update. I'm Cynthia Graber.