Ocean Waves Pounding Harder

April 21, 2008 -- Seismologists have discovered a trove of seismic noise from storm surf that provides a new record of global warming's effects on storms.

The pounding of storm waves on any shore creates vibrations in the Earth that can be heard by seismometers and translated into storm power. The archived seismological data now show that this wave energy has been getting stronger for decades, matching what's predicted to happen as the world's oceans and air heat up.

An analysis of decades of digital seismic data at 22 seismic stations worldwide shows that the power of most powerful storm waves is on the rise in every case.

"As I started to plot them my jaw started to drop," said seismologist Rick Aster of the New Mexico Institute of Mining and Technology. Aster presented the results last week at the annual meeting of the Seismological Society of America in Santa Fe, N.M.

For decades the seismic signals from ocean waves was considered mere noise to seismologists. But then researchers like Aster's colleagues Peter Bromirski and Dan McNamara started mining that noise for information.

"We've got a really remarkable record in the seismological community," said Aster.