Will Dolphins Need Noise-Canceling Headphones? Rising CO2 Could Lead to Louder Oceans
Researchers at the University of Hawaii have discovered a strange and potentially damaging result of increased CO2 in the atmosphere: louder oceans. More CO2 in the atmosphere leads to more acidic seas and more acidic seas produce fewer sound-absorbing chemical reactions meaning noise will travel farther and be louder.
The researchers have used ocean models and CO2 projections to predict regional sound absorption changes. They found that seas in the upper latitudes and deepwater formations will be most dramatically impacted (these areas are facing the worst acidification) with sound absorption falling by 60 percent.
Low frequency sounds (1,000 - 5,000 hertz) like ship propellers and military sonar will be louder, but scientists aren't sure yet what the impact on marine life will be. The worst-case scenario is that those louder man-made sounds will interfere with marine mammal communication and echolocation sounds. On the other hand, the animal sounds will be louder and travel farther too, so their calls might not be drowned out. The researchers are continuing their studies to find out.
via NY Times