New research suggests that as the world's oceans become more acidic due to global warming, their acoustic properties may change, allowing low-frequency sounds to travel farther than they do today, similar to how they did in the Cretaceous period.
By 2100 low-frequency sounds, specifically those used by whales for communication, near the ocean surface may travel twice as far as they do today.Science Daily sums up the work, published by the Acoustical Society of America:
Using boron's sound absorption traits and impact on low-frequency transmission, [Rhode Island acoustician David] Browning and his colleagues were able to predict the soundscape of ancient oceans to conclude that 300 million years ago, during the Paleozoic, the low frequency sound transmission in the ocean was similar to conditions today. They also found that transmission improved as the ocean became more acidic, reaching its best transmission value around 110 million years ago.
It's all pretty cold comfort considering it may be brought about because of conditions that devastate the oceans otherwise, but nevertheless it's really a pretty cool discovery.