Whales and Our Civilisation

Whales and Our Civilisation

Radio frequency pollution

For tens of millions of years, whales, these enormous, intelligent, communicative creatures evolved with essentially no natural enemies. Then the development of the steamship in the 19th century introduced an ominous source of noise pollution. As commercial and military vessels became more abundant, the noise background in the oceans, especially at a frequency of twenty Hertz, became noticeable.

Whales communicating across the oceans must have experienced increasingly greater difficulties. The distance over which they could communicate must have decreased steadily. Two hundred years ago, a typical distance across which finbacks could communicate was perhaps 10,000 kilometers. Today, the corresponding number is perhaps a few hundred kilometers. Do whales know each other’s names? Can they recognize each other as individuals by sound alone? We have cut the whales off from themselves. Creatures that communicated for tens of millions of years have now effectively been silenced.

I wonder, can we control our radio-frequency pollution and listen? Possibly not (Quotations from Megan Jorgensen). Image: © M. Jorgensen (Elena)

There is a curious counterpoint to this story. The preferred radio channel for interstellar communication with other technical civilisations is near a frequency of 1.42 billion Hertz, marked by a radio spectral line of hydrogen, the most abundant atom in the Universe.

We are just beginning to listen here for signal of intelligent origin. But the frequency band is being increasingly encroached upon by civilian and military communications traffic on Earth, and not only by the major powers. We are jamming the interstellar channel. Uncontrolled growth of terrestrial radio technology may prevent us from ready communication with intelligent beings on distant words. Their song may go unanswered because we have not the will to control our radio-frequency pollution and listen.