From Nuclear Detectors to Whale Discovery: The Unexpected Scientific Utility of a Global Sensor Network

From Nuclear Detectors to Whale Discovery: The Unexpected Scientific Utility of a Global Sensor Network

A Genesis in Nuclear Testing

The development of nuclear weapons during the 1940s unleashed an era marked by fear and instability. Nations raced to build their own arsenals, leading to an arms race that lasted for decades. As the 1990s rolled around, it became clear that transparency was necessary to avoid further nuclear escalation. This realization led to the signing and ratification of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) by several countries, including the United Kingdom and many Western European powers.

While some countries, including China, India, and the United States, did not sign the treaty, the CTBT nevertheless established a global norm against testing. More importantly, it led to the creation of a network capable of detecting nuclear detonations anywhere on Earth.

The International Monitoring System

The International Monitoring System (IMS), run by the CTBT Organization in Vienna, Austria, has been operational since the 1990s. It comprises over 300 installations worldwide, capable of detecting sound, shockwaves, and radioactive materials from nuclear explosions. The system includes more than 120 seismic stations, 11 hydroacoustic microphones in the oceans, 60 infrasound stations, and 80 detectors for radioactive particles or gases.

Many of these installations are located in quiet, relatively undisturbed locations such as the isolated Wake Island in the Pacific or the icy expanses of Antarctica. These remote locations are ideal for picking up the subtle signals that could indicate a nuclear detonation.

Unforeseen Scientific Uses

Over time, the data collected by this vast network has proven useful for more than just nuclear detection. Researchers have used the data to detect otherwise unnoticed events, such as whale songs, shipping noise, submarine volcanic activity, auroras, and glacial landslides.

One notable example includes the first detection of blue whale songs near the Diego Garcia atoll in the Chagos archipelago. The network has also detected significant non-nuclear explosions, such as the Beirut port explosion in 2020 and the Hunga Tonga Hunga Ha’apai volcanic eruption in January 2022.

The Discovery of Pygmy Blue Whales

In 2021, this network led to a significant discovery: a group of pygmy blue whales in the Indian Ocean. Despite their immense size, these whales had managed to evade detection for decades. By analyzing nearly two decades’ worth of acoustic data from the IMS, researchers identified a unique song pattern, leading to the identification of this new population of whales.

This discovery underscores the unexpected scientific breakthroughs that can come from infrastructure initially developed for security purposes. In this instance, a network initially set up to monitor nuclear tests has proven to be a valuable tool for marine biology and earth science. It also highlights the potential for future discoveries and advancements in our understanding of the natural world.

Looking Forward

The potential applications of the data collected by this global network extend far beyond nuclear detection or even marine biology. The rich, diverse data sets can be used to study climate change, monitor natural disasters, and track wildlife, among other things. As our technological capabilities continue to advance, who knows what else we might discover?