Foreign Policy Blogs

The CTBTO IMS: More Bang for the Buck (Pun Intended)

In two previous posts, I wrote about the work of three Ohio State University researchers who are using GPS to detect covert nuclear tests.  Now, there is word that the  International Monitoring System (IMS) of the the Comprehensive Test Ban Treaty Organization (CTBTO) is of increasing utility, not only for monitoring nuclear testing, but also environmental monitoring applications.  It seems that the IMS has become a wise investment indeed.

While the U.S. continues to remain outside the CTBT fold, having not ratified the nearly 17 year old pact, the CTBTO and the IMS have been quite busy proving their chops.  Not only did the IMS, now 274 sites strong, quickly discern that the big boom coming from the direction of North Korea on February 12th was actually an underground nuclear test, but three days later, the network of sites “picked up the infrasonic waves coming from the space rock that exploded above Siberia.”

Network of International Monitoring Stations of the CTBTO

Quoting a CTBTO press release, Chris Schneidmiller writes in the Global Security Newswire that “On Feb. 12, as many as 25 CTBT seismic monitoring sites across the globe initially identified ‘seismic event with explosion-like characteristics’ just before 3 a.m. Greenwich Mean Time.  Information was provided to treaty member nations slightly more than an hour later, ahead of Pyongyang’s official declaration.”

He continues: “Technical staff determined the event site to be consistent with the location of Pyongyang’s prior nuclear tests, with a margin of error of roughly 10 miles, and cited the resulting earthquake as registering 5.0 on the Richter scale. Those figures by the end of the week were refined to a 4.9 magnitude and a location certainty with a margin of error of about 5 miles.”  In all, 94 sites picked up the North Korean blast.

Three days later, the IMS sites were again atwitter, this time recording the meteor that exploded on February 15 over Chelyabinsk, Russia.  When it detonated, the blast was detected by 17 infrasound stations in the CTBTO’s network; the furthest station to record the otherwise sub-audible sound was nearly 9,320 miles away in Antarctica.

As if detecting and confirming the Punggye-ri test and recording the meteor explosion weren’t enough, authors Raymond Jeanloz, Inez Fung, Theodore Bowyer and Steven Wofsy recently discussed additional, non-arms control monitoring applications for the extensive IMS. Writing in Science, they describe how the IMS is now being used for environmental monitoring.  They point to the case of the tragic December 2004 Indian Ocean tsunami disaster, in which use of the IMS could have been used to provide advanced warning and saved lives.  As a result, the international array of sensors initially deployed to monitor nuclear explosions is now also being used to enhance tsunami warning in the Indian Ocean.  The CTBTO has also since agreed to other non-treaty applications for the IMS, enhancing its utility and strengthening technical capabilities around the world. According to Jeanloz, Fung, Bowyer and Wofsy, the expertise developed around the IMS and its data have enabled experts to help their respective countries to mitigate or avoid natural catastrophes, pollution, and stresses associated with resource depletion.

“More recently, the ability to monitor radionuclides in the atmosphere—including with IMS measurement systems—played a prominent role in tracking the radioactive plume of gas and debris from the 2011 Fukushima accident. The data provided national health authorities vital information regarding expected dose rates to populations. Atmospheric monitoring has also been key to managing air travel and maintaining safety during volcanic eruptions, aiding hundreds of thousands of individuals.”

Despite these positive developments, some CTBT naysayers continue to question the efficacy of the treaty regime.  For example, some charge that the absence of findings of radioactive particles or chemical elements such as xenon from the North’s test “leaves unanswered a key question of whether plutonium was used again or if the regime for the first time set off a device fueled by highly enriched uranium.”  Critics also charge that countries that want to test nuclear weapons without detection could set off an extremely low-yield detonation or use strategies such as decoupling, which is detonating the device in a large, underground chamber.

No treaty regime is leak-proof or infallible.  But, to use a phrase often thrown around by the inside the Beltway crowd, one should not allow the perfect to be the enemy of the good.  While it is unclear if the CTBTO will be able to address the latest concerns expressed by skeptics, the IMS and its infrastructure have come a very long way since the treaty was rejected by the Senate in 1999.

So, while the U.S., China, Egypt, India, Iran, Israel, North Korea and Pakistan remain outside the treaty, the CTBTO is busy honing its skills in arms control monitoring and beyond.



Jodi Lieberman
Jodi Lieberman

Jodi Lieberman is a veteran of the arms control, nonproliferation, nuclear terrorism and nuclear safety trenches, having worked at the Departments of State, Energy and Nuclear Regulatory Commission. She has also served in an advisory capacity and as professional staff for several members of Congress in both the House and Senate as well as the Senate Homeland Security Committee. Jodi currently spends her time advocating for science issues and funding as the Senior Government Affairs Specialist at the American Physical Society. The views expressed in her posts are her views based on her professional experience but in way should be construed to represent those of her employer.

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