Silencing the Bomb Page 18

  A CIA press release on November 4, 1997, stated that “a seismic event occurred on August 16, 1997, in the Kara Sea. That seismic event was almost certainly not associated with the activities at Novaya Zemlya and was not nuclear. However, from the seismic data, experts cannot say with certainty whether the Kara Sea event was an explosion or an earthquake.” Nonetheless, many experts in the United States and abroad had concluded weeks before that it was an earthquake. While the CIA press release goes some distance in saying the event was not nuclear, no mention was made publicly that U.S. officials had earlier made a rush to judgment. In my opinion, the experts cited in the 1997 CIA press release should have been fired.

  The early press releases about the seismic event of August 16, 1997, led some conservative commentators and organizations to continue to dig in their heels about its being a nuclear explosion long after a scientific consensus emerged that it was an earthquake. For example, Jeffrey Smith’s article stated, “Frank Gafney, director of the Center for Security Policy, said evidence his group is gathering bolsters the case that the tremor resulted from a nuclear test.” Gafney, much like Richard Perle, frequently opposed various arms control treaties and proposals. Neither he nor Perle is a scientist, but each often has claimed to have inside information.

  The Report on CTBT Technical Issues by the U.S. National Academies in 2012 “drew three lessons from the handling of the 1997 event: (1) use all available data for accurate estimates of location and event characterization, (2) avoid the use of only a narrow range of azimuths such as those to southern Norway and Finland, and (3) provide a mechanism for new information to be updated to policy makers as it becomes available for occasional ‘problem’ events of this type.” Hopefully, these lessons have been learned, as small seismic events on Novaya Zemlya in 2007 and 2009 did not lead to leaks of false assessments to the media. Their high-frequency P to S wave ratios identified them as earthquakes (figure 12.5). Norwegian seismologists located the magnitude 2.8 earthquake of June 26, 2007, within 30 miles (50 km) of the main site where Russia had previously tested.

  A visiting high-level Russian scientist told me later that Boris Yeltsin, president of the Russian Federation, was on vacation when the U.S. press reported the event of 1997 as a likely nuclear test. Yeltsin thought the head of the Russian Ministry of Atomic Energy had deceived him and that the agency had, in fact, conducted a nuclear test. He bawled out the minister over the telephone. Knowledgeable Russian geophysicists quickly conveyed to Yeltsin that the event was a small earthquake in the Kara Sea. My source told me this would have been a much more serious incident between the United States and the USSR if it had happened during the height of the Cold War.

  While press reports about small seismic events on and near Novaya Zemlya largely ceased after 1997, some stories continued to be published in the Washington Times about work at the Russian test site and about Chinese earthquakes being nuclear explosions at or near their Lop Nor test site. Bill Gertz, who had previously leaked incorrect information about Russian seismic events in the 1990s, wrote a story on September 24, 1998, headlined “Blast in Arctic, Satellite Shows.” He wrote, “Vehicle activity photographed recently by a U.S. spy satellite indicates Russia is preparing to set off an underground blast at a remote Arctic nuclear-testing site, The Washington Times has learned.”

  Gertz coauthored a similar story on June 18, 1999, under the headline “Inside the Ring: Small Nuke Test?” which said, “China set off a small nuclear-related blast over the weekend—days before U.S. Undersecretary of State Thomas Pickering arrived in Beijing to deliver the latest American apology, according to Pentagon intelligence sources.” Daryl Kimball of the Arms Control Association emailed me, “My sources tell me that: the report is based on satellite imagery only; that there is no seismic signature for this event from the official U.S. seismic stations (which are capable of detection to very low levels around Lop Nor); and that the AFTAC radionuclide surveillance plane has been sent and has found nothing related to the event.” China may have conducted a subcritical experiment (hydrodynamic test), as the United States and Russia had done already several times since the CTBT was signed in 1996.

  IMPROVED DETECTION AND IDENTIFICATION CAPABILITIES

  Detection and identification improved greatly after the Kara Sea earthquakes near Novaya Zemlya of 1986 and 1997 and especially after the earthquakes in Tibet and Central Asia in the late 1960s. The seismic events in Eurasia that the United States claimed as problems or anomalies in 1972 are shown as a bar at the upper right of figure 12.6. The bar at the upper left of figure 12.6 shows the improved capability in 2009 to monitor seismic events on and near Novaya Zemlya.

  FIGURE 12.6

  Problem seismic events are indicated at the top for various dates. Their yield in kilotons (kt), if they had been nuclear explosions, is shown on the horizontal axis at bottom. The bar indicates detection capability in 2009 for monitoring nuclear explosions at Novaya Zemlya. The lower part of figure, as modified from Kidder (1985), shows the frequency of U.S. underground nuclear explosions in Nevada from 1980 through 1984. TTBT indicates the 150-kiloton limit set by the Threshold Test Ban Treaty.

  In 1985 Ray Kidder published the relative frequency of U.S. underground nuclear explosions in Nevada from 1980 to 1984, shown in the main body of Figure 12.6. He argued that peaks in his diagram near 7 to 20 kilotons and near 150 kilotons indicate tests with yields of high importance to the United States, whereas those with yields less than one kiloton were not. My work indicated the yields of past Soviet tests had a pronounced peak near 20 kilotons. The capability to monitor well-coupled explosions at Novaya Zemlya in 2009 is better than that of Kidder’s smallest, less frequent explosions.

  Conversely, nuclear explosions with seismic magnitudes of 4.5 to 5.5, like those of the so-called anomalous events in the CCD report of 1972, are near the peak of testing in figure 12.6. If they could not have been identified, the ability to monitor nuclear tests of military importance would have been poor in 1972. Even then, however, they were identified as earthquakes in our special study of 1976.

  13

  NEGOTIATING THE COMPREHENSIVE TEST BAN: GLOBAL MONITORING, 1993–2016

  The Comprehensive Nuclear Test Ban Treaty (CTBT) was finally signed in September 1996 by Britain, China, France, Israel, Russia, the United States, and more than a hundred other countries. I paraphrase some of the following material from an extensive description by Ola Dahlman of Sweden and colleagues in 2009 about the negotiations that took place from 1993 to 1996.

  NEGOTIATIONS

  In August 1993, the United Nations’ Committee on Disarmament (CD) issued a mandate to its Ad Hoc Committee on a Nuclear Test Ban to negotiate a comprehensive global ban on nuclear testing. Talks began in February 1994 with the establishment of a Working Group on Verification and another to deal with legal issues, the international organization, and entry into force of the treaty.

  The new Working Group on Verification appointed Friends of the Chair, experts for specific verification issues. British geophysicist Peter Marshall, one Friend of the Chair, played a key role in 1995 and 1996 in formulating the global International Monitoring System (IMS). Peter, who died in 2012, deserves great credit for his long, intelligent, and honest efforts in nuclear verification going back to the late 1950s.

  A close connection was established between the Working Group on Verification and the international Group of Scientific Experts (GSE), made up of government-appointed scientific experts, who had previously established three successive exchanges of scientific and technical information for the better detection and identification of seismic events.

  All of the many countries represented in the 1995 negotiations supported a “zero yield” test ban, one in which no release of nuclear energy was permitted. In October 1995, presidents Clinton and Yeltsin announced that their two countries would work together to obtain a zero-yield treaty. Time was of the essence in the CTBT negotiations because many nonnuclear states were not likely to support an i
ndefinite extension of the Nonproliferation Treaty (NPT) in 1995, when its twenty-five-year term expired, unless a CTBT was concluded in 1996. The original NPT specifically stated that the nuclear weapons states would work to achieve a CTBT. The United States also was anxious to see the NPT extended indefinitely, which happened in 1995. That same year the United States announced it would extend its moratorium on nuclear testing until the entry into force of a Comprehensive Nuclear Test Ban Treaty, provided the treaty was signed by September 30, 1996.

  OPPOSITION TO A CTBT IN THE UNITED STATES

  Republican Senator Jon Kyl of Arizona, an opponent of the CTBT, and Democratic Senator Harry Reid of Nevada introduced an amendment to the 1997 defense authorization bill that would have extended the president’s power to order U.S. nuclear weapons tests beyond September 30, 1996. If passed, the amendment would have defied the treaty.

  This divisive bill fortunately was defeated in June 1996 by a Senate vote of 53 to 45. Many people had thought that a Comprehensive Test Ban Treaty would be in place by then. An Associated Press report of June 26 stated, “Proponents of the amendment said they wanted to ensure the safe and dependable operation of the U.S. nuclear arsenal. Opponents said it could disrupt the Geneva talks [on the CTBT] days away from their conclusion.” Had it passed, the amendment would have faced a certain veto by President Clinton.

  For the presidential election of 1996 that pitted Robert Dole against Bill Clinton, the hawkish Republican platform on the CTBT stated: “To cope with the threat of the proliferation of weapons of mass destruction, the United States will have to deter the threat or use of weapons of mass destruction by rogue states. This in turn will require the continuing maintenance and development of nuclear weapons and their periodic testing. The Clinton Administration’s proposed Comprehensive Test Ban Treaty (CTBT) is inconsistent with American security interests.”

  ACTIONS AT THE UN AND PROBLEMS WITH RATIFICATION OF THE CTBT

  The chair of the UN’s ad hoc CTBT negotiating committee delivered to the committee in May 1996 a draft treaty in which he attempted to capture consensus and bridge differences among the views of various nations. Some delegations refused to accept it as a basis for further negotiations, however, preferring to stay with the previous rolling document that contained many brackets with differing texts submitted by various countries. India, for instance, wanted a statement in the preamble about nuclear disarmament in a set time frame. This and other divisive issues became impediments to a CTBT because the work of the Committee on Disarmament and its Ad Hoc Committee on the CTBT required consensus by all parties for a treaty to go forward. This was and continues to be a great weakness of the UN’s Committee on Disarmament.

  While many countries, including the Russian Federation and the United States, stated in July 1996 that they were prepared to accept the draft treaty, India and Iran were not. Because a complete consensus could not be reached, the final text was presented in August 1996 merely as a report to the Committee on Disarmament. Even though the vast majority of states involved in the negotiations wanted to move forward, the text of the treaty itself was held hostage.

  In an effort to bypass this holdup, Australia, a strong supporter of the treaty, introduced the same text to the UN General Assembly as a draft resolution on September 10, 1996. Decisions in the General Assembly do not require consensus and cannot be vetoed. Bhutan, India, and Libya voted against it, five countries abstained, and 158 voted in favor. Thus, on September 24, 1996, the CTBT was opened for signature. President Clinton signed on behalf of the United States, as did representatives of Britain, China, France, and the Russian Republic.

  In the United States, ratification of a treaty requires the Senate to give a two-thirds affirmative vote, called its “advice and consent.” The U.S. House of Representatives is not involved directly in the ratification process. Following an affirmative vote by the Senate, the president must sign a treaty and submit it to the appropriate international body.

  The treaty required that all forty-four states that possessed either nuclear weapons or reactors ratify the treaty before it could enter into force. As of early 2017, 183 countries had ratified the treaty, including France, the Russian Republic, and the United Kingdom, all three acknowledged nuclear weapons states. Included in the forty-four countries are China, Egypt, India, Iran, Israel, North Korea, Pakistan, and the United States, which have not ratified it as of early 2017. Although the United States and China signed the treaty, they still have not ratified it. India, North Korea, and Pakistan, which became nuclear weapons states after 1996, have neither signed nor ratified it.

  INTERNATIONAL MONITORING

  A separate international body, the Comprehensive Nuclear Test Ban Treaty Organization (CTBTO), was established along with a Technical Secretariat under the 1996 treaty. Formally, they are called provisional until the treaty enters into force. The treaty and its protocol describe terms under which on-site inspections of suspicious events could be proposed and undertaken once it enters into force.

  To monitor compliance, an International Monitoring System (IMS) and an International Data Center (IDC), the most elaborate international verification system ever created, were set up within the CTBTO. A Global Telecommunication System transmits data in real or near real time to an international center in Vienna, Austria, that are available to member states. The major players—the United States, Russia, China, and France—receive large amounts of raw data from the center.

  The International Monitoring System includes technologies that had been established by 1963 for monitoring tests in the atmosphere, oceans, and outer space. This ensured that, in addition to explosions underground, tests in all of these environments were covered after the treaty was signed in September 1996.

  The IMS includes stations for monitoring seismic, hydroacoustic, and infrasound waves as well as measuring radioactive particles and noble gases produced by nuclear explosions. Hydroacoustic waves propagate very efficiently in the oceans; infrasound waves travel through the atmosphere at frequencies lower than those humans can detect. Noble gases are elements on the right-hand side of the periodic table. Because they do not react with other elements, they are difficult to contain, even for underground nuclear explosions, and therefore are easiest to detect.

  A variety of countries now have certified laboratories that measure radionuclide particles and gases. Bomb-produced xenon and argon, two noble gases, can be detected at large distances in minute quantities (several atoms) from nuclear explosions in the atmosphere and from some underground nuclear tests. During the past twenty years, there has been a major advance in detecting minute quantities of those two gases.

  Xenon isotopes were detected from the 2006 and 2013 underground explosions set off by North Korea. Those two events, as well as the 2009 nuclear test, all detonated under one mountain, were recorded by many seismograph stations and located very quickly by the International Monitoring Center in Vienna and the U.S. Geological Survey.

  I add an historical footnote here about the leakage of xenon and other gases from past underground tests and the implications for monitoring the CTBT today. More than twenty years ago, Russia and the United States stated that a number of Soviet underground nuclear explosions at Novaya Zemlya generated noble gases that escaped and crossed international boundaries.

  The United States and Russia interpreted leakage of gases differently under the terms of the 1963 Limited Test Ban Treaty. Nevertheless, the treaty states that both the English and Russian versions are equally valid. The differing interpretations hinge on the English phase “radioactive debris” and the Russian phrase “радиоактивных осадков,” or “radioactive precipitates.”

  U.S. officials claimed that debris referred to both precipitates (fallout) and bomb-produced gases. It accused the Soviets of cheating on the LTBT when gases such as xenon were detected beyond the borders of the USSR. The Soviet Union claimed that the 1963 treaty did not cover noble gases because they were not precipitates. In backing
up their claim, they published information on the leakage of gases from a number of underground nuclear tests at Novaya Zemlya, which they might not have done otherwise.

  In the context of the 1996 CTBT, these findings indicate that preventing the escape of noble gases and avoiding their detection is much more difficult to accomplish than detecting the fallout of radioactive solids. Radioactive gases can be released either through drilling back into the site of an explosion at a later date or by purging the air in tunnels that had been used for a nuclear test. This information is a plus for better detection of clandestine testing, even for explosions conducted underground.

  Another CTBT technology is the detection of infrasound, very low frequency sound waves in the atmosphere generated by above ground nuclear tests. It received new emphasis in 1996 after a long hiatus. William Donn, Frank Press, and Maurice Ewing had pioneered this technology at Lamont in the 1950s. Sensitive instruments developed to detect infrasound recorded many large U.S. and Soviet hydrogen bombs detonated in the atmosphere. Stations in South Korea using this technology recorded the much smaller North Korean tests of 2009, 2013, and 2016, even though they were conducted underground.

  Another method uses hydroacoustic waves, which are propagated in the oceans. They were originally studied and monitored for the detection of submarines during World War II and the Cold War. Similar to sound waves that travel in the atmosphere, hydroacoustic waves propagate much more efficiently in the oceans than seismic waves in the solid Earth. France has been a leader in hydroacoustic and infrasound studies since the CTBT was signed in 1996.