Stratospheric circulation and the 1950s nuclear test controversy Dr. Graham Mann (Lecturer in Atmospheric Science, Univ. Leeds) In this Frontiers lecture I seek to explain the historical progression in understanding (research frontier) re: the transport and deposition of global fallout from nuclear tests in the Pacific (not health effects) I will cite heavily from the autobiographical book “An Environmental Odyssey” by Merril Eisenbud who provides fascinating AEC insider accounts from his perspective as Director of the Health and Safety Laboratory (HASL) during the height of the cold war period and the first thermonuclear tests in 1952, 1954 Merril Eisenbud and John Harley (US Atomic Energy Commission Health and Safety Laboratory). Eisenbud & Marley (Science, 1953) Frontier in Environmental Science Research. Chose this topic as example of period when step-change in understanding Some periods in history when the progression in understanding is particularly fast. The 1950s was a unique period in the history of the atmosphere in that the stratosphere had highly elevated concentrations of radionuclides released primarily from the US and UK thermonuclear detonations in the Pacific tests (65 years since Castle Bravo incident). US and UK thermonuclear tests in the tropics polluted the global stratosphere, whereas Soviet tests were mostly at mid to higher latitude. But this talk will focus on the Research Frontier re: global transport of the debris from the very high-yield thermonuclear tests in the Pacific, and how predictions of the recovery of the stratosphere changed between the 2 US National Academy of Science reports on the Biological Effects from Atomic Radiation (BEAR reports) in 1956 and in 1960. Key to progressing understanding was ongoing programme of stratospheric measurements via high-altitude balloon and aircraft to monitor “in-situ” the long-lived radionuclides. During the 1958-60 moratorium on testing, no input of radioactivity, air out -- key unknown was the timescale for removal of radioactivity from the previous tests unique tracer for the circulation of air in the stratosphere, and to understand the global variation in fallout measured at ground stations worldwide US Atomic Energy Commission (AEC) US Atomic Energy Commission (AEC) established in 1946, but began part of its remit to ”develop nuclear weapons on a schedule determined by the president” in Jan 1947. From the Manhattan Project, after the war, J. Robert Oppenheimer became 1st chairman of the General Advisory Committee to the AEC, with selected panel of scientists. Major change of policy direction in the 1950s after the first Soviet nuclear test, and the huge public investment in the US to develop and test a hydrogen bomb ”super bomb”, whereby two-stage device fusion initiated via first-stage fission trigger. >1,000 times larger than Hiroshima (Mt yield) inject radioactive debris into stratosphere Willard Libby, physical chemist, highly influential research in 1940s on radiocarbon dating winning Nobel Prize in 1960, joined the AEC General Advisory Committee in 1950. The AEC’s Health and Safety Division, based in New York, was established in 1949 to assess radiation protection and safety, in 1953 renamed the Health And Safety Laboratory (HASL) set up a program of gummed film fallout measurements at US Weather Bureau sites. Merril Eisenbud appointed first Director of the HASL within the AEC in 1951 In the 1970s, the functions of the AEC were incorporated into the US Department of Energy, with HASL then becoming the DoE Environmental Measurements Laboratory (EML) More info at 1995 Merill Eisenbud interview https://ehss.energy.gov/ohre/roadmap/histories/0456/0456toc.html Excerpt from Merril Eisenbud autobiography (chapter 5, page 69) “Our studies were classified ’secret’ for a while but before long we were allowed to disseminate the information without restriction. John Harley and I prepared the first summary of our findings, which we published in Science in 1953.” “This was the first of several articles on the subject. The policy of publishing our data in the open literature was a wise one. It would have been wrong not to do so, and from a practical point of view there was no way in which the presence of radioactivity could be kept secret.” ”By the mid-1950s most research laboratories used sensitive radiation detectors, and many scientists were reporting increased in the background levels, which they realized was due to fallout from the weapons tests.” ”Some of the scientists began to complain to their elected officials who made inquiries to the AEC, and these were referred by Washington to the Health and Safety Laboratory because we had the needed information.” “Richard Nixon, Senator from California, was among those who asked for information in May 1953, when tests were in progress in Nevada. ”Reports of fallout began to be made even in Europe, and the distinguished physicist Sir John Cockcroft visited me to report his estimate of the amount of bomb debris that had deposited on the Thames Valley from the tests conducted in the fall of 1951. ”The existence of radioactive fallout from the weapons test could not, need not and should not have been kept secret.” Summary of nuclear tests and timeline to 1958 moratorium and 1963 Partial Test Ban Marvin Soroos (1997) “The Endangered Atmosphere: Preserving a Global Commons” First report of effects of radioactive fallout in the US actually from the 1st ever nuclear test, the Trinity test, in the Alamagordo desert in July 1945. Culmination of the Manhattan Project, to test the plutonium device, then detonated above Nagasaki. (Hiroshima the other fission device from uranium) X-ray film sensitive to very low concentrations of radioactivity (Kodak Eastman company) Traced to inter-leaving paper from factory in Mid-West manufacturing the packaging material. During 2nd world war similar contamination of paper previously packing radium instrument dials. Webb et al. (1949, Physical Review) Pacific Proving Grounds: Marshall Islands (1946 to 1958) First nuclear detonations in the Pacific (Crossroads, Bikini Atoll, July 1946) (*) https://bikiniatoll.com/Health%20Physics%20paper%20JMN.pdf First post-war detonations were in the US Pacific Island territory of Marshall Islands 162 people who lived on Bikini Atoll were forced to move from their homes to Rongerik atoll (see e.g. Niedenthal, 2000), see (*) The 2 Crossroads tests were plutonium fission devices, identical design as Nagasaki bomb. 1st July -- Able air drop (from B-29 aircraft) 25th July – Baker shot 90 feet underwater. Series co-ordinated by US Joint Chiefs of Staff (only 1 year after the end of the war). Aim of tests to assess impact of atomic weapon on naval fleet, 37 instrumented by empty ships in target array to demonstrate effects. Invited audience of journalists, scientists and policy makers observe from 10 n. miles away Report to JCoS (Baker) a “radioactive mist (**) https://www.newyorker.com/tech/annals-of-technology/america-at-the-atomic-crossroads descended on the target fleet larger than Synthesis of public domain government info., expected” & “ships became radioactive stoves” (Atmospheric Nuclear Weapons Testing 1951-1963, Progressive Management, 2006) Pacific Proving Grounds: Marshall Islands (1946 to 1958) (Atmospheric Nuclear Weapons Testing 1951-1963, Progressive Management, 2006) Local Fallout from Crossroads Baker shot 1985 GAO report to US senate, revision of radiation exposure estimate for service personnel https://www.gao.gov/assets/150/143931.pdf Local Fallout from Crossroads Baker shot 1985 GAO report to US senate, revision of radiation exposure estimate for service personnel https://www.gao.gov/assets/150/143931.pdf Establishing of the wider US fallout monitoring from Nevada Test Site “At the time of the Rochester fallout there was little appreciation of the fact that some of the nuclides present in the bomb debris were capable of being absorbed by plants and animals and could eventually find their way into food and the human body.” ”Such information was available from studies that had been conducted at Hanford and other nuclear centers, but the information was still secret in 1951, and at HASL we didn’t know it existed. What is disappointing in retrospect is that the Division of Biology and Medicine at AEC headquarters had paid so little attention to the matter that there were no advance preparations for fallout measurements.“ ”Immediately following the Rochester incident there was interest in this subject, but only because it was a scientific curiosity, not because the fallout should be investigated because of its public health implications.” ”HASL might not have been involved in further fallout studies were it not for the fact that Eastman Kodak needed information to protect its processes and requested the AEC to provide it with advance notice when a cloud from the weapons test was approaching one of their manufacturing facilities.” ”This request was relayed by the AEC Division of Military Applications to Wilbur Kelley, manager of the NYOO, with instructions for HASL to assist Kodak in any way possible.” Merril Eisenbud et al. “An Environmental Odyssey” (Univ. Washington Press, 1990) Establishing of the wider US fallout monitoring from Nevada Test Site “By the spring of 1951, preparations were already well underway for tets to be conducted in Nevada that fall in two parts – BUSTER, a series of explosions above ground, and JANGLE, which consisted of a surface, and an underground test.” ”Although the latter two explosions would be relatively