Nuclear weapons testing in the

Nuclear weapons testing in the atmosphere introduced excess l4C that has proven to be an excellent tracer for processes that will be important in the uptake of fossil fuel CO2. For example, Peng (1986) mapped global uptake patterns of excess 14C and used these to calculate fossil fuel CO2 uptake by the oceans. His results indicate that about 10% of the fossil fuel CO2 is "missing". In the next chapter we will discuss the possibility that this missing CO2 may be the result of dissolution of highly soluble magnesian calcites from shallow water sediments. Also, Feely and... 

Assuming that the system is at steady state, the mass of from the atmosphere must be balanced by decay of in the water column. An estimate of the global annual mean value for feco2 of 21 5 cm h can therefore be produced by a budgeting technique (Broecker et al., 1986). Similarly, by measuring the increased present in the oceans as a result of atmospheric nuclear weapon tests in the middle of the twentieth century, an independent estimate of kco of 22 3 cmh can be derived (Broecker et al., 1986), in very good agreement with the natural... 

A few of the nuclear weapon tests in the Pacific Ocean were conducted by the USA outside the Marshall Islands, near Johnston Atoll and Christmas Island (the latter Kiribati, formerly the Gilbert Islands) however, these tests were limited to high altitude explosions. 

Nuclear weapon testing in the Marshall Islands was terminated in July 1958. On 31 October 1958, the USSR, the United Kingdom and the USA suspended atmospheric nuclear weapon testing under an international moratorium. The Treaty Banning Nuclear Weapon Tests in the Atmosphere, in Outer Space and Under Water was signed in Moscow on 5 August 1963. 

FIGURE 14.1 Atmospheric 14C concentration as reflected in tree rings and the bomb curve arising due to atmospheric nuclear weapon tests in the 1950s and 1960s. (Adapted from Palmblad, M. et at., J. Mass Spectrom., 40, 154, 2005. With permission.)... 

Nuclear weapon tests in the atmosphere from 1945 to 1980 have caused the greatest man-made release of radioactive material to the environment. The most intensive nuclear weapon tests took place before 1963 when a test-ban treaty signed by the UK, USA and USSR came into force. France and China did not sign the treaty and continued some atmospheric tests, but after 1980 no atmospheric tests have taken place. 

In the past, radioanalytical chemistry laboratories processed samples resulting from monitoring nuclear weapons development facilities, fallout from nuclear weapon tests in the atmosphere, and nuclear power stations. At present, monitoring cleanup of former nuclear facilities is a major source of samples, and efforts are... 

Cesium-137 in the environment came from a variety of sources. The largest single source was fallout from atmospheric nuclear weapons tests in the 1950s and 1960s, which dispersed and deposited cesiura-137 world-wide. However much of the cesium-137 from testing has now decayed. 

October The Treaty Banning Nuclear Weapon Tests in the... 

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