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Browsing by Author "Spedding, David John"

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    The application of radio-isotopes to botanical problems
    (Te Herenga Waka—Victoria University of Wellington, 1962) Spedding, David John
    The presence of bomb-carbon-14 in the atmosphere gives a unique opportunity to study a variety of biological problems, using the increase of carbon-14 as a means of short-term dating. THE PRODUCTION OF BOMB CARBON The C14O2 concentration in the atmosphere has shown a considerable increase since 1954 as is illustrated in Figure 1 which shows the rate of increase of C14 activity for the Southern hemisphere(1). Nuclear explosions have resulted in the formation of C14 which was carried up to the stratosphere by the heat associated with the explosion. The diffusion of this C14 back into the atmosphere has caused the large increase in the atmospheric C14. Between 1954 and the present time the increase in the specific activity of the atmospheric CO2 has been in excess of 20%. The Northern hemisphere shows an even larger effect.