The trends of global tritium precipitations.

摘要: The trends of global tritium precipitation from 1953 to 1979 were estimated based on the data published in seven volumes Environmental Isotope Data by International Atomic Energy Agency (IAEA). Tritium samples collected 342 stations world and concentrations measured IAEA 27 laboratories. Due repeated atomospheric nuclear explosions, precipitations showed maximum peak 1963. After agreement Partial Test Ban Treaty 1964, they have gradually decreased until now showing seasonal variations. To obtain clear precipitations, irregular factors eliminated original time-series using a code developed Japanese Economic Planning Agency. Results analyses as follows; a) Peak observed every year around period late spring summer. b) annual concentration 1963 for northern hemisphere stations. c) A latitude effect was hemisphere. seen at approximately 50°N. d) Continental always higher than comparable maritime