OXYGEN-18, DEUTERIUM, AND TRITIUM
IN NATURAL WATERS AND THEIR RELATIONS
TO THE GLOBAL CIRCULATION OF WATER
ERIK ERIKSSON and BERT BOLIN
International Meteorological Institute, University of Stockholm,
Stockholm, Sweden
ABSTRACT
The occurrence of the nuclides 18 deuterium, and tritium in natural
waters is discussed oh the basis of the general circulation of water
derived from standard meteorological observations of humidity, precipitation, and evaporation. If the establishment of a characteristic
vertical distribution of moisture, deuterium, and '%0 is rapid (a few
days) in comparison with the large-scale horizontal transfer rates of
moisture over the oceans, one can relate the vertical distribution of
deuterium and '%0 in air moisture and the content of these nuclides in
precipitation to the humidity distribution, the isotopic composition of
sea water, and the characteristic fractionation factor for condensation —
evaporation. Observed isotopic composition of rainwater and recent
measurements of tritium in atmospheric moisture over equatorial
regions are discussed in view of theoretical results. Furthermore, the
meridional transports of moisture, deuterium, and ‘80 which have the
ocean surface as the source are compared with the transfer of tritium
which has a stratospheric source. Finally, an estimate of the total in-
ventory of tritium is given and related to the global fallout of tritium.
INTRODUCTION
Extensive investigations into the transfer of moisture in the atmoSphere have been conducted during the last decade, e.g., Ref. 1. We
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