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Jan.— Dec.
Jan.— Dec.
Jan.— Dec.
1961
1962
1963
(a)
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Jan.— Dec.
Jan.— Dec.
1961
1962
1963
(b)
Fig. 7—Tritium fallout in the Pacific.
than the concentration values. This indicates that the amount of precipitation at a given site affects the concentration to some extent.
The effect of altitude is observed at several locations. Generally,
the tritium concentration in precipitation increases with altitude. An
example is provided by Srinagar, India (at an altitude of 5250 ft), which
reports the highest average tritium values measured in India by the
Tata Institute. The level for the spring of 1963 at Srinagar averaged
3660 T.U., which was higher than that at Chicago. Amritsar in the same
region of North India but at a lower elevation (about 600 ft) has shown
lower tritium concentrations. For example, in the last half of 1962,
Srinagar averaged 479 T.U. whereas Amritsar averaged 202 T.U.