THATCHER, PAYNE, AND CAMERON Loti ) PYTTTETTP PP TPT PrP rrrr Ty ypr rrr ry bibs oj) pd iit 662 — ® CHICAGO - © FLAGSTAFF a [ a WACO a oh = Lede tp Jan.— Dec. Jan.— Dec. Jan.— Dec. 1962 1963 1964 (a) VeTTT TTT TT TTT TTT TTT TTT — — wee D> e = - — + — of 1? & = © OCALA — oO HATTERAS — 10! = > @ SANTA MARIA a am Lede t eri ti tiyitiz¢riper tedster teri ys Jan.— Dec. Jan.— Dec. Jan.— Dec. 1962 1963 1964 (b) Fig. 9—Tritium fallout in the United States. locations. In the southern hemisphere the preponderance of ocean over land makes a clear-cut identification of an altitude effect uncertain. Tritium data from the southern hemisphere (Fig. 2) are very limited as compared to those from the northern hemisphere. Sustained records are available only for two or three stations in South Africa (S)

Select target paragraph3