Institute of Low Temperature Science, Hokkaido University, Kita-19, Nishi-8, Kita-ku, Sapporo 060-0819
Institute of Low Temperature Science, Hokkaido University, Kita-19, Nishi-8, Kita-ku, Sapporo 060-0819
Institute of Low Temperature Science, Hokkaido University, Kita-19, Nishi-8, Kita-ku, Sapporo 060-0819
National Institute of Polar Research, Research Organization of Information and Systems, Midori-cho 10-3, Tachikawa, Tokyo 190-8518
The stable oxygen isotope ratio(δ^<18>O) in precipitation is known to have important meridional and seasonal variations, but there are almost no measurements of δ^<18>O in precipitation over polar oceans. The present research took advantage of 4 opportunities for in situ observations in summer and winter at high latitudes in the Southern Ocean. In addition, we analyzed samples of precipitation at Syowa Station in 2008 to obtain year-round data. Based on these data, we consider the meridional and seasonal variations of δ^<18>O in precipitation over the Southern Ocean. In general, δ^<18>O decreases with increasing latitude, and is lower in winter than in summer. The latitude gradient is stronger in winter. At 60°S, δ^<18>O is -5.4‰ and -11.3‰ in summer and winter, respectively, while the corresponding figures at 66°S are -10.5‰ and -20.8‰. These results will help us understand the mechanisms of the salinity distribution and its variation in the Antarctic Ocean.
南大洋における降雪の酸素安定同位体比の緯度分布と季節変化
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KJ00006477860
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概要
