Abstract
Hawaii is located in the interior of the North Pacific Subtropical Gyre, making it an ideal location for capturing basin scale climate variability without the influence of continental effects. At the same time, this region also exhibits prominent local seawater mass variability driven by the trade winds. However, long-term in situ observational records of climate in this area are limited. This study aims to reconstruct sea surface temperature (SST) and nutrient variability over the past 100 years, as well as the associated seawater mass dynamics, using coral skeletons. Modern coral skeletons from windward and leeward side of Oahu, were used. Strontium-to-calcium (Sr/Ca) ratios as a SST proxy and nitrogen isotopic composition of skeletal organic matter (d15Ncoral) as a nutrient proxy, that extend back to 1908 on the windward side and 1957 on the leeward side, were obtained. In this presentation, the results of barium-to-calcium (Ba/Ca) and manganese-to-calcium (Mn/Ca) ratios in coral skeletons to investigate the characteristics and origins of local seawater masses, will be discussed.
