碩士 / 國立臺灣海洋大學 / 地球科學研究所 / 107 / The sea surface temperature (SST) is a key climate component in the subarctic Pacific, reflecting mainly the heat and gas exchange between the ocean and the atmosphere, the covers of seasonal sea ice, and ocean circulation pattern changes. In this study I analyzed organic biomarker SST proxy, the alkenone unsaturation ratios (UK'37) from core LV 63-23-2 (176.45° E,61.08° N, depth of 1889m, length 4.06 m) retrieved from a high sedimentation continental slope of northern Aleutian basin and analyze/compile a total of 52 core top alkenone data from northwest Pacific and Bering sea. This study aims to evaluate regional against global calibrations of UK'37 using the subarctic coretop samples. The results of this study show that the subarctic UK'37-SSTs are mainly driven by SSTs of warm seasons, which in turn, are biased by the seasonality sea ice cover expansion/contraction. Based on the SST estimates and sea ice cover linkages, this study indicates that since the Last Glacial Maximum (LGM), and the extremely cold periods (Heinrich Stadial 1, HS 1; and Younger Dryas, YD), the Bering sea has been sea ice covered. In contrast, reduced sea ice cover or ice-free conditions has prevailed during warmer intervals (e.g. Bølling/Allerød, B/A and Early Holocene). The patterns of the SST and sea ice cover changes suggest an atmospheric teleconnection between North Pacific and North Atlantic. In particular, this study shows that after the opening of the oceanic gateways of the Bering Strait and Aleutian Archipelago, increased warm current intrusions with an insolation maximum from 11 ka, the SSTs have reached maxima in the Bering Sea.
| Identifer | oai:union.ndltd.org:TW/107NTOU5135004 |
| Date | January 2019 |
| Creators | Chen, Chih-Yin, 陳稚穎 |
| Contributors | Chen, Min-Te, 陳明德 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 40 |
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