offer the opportunity to quantify the different roles of the three factors mentioned above.
We analyzed the effect on the AL through atmospheric changes caused by the reduction of sea ice concentration in the Okhotsk Sea and Arctic Sea ice loss by global warming. SLP change due to the reduction of sea ice in the Okhotsk sea showed NPO pattern, which is increased SLP over the Bering sea and decreased SLP spread in the Okhotsk Sea to the North Pacific. In contrast, SLP change due to the Arctic sea ice loss showed a PNA pattern which is a negative anomaly in the Bering sea and positive anomaly in eastern Japan. Through this difference SLP change pattern, sea ice loss can be a clue that led to a change of SLP. The reduction in Arctic sea ice due to global warming make weakened zonal wind in high-latitude and strengthen zonal wind in mid-latitude. The change of zonal wind’s strength and position affect AL. Also, warmer SAT and SST and increased precipitation affect the interaction between ocean and atmosphere and change the North Pacific climate.
Deser et al. (2016) examine only the sea ice loss induced portion of climate change, not a full response to Global warming. However, this study considered all changes by global warming not only the sea ice loss effect but also other factors.
As a result, other factors can affect the atmospheric circulation in this study.
Therefore, further work is needed to assess the impact of sea ice loss in other areas and use only atmospheric model simulation to confirm the atmospheric dynamics.
Dynamical mechanisms that drive the deepening of the AL, however, were not examined in this study and should be the subject of further studies with additional numerical experiments on atmospheric response. In addition, further studies including numerical experiments on atmospheric response are also needed to understand the mechanism by which SIC change drives the deepening of the AL as well as other factors, which have not been considered in this study, such as local
changes in SST, SAT, humidity, changes in dynamics, or remote teleconnections from the tropics.
Acknowledgements
I would first like to thank Prof. Ho-Jin Lee for his guidance, and advice. He allows me to do research and providing invaluable guidance throughout this research. He taught me the methodology to carry out the research and to present the research works as clearly as possible. It was a great privilege and honor to work and study under his guidance.
My sincere thanks also go to Dr. Young-Gyu Park and Prof. Hyeong-Seong Kim for their critical review and comments for my Master thesis. I would also like to acknowledge Dr. Wonsun Park of the GEOMAR Helmholtz Centre for Ocean Research Kiel. I am gratefully indebted to his valuable comments and support on this thesis. And I am grateful to Prof. Kideok Do. His office was always open whenever I ran into a trouble spot or had a question about my research.
I thank my senior Mi Ok Kwon, Sang-Yeob Kim, and Eun Sun Lee. I was able to do my master’s degree not only studying models but also giving helpful advice to my life. Also, I thank my friends, Gun Woo Do, Min Hwa Jeong, Hae Seung Jeong, and KMI interns. And I would like to thank Soo-Jin Park for her help in school.
Finally, I must express my very profound gratitude to my parents for providing me with unfailing support and continuous encouragement throughout my years of study and through the process of researching and writing this thesis. This accomplishment would not have been possible without them. Thank you.
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