https://repository.kopri.re.kr/handle/201206/9836 2026-04-21T12:55:02Z 2026-04-21T12:55:02Z Joo, Young Ji Forwick, Matthias Park, Kwangkyu Joe, Young Jin Son, Yeong-Ju Nam, Seung-il https://repository.kopri.re.kr/handle/201206/10944 2022-03-24T07:14:05Z 2019-09-01T00:00:00Z

Title: Holocene environmental changes in Dicksonfjorden, west Spitsbergen, Svalbard Authors: Joo, Young Ji; Forwick, Matthias; Park, Kwangkyu; Joe, Young Jin; Son, Yeong-Ju; Nam, Seung-il Abstract: Multi-proxy analyses of two sediment cores from Dicksonfjorden were performed to reconstruct Holocene environmental conditions in this northern tributary of Isfjorden, the largest fjord system on Svalbard. Factors affecting the depositional processes include shifts in sources of inorganic and organic sediments, ice rafting, and regional glacio-isostatic rebound. Sediments were derived from Palaeozoic siliciclastic and carbonate bedrocks occurring at the fjord head and sides, respectively. Their relative contributions were controlled by falling relative sea-level and the resulting progradation of the major stream and delta systems closer to the core sites. Deposition of clasts from sea ice rafting persisted throughout the most of the Holocene. Following a period of low, but continuous, clast fluxes (~ c. 11 ？ 7 ka), ice rafting was most intensive between c. 7 and 3 ka. It can be related to extensive seasonal sea ice formation caused by regional climate cooling. The prograding deltas also provided coarse sediments. Reduced ice rafting from c. 3 ka suggests enhanced formation of more shorefast and/or permanent sea ice, suppressing sea ice rafting in the fjord, in response to the cool climate and reduced heat flux from Atlantic Water. Episodic inflow of Atlantic Water, however, as well as low turbidity of surface water, can account for a higher amount of marine organic matter produced in the outer fjord. The sedimentary record in Dicksonfjorden, where tidewater glaciers are absent, reflects similar regional climate and oceanographic variations as reconstructed in fjords on western Spitsbergen that are influenced by tidewater glaciers.

2019-09-01T00:00:00Z Kim, Haryun Lee, Kitack Lim, Dhong-Il Nam, Seung-il Han, Seung hee Kim, Jihun Lee, Eunil Han, In-Seong Jin, Young Keun Zhang, Yanxu https://repository.kopri.re.kr/handle/201206/10873 2022-03-24T07:14:16Z 2019-03-01T00:00:00Z

Title: Increase in Anthropogenic Mercuryin Marginal Sea Sediments of the Northwest Pacific Ocean Authors: Kim, Haryun; Lee, Kitack; Lim, Dhong-Il; Nam, Seung-il; Han, Seung hee; Kim, Jihun; Lee, Eunil; Han, In-Seong; Jin, Young Keun; Zhang, Yanxu Abstract: Over the past century, the addition of anthropogenic mercury (HgANTH) to vast areas of North Pacific marginal seas adjacent to the northeast Asian continent has tripled. Analysis of sediment cores showed that the rate of HgANTH addition (HgANTH flux) was greatest in the East China and Yellow Seas (9.1 μg m？2 yr？1) in the vicinity of China (the source continent), but was small in the Bering and western Arctic Ocean (Chukchi Sea) (0.9 μg m？2 yr？1; the regions furthest from China). Our results show that HgANTH has reached open ocean sedimentary environments over extended areas of the northwestern Pacific Ocean, via the formation of organic-mercury complexes and deposition. The implication of these findings is that the addition of HgANTH (via atmospheric deposition and riverine input) to the ocean environment is responsible for elevated Hg flux into sedimentary environments in the northwest Pacific Ocean

2019-03-01T00:00:00Z Etourneau, Johan Sgubin, Giovanni Crosta, Xavier Swingedouw, Didier Willmott, Veronica Barbara, Loic Houssais, Marie-Noelle Schouten, Stefan Damste, Jaap S. Sinninghe Goosse, Hugues Escutia, Carlota Crespin, Julien Masse, Guillaume Kim, Junghyun https://repository.kopri.re.kr/handle/201206/10879 2022-03-24T07:14:25Z 2019-01-01T00:00:00Z

Title: Ocean temperature impact on ice shelf extent in the eastern Antarctic Peninsula Authors: Etourneau, Johan; Sgubin, Giovanni; Crosta, Xavier; Swingedouw, Didier; Willmott, Veronica; Barbara, Loic; Houssais, Marie-Noelle; Schouten, Stefan; Damste, Jaap S. Sinninghe; Goosse, Hugues; Escutia, Carlota; Crespin, Julien; Masse, Guillaume; Kim, Junghyun Abstract: The recent thinning and retreat of Antarctic ice shelves has been attributed to both atmosphere and ocean warming. However, the lack of continuous, multi-year direct observations as well as limitations of climate and ice shelf models prevent a precise assessment on how the ocean forcing affects the fluctuations of a grounded and floating ice cap. Here we show that a +0.3-1.5 degrees C increase in subsurface ocean temperature (50-400 m) in the northeastern Antarctic Peninsula has driven to major collapse and recession of the regional ice shelf during both the instrumental period and the last 9000 years. Our projections following the representative concentration pathway 8.5 emission scenario from the Fifth Assessment Report of the Intergovernmental Panel on Climate Change reveal a +0.3 degrees C subsurface ocean temperature warming within the coming decades that will undoubtedly accelerate ice shelf melting, including the southernmost sector of the eastern Antarctic Peninsula.

2019-01-01T00:00:00Z Kim, Dahae Kim, Jung-Hyun Kang, Sujin Park, Kwangkyu Lee, Dong-Hun Jin, Young Keun Nam, Seung-il Shin, Kyung-Hoon https://repository.kopri.re.kr/handle/201206/12280 2022-03-24T07:15:23Z 2019-01-01T00:00:00Z

Title: Tracing terrestrial organic matter in two contrasting Arctic systems: A case study in the Mackenzie Trough in the Canadian Beaufort Sea and in Wijdefjorden in the Svalbard Archipelago Authors: Kim, Dahae; Kim, Jung-Hyun; Kang, Sujin; Park, Kwangkyu; Lee, Dong-Hun; Jin, Young Keun; Nam, Seung-il; Shin, Kyung-Hoon Abstract: The Arctic is warming twice as fast as other parts of the Earth by thawing permafrost and thus mobilizing the organic carbon (OC) stored in permafrost. With ongoing climate changes, inputs of terrestrial OC into the Arctic Ocean have been expected to increase through several pathways including river discharges, coastal erosions, and glacial discharges. In order to understand the Arctic carbon cycle, knowledge of OC dynamics with various regional characteristics is essential. The Mackenzie River, which flows into the Beaufort Sea, is the fourth-largest Arctic river in terms of freshwater discharge, but the first in terms of sediment discharge. Wijdefjorden is the longest fjord in Svalbard archipelago, located in the northern portion of the island of Spitsbergen, which supplies glacigenic terrestrial material through glacial discharges. In this study, two contrasting Arctic environments were investigated using surface sediments collected along Mackenzie Trough and Wijdefjorden during the expeditions of the R/V ARAON (ARA04C, ARA05C, and ARA08C in 2013, 2014, and 2017) and R/V Helmer Hanssen (HH17 in 2017), respectively. We analyzed the samples for bulk (e.g. Corg/Norg ratio, δ13Corg, and δ15Norg) and molecular (concentrations and δ13C of n-alkanes) parameters to assess sources of organic matter. In addition, we analyzed the radiocarbon content (Δ14C) to evaluate the contribution of fossil and non-fossil to the overall OC pool of OC. Our results will provide information on the contribution of organic carbon to the thawing of terrestrial permafrost in the two contrasting Arctic environmental systems.

2019-01-01T00:00:00Z