• Korean Journal of Remote Sensing
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• v.31 no.4
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• pp.347-351
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• 2015

Sea ice is a key parameter for understanding the climate change in cryosphere. In this study, we investigated the correlation with the factors that influenced change of the sea ice extent. We used the Sea Ice Concentration (SIC) from Ocean and Sea Ice Satellite Application Facility (OSI-SAF), and surface albedo provided by The Satellite Application Facility on Climate Monitoring (CM SAF). We converted the same temporal and spatial resolution of the data and detected the sea ice using SIC data. We performed the relationship analysis between SIC and sea ice albedo. As a result, we found they have a strong positive correlation. We performed the linear regression between SIC and sea ice albedo, and found they have high-level coefficient of determination. It shows using either SIC or sea ice albedo is possible to estimate the sea ice products.

• Proceedings of the KSRS Conference
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• 1998.09a
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• pp.70-75
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• 1998

The comparison of Topex/Poseidon sea surface heights and Tide Gauge sea levels was studied in the South Indian Ocean after Topex/Poseidon mission of about 3 years (11- 121 cycles) from January 1993 through December 1995. The user's handbook (AVISO) for sea surface height data process was used in this study Topex/Poseidon sea suface heights ($\zeta$$^{T/P}$), satellite data at the point which is very closed to Tide Gauge station, were chosen in the same latitude of Tide Gauge station. These data were re-sampled by a linear interpolation with the interval of about 10 days, and were filtered by the gaussian filter with a 60 day-window. Tide Gauge sea levels ($\zeta$$^{Argos}$, $\zeta$$^{In-situ}$ and $\zeta$$^{Model}$), were also treated with the same method as satellite data. The main conclusions obtained from the root-mean-square and correlation coefficient were as follows: 1) to Produce Tide Gauge sea levels from bottom pressure, in-situ data of METEO-FRANCE showed very good values against to the model data of ECMWF and 2) to compare Topex/Poseidon sea surface heights of Tide Gauge sea levels, the results of the open sea areas were better than those of the coast and island areas.

• Journal of the korean society of oceanography
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• v.35 no.4
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• pp.161-169
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• 2000

A seasonal circulation in the East China Sea and the Yellow Sea and its possible cause have been studied with CSK data during 1965-1989. Water mass distributions are clear in winter, but not in summer because the upper layer waters are quite influenced by atmosphere. To solve the problem, a water mass analysis by mixing ratio is used for the lower layer waters. The results show that the distribution of Tsushima Warm Current Water expands to the Yellow Sea in winter and retreats to the East China Sea in summer. It means that there is a very slow seasonal circulation between the East China Sea and the Yellow Sea: Tsushima Warm Current Water flows into the Yellow Sea in winter and coastal water flows out of the Yellow Sea in summer. By the circulation, the front between Tsushima Warm Current Water and coastal water moves toward the shelf break in summer so that the flow is faster in the deeper region. The process eventually makes the transport in the Korea Strait increase. The Kuroshio does not seem to influence the process. A possible mechanism of the process is the seasonal change of sea surface slope due to different local effects of surface heating and diluting between the East China Sea and the Yellow Sea.

• Ocean and Polar Research
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• v.44 no.1
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• pp.69-82
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• 2022

The Ross Sea, Antarctica plays an important role in the formation of Antarctic Bottom Water (AABW) which is the densest water mass in global thermohaline circulation. Of the AABW, 25% is formed in the Ross Sea, and sea ice formation at the polynya (ice-free area) developed in front of ice shelves of the Ross Sea is considered as a pivotal mechanism for AABW production. For this reason, monitoring the Ross Sea variations is very important to understand changes of global thermohaline circulation influenced by climate change. In addition, the Ross Sea is also regarded as a natural laboratory in investigating ice-ocean interactions owing to the development of the polynya. In this article, I introduce characteristics of the Ross Sea described in previous observational studies, and investigate variations that have occurred in the Ross Sea in the past and those taking place in the present. Furthermore, based on these observational results, I outline variations or changes that can be anticipated in the Ross Sea in the future, and make an appeal to researchers regarding the importance and necessity of continuous observations in the Ross Sea.

• Journal of the korean society of oceanography
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• v.39 no.1
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• pp.1-13
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• 2004

The Yellow Sea Warm Current (YSWC) and the Yellow Sea Cold Bottom Water (YSCBW) are two protruding features, which have strong influence on the community structure and distribution of zooplankton in the Yellow Sea. Both of them are seasonal phenomena. In winter, strong north wind drives southward flow at the surface along both Chinese and Korean coasts, which is compensated by a northward flow along the Yellow Sea Trough. That is the YSWC. It advects warmer and saltier water from the East China Sea into the southern Yellow Sea and changes the zooplankton community structure greatly in winter. During a cruise after onset of the winter monsoon in November 2001 in the southern Yellow Sea, 71 zooplankton species were identified, among which 39 species were tropical, accounting for 54.9 %, much more than those found in summer. Many of them were typical for Kuroshio water, e.g. Eucalanus subtenuis, Rhincalanus cornutus, Pareuchaeta russelli, Lucicutia flavicornis, and Euphausia diomedeae etc. 26 species were warm-temperate accounting for 36.6% and 6 temperate 8.5%. The distribution pattern of the warm water species clearly showed the impact of the YSWC and demonstrated that the intrusion of warmer and saltier water happened beneath the surface northwards along the Yellow Sea Trough. The YSCBW is a bottom pool of the remnant Yellow Sea Winter Water resulting from summer stratification and occupy most of the deep area of the Yellow Sea. The temperature of YSCBW temperature remains ${\leq}{\;}10^{\circ}C$ in mid-summer. It is served as an oversummering site for many temperate species, like Calanus sinicus and Euphaisia pacifica. Calanus sinicus is a dominant copepod in the Yellow Sea and East China Sea and can be found throughout the year with the year maximum in May to June. In summer it disappears in the coastal area and in the upper layer of central area due to the high temperature and shrinks its distribution into YSCBW.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.3
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• pp.368-373
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• 1999

Topex/Poseidon sea surface heights are compared to tide gauge sea levels in the South Indian Ocean in the period of January 1993 to December 1995. A user's handbook (AVISO) for processing sea surface height data was used in this study. Topex/Poseidon sea surface heights were obtained from satellite data at the proximity of tide gauge stations. These data were reproduced by a linear interpolation with the interval of 10 days and were processed by the Gaussian filter with a 60-day window. The tide gauge sea levels were obtained in the same manner as the satellite data. The main results on RMS (Root-Mean-Square) and CORR (CORRelation coefficient) in our study were shown as follows: 1) on the characteristics between two data (in-situ and model data), the results (RMS=2.96 cm & CORR=$92\%$ in the Amsterdam plateau, and RMS=3.45 cm & CORR=$59\%$ in the Crozet plateau) of the comparison of Topex/Poseidon sea surface heights with tide gauge sea levels, which was calculated by in-situ data of obsewed station showed generally low values in RMS and high values in CORR against to the results (RMS=4.69 cm & CORR=$79\%$ in the Amsterdam plateau, and RMS= 6.29 cm & CORR= $49\%$ in the Crozet plateau) of the comparison of Topex/Poseidon sea surface heights with tide gauge sea levels, which was calculated by model data of ECMWF (European Center for Medium-range Weather Forecasting), and 2) on the characteristics between two areas (Kerguelen plateau and island), the results (RMS=3.28 cm & CORR= $54\%$ in the Kerguelen plateau) of open sea area showed low values in RMS and high values in CORR against to the results (RMS= 5.71 cm & CORR=$38\%$ in the Kerguelen island) of coast area, respectively.

• Proceedings of the KSRS Conference
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• 1998.09a
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• pp.76-82
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• 1998

Increase of greenhouse gas due to $CO_2$ and CH$_4$ gases would cause the global warming in the atmosphere. According to the global circulation model, it is pointed out in the Okhotsk Sea that the large increase of atmospheric temperature might be occurredin this region by global warming due to the doubling of greenhouse effectgases. Therefore, it is very important to monitor the sea ice extents in the Okhotsk Sea. To improve the sea ice extents and concentration with more highly accuracy, the field experiments have begun to comparewith Airborne Microwave Radiometer (AMR) and video images installed on the aircraft (Beach-200). The sea ice concentration is generally proportional to the brightness temperature and accurate retrieval of sea ice concentration from the brightness temperature is important because of the sensitivity of multi-channel data with the amount of open water in the sea ice pack. During the field experiments of airborned AMR the multi-frequency data suggest that the sea ice concentration is slightly dependending on the sea ice types since the brightness temperature is different between the thin and small piece of sea ice floes, and a large ice flow with different surface signatures. On the basis of classification of two sea ice types, it is cleary distinguished between the thin ice and the large ice floe in the scatter plot of 36.5 and 89.0GHz, but it does not become to make clear of the scatter plot of 18.7 and 36.5GHz Two algorithms that have been used for deriving sea ice concentrations from airbomed multi-channel data are compared. One is the NASA Team Algorithm and the other is the Bootstrap Algorithm. Intrercomparison on both algorithms with the airborned data and sea ice concentration derived from video images bas shown that the Bootstrap Algorithm is more consistent with the binary maps of video images.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.11a
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• pp.49-50
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• 2014

Dredged sea soil contains various contaminants. First priority to recycle dredged sea soil is to pretreat it to remove various contaminants because recycling dredge sea soil without any pre-treatment may cause a secondary contamination due to the leaching of hazardous chemicals. In this study, pretreated dredged sea soil was used to investigate pozzolanic activity. The properties of pretreated dredged sea soil were investigated, the method for heat treatment was determined, and the compressive strength of mortar using dredged sea soil was examined to evaluate pozzolanic activity. According to the results, pretreated dredged sea soil has some possibility to work as a pozzolanic material. When dredged sea soil was heat treated for 90min at 550℃, compressive strength was shown to be comparable to that of plain cement mortar.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.5
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• pp.1380-1394
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• 2015

This paper deals with the geographical scope of the East Sea introduced by major domestic institutions. The East Sea surrounded by South Korea, North Korea, Russia, Japan has a variety of marine resources, and is the very appropriate natural laboratory to study future global changes as a miniature ocean. However, there is a continuous conflict between Korea and Japan over the name of the East Sea because of the nature of international waters. So we need the active research achievements based on the exact geographic knowledge of the East Sea to promote the legitimacy of the East Sea in the international community. Nevertheless each domestic institution has a different way to define the southern border of the East Sea so that it showed a difference about linear distance of up to about 44 km. Also, they have defined the scope of East Sea not as the entire East Sea surrounded by South Korea, North Korea, Russia and Japan but as the jurisdiction of the Republic of Korea. It caused serious confusion about accurate statistical knowledge about East Sea such as area, volume, and mean water depth. Therefore, clear social consensus about the geographical scope of the East Sea would be required, there is also the need to institutionalize a legal order to spread it.

• Korean Journal of Pharmacognosy
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• v.41 no.4
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• pp.308-312
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• 2010

The purpose of this research is to provide basic informations to discriminate between sea buckthorn (Hippophae rhamnoides) cultivated in the Republic of Korea and Mongolia. The phenolic compounds of sea buckthorn, were measured by the HPLC analysis. Catechin, rutin, quercetin, isorhamnetin were found in methanol extracts of sea buckthorn. Total phenolic compound of Korean sea buckthorn leaves (1.852%) was about five times higher than those of Mongolian sea buckthorn berries (0.338%). As a result, the order of the total phenolic compound and Catechin content was 1) sea buckthorn leaves, 2) sea buckthorn stems, 3) sea buckthorn roots, and 4) sea buckthorn berries. Statistically no big differences in levels of phenolic compounds were consistently found in sea buckthorn cultivated in the Republic of Korea and Mongolia investigated in this work.