• Journal of Environmental Science International
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• v.26 no.12
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• pp.1363-1374
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• 2017

Global climate change caused by industrialization has caused abnormal weather conditions such as urban temperatures and tropical nights, urban heat waves, heat waves, and heavy rains. Therefore, the study tried to analyze climate conditions and weather conditions in the streets and analyze climate factors and meteorological factors that lead to inconvenience to citizens. In the case of trees, the overall temperature, surface temperature, solar irradiance, and net radiation were measured low, and the temperature was lower in the Pedestrian road than in roads. The dry bulb temperature, the black bulb temperature, and the wet bulb temperature for the thermal evaluation showed the same tendency. In the case of thermal evaluation, there was a similar tendency to temperature in WBGT, MRT, and UTCI, and varied differences between types. Although the correlation between the meteorological environment and the thermal environment showed a statistically significant significance, the difference between the measured items was not significant. The study found that the trees were generally pleasant to weather and thermal climate in the form of trees, and the differences were mostly documented.

• Journal of Astronomy and Space Sciences
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• v.36 no.3
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• pp.149-157
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• 2019

In this study, we investigate the associations between the solar variability and teleconnection indices, which influence atmospheric circulation and subsequently, the spatial distribution of the global pressure system. A study of the link between the Sun and a large-scale mode of climate variability, which may indirectly affect the Earth's climate and weather, is crucial because the feedbacks of solar variability to an autogenic or internal process should be considered with due care. We have calculated the normalized cross-correlations of the total sunspot area, the total sunspot number, and the solar North-South asymmetry with teleconnection indices. We have found that the Southern Oscillation Index (SOI) index is anti-correlated with both solar activity and the solar North-South asymmetry, with a ~3-year lag. This finding not only agrees with the fact that El $Ni{\tilde{n}}o$ episodes are likely to occur around the solar maximum, but also explains why tropical cyclones occurring in the solar maximum periods and in El $Ni{\tilde{n}}o$ periods appear similar. Conversely, other teleconnection indices, such as the Arctic Oscillation (AO) index, the Antarctic Oscillation (AAO) index, and the Pacific-North American (PNA) index, are weakly or only slightly correlated with solar activity, which emphasizes that response of terrestrial climate and weather to solar variability are local in space. It is also found that correlations between teleconnection indices and solar activity are as good as correlations resulting from the teleconnection indices themselves.

• Journal of Ecology and Environment
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• v.38 no.4
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• pp.599-609
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• 2015

A total of 19 species of three genera Dinophysis, Histioneis, and Parahistioneis of the family Dinophysaceae are reported here from samples obtained using a 20-µm mesh net from June 2006 to December 2014 around Jeju Island including the East China Sea, and 16 of these species are new to Korean waters. A checklist of the three genera of dinoflagellates reported from coastal and oceanic Korean waters is presented. Short descriptions and synonyms are given for each species. The dinoflagellates of the family Dinophysaceae belong to mostly marine species, and include many tropical and/or subtropical species. Recently, the composition of dinoflagellate species has changed around Jeju Island as well as in Korean waters due to global warming and climate change. Tropical and subtropical dinoflagellates occur frequently in the coastal waters of Jeju Island, which reflects the ecosystem shift around the sea adjacent to Jeju Island from a temperate to a subtropical / tropical region.

• Ocean and Polar Research
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• v.35 no.4
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• pp.351-353
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• 2013

Until recently, Pacific equatorial tropical island states were subject of only very limited interest by scientists, government officials, industry and policy makers of Korea. And, comprehensive information and data on these island regions is not very detailed to help better understand their social backgrounds as well as their natural environment. However, these island regions are now in the middle of diplomatic tug-of-war among super powers as well as becoming nucleus of various science-based ocean issues including marine biodiversity, shifting ecosystem, global environmental change including sea level rise and ocean acidification, fisheries, etc. Therefore, rising political and scientific importance of these areas call for better understanding of these regions, in social aspects as well as natural scientific knowledge of the region. To be provocatively prepared to more actively role in these regions, "A study on Establishing Research Infrastructures in the Tropical Pacific" has been supported during 2012-2013 as a mission-oriented in-house project of the KIOST. This project aims to provide various research infrastructure for Pacific island states, to reinforce cooperation with these nations, and to enhance Korea's national prestige. This special issue contains 10 research articles based on the studies conducted in 2012~2013.

• Journal of the Korean earth science society
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• v.42 no.4
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• pp.390-400
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• 2021

Ocean biogeochemistry plays a crucial role in sustaining the marine ecosystem and global carbon cycle. To investigate the oceanic biogeochemical responses to iron parameters in the tropical Pacific, we conducted sensitivity experiments using the Nucleus for European Modelling of the Ocean-Tracers of Ocean Phytoplankton with Allometric Zooplankton (NEMO-TOPAZ) model. Compared to observations, the NEMO-TOPAZ model overestimated the concentrations of chlorophyll and dissolved iron (DFe). The sensitivity tests showed that with increasing (+50%) iron scavenging rates, chlorophyll concentrations in the tropical Pacific were reduced by approximately 16%. The bias in DFe also decreased by approximately 7%; however, the sea surface temperature was not affected. As such, these results can facilitate the development of the model tuning strategy to improve ocean biogeochemical performance using the NEMO-TOPAZ model.

• Journal of Forest and Environmental Science
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• v.37 no.2
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• pp.128-140
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• 2021

Tropical dry forests are one of the most threatened, widely distributed ecosystems in tropics and estimation of forest biomass is a crucial component of global carbon emission estimation. Therefore, the present study was aimed to quantify the biomass and carbon storage in trees on large scale (10, 1 ha plots) in the dry mixed evergreen forest of Javadhu forest of Eastern Ghats. Biomass of adult (≥10 cm DBH) trees was estimated by non-harvest methods. The total biomass of trees in this tropical dry mixed evergreen forest was ranged from 160.02 to 250.8 Mg/ha, with a mean of 202.04±24.64 Mg/ha. Among the 62 tree species enumerated, Memecylon umbellatum accumulated greater biomass and carbon stocks (24.29%) more than the other species in the 10 ha study plots. ANOVA revealed that there existed a significant variation in the total biomass and carbon stock among the three plant types (Evergreen, brevi-deciduous and deciduous (F (2, 17)=15.343, p<0.001). Basal area and density was significant positively correlated with aboveground biomass (R² 0.980; 0.680) while species richness exhibited negative correlation with above ground biomass (R² 0.167). Finding of present study may be interpreted as most of the trees in this forest are yet to be matured and there is a net addition to standing biomass leading to carbon storage.

• Ocean Systems Engineering
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• v.12 no.1
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• pp.39-61
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• 2022

Renewable energy such as wave energy has gained popularity as a means of reducing greenhouse gases. However, the high cost and lack of available sea space in some countries have hindered the deployment of wave energy converters (WEC) as alternative means of sustainable energy production. By combining WECs with infrastructures such as floating breakwaters or piers, the idea of electricity generated from WECs will be more appealing. This paper considers the integration of vertical raft-type WEC (commonly known as the vertical flap WEC) with floating breakwater as means to generate electricity and attenuate wave force in the tropical sea. An array of 25 WECs attached to a floating breakwater is considered where their performance and effect on the wave climate are presented. The effects of varying dimensions of the WEC and mooring system of the floating breakwater have on the energy generation are investigated. The integrated WECs and floating breakwater is subjected to both the regular and irregular waves in the tropical sea to assess the performance of the system. The result shows that the integrated vertical flap-floating breakwater system can generate a substantial amount of wave energy and at the same time attenuate the wave force effectively for the tropical sea when optimal dimensions of the WECs are used.

• Proceedings of the KSRS Conference
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• 2004.10a
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• pp.178-181
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• 2004

The Tropical Rainfall Measuring Mission (TRMM) is an US-Japan joint space mission to observe tropical and subtropical rainfall. This satellite is equipped with the world's first precipitation radar that operates at 13.8 GHz. We introduce the TRMM precipitation radar (PR) system, along with the PR data processing and analysis algorithms, and some observation results obtained by the TRMM PR. It is concluded that the TRMM PR can give quite useful rainfall data for the understanding of global climate changes, meteorology, climatology, atmospheric science, and also for the studies of satellite communication.

• 한국데이터정보과학회:학술대회논문집
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• 2002.06a
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• pp.9-15
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• 2002

This paper presents the seasonal forecasting of the occurrence of tropical cyclone (TC) over Western North Pacific (WNP) using the generalized linear model (GLM) and dynamic linear model (DLM) based on 51-year-data (1951-2001) in TC season (June to November). The numbers of TC and TY are predictands and 16 indices (the E1 Nino/Southern Oscillation, the synoptic factors over East asia and WNP) are considered as potential predictors. With 30-year moving windowing, the estimation and prediction of TC and TY are performed using GLM. If GLM forecasts have some systematic error like a bias, DLM is applied to remove the systematic error in order to improve the accuracy of prediction.

• Ocean and Polar Research
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• v.35 no.3
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• pp.249-258
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• 2013

Vertical and horizontal mixing processes in the ocean mixed layer determine sea surface temperature and temperature variability. Accordingly, simulating these processes properly is crucial in order to obtain more accurate climate simulations and more reliable future projections using an ocean general circulation model (OGCM). In this study, by using Modular Ocean Model version 4 (MOM4) developed by Geophysical Fluid Dynamics Laboratory, the upper ocean temperature and mixed layer depth were simulated with two different vertical mixing schemes that are most widely used and then compared. The resultant differences were analyzed to understand the underlying mechanism, especially in the Tropical Pacific Ocean where the differences appeared to be the greatest. One of the schemes was the so-called KPP scheme that uses K-Profile parameterization with nonlocal vertical mixing and the other was the N scheme that was rather recently developed based on a second-order turbulence closure. In the equatorial Pacific, the N scheme simulates the mixed layer at a deeper level than the KPP scheme. One of the reasons is that the total vertical diffusivity coefficient simulated with the N scheme is ten times larger, at maximum, in the surface layer compared to the KPP scheme. Another reason is that the zonal current simulated with the N scheme peaks at a deeper ocean level than the KPP scheme, which indicates that the vertical shear was simulated on a larger scale by the N scheme and it enhanced the mixed layer depth. It is notable that while the N scheme simulates a deeper mixed layer in the equatorial Pacific compared to the KPP scheme, the sea surface temperature (SST) simulated with the N scheme was cooler in the central Pacific and warmer in the eastern Pacific. We postulated that the reason for this is that in the central Pacific atmospheric forcing plays an important role in determining SST and so does a strong upwelling in the eastern Pacific. In conclusion, what determines SST is crucial in interpreting the relationship between SST and mixed layer depth.