• Journal of the Korean Geographical Society
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• v.38 no.4
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• pp.463-477
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• 2003

This study identified the effects of global temperature rise on snowfall change over Korea selecting Seoul, Gangneung, Gunsan, and Daegu as study areas. The trend of snowfall change has generally decreased since 1950s over Korea, but has only increased in Gunsan since 1990s. The variation of snowfall days are similar to those of snowfall. The relationship between snowfall over Korea and the anomaly of global mean temperature in spring has a negative correlation. The change of Siberian High intensity also has a good relationship with snowfall in both Gunsan and Gangneung; the former is positively correlated while the latter is negatively correlated. This result might suggest that if the intensity of Siberian High would weakens due the ongoing global warming in the future, there would be a possibility that the amount snowfall could decrease in Gunsan but it could increase in Gangneung.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.23 no.3
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• pp.236-247
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• 2011

This study investigates sea level (SL) rise due to global warming in the Northwestern Pacific (NWP) and Seas around the Korean peninsula (KP) using outputs of IPCC AR4 climate models. Particularly, components of the SL rise induced by a local steric effect, which was not considered in most climate models, were computed using model-projected 3-dimensional temperature and salinity data. Analysis of the SL data shows that the ratio of the SL rise in the NWP and KP was about two times higher than that in global mean and particularly the ratio in the Kuroshio extension region was the highest. The SL rises over 100 years estimated from MPI_ECHAM5 and GFDL_CM2.1 model by A1B scenario considering the thermosteric effect were 24 cm and 28 cm for the NWP and 27 cm and 31 cm for the Seas around the KP, respectively. Statistical analysis reveals that these SL rises are caused by the weakening of the Siberian High in winter as well as variations of pressure system in the NWP and by the resultant change of water temperature. It also found that the highest SL rise in the Kuroshio extension region of the NWP was connected with the large increase of water temperature in this area.

• Journal of Power System Engineering
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• v.21 no.6
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• pp.110-116
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• 2017

Recently the global warming caused by greenhouse gas has emerged as a global environmental problem. For this reason the continued efforts to reduce greenhouse gas emission by international cooperation and each country are in progress. Climate changing has been recognized as the world economy development from fossil fuel use is the culprit. The international maritime organization marine environment protection committee of the global warming reduction emerged restrictions on air pollution have been strengthened. Therefore, the author has investigated the effects of fuel temperature on the characteristics of combustion and performance, using an four-cycle, six cylinders and direct injection diesel engine. The results of cylinder pressure, rate of pressure rise, rate of heat release and specific fuel consumption were increased by changing of fuel temperature.

• Proceedings of the KSME Conference
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• 2001.06a
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• pp.782-787
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• 2001

This paper is concerned with the global rupture of a nuclear reactor pressure vessel(RPV) in a severe accident. During the severe reactor accident of molten core, the temperature and the pressure in the nuclear reactor rise to a certain level depending on the initial and subsequent condition of a severe accident. While the rise of the temperature cause the thermal softening of RPV material, the rise of the internal pressure could cause failure of the RPV lower head. The global rupture of an RPV is simulated by finite element limit analysis for the collapse pressure and mode and this analysis results have been compared with a variation of the internal pressure of RPV. The finite element limit method is a systematic tool to secure the safety criteria of a nuclear reactor and to evaluate the in-vessel corium retention.

• Atmosphere
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• v.29 no.5
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• pp.585-597
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• 2019

This study evaluates the performance of Weather Research and Forecasting (WRF) model in simulating temperature over the COordinated Regional climate Downscaling EXperiment-East Asia (CORDEX-EA) Phase 2 domain for the reference period (1981~2005), and assesses the changes in temperature and its extremes in the mid-21st century (2026~2050) under global warming based on Representative Concentration Pathway (RCP) scenarios. MPI-ESM-LR forced by two RCP scenarios (RCP2.6 and RCP8.5) is used as initial and lateral boundary conditions. Overall, WRF can capture the observed features of temperature distribution reflecting local topographic characteristic, despite some disagreement between the observed and simulated patterns. Basically, WRF shows a systematic cold bias in daily mean, minimum and maximum temperature over the entire domain. According to the future projections, summer and winter mean temperatures over East Asia will significantly increase in the mid-21st century. The mean temperature rise is expected to be greater in winter than in summer. In accordance with these results, summer (winter) is projected to begin earlier (later) in the future compared to the historical period. Furthermore, a rise in extreme temperatures shows a tendency to be greater in the future. The averages of daily minimum and maximum temperatures above 90 percentiles are likely to be intensified in the high-latitude, while hot days and hot nights tend to be more frequent in the low-latitude in the mid-21st century. Especially, East Asia would be suffered from strong increases in nocturnal temperature under future global warming.

• Journal of the Korean Professional Engineers Association
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• v.43 no.1
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• pp.46-49
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• 2010

Sea temperature rise by global warming, depletion of fishery resources and ocean pollution have caused unusual population explosion of the jellyfish, The blooming of jellyfish have brought social problem and economic damage, Therefore the interdisciplinary study of jellyfish by scientists and countermeasure are needed.

• Journal of the Korean Society of Marine Environment & Safety
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• v.16 no.4
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• pp.421-425
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• 2010

It has been mown that the global warming has an effectet on marine ecosystem and marine environments. Then, fisherman's activity and fishing production were decreased by changing of marine plankton composition and increasing of harmful marine organisms such as jellyfish, starfish and green laver bloom. Harmful red tides algae bloom and the deserted sea bottom often occurred due to increasing of sea water temperature and sea level rising in Korea. In this report, the cause and mechanism of the global warming phenomenon and it's effect on marine environment and marine ecosystem were introduced, and measures against global warming were suggested

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.27 no.1
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• pp.56-62
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• 2015

The potential impact of water temperature on sea level and air temperature rise in response to recent global warming has been noticed. To predict the effect of temperature change on river water quality and aquatic environment, it is necessary to understand and predict the change of water temperature. Air-water temperature relationship was analyzed using air temperature data at Buan and water temperature data of Shinsi, Garyeok, Mangyeong and Dongjin. Maximum and minimum water temperature was predicted by neural network and the results show a very high correlation between measured and predicted water temperature.

• Korean Journal of Environmental Agriculture
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• v.41 no.4
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• pp.318-327
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• 2022

BACKGROUND: The mean annual temperature of the Korean Peninsula will continue to rise due to global warming. 'Shiranuhi' mandarin-a late-harvest cultivar-is primarily cultivated in plastic greenhouses where high temperatures cannot be directly avoided. Therefore, growth and fruit quality changes under elevated temperatures must be investigated. METHODS AND RESULTS: Elevated temperatures were divided into three groups [2℃ (T-I), 4℃ (T-II), and 6℃ (T-III) above the ambient temperature] during the 2019-2020 season. Mean temperatures were 17.1℃, 18.6℃, and 20.2℃ in T-I, T-II, and T-III, respectively. The bud bursts in T-II and T-III were earlier than that in T-I at 7 days and 11 days, respectibely. And the full blooms in T-II and T-III were earlier than that in T-I at 11 days and 23 days, respectively. Fruit size significantly increased with increased temperature. The citrus color index in the coloring phase markedly differed across treatments. Further, total soluble solid and acid contents markedly changed with temperature rise but the sugar-to-acid ratio did not. Sucrose content tended to decrease with increase in temperature, but citric acid content remained unaffected. CONCLUSION(S): Elevated temperature accelerated plant growth and development but delayed rind color development in 'Shiranuhi' mandarin. Therefore, rise in ambient temperature by >4.6℃ may negatively affect yield and fruit quality.

• Journal of Astronomy and Space Sciences
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• v.27 no.3
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• pp.231-238
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• 2010

We analyzed global positioning system (GPS)-derived precipitable water vapor (PWV) trends of the Korea Astronomy and Space Science Institute 5 stations (Seoul, Daejeon, Mokpo, Milyang, Sokcho) where Korea Meteorological Administration meteorological data can be obtained at the same place. In the least squares analysis, the GPS PWV time series showed consistent positive trends (0.11 mm/year) over South Korea from 2000 to 2009. The annual increase of GPS PWV was comparable with the 0.17 mm/year and 0.02 mm/year from the National Center for Atmospheric Research Earth Observing Laboratory and Atmospheric InfraRed Sounder, respectively. For seasonal analysis, the increasing tendency was found by 0.05 mm/year, 0.16 mm/year, 0.04 mm/year in spring (March-May), summer (June-August) and winter (December-February), respectively. However, a negative trend (-0.14 mm/year) was seen in autumn (September-November). We examined the relationship between GPS PWV and temperature which is the one of the climatic elements. Two elements trends increased during the same period and the correlation coefficient was about 0.8. Also, we found the temperature rise has increased more GPS PWV and observed a stronger positive trend in summer than in winter. This is characterized by hot humid summer and cold dry winter of Korea climate and depending on the amount of water vapor the air contains at a certain temperature. In addition, it is assumed that GPS PWV positive trend is caused by increasing amount of saturated water vapor due to temperature rise in the Korean Peninsula. In the future, we plan to verify GPS PWV effectiveness as a tool to monitor changes in precipitable water through cause analysis of seasonal trends and indepth/long-term comparative analysis between GPS PWV and other climatic elements.