• Journal of Korean Society of Forest Science
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• v.105 no.4
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• pp.510-516
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• 2016

This study was conducted to investigate the physiological responses of newly-germinated seedlings of Fraxinus rhynchophylla Hance, Zelkova serrata (Thunb.) Makino, Betula costata Trautv. and Quercus variabilis Blume to open-field experimental warming. The seedlings in the warmed plots were warmed with $2.7^{\circ}C$ higher air temperature than those in the control plots using infrared heaters since April, 2015. Physiological responses (stomatal conductance, transpiration rate, chlorophyll content and net photosynthetic rate) to experimental warming varied with the species and the time of the measurement. Stomatal conductance ($mmol{\cdot}m^{-2}{\cdot}s^{-1}$) tended to decrease for F. rhynchophylla (Control: $158.97{\pm}42.76$; Warmed: $42.07{\pm}8.24$), Z. serrata (Control: $170.53{\pm}27.22$; Warmed: $101.17{\pm}42.27$) and B. costata (Control: $249.93{\pm}47.39$; Warmed: $150.73{\pm}26.52$). Transpiration rate ($mmol{\cdot}m^{-2}{\cdot}s^{-1}$) also decreased for F. rhynchophylla (Control: $4.08{\pm}0.62$; Warmed: $1.74{\pm}0.39$), Z. serrata (Control: $4.32{\pm}0.44$; Warmed: $3.24{\pm}1.14$) and B. costata (Control: $6.21{\pm}0.38$; Warmed: $4.66{\pm}0.28$). However, warming exhibited only minimal effects on stomatal conductance and transpiration rate of Q. variabilis seedlings. Chlorophyll content increased by the warming treatment while the effect of warming was not significant on net photosynthetic rate, since the warming treatment had a weak influence for changing net photosynthetic rate.

• Journal of Agricultural Extension & Community Development
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• v.11 no.2
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• pp.291-301
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• 2004

As Russian government signs the Kyoto Protocol on November 2004, it will go into effect on Feb. 16 2004. Under the Protocol, 38 industrialized countries are to reduce their combined emissions of six major greenhouse gases, including carbon dioxide and methane, to below 1990 levels during the 2008-2012 period. Korea ratified the Protocol in 2002 and is currently exempt from the reduction measures. It is expected, however, that Korea will be pressured to join the reduction scheme from 2013. Although the Kyoto Protocol is national-level agreement each country's urban governments are expected and have to play important role to make it successful one. It is more so for such mesa cities as Seoul which has experienced rapidly worsening environment recent years. Statistics shows that the annual average temperature in Seoul has increased by $1.5^{\circ}C$ for the last century, which is much higher than the national average. 'Heat Island' effect is not unusual any more in Seoul. This study reviews the key points of the Kyoto Protocol, urban warming phenomena in Seoul and its policy responses. In doing so, this study evaluates Tokyo case as a comparative one. It is found that Seoul needs to develop more concrete and feasible policy measures to get current efforts more effective.

• Atmosphere
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• v.17 no.2
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• pp.185-193
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• 2007

This study investigates urbanization effect in warming trend of surface air temperature over Korea. The data used in this study consist of the daily minimum and maximum temperatures during the period of 32 years(1968-1999) from 16 stations of KMA. To calculate magnitude and trend of urbanization effect, stations were classified into urban and rural stations using population statistics. Urban stations were defined as those with population densities greater than 1000 persons per kilometer squared in 1995. The others were defined as rural stations. The urban stations were also subdivided into two groups according to their population totals. For estimates of urban effect magnitude, temperature change was calculated by comparing 16-year mean values between 1968-83 and 1984-99. Then, the difference between each urban station and every rural station was calculated. During the analysis period of 32 years, maximum temperature increase is $1.22^{\circ}C$. In the total temperature increase, urban effect is estimated by 28.7%. For minimum temperature, it becomes larger by about 10% than that in maximum temperature. Therefore, urban effect in an increasing trend of minimum temperature is 38.9% in the change of $1.13^{\circ}C$.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.2221-2225
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• 2003

As a result of using a heat generator to experiment the physiological influence of the human body due to the warming effect of far-infrared radiation (FIR), the blood pressure of the subjects lowered and stabilized due the expansion of capillary vessels and salt discharge during perspiration as the temperature of the generator elevated($30{\sim}65^{\circ}C$). In case of heart rate, it decreased and stabilized when the temperature of the ‘far-infrared radiation heat generator’ was at a low temperature below $40^{\circ}C$. At a high temperature above $44^{\circ}C$, there was a slow elevation in the heart rate. However, the elevation of the heart rate is not a sudden elevation, therefore, does not give much stress to the heart.

• Korean Journal of Agricultural Science
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• v.38 no.2
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• pp.219-225
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• 2011

Changes in biota, species distribution range shift and catastrophic climate influence due to recent global warming have been observed during the last century. Since global warming affects various sectors, such as agriculture and vegetation, it is important to predict more accurate impact of future climate change. The purpose of this study is to examine the observed distribution of Abeliophyllum distichum in the Korean peninsula. For this purpose, two period (present and future) climate data were used. Mean data between 1950 and 2000, were used as the present value and the year 2050 and 2080 data from A1B senario in IPCC SRES were used for the future value. Potential habitation is analyzed by MaxEnt(Maximum Entropy model), and Abeliophyllum distichum's coordinates data were used as a dependent variable and independent variables are composed of environmental data such as BioClim, altitude, aspect and slope. The result of six types GCM mean calculation, the potential habitability decreased by 40-60% of the average existing distribution. The methodogies and results of this research can be applicable to the climate changing adaptation stratiegies for the biodiversity conservation.

• Proceedings of the Korean Quaternary Association Conference
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• 2004.06a
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• pp.29-29
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• 2004

Long term observational analysis by climatologists has confirmedthat the global warming is no longer a topic of debate among scientists andpolicy makers. According to the report of IPCC-2001 (Intergovernmental Panelon Climate Change), the global mean surface air temperature is increasinggradually. The reported increase of mean temperature is by 0.6 degree in the end of twentieth century. This could represent severe threat for propertylosses especially due to increase in the number of extreme weather arising out of global warming. period of model integration from 2001 to 2100 using output of ECHAM4/HOPE-G of Max Planet Institute of Meteorology (MPI) for IPCC SRES (Special Report on Emission Scenarios). The main results of this study indicate increase of surface air temperature by 6.20C and precipitation by 2.6% over Korea in the end of 21st century. Simulation results also show that there is increase in daily maximum and minimum temperatures while decrease in diurnal temperature range (DTR). DTR changes are diminished mainly due to relatively rapid increase of daily minimum temperature than that of daily maximumtemperature. It has been observed that increase in precipitation amount anddecrease in the number of rainy days lead to increase of pre precipitationintensity.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.13 no.2
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• pp.16-21
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• 2017

In this study, the flow effect of warming and cooling in the air supply of a pit for air conditioning were evaluated in BS art museum. We simulated the flow temperature for a pit winter and summer seasons using computational fluid dynamics. Consequential, energy saving, energy saving costs and initial payback periods were calculated and the following conclusions were drawn. The warming effect of the winter increased by $18.1^{\circ}C$ and $0.2^{\circ}C/m$ and the cooling effect of the summer decreased by $6.1^{\circ}C$ and dropped to $0.07^{\circ}C/m$. Energy saving appeared to be 19.1 kW in the summer and 54.3 kW in winter. Energy saving costs ranged from 2,567,119 won/year to 5,134,238 won/year and at minimum, initial payback period for initial investment was 3.9 years. As a result, the air supply system using an existing pit without any burden on initial investment costs is believed to contribute to energy saving through warming and cooling of unutilized energy effects.

• Journal of the Korean earth science society
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• v.39 no.4
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• pp.327-341
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• 2018

Extreme temperatures and precipitations are expected to be more frequently occurring due to the ongoing global warming over the Korean Peninsula. However, few studies have analyzed the synoptic weather patterns associated with extreme events in a warming world. Here, the atmospheric patterns related to future extreme events are first analyzed using the HadGEM3-RA regional climate model. Simulations showed that the variability of temperature and precipitation will increase in the future (2051-2100) compared to the present (1981-2005), accompanying the more frequent occurrence of extreme events. Warm advection from East China and lower latitudes, a stagnant anticyclone, and local foehn wind are responsible for the extreme temperature (daily T>$38^{\circ}C$) episodes in Korea. The extreme precipitation cases (>$500mm\;day^{-1}$) were mainly caused by mid-latitude cyclones approaching the Korean Peninsula, along with the enhanced Changma front by supplying water vapor into the East China Sea. These future synoptic-scale features are similar to those of present extreme events. Therefore, our results suggest that, in order to accurately understand future extreme events, we should consider not only the effects of anthropogenic greenhouse gases or aerosol increases, but also small-scale topographic conditions and the internal variations of climate systems.

• Journal of Bio-Environment Control
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• v.8 no.1
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• pp.1-8
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• 1999

This study was carried out to estimate the warmed water irrigation and the warmed soil efficiency on protected cultivation of cucumber in winter season. The water of 28$^{\circ}C$ was continuously supplied for soil warming and that is $25^{\circ}C$ for warmed water irrigation. Cucumber growth was analyzed when tile soil kept up the optimum temperature in the root zone. The cucumber growth are compared with the warmed soil plots. isolated warmed soil plots and non-warmed soil plots. The cucumber growth in warmed soil plots and isolated warmed soil plots were 20~50% higher than non-warmed soil plots compare to that by the warmed irrigation. In the non-warmed soil plots, the stem diameter and the number of leaves in the warmed water irrigation plots are 10% higher than those in the normal water irrigation plots. The yields in isolated warmed soil plots were 37~38% higher than non-warmed soil plots and those in warmed soil plots were 85~96% higher than non-warmed soil plots. The fruit length, weight and diameter in warmed soil plots were 15% higher than those in the non-warmed plots.

• Journal of Korean Elementary Science Education
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• v.34 no.1
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• pp.15-31
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• 2015

The purpose of this study was to investigate elementary student teachers' conceptions about the mechanism of the greenhouse effect, the greenhouse gases, the global warming, and their learning experiences of the greenhouse effect and the global warming. Participants were 82 student teachers in their second year of studies (science education: n=28, not science education: n=27) and in their fourth year of studies (science education: n=27). The open-ended questionnaire was used to examine the teachers' spontaneous ideas depicted by their drawings and/or writings. The results of this study are as follows: First, the student teachers' scientific response rate about key concepts related to the mechanism of the greenhouse effect was low (6.1%~28.0%); Second, although there are various greenhouse gases, it was only carbon dioxide that the student teacher's response rate was more than 80%; Third, only 17.1% of the student teachers clearly distinguished the greenhouse effect and the global warming; Fourth, there was a tendency that the student teacher group in the fourth year of studies and science education showed higher scientific response rate about the concepts than the other two groups.