• Title/Summary/Keyword: Surface temperature change

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Projected Climate Change Impact on Surface Water Temperature in Korea (기후변화에 따른 지표수의 수온 영향평가)

  • Ahn, Jong Ho;Han, Dae Ho
    • Journal of Korean Society on Water Environment
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    • v.26 no.1
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    • pp.133-139
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    • 2010
  • Global human activities associated with the use of fossil fuels have aggravated climate change, increasing air temperature. Consequently, climate change has the potential to alter surface water temperature with significant impacts on biogeochemical cycling and ecosystems in natural water body. In this study, we examined temporal trends on historical records of surface water temperature, and investigated the air temperature/water temperature relationship and the potential water temperature change from an air temperature scenario developed with regional climate model. Although the temporal trends of water temperature are highly variable site-by-site, surface water temperature was highly dependent on air temperature, and has increased significantly in some sub-watersheds over the last two decades. The results presented here demonstrate that water temperature changes are expected to be slightly higher in river system than reservoir systems and more significant during winter than summer for both river and reservoir system. Projected change of surface water temperature will likely increase $1.06^{\circ}C$ for rivers and $0.95^{\circ}C$ for reservoirs during the period 2008 to 2050. Given the potential climatic changes, every $1^{\circ}C$ increase in water temperature could cause dissolved oxygen levels to fall every 0.206 ppm.

Change of Surface Temperature in Woodceramics Made from MDF(I) -Effect of Density and Burning Temperature- (MDF로 제조된 우드세라믹의 표면온도변화(I) -밀도 및 소성온도의 영향-)

  • 오승원
    • Journal of Korea Foresty Energy
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    • v.21 no.1
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    • pp.1-6
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    • 2002
  • The following conclusions were obtained with measuring the surface temperature change of woodceramics which were made of MDF to identify usability of using them as a sub-material for heating system when installing Ondol heating floor. For this purpose, woodceramics were burned at the temperature of $650^{\circ}C$ and $800^{\circ}C$ 1. Surface temperature of woodceramics increased with the increase of density of woodceramics, but no significant difference was detected at the surface temperature when burning temperature was changed. 2. Surface temperature change under given temperature increased as time passed and it showed more increase in temperature at the burning temperature of 80$0^{\circ}C$. 3. Surface temperature change with the change in floor temperature increased u hen floor temperature increased and heating mechanism was fast with increase of measuring temperature.

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Change of Surface Temperature in Woodceramics Made from MDF(II) - Effect of Impregnation Rate and Burning Temperature - (MDF로 제조된 우드세라믹의 표면온도 변화(II) - 수지 함침율과 소성온도의 영향 -)

  • Oh, Seung Won;Byeon, Hee Seop
    • Journal of the Korean Wood Science and Technology
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    • v.31 no.1
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    • pp.41-45
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    • 2003
  • In this study, woodceramics were made from MDF with various resin impregnation rate. To investigate the change of surface temperature of woodceramics, the impregnated MDF was burned at the temp. 600, 800, 1,000, 1,200℃. Surface temperature of woodceramics was increased as impregnation rate and burning temperature was increased. The specimen burned at 800℃ was lower than others. Change of temperature under given temperature increased as time passed and it showed more increased in temperature at burning temperature of 1,200℃. Change of surface temperature increased when floor temperature increased and the temperature was 49.2℃ at 70℃ in floor temperature of 1,200℃ specimen. The decent in surface temperature of woodceramics was the fastest decrease at the burning temperature of 800℃ specimen.

On response of Surface Equilibrium Temperature for Change of Surface Characteristics : An EBM Study (지표 특성 변화에 대한 평형온도의 반응 연구 : EBM 연구)

  • Seo, Ye-Won;Chu, Jung-Eun;Ha, Kyung-Ja
    • The Korean Journal of Quaternary Research
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    • v.24 no.2
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    • pp.1-11
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    • 2010
  • Energy Balance Model (EBM) was used to experiment the distribution of surface equilibrium temperature which responds to external forcing associated with the surface characteristics. Surface equilibrium temperature is calculated as sum of incoming solar radiation and latitudinal transport is balanced with outgoing infrared radiation. To treat incoming solar radiation, the source of the earth energy, significantly for energy balance, the experiment for surface equilibrium temperature distribution was performed considering the energy balance with the latitudinal albedo change as well as land and sea distribution. In addition, linear albedo change experiment, arctic albedo 5%, 10%, 15% change experiments and the opposite albedo change experiments between arctic and mid-latitudes were performed using incoming solar radiation as an external forcing. Moreover, with and without ice-albedo feedback experiments were performed. Increasing of arctic albedo is blocked out the incoming solar radiation so that it induces decreasing of latitudinal heat transport. It is strengthened energy transport from low latitudes by keeping arctic low energy states. Therefore the temperature change in the mid-latitudes exhibits larger response than that of arctic due to the difference of transport. The land which has lower heat capacity than sea can be reach to equilibrium temperature shortly. Also land is more sensitive to temperature change with respects to albedo. Thus it induces the thermal difference between land and sea. As a result, the equilibrium temperature exhibits differently as the difference of albedo and heat capacity which are the one of surface characteristics. Surface equilibrium temperature decreases as albedo increase and the ratio of temperature change is large as heat capacity is small. The decreasing of surface equilibrium temperature with respects to increasing of linear albedo is accelerated by ice-albedo feedback. However local change of surface equilibrium temperature decreases non-linearly.

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On the crack behaviour of the downstream surface of the concrete gravity dam by atmosphere temperature change (대기온도의 변화에 의한 콘크리트 중력댐 하류면의 균열거동에 관한 연구)

  • 김조수;장희석;정태환
    • Proceedings of the Korea Concrete Institute Conference
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    • 1999.10a
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    • pp.643-646
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    • 1999
  • Downstream surface of the concrete gravity dam receives thermal stress due to atmosphere temperature change. So in this paper, the behaviors of crack located in the downstream surface were investigated, when considering the temperature change.

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A Study at Investigating the Climate Change in East Asia with Changing Sea Surface Temperature

  • Park, Geun-Yeong;Lim, Yong-Jae
    • Journal of Integrative Natural Science
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    • v.13 no.1
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    • pp.27-33
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    • 2020
  • The unsustainable human activities like increased use of automobiles, heavy industrialization and the use of large volumes of fertilizers, chemicals and pesticides in the agricultural land cause climate change problems in one way or another. Under normal circumstances, the heat radiations from the sun will be reflected back. An excessive volume of GHGs in the atmosphere would prevent these radiations from reflecting back. East Asia is facing severe climate change issues in recent times. A lot of climate change problems such as hurricanes and floods have been reported from this region in the last couple of decades. The study aimed at investigating the climate change in East Asia with changing Sea Surface Temperature (SST). The study adopted a quantitative research method with a case study research design where a deliberate focus was made on the East Asia Region. Secondary data was gathered and analyzed to yield both descriptive and inferential statistics. The study concluded that the impact of East Asia Climate variability was significant mainly for some extreme events. Also, the study concluded that there was a significant link between the change of the East Asia climate variability and that of the sea surface temperature. Further, the study concluded that a linear relationship existed between the sea surface temperature and the climate of East Asia. Hence, a linear regression was a significant predictor of the East Asia Climate (EAC) based on changing sea surface temperature. The model revealed that 37.4% of the variations in the climate change index were explained by the changes in the sea surface temperature. The climate was expected to change with a value of 49.48 for a unit change in the sea surface temperature.

Detection of Urban Expansion and Surface Temperature Change using Landsat Satellite Imagery (Landsat 위성영상을 이용한 도시확장 및 지표온도 변화 탐지)

  • Song, Yeong-Sun
    • Journal of Korean Society for Geospatial Information Science
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    • v.13 no.4 s.34
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    • pp.59-65
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    • 2005
  • It is very important to detect land cover/land use change from the past and to use it for future urban plan. This paper investigated the application of Landsat satellite imagery for detecting urban growth and assessing its impact on surface temperature in the region. Land cover/land use change detection was carried out by using 30m resolution Landsat satellite images and hierarchial approach was introduced to detect more detail change on the changing area through high resolution aerial photos. Also, surface temperature according to land cover/land use was calculated from Landsat TM thermal infrared data and compared with real temperature to analyze the relationship between urban expansion and surface temperature. As a result, the urban expansion has raised surface radiant temperature in the urbanized area. The method using remote sensing data based on GIS was found to be effective in monitoring and analysing urban growth and in evaluating urbanization impact on surface temperature.

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The Land Surface Temperature Analysis of Seoul city using Satellite Image (위성영상을 통한 서울시 지표온도 분석)

  • Jeong, Jong-Chul
    • Journal of Environmental Impact Assessment
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    • v.22 no.1
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    • pp.19-26
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    • 2013
  • The propose of this study is to analyze the optimum spatial resolution of the urban spatial thermal environment structure and to evaluate of the possibility detection using aerial photographs and thermal satellite images. The proper techniques of the optimum spatial resolution for the urban spatial thermal environment structure were analyzed. Thermal infrared satellite image of Seoul city were used for the change rate of surface temperature variation and suggested to the spatial extent and effects of urban surface characteristics and spatial data was interpreted as regions. To extract the surface temperature, Landsat thermal infrared satellite image compared with an automatic weather station data and in the field of the measured temperature and surface temperature by thermal environment affects, the spatial domain has been verified. The surface temperature of the satellite images to extract after adjusting surface temperature isotherms were constructed. The changes in surface temperature from 2008 to 2012 the average surface temperature observation images of changing areas were divided into space. The results of this study are as follows: Through analysis of satellite imagery, Seoul city surface temperature change due to extraction comfort indices were classified into four grades. The comfort index indicative of the temperature of Gangnam-gu, $23.7{\sim}27.2(^{\circ}C)$ range and Songpagu, a $22.7{\sim}30.6(^{\circ}C)$ respectively, the surface temperature of Yeouido $25.8{\sim}32.6(^{\circ}C)$ were in the range.

Change in Surface Temperature of Woodceramics Manufactured by Sawdust Boards - Effect of the Rate of Resin Impregnation and Burning Temperature - (톱밥보드로 제조된 우드세라믹의 표면온도 변화 - 수지 함침율과 소성온도의 영향 -)

  • 오승원;박금희;변희섭
    • Journal of Korea Foresty Energy
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    • v.22 no.1
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    • pp.24-29
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    • 2003
  • Using woodceramics made from sawdust board of Larix leptolepis thinning logs, change in surface temperature were investigated, by the rate of resin impregnation and burning temperature. As the surface temperature of silicon rubber heater was going up, that of woodceramics also increase rapidly. Woodceramics made from under the condition of the rate of resin impregnation 70-80% and burning temperature 800-$1000^{\circ}C$, were higher than that of surface temperature. Also, it was found that woodceramics maintained heat for a long time because the descending velocity of their surface temperature was lower than that of the heater.

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Change of Temperature using the Twentieth Century Reanalysis Data (20CR) on Antarctica (20세기 재분석 자료(20CR)를 이용한 남극대륙의 기온 변화)

  • Zo, Il-Sung;Jee, Joon-Bum;Lee, Kyu-Tae;Chae, Na-My;Yoon, Young-Jun
    • Ocean and Polar Research
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    • v.34 no.1
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    • pp.73-83
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    • 2012
  • Antarctica is very sensitive to climate change but the number of stations is not sufficient to accurately analyze climate change in this regoin. Model reanalysis data supplements the lack of observation and can be used as long term data to verify climate change. In this study, the 20CR (Twentieth Century Reanalysis) Project data from NCEP/NCAR and monthly mean data (temperature, solar radiation and longwave radiation) from 1871 to 2008, was used to analyze the temperature trend and change in radiation. The 20CR data was used to validate the observation data from Antarctica since 1950 and the correlation coefficients between these data were determined to be over 0.95 at all stations. The temperature increased by approximately $0.23^{\circ}C$/decade during the study period and over $0.20^{\circ}C$/decade over all of the months. This increasing trend was observed throughout the Antarctica and a slight increase was observed in the Antarctic Peninsula. In addition, solar radiation (surface) and longwave radiation (surface and top of atmosphere) trends correlated with the increase in temperature. As a result, outgoing longwave radiation at the surface is attenuated by atmospheric water vapor or clouds and radiation at the top of the atmosphere was reduced. In addition, the absorbed energy in the atmosphere increases the temperature of the atmosphere and surface, and then the heated surface emits more longwave radiation. Eventually these processes are repeated in a positive feedback loop, which results in a continuous rise in temperature.