• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.22 no.7
• /
• pp.436-441
• /
• 2010

The purpose of this study is to revise the HDD(Heating Degree-Days) of main cities of Korea because the outside temperature rise have been accelerated by global warming recently. Now our HDD(Heating Degree-Days) for the utility design of district heating system had been `established in 20 years ago. Therefore new heating degree days for main cities of korea had been required and determined using long-term measured outside weather temperature data during 30 years. For the analysis of HDD, five different base temperatures ranging from 24 to $16^{\circ}C$ were chosen in the calculation of heating degree days. And new yearly heating degree days of 15 cities of korea were given in the tabular form.

• Geomechanics and Engineering
• /
• v.32 no.5
• /
• pp.513-521
• /
• 2023

Temperature is one of the most critical elements that influence the rutting and fatigue resistance of flexible pavements. Particularly in extreme hot regions in Saudi Arabia, high temperature would significantly reduce the rutting resistance of flexible pavements leading to reduction of pavement service life. Due to the impacts of global warming, average temperature in Saudi Arabia is expected to further increase by about 4℃ by the end of the 21st century. The substantial increase in average temperature will elevate the expected pavement maintenance and rehabilitation cost. This paper analyzes the structural effects of temperature on pavement using layered elastic analysis based on finite element techniques. The research team calculated the potential loss of pavement service life due to the projected temperature increase and climate change. The paper also analyzed potential impact of using carbon waste in asphalt concrete to tackle the derogatory impacts of temperature rise.

• Proceedings of the SAREK Conference
• /
• 2008.06a
• /
• pp.943-948
• /
• 2008

Global average temperature rise accelerates by global warming in the three decades of the 20th century. But Current HDD ( Heating Degree-Days) which we are using has been established 20 years ago. Therefore new heating degree days for 15 district areas of korea was determined using long-term measured data. Five different base temperatures ranging from 24 to $16^{\circ}C$ were chosen in the calculation of heating degree days. And yearly heating degree days were given in the tabular form.

• Proceedings of the SAREK Conference
• /
• 2007.11a
• /
• pp.17-22
• /
• 2007

Global average temperature rise accelerates by global warming in the three decades of the 20th century. But now we use heating degree days which was established 20 years ago. Therefore new heating degree days for 15 district areas of korea was determined using long-term measured data. Five different base temperatures ranging from 24 to $16^{\circ}C$ were chosen in the calculation of heating degree days. And yearly heating degree days were given in the tabular form.

• Atmosphere
• /
• v.19 no.1
• /
• pp.53-66
• /
• 2009

The purpose of this study is to describe the roles of carbon dioxide in the climate change, and carbon dioxide reduction policies in some countries. In addition, ways to cope with climate change in Korea are also discussed. Currently, global temperatures are rising due to the carbon dioxide produced by human beings. Global temperatures will rise approximately $6^{\circ}C$ until 2100 if we emit carbon dioxide at a present rate. Temperature rise will affect the terrestrial and oceanic resources, and ultimately influence the socio-economic structures including political stability. Most of the carbon dioxide comes from fossil fuels. Therefore, it is urgent to reduce the use of energy, which comes from fossil fuels. Solving the climate change due to the increases in carbon dioxide is a global problem. Korea should participate in the international community and cooperate with each other in order to reduce the carbon dioxide concentration. No policy was announced for the reduction of carbon dioxide so far. Korea should make a policy for the reduction of carbon dioxide in a specific year compared to that of certain standard year such as 1990 or 2005. Making policy should be based on the scientific result of the amount of carbon dioxide emitted and absorbed. Germanwatch announced the Climate Change Performance Index (CCPI) in order to evaluate an effort to reduce the carbon dioxide for 56 countries which emits 90 % of global carbon dioxide. Ranking for Korea is 51 among 56 countries. This clearly indicates that the appropriate carbon dioxide reduction has not been exercised yet in Korea. Researchers have a moral responsibility to provide updated new ideas and knowledges regarding climate change. Politicians should have a sharp insight to judge the ideas provided by researchers. People need an ethics to reduce the carbon dioxide in every day's life. Scientific research should not be influenced by stress caused by external budget and negative impact of capitalism. Science should be based on the pure curiosity.

• Journal of the Korean Institute of Rural Architecture
• /
• v.19 no.4
• /
• pp.49-56
• /
• 2017

Each country in the world currently concentrates on shifting into clean energy, which can be alternative energy, for global environment protection and solution to the problem of fossil fuel depletion. The Korean government is predicted to develop renewable energy, such as solar power, ground power, and offshore wind power, and to increase their supply ratios by ending the use of coals and nuclear power plants. This study conducted experiments on thermal storage performance of Trombe wall thermal storage materials using solar power and simulations in order to offer baseline data for the development of a hybrid air circulation system for heating that can maximize efficiency by simultaneously using solar and geothermal power. The study results are as follows: (1) In all the specimens with 3m, 5m, and 7m in the length of thermal storage pipe, $5.7^{\circ}C$, $7.8^{\circ}C$, and $10.5^{\circ}C$ rose, respectively, as the thermal storage effect of the specimens attaching insulation film and black tape to the general funnel. They were most excellent in terms of thermal storage effect. (2) As a result of thermal performance evaluation on the II type specimens, II-3 ($7.8^{\circ}C$ rise) > II-4 ($5.3^{\circ}C$ rise) > II-1 ($3.9^{\circ}C$ rise) > II-2 ($2.3^{\circ}C$ rise) was revealed, and thus II-3 (insulation film + black tape) was most effective as shown in the I type. (3) This study analyzed air current and temperature distribution inside of the greenhouse by linking actually measured values and simulation interpretation results through the interpretation of CFD (computational fluid dynamics). As a result, the parts absorbing heat and discharging heat around the thermal storage pipe could be visibly classified, and temperature distribution inside of the greenhouse around the thermal storage pipe could be figured out.

• Journal of the Korean Society for Marine Environment & Energy
• /
• v.10 no.1
• /
• pp.59-65
• /
• 2007

Rapid variation of coastal ecosystem in the East Sea of Korea, such as fishery resource variation and subtropical chang of bentic flora, accordong to the global warming are actually noticed. In this study we try to identify the characterics of water mass existing in this coastal area and to consider the variation of their physical and chemical properties using data of temperature, salinity and dissolved oxygen obtained by National Fisheries Research & Development Institute from 1960 to 2005. The temperature of all water mass rise during last 45 years; the rise of North Korea Cold Water temperature (about $2.33^{\circ}C$) is 1.5 times higher than that of Tsushima warm water (about $1.6^{\circ}C$), and the temperature rise of Tsushima Surface Water, directly affected by climate chang is $2.57^{\circ}C$, higher than the atmospheric temperature rise during same period, indicating that subtropical change makes progress more rapidly in the coastal marine ecosystem than in the land ecosystem. Otherwise, the salinity in the surface water decrease $0.29\%_{\circ}$ during last 45 years due to the rising trend of rainfall with atmospheric temperature. The dissolved oxygen concentration in the all water mass make a decreasing trend. Specially for the North Korea Cold Water, the dissolved oxygen concentration diminish 0.021 mg/l per year and the decrease in the East Sea Proper Water indicate a change of inner water circulation system.

• Journal of Environmental Science International
• /
• v.23 no.11
• /
• pp.1863-1879
• /
• 2014

This study aims at classifying and interpreting on the shrine forest vegetation located in Jirisan national park affiliated to an ecotone in southern part of Korea, foreseeing a vegetation change based on composition species and dominant species on canopy, and proposing the direction of vegetation management. The shrine forests were classified into the 7 community units as Chamaecyparis obtusa-Cryptomeria japonica afforestation, Pinus densiflora community, Pinus rigida afforestation, Quercus variabilis-Quercus serrata community, Zelkova serrata-Kerria japonica for. japonica community, Phyllostachys bambusoides forest, Camellia japonica community. This research is also expatiated on the analogous results of ordination analysis with phytosociological analysis. The constituents of deciduous broad-leaved forest in the warm temperate zone were appeared in the most vegetations. It emerged less that the constituents of evergreen broad-leaved forest in the warm-temperate zone and deciduous broad-leaved forest in the cold-temperature zone. The life form analyses were made use with the two ways: appearance species in total communities and each community. The species diversity of shrine forests is declined because the high dominances of Sasa borealis and Pseudosasa japonica emerged in the shrub and herb layers. These shrine forests will be succession to Q. variabilis-Q. serrata community as the representative vegetation of deciduous broad-leaved forest in the warm-temperate zone, owing to the temperature rise by global warming, and an evergreen broad-leaved forest will be able to be also formed if a temperate rise will be continued. The one of the artificial management of shrine forests is to consider the introduction of the constituents of evergreen broad-leaved forest in the warm-temperate zone.

• Atmosphere
• /
• v.28 no.4
• /
• pp.393-402
• /
• 2018

This study investigated future changes in the Arctic permafrost features and related biogeochemical alterations under global warming. The Community Land Model (CLM) with biogeochemistry (BGC) was run for the period 2005 to 2099 with projected future climate based on the Special Report on Emissions Scenarios (SRES) A2 scenario. Under global warming, over the Arctic land except for the permafrost region, the rise in soil temperature led to an increase in soil liquid and decrease in soil ice. Also, the Arctic ground obtained carbon dioxide from the atmosphere due to the increase in photosynthesis of vegetation. On the other hand, over the permafrost region, the microbial respiration was increased due to thawing permafrost, resulting in increased carbon dioxide emissions. Methane emissions associated with total water storage have increased over most of Arctic land, especially in the permafrost region. Methane releases were predicted to be greatly increased especially near the rivers and lakes associated with an increased chance of flooding. In conclusion, at the end of $21^{st}$ century, except for permafrost region, the Arctic ground is projected to be the sink of carbon dioxide, and only permafrost region the source of carbon dioxide. This study suggests that thawing permafrost can further to accelerate global warming significantly.

• Journal of Environmental Science International
• /
• v.25 no.2
• /
• pp.295-310
• /
• 2016

In this study, changes in daily temperature range were investigated using daily maximum and minimum temperatures of Busan and Daegu for last 81 years (1934-2014), and also characteristics of daily temperature range and seasonal fluctuations by urbanization were examined. First, elapsing changes showed a lower decreasing trend in Busan ($0.32^{\circ}C$) than Daegu ($1.28^{\circ}C$) for last 81 years. Daily temperature range showed the highest rise in winter in both Busan and Daegu. Second, daily temperature range due to urbanization showed that Busan had a pronounced decreasing trend before urbanization meanwhile Daegu showed the same trend after urbanization. On seasonal changes, the results of Busan showed a decreasing trend in summer before urbanization, and in autumn after urbanization. For Daegu, the results showed a decreasing trend in spring before urbanization, and in winter after urbanization. Seasonal fluctuations of Busan showed little difference in the pre and post-urbanization, except in winter and summer. There was large difference in daily temperature range in winter after urbanization, and in summer before the urbanization. The results in Daegu showed that there was decreasing trend of daily temperature range in all seasons after urbanization.