• Title/Summary/Keyword: weather variation

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The annual variation pattern and regional division of weather eatropy in South Korea (남한의 일기엔트로피의 연변화유형과 지역구분)

  • ;Park, Hyun-Wook
    • Journal of the Korean Geographical Society
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    • v.30 no.3
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    • pp.207-229
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    • 1995
  • The characteristics of weather and climate in South Korea has great influences on the annual variation pattern and the appearance of the prevailing weather. The purpose of this paper is to induce the quantity of the weather entropy and annual variation pattern using the information theory and the principal component analysis. And author tried to classify the region according to the variation of its space scale, The raw materials used for this study are the daily cloudiness and precipitation during the years 1990-1994 at 69 stations in South Korea. It is divided into four classes of fine, clear, cloudy and rainy. The rcsults of this study can be summarized as follows: 1. Thc characteristics of annual variation pattern of weather entropy can be chiefly divided into five categories and the accumulated contributory rate of these is 73.1%. 2. Annual variation pattern of the first principal component reaches smaller in May, April and September than national average, and becomes greater when the winter comes. This weather entropy's quantity(Rs1) is positive in most area to the western sife of Soback Mountains and negative in most seaside area to the eastern side of Soback Mountains. 3. The characteristics of annual variation pattern of the second principal component shows that the entropy is more smaller in summer than national average and the rest of seasons shows larger, especially in January, May and September. This weather entropy's quantity(Rs2) is positive in most Honam Inland area to the western side of Soback Mountains and negative in most Youngnam Inland area to the eastern side of Soback Mountains. 4. Eight type regions (S1-S11) are classified based on the occurrences of minimum weather entropy in South Korea, and annual variation pattern of weather entropy by principal component analysis may be classified into sixteen type regions (Rs1-Rs9). Putting these things together, South Korea can be classifieed into thirty one type regions (Rs1S7-Rs9S10).

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The Weather Representativeness in Changma Period Established by the Weather Entropy and Information Ratio - Focused on Seoul, Taegu, Gwangju, Chungju, Puyo - (일기엔트로피 및 정보비에 의한 장마기의 일기대표성 설정 - 서울, 대구, 광주, 충주, 부여를 중심으로 -)

  • 박현욱;문병채
    • Journal of Environmental Science International
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    • v.12 no.4
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    • pp.399-417
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    • 2003
  • The seasonal variation and frequency of rainfalls of Korea peninsula in Changma period show strong local weather phenomenon because of it's topographical and geographical factors in Northeast side of Asia. Based on weather entropy(statistical parameter)-the amount of average weather information-and information ratio, we can define each area's weather representativeness, which can show us more constant form included topographical and geographical factors and seasonal variation. The data used for this study are the daily precipitation and cloudiness during the recent ten years(1990-1999) at the 73 stations in Korea. To synthesize weather Entropy, information ratio of decaying tendency and half$.$decay distance, Seoul's weather representativeness has the smallest in Summer Changma period. And Puyo has the largest value in September.

Variation Characteristics of Hourly Atmospheric Temperature Throughout a Winter (동계 시각별 외기온의 변동 특성에 관한 연구)

  • Lee, Seung-Eon;Shon, Jang-Yeul
    • Solar Energy
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    • v.12 no.2
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    • pp.1-8
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    • 1992
  • Identifying characteristics of heating and cooling systems requires estimation of thermal load of specific time interval, especially in cases that its system is operated intermittently, by using thermal storage, of in a partial load condition. Estimating the thermal load, however, needs to forecast hourly weather data variation. Hence, this paper attempts to examine characteristics of hourly ourdoor temperature variation as a preliminary research for the mathematical modeling of the hourly weather variation. Speculating characteristics of daily minimum and maximum temperature occurances, hourly outdoor temperature variation, and daily temperature differences in the increasing range ($07h{\sim}15h$) and decreasing range($15h{\sim}07h$), we were able to analyze changing patterns of daily temperature differences in each range in terms of daily solar amount, cloud ratio, and other weather data. Results from the multiple regression analysis enables us to conclude that daily differences in the increasing range are strongly affected last night temperature itself while the other range's differences are influenced by many weather data, which are solar amount, the variation of cloud, and the maximum temperature of the previous day.

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Characteristic of Cold-Weather Concrete by the Variation of Compressive Strength (강도 변화에 따른 한중콘크리트 특성연구)

  • 신성우;김인기;안종문
    • Proceedings of the Korea Concrete Institute Conference
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    • 1995.04a
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    • pp.154-159
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    • 1995
  • Cold weather concrete presents the many characteristic variation of quality, according to the mixing and cooling point, the cooling time and the quantity of air besides the compressive strength of concrete. Thus, in this study to verify the character of cold-weather concrete we make the concrete specimens at laboratory and cool them at cooling-melting machine and then test the 7days compressive strength of them, with the variation of compressive strength of concrete, cooling point, cooling time, cooling weather and air quantity. At the results, the compressive strength of concrete decrease in the case of early cooling point, long cooling time, low cooling temperature and the low design compressive strength

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Variation of the Period of Hot Weather Concrete with Elapse of Age in Korea (경년변화에 따른 우리나라 서중 콘크리트 적용기간의 변천)

  • Choi, Sung-Yong;Hong, Seak-Min;Lee, Chung-Sub;Jin, Cheng-Ri;Han, Min-Cheol;Han, Cheon-Goo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2008.11a
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    • pp.53-56
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    • 2008
  • This paper is to investigate the change of the period of hot weather concrete with elapse of age based on climate data. Climate data for 30 years and 5 years are used respectively. Determination of the period of hot weather concreting on architectural execution in Korea according to the specifications of AIJ, KSCE, and ACI are discussed. According to the research, the period of hot weather concreting with each specification in most regions lasts over 35 days. Compared with the period of cold weather concreting in hillside and inland area, coastal areas have shorter period in the same latitude. The period of hot weather concreting tends to decrease with high latitude. As expected, with the elapse of age, the period of hot weather concrete exhibited to decrease, especially, big city like Seoul, Busan etc had remarkably increased period by as much as a week. This is due to the global warming and industrialization effect with the elapse of age.

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Longitudinal Study on the Usage of Weather Information (기상정보의 활용에 관한 종관적 연구)

  • 김광명
    • Journal of Korean Elementary Science Education
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    • v.17 no.2
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    • pp.123-136
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    • 1998
  • In this study, it was purposed to investigate that the student's understading and usage of weather information for the students of elementary, middle and high school The questionaire of 20 questions of 5 categories which included how to get weather information, the understanding of reason for variation of weather elements, the abilities of reading weather map, understanding of weather forecast and the necessity and usefulness of weather map and clouds pictures of weather satellite were prepared and 2 classes of elementary school 5th grade each one class of 2nd and 3rd grade of middle school and 2 classes of high school were tested. followings were revealed in this study; 1) Students of all school are fond of TV watching to get weather information as they used to. 2) They think air temperatures is the most important weather elements and then rainfall. 5ut they seems to unknown the reason why weather elements are vary. 3) They seems to have poor ability of reading weather symbols in weather map and the distribution of air pressure systems. 4) They can read and understand about the reports of words on weather forecast, but most of them can't make weather forecast by the reading of weather map. 5) More than half of students think that the weather map is helpful and especially the cloud pictures from weather satellite is useful for usage of weather information.

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Competition between ICME and crustal magnetic field on the loss of Mars atmosphere

  • Hwang, Junga;Jo, Gyeongbok;Kim, Roksoon;Jang, Soojeong;Cho, Kyungsuk;Lee, Jaejin;Yi, Yu
    • The Bulletin of The Korean Astronomical Society
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    • v.42 no.2
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    • pp.62.3-63
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    • 2017
  • The Mars Atmosphere and Volatile (MAVEN) mission has been providing valuable information on the atmospheric loss of Mars since its launch in November 2013. The Neutral Gass and Ion Mass Spectrometer (NGIMS) onboard MAVEN, was developed to analyze the composition of the Martian upper atmospheric neutrals and ions depending on various space weather conditions. We investigate a variation of upper atmospheric ion densities depending on the interplanetary coronal mass ejections (ICMEs). It is known that the Mars has a very weak global magnetic field, so upper atmosphere of Mars has been strongly affected by the solar activities. Meanwhile, a strong crustal magnetic field exists on local surfaces, so they also have a compensating effect on the upper atmospheric loss outside the Mars. The weak crustal field has an influence up to 200km altitude, but on a strong field region, especially east longitude of $180^{\circ}$ and latitude of $-50^{\circ}$, they have an influence over 1,400km altitude. In this paper, we investigated which is more dominant between the crustal field effect and the ICME effect to the atmospheric loss. At 400km altitude, the ion density over the strong crustal field region did not show a significant variation despite of ICME event. However, over the other areas, the variation associated with ICME event is far more overwhelming.

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Comparison a Forest Fire Spread variation according to weather condition change (기후조건 변화에 따른 산불확산 변화 비교)

  • Lee, Si-Young;Park, Houng-Sek
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 2008.11a
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    • pp.490-494
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    • 2008
  • We simulated a forest fire which was occurred in Yangyang area on 2005 and compared a results between two different weather conditions(real weather condition and mean weather condition since 1968) using FARSITE, which is a forest fire spread simulator for preventing and predicting fire in USDA. And, we researched a problem in the transition for introducing, so we serve the basic method for prevention and attacking fire. In the result, severe weather condition on 2005 effected a forest fire behavior. The rate of spread under real weather condition was about 4 times faster than mean weather condition. Damaged area was about 10 time than mean weather condition. Therefore, Climate change will make a more sever fire season. As we will encounter to need for accurate prediction in near future, it will be necessary to predict a forest fire linked with future wether and fuel condition.

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Introduction for the Necessity and Application Example of the Village-based AWS (마을 단위 AWS 구축의 필요성 및 적용사례 소개)

  • Jo, Won Gi;Kang, Dong-hwan;Kim, MoonSu;Shin, In-Kyu;Kim, HyunKoo
    • Journal of Environmental Science International
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    • v.29 no.10
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    • pp.1003-1010
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    • 2020
  • In this study, the necessity for a village unit Automatic Weather System (AWS) was suggested to obtain correct agricultural weather information by comparing the data of AWS of the weather station with the data of AWS installed in agricultural villages 7 km away. The comparison sites are Hyogyo-ri and Hongseong weather station. The seasonal and monthly averaged and cumulative values of data were calculated and compared. The annual time series and correlation was analyzed to determine the tendency of variation in AWS data. The average values of temperature, relative humidity and wind speed were not much different in comparison with each season. The difference in precipitation was ranged from 13.2 to 91.1 mm. The difference in monthly precipitation ranged from 1.2 to 75.4 mm. The correlation coefficient between temperature, humidity and wind speed was ranged from 0.81 to 0.99 and it of temperature was the highest. The correlation coefficient of precipitation was 0.63 and the lowest among the observed elements. Through this study, precipitation at the weather station and village unit area showed the low correlation and the difference for a quantitative comparison, while the elements excluding precipitation showed the high correlation and the similar annual variation pattern.

Periods of Cold Weather Concrete Determined by Korean and Japanese Codes with Climate Data Obtained from Korea (우리나라 한중콘크리트 적용 기간의 KCI와 AIJ 규정에 따른 비교)

  • Lee, Myung-Ho;Zhao, Yang;Park, Jun-Hee;Han, Min-Cheol;Han, Cheon-Goo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2013.05a
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    • pp.326-328
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    • 2013
  • This study compares the periods of cold weather concrete determined by the codes regulated by KCI (Korean Concrete Institute) and AIJ (Architectural Institute of Japan). For the calculation of the periods of cold weather concrete, the climate data for last 5 years obtained from Korean weather forecast station is used. Calculated data indicated that the period of cold weather concrete by AIJ code is longer than that by KCI code. Although global warming causes the decrease of the period of winter season, the temperature differences are large in Korea. Therefore, it is required that the current KCI code should be accordingly upgraded to reflect the weather variation in Korea over time.

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