• Title/Summary/Keyword: meteorological parameter

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A Statistical Approach to Examine the Impact of Various Meteorological Parameters on Pan Evaporation

  • Pandey, Swati;Kumar, Manoj;Chakraborty, Soubhik;Mahanti, N.C.
    • The Korean Journal of Applied Statistics
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    • v.22 no.3
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    • pp.515-530
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    • 2009
  • Evaporation from surface water bodies is influenced by a number of meteorological parameters. The rate of evaporation is primarily controlled by incoming solar radiation, air and water temperature and wind speed and relative humidity. In the present study, influence of weekly meteorological variables such as air temperature, relative humidity, bright sunshine hours, wind speed, wind velocity, rainfall on rate of evaporation has been examined using 35 years(1971-2005) of meteorological data. Statistical analysis was carried out employing linear regression models. The developed regression models were tested for goodness of fit, multicollinearity along with normality test and constant variance test. These regression models were subsequently validated using the observed and predicted parameter estimates with the meteorological data of the year 2005. Further these models were checked with time order sequence of residual plots to identify the trend of the scatter plot and then new standardized regression models were developed using standardized equations. The highest significant positive correlation was observed between pan evaporation and maximum air temperature. Mean air temperature and wind velocity have highly significant influence on pan evaporation whereas minimum air temperature, relative humidity and wind direction have no such significant influence.

Stratification related to Heat Flux in Deukryang Bay during Summer (여름철 득량만의 열속과 관련한 성층)

  • 최용규;홍성근
    • Journal of Environmental Science International
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    • v.6 no.6
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    • pp.579-588
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    • 1997
  • In order to see the stratification related to the heat flux In Deukryang Bay, the oceanographic data on July 12, 1994 and the meteorological data of Kohung and Kwangju meteorological stations were analysed. The temperature durerences between the sea surface and the near bottom were 1~3 ton spring tide (July 12, 1994) In Deukryang Bay. The temperature anomalies were high about 3t during summer In 1994. These mean that the non mixing was not effective In destroying the stratification due to the sea surface heating by the solar radition, even though it was on spring tide. The maximum solar radiation was about 600 ly/day, which was the value of the same date of oceanographic observation. The sensible and the latent heat flux which are 0~100 ly/day were not so varied during summer. The absorbed heat flux through the sea surface was mostly lost by the back radiation. which ranges are about 0~-400 ly/day. The dimensionless mixing parameter related to the buoyancy flux was 5~150$\times$$10^{-5}$. The efficiency of tidal mixing to destroy the stratecation was 0.4~0.6%.

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A Short-term Forecasting of Water Supply Demands by the Transfer Function Model (Transfer Function 모형을 이용한 수도물 수요의 단기예측)

  • Lee, Jae-Joon
    • Journal of Korean Society of Water and Wastewater
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    • v.10 no.2
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    • pp.88-103
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    • 1996
  • The objective of this study is to develop stochastic and deterministic models which could be used to synthesize water application time series. Adaptive models using mulitivariate ARIMA(Transfer Function Model) are developed for daily urban water use forecasting. The model considers several variables on which water demands is dependent. The dynamic response of water demands to several factors(e.g. weekday, average temperature, minimum temperature, maximum temperature, humidity, cloudiness, rainfall) are characterized in the model by transfer functions. Daily water use data of Kumi city in 1992 are employed for model parameter estimation. Meteorological data of Seonsan station are utilized to input variables because Kumi has no records about the meteorological factor data.To determine the main factors influencing water use, autocorrelogram and cross correlogram analysis are performed. Through the identification, parameter estimation, and diagnostic checking of tentative model, final transfer function models by each month are established. The simulation output by transfer function models are compared to a historical data and shows the good agreement.

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Sensitivity analysis of satellite-retrieved SST using IR data from COMS/MI

  • Park, Eun-Bin;Han, Kyung-Soo;Ryu, Jae-Hyun;Lee, Chang-Suk
    • Korean Journal of Remote Sensing
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    • v.29 no.6
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    • pp.589-593
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    • 2013
  • Sea Surface Temperature (SST) is the temperature close to the ocean's surface and affects the Earth's atmosphere as an important parameter for the climate circulation and change. The SST from satellite still has biases from the error in specifying retrieval coefficients from either forward modeling or instrumental biases. So in this paper, we performed sensitivity analysis using input parameter of the SST to notice that the SST is most affected among the input parameter. We used Infrared (IR) data from the Communication, Ocean, and Meteorological Satellite (COMS)/Meteorological Imager (MI) from April 2011 to March 2012. We also used the Global Space-based Inter-Calibration System (GSICS) correction to quality of the IR data from COMS. SST was calculated by substituting the input parameters; IR data with or without the GSICS correction. The results of this sensitivity analysis, the SST was sensitive from -0.0403 to 0.2743 K when the IR data were changed by the GSICS corrections.

Evaluating the Output of Small-size Wind Power Generators Using Weibull Data (와이블데이터를 이용한 소형풍력발전기 출력에 대한 평가)

  • You, Ki-Pyo;Kim, Young-Moon
    • Journal of the Korean Solar Energy Society
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    • v.32 no.2
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    • pp.95-104
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    • 2012
  • This study purposed to predict wind energy for small size wind power generators at 50m above the ground in each area using mean wind speed data for 10 minutes collected from 2001 to 2011 by meteorological data in large cities having over 60% of 15 story (50m) or higher apartments including Seoul, Daejeon, Gwangju and Daegu representing the inland region, and Busan, Incheon and Ulsan representing the coastal region. In the results of analysis, we confirmed close agree ment between observatory weather data and probability density distribution obtained using Weibull's parameters, and this suggests that Weibull's parameter is applicable to the estimation of wind energy. Hourly output energy using the mean wind speed for 10 minutes and output energy obtained from Weibull's parameter showed an error less than 5%, and thus it was found that wind energy can be evaluated using Weibull's modulus.

Climate Influences of Galactic Cosmic Rays (GCR): Review and Implications for Research Policy (우주기원의 고에너지 입자가 기후에 미치는 영향: 연구 현황과 정책적 시사점)

  • Kim, Jiyoung;Jang, Kun-Il
    • Atmosphere
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    • v.27 no.4
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    • pp.499-509
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    • 2017
  • Possible links among cosmic ray, cloud, and climate have scientific uncertainties. The reputed topics have been highly controversial during several decades. A link between the atmospheric ionization by galactic cosmic rays (GCR), which is modulated by solar activities, and global cloud cover was firstly proposed in 1997. Some researchers suggested that the GCR can stimulate the formation of cloud condensation nuclei (CCN) in the atmosphere, and then the higher CCN concentrations may lead to an increase of cloud cover, resulting in a cooling of the Earth's climate, and vise versa. The CLOUD (Cosmic leaving outdoor droplets) experiment was designed to study the effect of GCR on the formation of atmospheric aerosols and clouds under precisely controlled laboratory conditions. A state-of-the-art chamber experiment has greatly advanced our scientific understanding of the aerosol formation in early stage and its nucleation processes if the GCR effect is considered or not. Many studies on the climate-GCR (or space weather) connection including the CLOUD experiment have been carried out during the several decades. Although it may not be easy to clarify the physical connection, the recent scientific approaches such as the laboratory experiments or modeling studies give some implications that the research definitively contributed to reduce the scientific uncertainties of natural and anthropogenic aerosol radiative forcing as well as to better understand the formation processes of fine particulate matters as an important parameter of air quality forecast.

Introduction to Simulation Activity for CMDPS Evaluation Using Radiative Transfer Model

  • Shin, In-Chul;Chung, Chu-Yong;Ahn, Myoung-Hwan;Ou, Mi-Lim
    • Proceedings of the KSRS Conference
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    • 2007.10a
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    • pp.282-285
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    • 2007
  • Satellite observed brightness temperature simulation using a radiative transfer model (here after, RTM) is useful for various fields, for example sensor design and channel selection by using theoretically calculated radiance data, development of satellite data processing algorithm and algorithm parameter determination before launch. This study is focused on elaborating the simulation procedure, and analyzing of difference between observed and modelled clear sky brightness temperatures. For the CMDPS (COMS Meteorological Data Processing System) development, the simulated clear sky brightness temperatures are used to determine whether the corresponding pixels are cloud-contaminated in cloud mask algorithm as a reference data. Also it provides important information for calibrating satellite observed radiances. Meanwhile, simulated brightness temperatures of COMS channels plan to be used for assessing the CMDPS performance test. For these applications, the RTM requires fast calculation and high accuracy. The simulated clear sky brightness temperatures are compared with those of MTSAT-1R observation to assess the model performance and the quality of the observation. The results show that there is good agreement in the ocean mostly, while in the land disagreement is partially found due to surface characteristics such as land surface temperature, surface vegetation, terrain effect, and so on.

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Characteristics of Surface High Ozone Concentration on Pusan Coastal area, Korea (부산 해안지역의 고농도 오존 발생 특성에 관한 연구)

  • 전병일
    • Journal of Environmental Science International
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    • v.9 no.4
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    • pp.295-302
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    • 2000
  • This study was conducted to investigate the characteristics of surface ozone concentration and occurrence of high ozone concentration using hourly ozone, nitrogen dioxide and meteorological data for 1997~1998 in Pusan coastal area. Monthly mean ozone concentration was the highest at Dongsamdong in Spring(35.4ppb), at Kwangbokdong in Fall(25.1ppb) and the lowest Dongsamdong(22.2ppb) and Kwangbokdong(16.0ppb) in Winter. Relative standard deviation indicating clearness of observation site was 0.42 at Dongsamdong and 0.49 at Kwangbokdong that is similar to urban area. The diurnal variation of ozone concentration of Dongsamdong and Kwangbokdong showed maximum at 1500~1600LST and minimum 0700~0800LST that typical pattern of ozone concentration. In ozone episode period(Sept. 10~15, 1998), diurnal change of ozone concentration was very high, and ozone concentration was related to meteorological parameters such as temperature, relative humidity, wind speed, cloud amount and radiation on a horizontal surface. During the episode days peak ozone concentrations are much higher than the normal values, wind speeds are always lower, and solar radiation is high with the exception of the September episode.

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Seasonal Variations of $SO_2$Dry Deposition Velocity Obtained by Sonic Anemometer-Thermometer (초음파 풍속온도계를 이용한 $SO_2$건성침착속도의 계절변화 특징)

  • 이종범;박세영
    • Journal of Korean Society for Atmospheric Environment
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    • v.14 no.5
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    • pp.465-478
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    • 1998
  • In this study, seasonal variations of the dry deposition velocity and deposition flux for the sulfur dioxide were analysed. The field observation was performed during one year (from November 1, 1995 to October 31, 1996) in Chunchon basin. The turbulence data were measured by 3-dimensional sonic anemometer/thermometer, and were estimated by mean meteorological data obtained at two heights (2.5 m and 10 m) of meteorological tower. Also, the estimation methods were evaluated by comparing the turbulence data. The results showed that the estimated dry deposition velocity and turbulence parameter such as uc and sensible heat flux using mean meteorological data were relatively similar to the sonic measurements, but all showed somewhat large differences. The dry deposition velocity was large in summer and small in winter mainly due to canopy resistance (rc). The major factor which affects diurnal variation of the velocity was aerodynamic resistance (rw). The SO2 dry deposition flux was large in winter and small in summer in Chunchon.

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Early Instrumental Earthquake Data (1905-1942) in Korea (한반도 초기 계기지진 자료 (1905-1942))

  • 전명순;전정수
    • Economic and Environmental Geology
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    • v.34 no.6
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    • pp.573-581
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    • 2001
  • 110 earthquake parameters (origin time, epicentral location and magnitude) were determined from 533 event records between 1905 and 1942 using data mainly from the "Annual Report of the Meteorological Observatory of the Government General of Tyosen" We adopted epicentral coordinates from the original reports for 34 events and from the Japanese Central Meteorological Observatory far another .34 events. We determined epicenters for 37 events using arrival time information from the reports. We adopted 4 epicenters from the International Seismological Summary and I from the Chinese bulletin. To determine the magnitude, we applied Tsuboi (1954) formula which is currently employed by Korea Meteorological Administration (KMA) for 94 events. For 16 events, we determined magnitude from the reef)reed felt epicentral areal using the correlation equation between known magnitude and felt area.

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