• Title/Summary/Keyword: Meteorological Factor

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The Change in Fuel Moisture Contents on the Forest Floor after Rainfall

  • Songhee Han;Heemun Chae
    • Journal of Forest and Environmental Science
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    • v.39 no.4
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    • pp.235-245
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    • 2023
  • Forest fuel moisture content is a crucial factor influencing the combustion rate and fuel consumption during forest fires, significantly impacting the occurrence and spread of wildfires. In this study, meteorological data were gathered using a meteorological measuring device (HOBO data logger) installed in the south and north slopes of Kangwon National University Forest, as well as on bare land outside the forest, from November 1, 2021, to October 31, 2022. The objective was to analyze the relationship between meteorological data and fuel moisture content. Fuel moisture content from the ground cover on the south and north slopes was collected. Fallen leaves on the ground were utilized, with a focus on broad-leaved trees (Prunus serrulata, Quercus dentata, Quercus mongolica, and Castanea crenata) and coniferous trees (Pinus densiflora and Pinus koraiensis), categorized by species. Additionally, correlation analysis with fuel moisture content was conducted using temperature (average, maximum, and minimum), humidity (average, minimum), illuminance (average, maximum, and minimum), and wind speed (average, maximum, and minimum) data collected by meteorological measuring devices in the study area. The results indicated a significant correlation between meteorological factors such as temperature, humidity, illuminance, and wind speed, and the moisture content of fuels. Notably, exceptions were observed for the moisture content of the on the north slope and that of the ground cover of Prunus serrulata and Castanea crenata.

Sensitivity Analysis of Global Wind-Wave Model (전지구 파랑 예측시스템의 민감도 분석)

  • Park, Jong Suk;Kang, KiRyong
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.24 no.5
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    • pp.333-342
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    • 2012
  • We studied the characteristics of spatial distribution of global wave height and carried out the modelsensitivity test by changing the input field, model resolution and physical factor (effective wind factor) since the spatial and temporal resolution in wind wave forecasting is one of most important factors. Comparisons among the different cases, and also between model, buoy and satellite data have been made. As a results of the wind-wave model run using the high resolution wind field, the bias of significant wave height showed the positive tendency and the Root-Mean Square Error(RMSE) was a bit decreased based on the comparison with buoy data. When the model resolution was changed to higher, the bias and RMSE was increased, and as the effective wind factor was smaller than default value(= 1.4) the bias and RMSE showed also decreasing pattern.

Comparison between Expected and Actual Capacity Factors of a Wind Farm (풍력발전단지의 예측이용율과 실제이용율 비교분석에 관한 연구)

  • Koh, Byung-Euk;Moon, Seung-Jae;Yoo, Hoseon
    • Plant Journal
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    • v.7 no.1
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    • pp.40-48
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    • 2011
  • This study shows the comparison between expected and actual capacity factors of a wind farm through wind resource analyzation. The expected capacity factor comes from an 'automatic weather system' run by the Korean national weather service and a 'meteorological mast' run by a project owner. Based on this comparison and analysis, the importance of meteorological mast micro-siting and selection of wind turbine class and type, will be studied along with presenting important implications for wind farm expansion and development.

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On the Seasonal Prediction of Traffic Accidents in Relation to the Weather Elements in Pusan Area (기상요소에 따른 부산지역 계절별 교통사고 변화와 예측에 관한 연구)

  • 이동인;이문철;유철환;이상구;이철기
    • Journal of Environmental Science International
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    • v.9 no.6
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    • pp.469-474
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    • 2000
  • The traffic accidents in large cities such as Pusan metropolitan city have been increased every year due to increasing of vehicles numbers as well as the gravitation of the population. In addition to the carelessness of drivers, many meteorological factors have a great influence on the traffic accidents. Especially, the number of traffic accidents is governed by precipitation, visibility, cloud amounts temperature, etc. In this study, we have analyzed various data of meteorological factors from 1992 to 1997 and determined the standardized values for contributing to each traffic accident. Using the relationship between meteorological factors(visibility, precipitation, relative humidity and cloud amounts) and the total automobile mishaps, and experimental prediction formula for their traffic accident rates was seasonally obtained at Pusan city in 1997. Therefore, these prediction formulas at each meteorological factor may by used to predict the seasonal traffic accident numbers and contributed to estimate the variation of its value according to the weather condition it Pusan city.

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Annual Variation of $CO_2$ and CH$_4$ Concentration in the Background Area of the Korean Peninsula

  • Park, Jae-Cheon;Park, Byoung-Cheol;Park, Ki-Jun;Chung, Hyo-Sang
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2003.11a
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    • pp.512-513
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    • 2003
  • Human activities have become a major factor that significantly changes the global environment. Mankind has increasingly used land, water, minerals and other natural resources since the beginning of industrialization, and future growth in the population and economy is thought to further enhance the impact upon the Earth. The global climate, biogeochemical process and natural ecosystems are closely linked with one another, and changes in any one of these systems may effect the others, which could result in consequences detrimental to humans and other living organisms on the Earth.(omitted)

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Characteristics of Air Stagnation over the Korean Peninsula and Projection Using Regional Climate Model of HadGEM3-RA (한반도 대기정체의 특성 및 지역기후모델 HadGEM3-RA를 이용한 미래 전망)

  • Kim, Do-Hyun;Kim, Jin-Uk;Kim, Tae-Jun;Byon, Jae-Young;Kim, Jin-Won;Kwon, Sang-Hoon;Kim, Yeon-Hee
    • Atmosphere
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    • v.30 no.4
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    • pp.377-390
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    • 2020
  • Not only emissions, but also atmospheric circulation is a key factor that affects local particulate matters (PM) concentrations in Korea through ventilation effects and transboundary transports. As part of the atmospheric circulation, air stagnation especially adversely affects local air quality due to weak ventilation. This study investigates the large-scale circulation related to air stagnation over Korea during winter and projects the climate change impacts on atmospheric patterns, using observed PM data, reanalysis and regional climate projections from HadGEM3-RA with Modified Korea Particulate matter Index. Results show that the stagnation affects the PM concentration, accompanied by pressure ridge at upper troposphere and weaken zonal pressure gradient at lower troposphere. Downscaling using HadGEM3-RA is found to yield Added-Value in the simulated low tropospheric winds. For projection of future stagnation, SSP5-8.5 and SSP1-2.6 (high and low emission) scenarios are used here. It has been found that the stagnation condition occurs more frequently by 11% under SSP5-8.5 and by 5% under SSP1-2.6 than in present-day climate and is most affected by changes in surface wind speed. The increase in the stagnation conditions is related to anticyclonic circulation anomaly at upper troposphere and weaken meridional pressure gradient at lower troposphere. Considering that the present East Asian winter monsoon is mainly affected by change in zonal pressure gradient, it is worth paying attention to this change in the meridional gradient. Our results suggest that future warming condition increase the frequency of air stagnation over Korea during winter with response of atmospheric circulation and its nonlinearity.

A Study on the Critical Meteorological Factors Influencing the Flight Cancelation and Delay: Focusing on Domestic Airports (국내 항공운항에서 기상현상이 결항 및 지연에 미치는 영향 분석)

  • Lee, Joong-Woo;Ko, Kwnag-Kun;Kwon, Tae-Sun;Lee, Ki-Kwang
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.19 no.1
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    • pp.29-37
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    • 2011
  • Last April, Europe was severly damaged as all social and economic activities came to a halt prompted by the cancellation of all flights resulting from volcanic ash. This exemplifies that the meteorology conditions have significant influence on the flights of airplanes. Hence, in this research the influence that the meteorology has on the domestic flights and its characteristics will be examined, and the core meteorological factors that influence flights in each airport will be drawn. In order to do this, statistical analysis on the influence that the meteorology has on flights was carried out in order to analyze the data about flight cancelation and delay and also its cause, primarily based on the Gimpo, Gimhae, and the Jeju airports. As a result, first, the meteorological factors which impact flight cancellation and delay were different among the domestic airports, and second, it was analyzed that fog was the main meteorological factor in the Gimpo airport, strong wind in the Jeju airport, and fog in the Gimhae airport. Third, between the day the flights were cancelled and delayed occurred, and the day that weren't, the fact that there existed a difference among the actual meteorological factors was statistically drawn. With the result of such analysis, meteorological factors pertaining to the cancellation and delay of flights must be considered seperately by each airport and specialized meteorological information must be provided accordingly. Further, when selecting the position of an airport that is to be constructed in the future, implications that there is a definite need for the meteorology effect evaluation based on past meteorology data can be drawn.

Sixty-year History of the Korean Meteorological Society (한국기상학회 60년사)

  • Tae-Young Lee;Myoung-Seok Suh
    • Atmosphere
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    • v.33 no.2
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    • pp.247-263
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    • 2023
  • A brief history of the Korean Meteorological Society (KMS) is presented for the 60-year period (1963~2022). And academic activities during the period are examined to evaluate their contributions to the achievement of the KMS's goal, that is, the advance of meteorology and circulation of meteorological knowledge. Membership of the KMS was less than 300 before 1990, but increased fast afterwards, exceeding 1000, 2000 and 3000 in 2002, 2014 and 2019, respectively. After 1990, 11 professional committees were set up gradually and played important roles in the advances of professional fields. Size of the KMS budget grew gradually in the 1990s and faster during the 2000s, showing fluctuations in the 2010s. The KMS has been quite active in academic activities such as academic journals, domestic and international conferences, and book publishing. The Journal of the KMS (JKMS) has led the advance of meteorology in Korea since the beginning of the KMS, while "Asia-Pacific Journal of Atmospheric Sciences", which succeeded the JKMS in 2008, has been showing significant paper contributions from scientists around the world and increase of impact factor. Total number of presentations in the regular KMS conferences for the 2010s is 5 times larger than that for the 1990s, with a significant diversification of subject area. Internationally, the trilateral conference of the meteorological societies of Korea, China and Japan had been held since 2005. In 2015, the 3 societies stopped the conference and, instead, launched "Asian Conference on Meteorology". Meanwhile, the KMS has published glossaries, dictionaries, and textbooks of atmospheric sciences.

A Study on the Relationship of Air Pollution and Meteorological Factors : Focusing at Kwanghwamun in Seoul (대기오염농도와 기상인자의 관련성 연구: 서울 광화문지점을 중심으로)

  • 신찬기;한진석;김윤신
    • Journal of Korean Society for Atmospheric Environment
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    • v.8 no.4
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    • pp.213-220
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    • 1992
  • Simple correlation analysis, factor analysis, and multi-variate analysis have been performed to analyze the relationship between air pollution and meteorological factors for air pollution and meteorological data measured at Kwanghwamun in Seoul during the period of one year(January 1990 $\sim$ December 1990). As a result of simple correlation and factor analysis, $SO_2$, TSP and CO concentrations have shown high negative correlation with temperature and among these indicating that these are related with pollutant emission trend based upon heating fuel usage. Ozone has a good corrleation with solar radiation and relative humidity to have a closed relation with $O_3$ generation reaction mechanism. The result of multi-variate correlation analysis shows that the concentration of $SO_2$ and CO are adequate for correlation model with ambient temperature and wind speed and $O_3$ concentrations are adequate for that with solar radiation and wind speed. $SO_2$ and CO levels are considered to be affected first of all by heating fuel usage as a emssion source and wind speed as a dispersion effect. The $SO_2$ concentration in the condition that the temperature fall below zero is explained by multilicative model with wind speed, only one variable.

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On the Evapotranspiration Model derived from the Meteorological Elements and Penman equation (Penman 식과 기상요소를 이용한 증발산모델에 관하여)

  • 이광호
    • Water for future
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    • v.6 no.2
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    • pp.6-11
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    • 1973
  • This paper include the hydrometeorological analyses of evapotranspiration which is import factor concerning the estimate of water budgest over a certain basin. Evapotranspiration model mode by the multiple regression analysis between the evapotranspiration measured on various kinds of ground cover (water, bare soil and lawn) and the other meteorological elements affecting the evapotranspiration process, and the simple regression analysis between the evapo transpiration measured on each ground cover and the evapotranspiration on water and vegetables calculated from the Penman equation. It is expected that the evapotranspiration models are a very useful formulae estimating ten days amounts or a month's amounts.

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