• 대기
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• 제26권1호
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• pp.73-84
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• 2016

A method to make ice spike using home refrigerator with ice tray was found. Many experiments have carried out with this method and many natural phenomena occurring on the formation of ice spike are found. A new concept of the Latter Freezing Water (LFW) was imported to explain the ice spike formation. At LFW position on water surface, the Sprout of Super cooled Water (SSW) grows by the Volume Expansion Effect (VEE) caused by the phase change of water in water. And air bubbles that are expelled from ice during freezing process, gather, rise, and detonate at the upper most part of SSW that make SSW freeze and grow upward with the water pipe in it. Together with VEE the capillarity in the water pipe makes the column grow more, that makes the ice spike. Many other findings were succeeded; 1) Ice spike process is completed before the whole water freezes. 2) If water is corrupted or shocked, even though it is very slight, ice spike is not generated. 3) Rain water contains the most LFW among all kind of waters used in experiments. 4) LFW is changed into normal water after passing the ice spike. 5) A new concept of the ice bullet is introduced. 6) The reason of frequent occurrences of the ice spike at Mt. Mai is investigated also.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2000년도 추계 학술대회지
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• pp.46-78
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• 2000

This paper is to introduce recent collaborative activities in agricultural weather information services among institutions in Korea as well as key concepts for understanding agrometeorological services. KMA and RDA have agreed upon the establishment of the Joint Committee for Agrometeorolgy at national level to strengthen the national agrometeorological services in data collection, information production, research, and services to end-users of agrometeorological information in Korea. Several on-going joint projects in agrometeorology by RDA/KMA are introduced in brief. The projects being developed are : Strengthening of the Joint Committee of agrometeorology, Extension of observation network for agricultural weather, Production of the detailed agrometeorological information based on numerical weather forecasts, Development of seasonal and interannual weather forecasts for agricultural applications, Information network system for supporting agrometeorological research, and Improvement of agrometeorological information services at national and regional level. Strengthening of programs for the education and training of agrometeorologists will be impending responsibilities of the government. The government must consider establishment of organizations dedicated to and in charge of national agrometeorological services to end-users. RDA and KMA should play a major role to obtain this goal, based on a close cooperation with universities, scientific societies, and other relevant institutions. If this plan is successful, major infrastructures and services in agrometeorology shall be established in the next 5 years, and we can contribute to regional and global societies through sharing experiences and know-hows.

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2003년도 Proceedings of the international symposium on the fusion technology
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• pp.379-382
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• 2003

In gravity data correction process, mass effect of the upper part of base level is removed with Bouguer density. Usually, Bouguer density is estimated as a mean density in the field area. But, this may causes a serious problem when ore body is in the area. To overcome this problem, we tried to apply a new method mixing up mass corrections and inversion (3DGTI). 3-D Gravity Terrain Inversion (3DGTI) includes information of topography and distribution of Bouguer density. For this method does not remove the mass effect above base level, it is no longer useless to use Bouguer density. Numerical model tests have shown that the 3DGIT successfully retrieves the anomalous subsurface density distribution of both surface and deeper layers. Model tests shows that this method shows better results than those of conventional one, especially when main target is ore body. The inversion result well delineates the three-dimensional shape of the intruded granite body and basement.

• 암석학회지
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• 제20권4호
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• pp.243-250
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• 2011

백두산 화산으로부터 분화된 것으로 추정되는 1702년의 역사기록을 화산학적 견지에서 고찰하였다. 분화지점인 백두산으로부터 140 km 떨어진 2 장소에서의 강하화산재의 등층후선을 설정하여 경험식에 의하여 계산된 분출물의 최소량은 $1.2km^3$로 1702년의 백두산 분화 사건은 화산폭발지수 5에 해당하는 대규모 분화였다. 플리니안 분화에 의한, 열기를 가진 화산재구름이 바람의 영향 하에 지면 가까이 낮은 고도로 이동하면서 강하화산재가 발생 퇴적된 것을 잘 묘사하고 있다. 향후 분화에 대비하여 역사기록에 대한 철저한 분석을 통한 화산의 특성 이해가 절실하다.

• 한국환경과학회지
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• 제25권1호
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• pp.163-171
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• 2016

We analyzed the characteristics of fog formation in the Gumi Reservoir of Nakdong river with the field observation data for recent 2 years (1 April 2013~31 March 2015) collected by the national institute of meteorological research, KMA. In early morning, we frequently observe the steam rising from the water surface. The fog occurs from adding water vapor into the air. We call the fog as steam fog. Steam fogs occur when cold, dry air mixes with warm, moist air above a water surface. The steam fog appears mainly in autumn under the following conditions; (1) sensible heat is positive values ($10{\sim}20W/m^2$), (2) latent heat is more positive values ($25{\sim}35W/m^2$) than sensible heat, (3) cloudless nights with light winds (about 1.5 m/s), (4) under condition(3), mountainous winds easily blows into the reservoir.

• 한국환경과학회지
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• 제31권12호
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• pp.999-1012
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• 2022

To investigate the reason for the spatial difference in PM_2.5 (Particulate Matter, < 2.5 ㎛) concentration despite a similar synoptic pattern, a synoptic analysis was performed. The data used for this study were the daily average PM_2.5 concentration and meteorological data observed from 2016 to 2020 in Busan and Seoul metropolitan areas. Synoptic pressure patterns associated with high PM_2.5 concentration episodes (greater than 35 ㎍/m³) were analyzed using K-means cluster analysis, based on the 900 hPa geopotential height of NCEP (National Centers for Environmental Prediction) FNL (Final analysis) data. The analysis identified three sub-groups related to high concentrations occurring only in Busan and Seoul metropolitan areas. Although the synoptic patterns of high PM_2.5 concentration episodes that occur independently in Busan and Seoul metropolitan areas were similar, there was a difference in the intensity of pressure gradient and its direction, which tends to be an important factor determining the movement time of pollutants. The spatial difference in PM_2.5 concentration in the Korean Peninsula is due to the difference and direction of the atmospheric pressure gradient that develops from southwest to northeast direction.

• 한국지구과학회지
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• 제30권7호
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• pp.845-854
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• 2009

북한의 풍력발전 가능성을 조사하기 위한 첫 단계로 북한 지역에서의 30년 동안의 27개 지점의 지상관측자료 중 풍속과 풍향 자료를 이용하여 이 지역에서의 기후학적 바람 자원을 분석하였다. 바람자원 분석을 위해 풍속의 확률 밀도함수를 Weibull 함수로 가정하여 접근하였다. 지표로부터 50 m 고도에서 연중 평균 풍속이 4.0 m/s 이상인 지역은 대체적으로 개마고원 지역과 황해도 해안 지역이었다. 이 지역들은 비교적 바람 자원이 풍부한 것으로 나타났다. 풍속이 5 m/s 이상을 유지하는 지속시간이 가장 긴 계절은 봄이었고, 짧은 계절은 여름이었다. 관측 지점 중 장진과 양덕이 지속시간이 가장 길고 평균 풍속도 가장 큰 곳이었다.

• 한국지구과학회지
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• 제38권7호
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• pp.469-480
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• 2017

Controversy has surrounded the potential impacts of phytoplankton on the tropical climate, since climate models produce diverse behaviors in terms of the equatorial mean state and El $Ni{\tilde{n}}o$-Southern Oscillation (ENSO) amplitude. We explored biophysical impacts on the tropical ocean temperature using an ocean general circulation model coupled to a biogeochemistry model in which chlorophyll can modify solar attenuation and in turn feed back to ocean physics. Compared with a control model run excluding biophysical processes, our model with biogeochemistry showed that subsurface chlorophyll concentrations led to an increase in sea surface temperature (particularly in the western Pacific) via horizontal accumulation of heat contents. In the central Pacific, however, a mild cold anomaly appeared, accompanying the strengthened westward currents. The magnitude and skewness of ENSO were also modulated by biophysical feedbacks resulting from the chlorophyll affecting El $Ni{\tilde{n}}o$ and La $Ni{\tilde{n}}a$ in an asymmetric way. That is, El $Ni{\tilde{n}}o$ conditions were intensified by the higher contribution of the second baroclinic mode to sea surface temperature anomalies, whereas La $Ni{\tilde{n}}a$ conditions were slightly weakened by the absorption of shortwave radiation by phytoplankton. In our model experiments, the intensification of El $Ni{\tilde{n}}o$ was more dominant than the dampening of La $Ni{\tilde{n}}a$, resulting in the amplification of ENSO and higher skewness.

• 한국지구과학회지
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• 제26권2호
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• pp.149-159
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• 2005

Simultaneous observations of MODIS (Moderate-resolution Imaging Spectroradiometer) onboard the Aqua and Terra satellites and weather station at ground near the Inchon International Airport (37.2-37.7 N, 125.7-127.2 E) during the period from December 2002 to September 2004 have been utilized in order to analyze the characteristics of satellite-observed infrared (IR) and visible data under fog and clear-sky conditions, respectively. The differences $(T_{3.7-11})$ in brightness temperature between $3.75{\mu}m\;and\;11.0{\mu}m$ were used as threshold values for remote-sensing fog (or low clouds) from satellite during day and night. The $T_{3.7-11}$ value during daytime was greater by about 21 K when it was foggy than that when it was clear, but during nighttime fog it was less by 1.5 K than during nighttime clear-sky. The value was changed due to different values of emission of fog particles at the wavelength. Since the near-IR channel at $3.7{\mu}m$ was affected by solar and IR radiations in the daytime, both IR and visible channels (or reflectance) have been used to detect fog. The reflectance during fog was higher by 0.05-0.6 than that during clear-sky, and varied seasonally. In this study, the threshold values included uncertainties when clouds existed above a layer of fog.

• 한국환경생태학회지
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• 제26권6호
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• pp.876-883
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• 2012

맹꽁이의 번식활동에 영향을 주는 기상요인을 분석하기 위해 2008년부터 2011년까지 4년 동안 제주도 대정읍에 위치한 산란지에서 조사하였다. 분석요인은 강우량, 습도, 온도, 기압, 풍속으로 강우가 있는 날에 산란유무를 가지고 비교분석을 하였다. 분석결과 맹꽁이의 번식활동에 영향을 주는 요인은 강우량, 습도, 기압으로 나타났다. 이 중에서 가장 큰 영향을 주는 요인은 강우량으로 나타났다. 맹꽁이는 많은 비가 내릴 때 산란활동에 참가하는 것으로 나타났으며, 습도와 기압도 번식활동에 어느 정도 영향을 주는 것으로 분석되었다. 온도인 경우는 번식기간이 여름철이므로 이미 번식활동에 필요한 조건을 충족시킨 것으로 판단하였다. 따라서 맹꽁이도 온대지방에서 이루어진 다른 무미류 연구에서와 같이 강우량과 온도의 영향을 많이 받고 있다는 것이 확인되었다.