• 제목/요약/키워드: EL Nino

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접합모형을 이용한 경년 및 계절안 진동 모사실험 연구 (On the Study of Intraseasonal and Interannual Oscillations Simulation by using Coupled Model)

  • 안중배
    • 한국환경과학회지
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    • 제8권6호
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    • pp.645-652
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    • 1999
  • In order to simulate and investigate the major characteristics of El Nino/Southern Oscillation(ENSO) and Madden Jullian Oscillation(MJO), an intermediate type atmosphere-ocean coupled model is developed and their results are examined. The atmosphere model is a time-dependent non-linear perturbation moist model which can determine the internal heating for itself. The counterpart of the atmosphere model is GCM-type tropical ocean model which has fine horizontal and vertical grid resolutions. In the coupled experiment, warm SST anomaly and increased precipitation and eastward wind and current anomalies associated with ENSO and MJO are properly simulated in Pacific and Indian Oceans. In spite of some discrepancies in simulation MJO, the observed atmospheric and oceanic low-frequency characteristics in the tropics are successfully identified. Among them, positive SST anomalies centered at the 100m-depth of tropical eastern-central Pacific due to the eastward advection of warm water and reduced equatorial upwelling, and negative anomalies in the Indian and western Pacific seem to be the fundamental features of tropical low-frequency oscillations.

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Distribution of Tropical Tropospheric Ozone Determined by the Scan-Angle Method applied to TOMS Measurements

  • Kim, Jae-H.;Na, Sun-Mi;Newchurch, M. J.;Emmons, L.
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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    • pp.7-11
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    • 2002
  • This study introduces the first method that determines tropospheric ozone column directly from a space-based instrument. This method is based on the physical differences in the Total Ozone Mapping Spectrometer (TOMS) measurement as a function of its scan-angle geometry. Tropospheric ozone in September-October exhibits a broad enhancement over South America, the southern Atlantic Ocean, and western South Africa and a minimum over the central Pacific Ocean. Tropical tropospheric ozone south of the equator is higher than north of the equator in September-October, the southern burning season. Conversely, ozone north of the equator is higher in March, the northern burning season. Overall, the ozone over the southern tropics during September-October is significantly higher than over the northern tropics. Abnormally high tropospheric ozone occurs over the western Pacific Ocean during the El Nino season when the ozone amounts are as high as the ozone over the Africa.

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미호천 유역의 시단위 연최대치 강우계열의 경향성 및 기후변동을 고려한 비정상성 빈도분석 (Non-stationarity Analysis with Trend and Climate Variability for Annual Maximum of Hourly Rainfall in Miho watershed)

  • 이정기;김병식;김형수
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2012년도 학술발표회
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    • pp.345-345
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    • 2012
  • 정상성 기반의 전통적 극한치 이론은 기후변화 및 변동에 의한 외부변화 요인을 반영하기에는 한계가 있음이 지적되어왔다. 따라서 강우의 빈도분석 시 매개변수의 시간에 따른 변화를 반영한 비정상성 빈도분석 방법이 필요하다. 본 연구에서는 미호천 유역의 강우관측소 중 기상청에서 관리하는 청주 관측소 및 국토해양부에서 관리하는 가덕, 병천, 증평, 진천 관측소의 24시간 연최대치 강우자료를 대상으로 시간에 따른 경향성 분석을 하였다. 또한 자료의 경향성을 고려하여 비정상성 빈도분석을 하였고 외부상관기상변수로써 ENSO(El Nino Southern Oscillation)를 이용하여 비정상성 빈도분석을 실시하였다.

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Study on Multiscale Analysis on Drought Characteristics

  • Uranchimeg, Sumiya;Kwon, Hyun Han
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2015년도 학술발표회
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    • pp.611-611
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    • 2015
  • One of the hazard of nature is a drought. Its impact varies from region to region and it is difficult for people to understand and define due to differences in hydrometeorological and social economic aspects across much of the country. In the most general sense, drought originates from a deficiency of precipitation over an extended period of time, usually month, season or more, resulting in a water shortage for some activity, group, or environmental sector. Palmer Drought Severity Index (PDSI) is well known and has been used to study aridity changes in modern and past climates. The PDSI index is estimated over US using USHCN historical data.(e.g. precipitation, temperature, latitude and soil moisture). In this study, low frequency drought variability associated with climate variability such as El-Nino and ENSO is mainly investigated. With respect to the multi-scale analysis, wavelet transform analysis is applied to the PDSI index in order to extract the low frequency band corresponding to 2-8 years. Finally, low frequency patterns associated with drought by comparing global wavelet power, with significance test are explored.

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Variability in Environmental Flow Metrics to Hydroclimatic Extremes

  • Kim, Jong-Suk
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2017년도 학술발표회
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    • pp.195-195
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    • 2017
  • The patterns of occurrence of typhoons in North Pacific region are constantly changing with the increase of temperature in sea surface and the occurrence of El Nino and La Nina and changes of their development caused by global warming. In addition, alterations of flow regimes caused by large-scale hydraulic construction projects in the past few years and changes in precipitation patterns caused by climate change have imposed increased stress on hydroecology while the indiscreet utilization of water resources has a negative environmental impact on the water flows in the natural rivers and streams and hydroecological structures. The purpose of this study is to explore the impact of altered hydrologic regime on stream and riparian ecosystems that are most vulnerable to climate variability and extremes such as typhoons.

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한국기상학회 기후역학 분야 학술 발전 현황 (Academic Development Status of Climate Dynamics in Korean Meteorological Society)

  • 안순일;예상욱;서경환;국종성;김백민;김대현
    • 대기
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    • 제33권2호
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    • pp.125-154
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    • 2023
  • Since the Korean Meteorological Society was organized in 1963, the climate dynamics fields have been made remarkable progress. Here, we documented the academic developments in the area of climate dynamics performed by members of Korean Meteorological Society, based on studies that have been published mainly in the Journal of Korean Meteorological Society, Atmosphere, and Asia-Pacific Journal of Atmospheric Sciences. In these journals, the fundamental principles of typical ocean-atmosphere climatic phenomena such as El Niño, Madden-Julian Oscillation, Pacific Decadal Oscillation, and Atlantic Multi-decadal Oscillation, their modeling, prediction, and its impact, are being conducted by members of Korean Meteorological Society. Recently, research has been expanded to almost all climatic factors including cryosphere and biosphere, as well as areas from a global perspective, not limited to one region. In addition, research using an artificial intelligence (AI), which can be called a cutting-edge field, has been actively conducted. In this paper, topics including intra-seasonal and Madden-Julian Oscillations, East Asian summer monsoon, El Niño-Southern Oscillation, mid-latitude and polar climate variations and some paleo climate and ecosystem studies, of which driving mechanism, modeling, prediction, and global impact, are particularly documented.

CMIP5 기후 모형에서 나타나는 북서태평양 아열대 고기압의 변동성 (Variability of the Western North Pacific Subtropical High in the CMIP5 Coupled Climate Models)

  • 김은진;권민호;이강진
    • 대기
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    • 제26권4호
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    • pp.687-696
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    • 2016
  • The western North Pacific subtropical high (WNPSH) in boreal summer has interannual and interdecadal variability, which affects East Asian summer monsoon variability. In particular, it is well known that the intensity of WNPSH is reversely related to that of summer monsoon in North East Asia in association with Pacific Japan (PJ)-like pattern. Many coupled climate models weakly simulate this large-scale teleconnection pattern and also exhibit the diverse variability of WNPSH. This study discusses the inter-model differences of WNPSH simulated by different climate models, which participate in the Coupled Model Intercomparison Project phase 5 (CMIP5). In comparing with reanalysis observation, the 29 CMIP5 models could be assorted into two difference groups in terms of interannual variability of WNPSH. This study also discusses the dynamical or thermodynamics factors for the differences of two groups of the CMIP5 climate models. As results, the regressed precipitation in well-simulating group onto the Nino3.4 index ($5^{\circ}N-5^{\circ}S$, $170^{\circ}W-120^{\circ}W$) is stronger than that in poorly-simulating group. We suggest that this difference of two groups of the CMIP5 climate models would have an effect on simulating the interannual variability of WNPSH.

기후변동을 고려한 조건부 GEV 분포를 이용한 비정상성 빈도분석 (Non-stationary Frequency Analysis with Climate Variability using Conditional Generalized Extreme Value Distribution)

  • 김병식;이정기;김형수;이진원
    • 한국습지학회지
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    • 제13권3호
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    • pp.499-514
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    • 2011
  • 전통적 수문빈도분석의 기본가정은 기후와 수문사상이 정상성이라는 것으로 즉, 분포형의 매개변수들이 시간에 따라 불변이라는 것이다. 댐, 제방, 운하, 교량 등 수공 관련 기간시설물을 계획하고 설계할 때는 과거 상황을 이해하고 미래에도 그 상황이 유지될 것이라는 것을 근거로 한다. 그러나 현실은 기본가정과는 달리 수문자료들은 비정상성을 지니고 있으며 수자원관리자들에 의해 항상 기간시설물을 계획하고 설계 할 때 비정상성을 다루고자 끊임없이 노력해 왔다. 본 논문에서는 비정상성 수문빈도분석기법을 소개하고, 조건부 Generalized Extreme Value(GEV) 분포를 이용하여 비정상성 빈도분석을 실시하였다. 본 논문에서는 6개 기상관측소지점의 24시간 연최고치 강우량을 대상으로 비정상성 빈도분석을 실시하였으며 최우도법(Maximum Likelihood)을 사용하여 GEV 분포형의 매개변수를 추정하였다. 그 결과 비정상성 GEV 분포가 확률 강우량을 산정하는데 있어 적합함을 확인 할 수 있었다. 또한 ENSO(El Nino Southern Oscillation)를 나타내는 지수인 SOI(Southern Oscillation Index)를 이용하여 기후변동 고려한 비정상성 빈도분석을 실시하였다.

환경교육 영상매체 활용 수업이 환경 감수성에 미치는 영향 (The Effect of Using Image Media for Environmental Education on Students' Environmental Sensitivity)

  • 최성봉
    • 한국환경과학회지
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    • 제17권10호
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    • pp.1183-1193
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    • 2008
  • Today, environmental pollution and destruction due to the industrialization of our modem society have been the global issues. Although now we can lead affluent lives through science technologies and economic development, these environmental problems have resulted in striking the harmonious balance between human beings and nature and threatened human lives with abnormal weather caused by the global warming, destruction of the ozone layer, and El Nino phenomenon, acid rain, decrease in species diversity, movement of hazardous materials, and harmful waste increase. We are aware of the importance of environmental education, but in reality, it seems impossible to implement appropriate environmental education on account of our educational climate which exclusively focuses on the entrance examination. However, environmental education is the most ultimate solution for those problems in that only when students understand our environment fully and grow habits to protect it through environmental education, the present environmental problems can be solved and more serious problems that can be resulted in the future can possibly be prevented. Thus, this study has examined the effect of using image media in the environment subject on students' environmental sensitivity. According to the results, it was shown that it had positive effects on 'sensitivity of environment', 'attitudes towards environment', and 'environmental affinitive behaviors'.

도시화가 도시지역 강우변화에 미치는 영향 연구 (A study of urbanization effect to a precipitation pattern in a urban area)

  • 오태석;안재현;문영일;정민수
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2005년도 학술발표회 논문집
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    • pp.894-899
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    • 2005
  • 1970년대 이후, 우리나라는 산업화에 따른 급격한 도시화가 이루어졌다. 본 논문에서는 우리나라의 대표적인 도시인 서울특별시 및 6대 광역시의 1973년부터 2003년까지의 31개년의 강우량 자료를 이용하여 강우량의 변화에 대하여 분석하였다. 또한 강우량의 변화는 도시화 이외에도 엘니뇨 등의 기상 변화와 각종 기상 이변에도 큰 영향을 받으므로 도시 지역과 비교할 수 있는 비도시 지역을 선정하여 도시 지역의 강우량 변화와 비도시지역의 강우량 변화를 비교 분석하였다. 도시 지역과 비도시 지역의 연강우량, 여름 강우량, 지속 시간 1시간 및 24시간 연최대 강우량에 대해 통계적인 분석을 수행하였다. 그 결과, 도시 지역에서의 여름($6\~9$월) 강우량의 증가가 비도시 지역에 비해 두드러졌다.

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