• 제목/요약/키워드: Water cloud model

검색결과 77건 처리시간 0.023초

수도권지역의 지상기반 원격탐사자료를 이용한 지표면 태양에너지 산출 (Estimation of Surface Solar Radiation using Ground-based Remote Sensing Data on the Seoul Metropolitan Area)

  • 지준범;민재식;이한경;채정훈;김상일
    • 한국지구과학회지
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    • 제39권3호
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    • pp.228-240
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    • 2018
  • 2015년부터 최근까지 차세대도시농림융합기상사업단에서는 수도권에 위치한 도시기상 관측소에서 관측된 기상자료(14소), 운고계(2소) 그리고 마이크로웨이브 라디오미터(MWR, 7소) 자료를 이용하여 태양에너지를 산출하였다. 수도권지역에 위치한 운고계에서 관측된 후방산란계수와 MWR에서 추정된 액상물량을 이용하여 구름광학두께와 운량을 산출하였다. 각각의 원격탐사장비에서 산출된 운량을 태양복사모델에 입력하여 지표면에 도달하는 태양에너지를 계산하였다. 추정된 태양에너지를 관측과 비교한 결과, 중랑과 광화문지점에서는 과소추정이 나타났다. 선형회귀분석한 결과 0.8이하의 기울기를 나타냈고 $-20W/m^2$의 음의 편차와 $120W/m^2$의 평방근오차(RMSE)가 나타났다. 그리고 MWR을 이용하여 추정된 태양에너지의 정확도(평균 결정계수$(R^2)=0.8$)와 오차율(평균 $RMSE=110W/m^2$)이 향상되었다. 월별 산출된 운량과 태양에너지는 운고계를 이용하여 산출하였을 때 운량이 0.09 이상 크게 나타났으며 태양에너지가 $50W/m^2$ 이상 낮게 산출되었다. 지점에 따라 차이는 있었으나 대체로 7월과 9월의 RMSE가 $50W/m^2$ 이상 크게 계산되었다. 결과적으로 일누적 태양에너지는 광화문지점에서 가장 높은 상관성이 나타났고($R^2=0.80$, RMSE=2.87 MJ/Day), 구로지점에서 상관성이 가장 낮았다($R^2=0.63$, RMSE=4.77 MJ/Day).

모델 예측변수들을 이용한 집중호우 예측 가능성에 관한 연구 (Studies on the Predictability of Heavy Rainfall Using Prognostic Variables in Numerical Model)

  • 장민;지준범;민재식;이용희;정준석;유철환
    • 대기
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    • 제26권4호
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    • pp.495-508
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    • 2016
  • In order to determine the prediction possibility of heavy rainfall, a variety of analyses was conducted by using three-dimensional data obtained from Korea Local Analysis and Prediction System (KLAPS) re-analysis data. Strong moisture convergence occurring around the time of the heavy rainfall is consistent with the results of previous studies on such continuous production. Heavy rainfall occurred in the cloud system with a thick convective clouds. The moisture convergence, temperature and potential temperature advection showed increase into the heavy rainfall occurrence area. The distribution of integrated liquid water content tended to decrease as rainfall increased and was characterized by accelerated convective instability along with increased buoyant energy. In addition, changes were noted in the various characteristics of instability indices such as K-index (KI), Showalter Stability Index (SSI), and lifted index (LI). The meteorological variables used in the analysis showed clear increases or decreases according to the changes in rainfall amount. These rapid changes as well as the meteorological variables changes are attributed to the surrounding and meteorological conditions. Thus, we verified that heavy rainfall can be predicted according to such increase, decrease, or changes. This study focused on quantitative values and change characteristics of diagnostic variables calculated by using numerical models rather than by focusing on synoptic analysis at the time of the heavy rainfall occurrence, thereby utilizing them as prognostic variables in the study of the predictability of heavy rainfall. These results can contribute to the identification of production and development mechanisms of heavy rainfall and can be used in applied research for prediction of such precipitation. In the analysis of various case studies of heavy rainfall in the future, our study result can be utilized to show the development of the prediction of severe weather.

KIAPS 관측자료 처리시스템에서의 AMSU-A 위성자료 초기 전처리와 편향보정 모듈 개발 (Development of Pre-Processing and Bias Correction Modules for AMSU-A Satellite Data in the KIAPS Observation Processing System)

  • 이시혜;김주혜;강전호;전형욱
    • 대기
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    • 제23권4호
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    • pp.453-470
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    • 2013
  • As a part of the KIAPS Observation Processing System (KOPS), we have developed the modules of satellite radiance data pre-processing and quality control, which include observation operators to interpolate model state variables into radiances in observation space. AMSU-A (Advanced Microwave Sounding Unit-A) level-1d radiance data have been extracted using the BUFR (Binary Universal Form for the Representation of meteorological data) decoder and a first guess has been calculated with RTTOV (Radiative Transfer for TIROS Operational Vertical Sounder) version 10.2. For initial quality checks, the pixels contaminated by large amounts of cloud liquid water, heavy precipitation, and sea ice have been removed. Channels for assimilation, rejection, or monitoring have been respectively selected for different surface types since the errors from the skin temperature are caused by inaccurate surface emissivity. Correcting the bias caused by errors in the instruments and radiative transfer model is crucial in radiance data pre-processing. We have developed bias correction modules in two steps based on 30-day innovation statistics (observed radiance minus background; O-B). The scan bias correction has been calculated individually for each channel, satellite, and scan position. Then a multiple linear regression of the scan-bias-corrected innovations with several predictors has been employed to correct the airmass bias.

An IoT based Green Home Architecture for Green Score Calculation towards Smart Sustainable Cities

  • Kumaran, K. Manikanda;Chinnadurai, M.;Manikandan, S.;Murugan, S. Palani;Elakiya, E.
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제15권7호
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    • pp.2377-2398
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    • 2021
  • In the recent modernized world, utilization of natural resources (renewable & non-renewable) is increasing drastically due to the sophisticated life style of the people. The over-consumption of non-renewable resources causes pollution which leads to global warming. Consequently, government agencies have been taking several initiatives to control the over-consumption of non-renewable natural resources and encourage the production of renewable energy resources. In this regard, we introduce an IoT powered integrated framework called as green home architecture (GHA) for green score calculation based on the usage of natural resources for household purpose. Green score is a credit point (i.e.,10 pts) of a family which can be calculated once in a month based on the utilization of energy, production of renewable energy and pollution caused. The green score can be improved by reducing the consumption of energy, generation of renewable energy and preventing the pollution. The main objective of GHA is to monitor the day-to-day usage of resources and calculate the green score using the proposed green score algorithm. This algorithm gives positive credits for economic consumption of resources and production of renewable energy and also it gives negative credits for pollution caused. Here, we recommend a green score based tax calculation system which gives tax exemption based on the green score value. This direct beneficiary model will appreciate and encourage the citizens to consume fewer natural resources and prevent pollution. Rather than simply giving subsidy, this proposed system allows monitoring the subsidy scheme periodically and encourages the proper working system with tax exemption rewards. Also, our GHA will be used to monitor all the household appliances, vehicles, wind mills, electricity meter, water re-treatment plant, pollution level to read the consumption/production in appropriate units by using the suitable sensors. These values will be stored in mass storage platform like cloud for the calculation of green score and also employed for billing purpose by the government agencies. This integrated platform can replace the manual billing and directly benefits the government.

광합성율과 생물량에 기초한 Sargassum confusum의 생산성 계산 모델 (An Estimation of the Algal Production of Sargassum confusum (Phaeophyta) on the Coast of Ohori, East Sea, Korea, by Mathematical Models Based on Photosynthetic Rates and Biomass Changes)

  • 고철환;조성억
    • 한국해양학회지
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    • 제26권2호
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    • pp.108-116
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    • 1991
  • 동해안 오호리에 서식하는 Sargassum confusum을 대상으로 광합성율과 생물량의 시간에 따른 변화를 조사하여 해조류의 년생산성을 예측하는 모델을 구성하였다. 즉 년생산량 P/SUB yr/를 P/SUB yr/ = .int.P/SUB t/·B/SUB t/dt (이때 P/SUB t/와 B/SUB t/는 주어진 시간에서의 광합성율과 생물량을 나타낸다)의 식을 설정하여 구하 였다. P/SUB t/는 수온과 광량의 함수로 보아 서로 다른 수온과 광도의 조건에서 광합 성을 측정하여 P/SUB t/에 대입하였다. 수온과 Sargassum confusum이 서식하는 수심 3 m를 기준으로 하였다. 모델에 의한 모의 결과는 수온이 일차생산량을 결정하는 가장 중요한 요인임을 보여주었다. 구름을 가정하여 30%의 광량을 무작위로 감소시켰을 때 해조류의 년생산량은 5%감소하였다.

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천리안 위성 자료를 이용한 대류권계면 접힘 난류 탐지 가능성 연구 (Feasibility Study for Detecting the Tropopause Folding Turbulence Using COMS Geostationary Satellite)

  • 김미정;김재환
    • 대기
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    • 제27권2호
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    • pp.119-131
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    • 2017
  • We present and discuss the Tropopause Folding Turbulence Detection (TFTD) algorithm for the Korean Communication, Ocean, Meteorological Satellite (COMS) which is originally developed for the Tropopause Folding Turbulence Product (TFTP) from the Geostationary Operational Environmental Satellite (GOES)-R. The TFTD algorithm assumes that the tropopause folding is linked to the Clear Air Turbulence (CAT), and thereby the tropopause folding areas are detected from the rapid spatial gradients of the upper tropospheric specific humidity. The Layer Averaged Specific Humidity (LASH) is used to represent the upper tropospheric specific humidity calculated using COMS $6.7{\mu}m$ water vapor channel and ERA-interim reanalysis temperature at 300, 400, and 500 hPa. The comparison of LASH with the numerical model specific humidity shows a strong negative correlation of 80% or more. We apply the single threshold, which is determined from sensitivity analysis, for cloud-clearing to overcome strong gradient of LASH at the edge of clouds. The tropopause break lines are detected from the location of strong LASH-gradient using the Canny edge detection based on the image processing technique. The tropopause folding area is defined by expanding the break lines by 2-degree positive gradient direction. The validations of COMS TFTD is performed with Pilot Reports (PIREPs) filtered out Convective Induced Turbulence (CIT) from Dec 2013 to Nov 2014 over the South Korea. The score test shows 0.49 PODy (Probability of Detection 'Yes') and 0.64 PODn (Probability of Detection 'No'). Low POD results from various kinds of CAT reported from PIREPs and the characteristics of high sensitivity in edge detection algorithm.

위성자료를 이용한 몽골의 일사량 분포 특성 (The Character of Distribution of Solar Radiation in Mongolia based on Meteorological Satellite Data)

  • 지준범;전상희;최영진;이승우;박영산;이규태
    • 한국지구과학회지
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    • 제33권2호
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    • pp.139-147
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    • 2012
  • 몽골의 태양-기상자원지도는 위성자료 및 재분석 자료를 이용하여 개발되었다. 태양복사량은 단층 태양복사모델을 이용하였으며 입력자료는 SRTM, MODIS, OMI, MTSAT-1R 등의 위성관측자료와 전구모델의 재분석자료를 이용하였다. 계산된 결과는 NCEP/NCAR 재분석 DSWRF 자료를 이용하여 계산된 일사량을 검증하였다. 몽골은 서부의 산악지역과 중남부의 사막 및 반사막지대로 이루어져 있으며 대륙 내부에 위치하여 강수량이 적고 맑은 날이 많아 동일 위도상의 다른 지역과 비교하여 높은 일사량이 나타난다. 서부 산악지역은 고도가 높아 태양에너지가 많이 도달되는 곳임에도 불구하고 일사량이 낮게 나타난다. 그 이유는 산악지역에 존재하는 연중 적설이 위성자료의 구름탐지 알고리즘에서 구름으로 오탐지 되기 때문이다. 따라서 청천지수뿐만 아니라 일사량 또한 낮게 계산된다. 남부지역은 상대적으로 높은 가강수량과 에어로솔 광학두께가 나타났으나 다른 지역에 비해 위도가 낮고 청천지수가 높아 일사량이 높게 나타나는 것으로 분석된다. 계산된 월 누적 일사량은 547.59 MJ로써 전 지점에서 약 2.89 MJ로 높게 계산되었으며 상관성은 0.99였고 평방근오차(Root Mean Square Error; RMSE)는 6.17 MJ 이었다. 월별 통계 값을 계산하였을 때 상관성이 가장 높은 월은 10월로 0.94였고 3월은 0.62로 가장 낮게 나타났다.