• Title/Summary/Keyword: CERES

Search Result 61, Processing Time 0.023 seconds

A Sensitivity Analysis of Accuracy for COMS Outgoing Longwave Radiation Product

  • Kim, Hyunji;Han, Kyung-Soo;Lee, Chang Suk;Shin, Inchul
    • Korean Journal of Remote Sensing
    • /
    • v.31 no.1
    • /
    • pp.39-46
    • /
    • 2015
  • Outgoing Longwave Radiation (OLR) is emitted energy from the Earth that is an important indicator of cooling effect in global scale and meteorological events in regional scale. Satellite-driven OLR products have its advantages overcoming spatially limited representation. The Korean geostationary satellite, Communication, Ocean and Meteorological Satellite (COMS), has been producing OLR product in accordance with its own algorithm since Apr. 2011. This study introduces Spatio-Temporally Equalized Match-up (STEM) approach to evaluate the COMS OLR products. We have tested a number of cases of thresholds set by standard deviations of a subpixel $10.8{\mu}m$ to find optimal representation of OLR in the selective match-up. Each case was then validated with broadband reference data, Clouds and the Earth's Radiant Energy System (CERES). We found that selective STEM approach was useful to validate OLR product especially its distribution in homogeneous grids.

Comparative Analysis of Algorithm for Calculation of Absorbed Shortwave Radiation at Surface Using Satellite Date (위성 자료를 이용한 지표면 흡수단파복사 산출 알고리즘들의 비교 분석)

  • Park, Hye-In;Lee, Kyu-Tae;Zo, Il-Sung;Kim, Bu-Yo
    • Korean Journal of Remote Sensing
    • /
    • v.34 no.6_1
    • /
    • pp.925-939
    • /
    • 2018
  • Absorbed shortwave radiation at the surface is an important component of energy analysis among the atmosphere, land, and ocean. In this study, the absorbed shortwave radiation was calculated using a radiation model and surface broadband albedo data for application to Geostationary Earth Orbit Korea Multi-Purpose SATellite (GEO-KOMPSAT-2A; GK-2A). And the results (GWNU algorithm) were compared with CERES data and calculation results using pyranometer and MODIS (Moderate Resolution Imaging Spectroradiometer) data to be selected as the reference absorbed shortwave radiation. This GWNU algorithm was also compared with the physical and statistical algorithms of GOSE-R ABI and two algorithms (Li et al., 1993; Kim and Jeong, 2016) using regression equation. As a result, the absorbed shortwave radiation calculated by GWNU algorithm was more accurate than the values calculated by the other algorithms. However, if the problem about computing time and accuracy of albedo data arise when absorbed shortwave radiation is calculated by GWNU algorithm, then the empirical algorithms explained above should be used with GWNU algorithm.

Comparison of the Weather Station Networks Used for the Estimation of the Cultivar Parameters of the CERES-Rice Model in Korea (CERES-Rice 모형의 품종 모수 추정을 위한 국내 기상관측망 비교)

  • Hyun, Shinwoo;Kim, Tae Kyung;Kim, Kwang Soo
    • Korean Journal of Agricultural and Forest Meteorology
    • /
    • v.23 no.2
    • /
    • pp.122-133
    • /
    • 2021
  • Cultivar parameter calibration can be affected by the reliability of the input data to a crop growth model. In South Korea, two sets of weather stations, which are included in the automated synoptic observing system (ASOS) or the automatic weather system (AWS), are available for preparation of the weather input data. The objectives of this study were to estimate the cultivar parameter using those sets of weather data and to compare the uncertainty of these parameters. The cultivar parameters of CERES-Rice model for Shindongjin cultivar was calibrated using the weather data measured at the weather stations included in either ASO S or AWS. The observation data of crop growth and management at the experiment farms were retrieved from the report of new cultivar development and research published by Rural Development Administration. The weather stations were chosen to be the nearest neighbor to the experiment farms where crop data were collected. The Generalized Likelihood Uncertainty Estimation (GLUE) method was used to calibrate the cultivar parameters for 100 times, which resulted in the distribution of parameter values. O n average, the errors of the heading date decreased by one day when the weather input data were obtained from the weather stations included in AWS compared with ASO S. In particular, reduction of the estimation error was observed even when the distance between the experiment farm and the ASOS stations was about 15 km. These results suggest that the use of the AWS stations would improve the reliability and applicability of the crop growth models for decision support as well as parameter calibration.

Regression Diagnostic Using Residual Plots

  • Oh, Kwang-Sik
    • Communications for Statistical Applications and Methods
    • /
    • v.8 no.2
    • /
    • pp.311-317
    • /
    • 2001
  • It is necessary to check the linearity of selected covariates in regression diagnostics. There are various graphical methods using residual plots such as partial residual plots, augmented partial residual plots and combining conditional expectation and residual plots. In this paper, we propose the modified pseudolikelihood ratio test statistics based on these residual plots to test linearity of selected covariate. These test statistics which measure the distance between the nonparametric and parametric models are derived as a ratio of quadratic forms. The approximate distribution of these statistics is calculated numerically by using three moments. The power comparison of these statistics is given.

  • PDF

Using spatial data and crop growth modeling to predict performance of South Korean rice varieties grown in western coastal plains in North Korea II. Genetic coefficients of South Korean cultivars for CERES-Rice (공간정보와 생육모의에 의한 남한 벼 품종의 북한 서부지대 적응성 예측 II. 남한 벼 품종의 모수 추정)

  • 김재영;한상욱;김희동;김영호
    • Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
    • /
    • 2002.11a
    • /
    • pp.69-72
    • /
    • 2002
  • 작물생육모형은 작물의 광합성과정 등 주요 생리과정을 정량적으로 연구하기 위해 30여 년 전부터 소개되기 시작하였다. 다양한 환경조건 하에서 생장 및 발육의 종합적인 모의가 가능한 정도로 발전한 최근에는 주요 식량작물에 대해 실용수준의 모형들이 개발되어 다양한 용도로 쓰이고 있다.(중략)

  • PDF

Using spatial data and crop growth modeling to predict performance of South Korean rice varieties grown in western coastal plains in North Korea III. Evaluation of site-specific adaptability of South Korean cultivars (공간정보와 생육모의에 의한 남한 벼 품종의 북한 서부지대 적응성 예측 III. 품종별 지역적응성 평가)

  • 한상욱;김희동;김영호;정유란
    • Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
    • /
    • 2002.11a
    • /
    • pp.73-76
    • /
    • 2002
  • 남한 벼 품종들의 북한 서부지역 적응성을 평가하고자 11개 품종의 유전적 특성을 갖도록 모수가 조정된 벼 생육모형 CERES-rice를, 선행연구에 의해 생성된 496개 재배구역별 일기상 자료를 이용하여 30년 간씩 구동함으로써 각 재배구역의 품종별 기후학적 적응성을 평가하였다.(중략)

  • PDF

Government, Industry and Public Management of the Seas in the 21st Century (21세기의 환경관리 공조체제를 위한 당면과제와 대응책)

  • 윤영철
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.1 no.2
    • /
    • pp.133-138
    • /
    • 1995
  • It is argued that conventional behavior of government, industry, and the public in managing the seas is dysfunctional and must change. Industry manipulation of government regulatory processes, the public complacency that allows it, and its consequences are discussed. Resolving this problem will reqire industry to embrace a code of environmental ideals such as the Coalition for Environmentally Responsible Economies(CERES) principles. A new emerging 'corporate environmentalism' is discussed.

  • PDF

Dynamic Residual Plots for Linear Combinations of Explanatory Variables

  • Son, Seo-Han
    • Communications for Statistical Applications and Methods
    • /
    • v.11 no.3
    • /
    • pp.529-537
    • /
    • 2004
  • This article concerns dynamic graphical methods for visualizing a curvature in regression problem in which some predictors enter nonlinearly. A sequence of augmented partial residual plot or partial residual plot updated by the change of linear combination of two predictors are constructed. Examples demonstrate that the suggested methods can be used to reduce the dimension of explanatory variables as well as to capture a curvature.