• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.350-353
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• 2011

전 세계적으로 기후변화로 인한 자연재해가 빈번하게 발생함에 따라 수자원 분야에서 또한 환경의 변화에 대한 정확한 예측이 더욱 요구되고 있다. 국내에서도 이를 위하여 다양한 방법을 통하여 연구가 이루어지고 있으나 본 연구에서 사용된 Common Land Model (CLM)은 국내에서의 실질적인 적용이 아직 부족하다. 이 모형은 Soil-Vegetation-Atmosphere Transfer 모형 중 대표적 모델로 Land Surface Model (LSM), Biosphere-Atmosphere Transfer Scheme (BATS), Chinese Academy of Sciences Institute of Atmospheric Physics LSM의 세 모형이 결합되어 발전하였다. CLM의 강제입력자료로는 위성, 지면모형 등을 기반으로 만들어진 자료를 제공하는 Korea Land Data Assimilation Systme (KLDAS; 한반도지표자료동화체계)의 격자화 된 자료를 사용하여 모형에 강제시켰다. KLDAS는 기존의 Land Data Assimilation System (LDAS)에서 발전한 형태로 동아시아 지역을 대상으로 자료를 제공하고 있으며, 본 연구에서는 이 자료를 사용하여 국내 전반에 걸쳐 격자에 대한 수문 기상학적 인자를 산출하였다.

• Journal of Korean Society on Water Environment
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• v.29 no.2
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• pp.247-258
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• 2013

A grid-based configuration of Land Surface Models (LSMs) coupled with a climate model can be advantageous in impact assessment of climate change for a large scale area. We assessed the applicability of Common Land Model (CoLM) to runoff and land surface temperature (LST) simulations at the domain that encompasses the Nakdong river basin. To establish a high resolution model configuration of a $1km{\times}1km$ grid size, both surface boundary condition and atmospheric inputs from the observed weather data in 2009 were adjusted to the same resolution. The Leaf Area Index (LAI) was collected from MODerate esolution Imaging Spectroradiometer (MODIS) and the downward short wave flux was produced by a nonstationary multi-site weather state model. Compared with the observed runoffs at the stations on Nakdong river, simulated runoffs properly responded to rainfall. The spatial features and the seasonal variations of the domain fairly well were captured in the simulated LSTs as well. The monthly and seasonal trend of LST were described well compared to the observations, however, the monthly averaged simulated LST exceeded the observed up to $2^{\circ}C$ at the 24 stations. From the results of our study, it is shown that high resolution LSMs can be used to evaluate not only quantity but also quality of water resources as it can capture the geographical features of the area of interest and its rainfall-runoff response.

• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.2
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• pp.59-63
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• 2008

The surface runoff is one of the important components for the surface water balance. However, most Land Surface Models(LSMs), coupled to climate models at a large scale for the prediction and prevention of disasters caused by climate changes, simplistically estimate surface runoff from the soil water budget. Ignoring the role of surface flow depth on the infiltration rate causes errors in both surface and subsurface flow calculations. Therefore, for the comprehensive terrestrial water and energy cycle predictions in LSMs, a conjunctive surface-subsurface flow model at a large scale is developed by coupling a 1-D diffusion wave model for surface flow with the 3-D Volume Averaged Soil-moisture Transport(VAST) model for subsurface flow. This paper describes the new conjunctive surface-subsurface flow formulation developed for improvement of the prediction of surface runoff and spatial distribution of soil water by topography, along with basic schemes related to the terrestrial hydrologic system in Common Land Model(CLM), one of the state-of-the-art LSMs.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.535-539
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• 2009

Evapotranspiration (ET) is one of the main factor to understand the hydrologic cycle on land surfaces of entire globe. It accounts for about 65% of precipitation returning to the atmosphere. Accurate estimation of the ET is essential to many applications of water resources management, hydrology, meteorology, climatology, and agriculture. Over the past few decades, there have been extensive efforts to develop and validate a number of ET models. Priestley-Taylor (P-T) and Food and Agriculture Organization Penman-Monteith (P-M) models are generally recognized as simple, but great operational approaches to estimate ET over different land cover types. In this study, we compare/validate different models of increasing complexity, P-T, P-M, and Common Land Model (CLM) in croplands, IA.

• Journal of Korean Society for Atmospheric Environment
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• v.24 no.2
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• pp.259-270
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• 2008

The regional air movement in a coastal area is generated by the different heat capacities of sea and land sides, which is called sea/land breeze. In the west coast area, the local air quality is significantly influenced by this sea/land breeze. In this study, the mathematical model is proposed to estimate the effective area of sea/land breeze. A commercial air model, that is suggested as an alternative air model by USEPA, is introduced to simulate the mechanism of sea/land breeze generation. From this study, it is confirmed that the numerical approach proposed in this study is reliable to predict the effective area of sea breeze in a coastal area. It implies that the current application of common air model needs to be carefully reviewed especially when dealing with a coastal air quality issue. It is also found that the sea breeze in Incheon area has the impact in the range of approximately 24 km in-land side, so-called penetration length.

• Journal of Wetlands Research
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• v.18 no.2
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• pp.166-172
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• 2016

Accurate understanding of land surface is essential to analyze energy exchanges between earth surface and atmosphere. For the quantization of energy fluxes, the various researches about Land Surface Model(LSM) have been progressed. Among the various LSMs, the researches using Common Land Model(CLM) and Variable Infiltration Capacity(VIC) model are performed briskly. The CLM which is advanced LSM can calculate realistic results with few user defined parameters. The VIC model which is also typical LSM is widely used for estimation of energy fluxes and runoff in various fields. In this study, the energy fluxes which are net radiation, sensible heat flux, and latent heat flux were estimated using CLM and VIC model at Southern Sierra-Critical Zone Observatory(SS-CZO) site in California, United States. In case of net radiation and sensible heat flux, both models showed good agreement with observations, however, the CLM showed underestimated patterns of net radiation and sensible heat flux during precipitation period. In case of latent heat flux, the CLM represented better estimation of latent heat flux than VIC model which underestimated the latent heat flux. Through the estimation of energy fluxes and analysis of models' pros and cons, the applicability of CLM and VIC models and need of multi-model application were identified.

• Journal of Korean Society of Rural Planning
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• v.11 no.3 s.28
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• pp.11-17
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• 2005

Land prices reflect not only the uses of land, but the potential uses as well(Plantinga, 2002) so land values can be applied to very effective indices for deciding regional status and growing potential. The purpose of this study is to deduce determinant factors of regional land prices. Principal determinants of regional land prices are analyzed with a hedonic technique and spatial econometric models based on 2001 statistic data of Korea except large cities. The results provide the followings. 1. The spatial effect of rural regions are very little with adjacent regions. 2. The common index of land price is population density and other determinant factors are different depending on land uses.

• Journal of Cadastre & Land InformatiX
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• v.48 no.2
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• pp.51-64
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• 2018

The paper reviews the adoption of ISO 19152, Land Administration Domain Model (LADM) for the enhancement of the current Mongolian cadastral system. It can be said that the current cadastral system is developed for the pure purpose of land registration. There is a need for a comprehensive data model for not only this reason but also reflecting the current problems in the Mongolian cadastral system. The LADM was published by the International Organization for Standardization later in 2012 as an International Standard for modeling cadastral and land administration information for the purpose of providing a common vocabulary(ontology) and efficient system development. This study examined possibilities of adopting the LADM to the cadastral system for Mongolia focused on Land Manager system. Data model of the Land Manager was examined against the corresponding LADM classes and as a result, gaps between each data model have been drawn. Lastly we proposed the LADM-based new data model for Mongolian cadastral system ensuring that the current problems be reflected.

• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.3
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• pp.23-27
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• 2008

The new conjunctive surface-subsurface flow model at a large scale was developed by using a 1-D Diffusion Wave (DW) model for surface flow interacting with the 3-D Volume Averaged Soil-moisture Transport (VAST) model for subsurface flow for the comprehensive terrestrial water and energy predictions in Land Surface Models (LSMs). A selection of numerical implementation schemes is employed for each flow component. The 3-D VAST model is implemented using a time splitting scheme applying an explicit method for lateral flow after a fully implicit method for vertical flow. The 1-D DW model is then solved by MacCormack finite difference scheme. This new conjunctive flow model is substituted for the existing 1-D hydrologic scheme in Common Land Model (CLM), one of the state-of-the-art LSMs. The new conjunctive flow model coupled to CLM is tested for a study domain around the Ohio Valley. The simulation results show that the interaction between surface flow and subsurface flow associated with the flow routing scheme matches the runoff prediction with the observations more closely in the new coupled CLM simulations. This improved terrestrial hydrologic module will be coupled to the Climate extension of the next-generation Weather Research and Forecasting (CWRF) model for advanced regional, continental, and global hydroclimatological studies and the prevention of disasters caused by climate changes.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.3B
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• pp.285-291
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• 2011

Accurate assessment of the water and energy cycles is essential to understand hydrologic, climatologic, and ecological processes. Common Land Model (CLM) is one of the well-developed Soil-Vegetation-Atmosphere Transfer (SVAT) models based on the water and energy balance equation for accurate prediction of hydro-environmental cycles. The CLM can estimate realistic and reliable results using relatively simple parameters. It has been widely used in the world, however in Korea practical applications of the CLM are rare due to lack of information and input data. In this study, the CLM with Korea Flux network (KoFlux) and Kore Land Data Assimilation System (KLDAS) data were individually validated for domestic applications. This study showed that all comparisons between observations and model results from KoFlux and KLDAS had reasonable correlation with determination coefficient of 0.73~1.00 via regression. The results confirmed the applicability of the CLM and the possibility of the KLDAS usage for the region where input data are not existed.