Sanghoon Park

Abstract. Atmospheric dynamical cores are a fundamental component of global atmospheric modeling systems and are responsible for capturing the dynamical behavior of the Earth's atmosphere via numerical integration of the Navier–Stokes equations. These systems have existed in one form or another for over half of a century, with the earliest discretizations having now evolved into a complex ecosystem of algorithms and computational strategies. In essence, no two dynamical cores are alike, and thei

Abstract Idealized normal-mode baroclinic wave simulations are conducted to examine the impact of continuous mesh refinement compared with stepwise changes in resolution using nested grids. The nested-grid results are produced using the Advanced Research Weather Research and Forecasting (WRF-ARW) Model, hereafter ARW, and the continuous refinement results are produced using the atmospheric component of the Model for Prediction Across Scales-Atmosphere (MPAS-A). For the nested domain simulations

Abstract The hydrostatic and nonhydrostatic atmospheric solvers within the Model for Prediction Across Scales (MPAS) are tested using an extension of Jablonowski and Williamson baroclinic wave test case that includes moisture. This study uses the dry test case to verify the correctness of the solver formulation and coding by comparing results from the two different MPAS solvers and from the global version of the Advanced Research Weather Research and Forecasting Model (ARW-WRF). A normal mode in

Abstract Although a terrain-following vertical coordinate is well suited for the application of surface boundary conditions, it is well known that the influences of the terrain on the coordinate surfaces can contribute to increase numerical errors, particularly over steep topography. To reduce these errors, a hybrid sigma–pressure coordinate is formulated in the Weather Research and Forecasting (WRF) Model, and its effects are illustrated for both an idealized test case and a real-data forecast

Abstract. This paper describes the splitting supercell idealized test case used in the 2016 Dynamical Core Model Intercomparison Project (DCMIP2016). These storms are useful test beds for global atmospheric models because the horizontal scale of convective plumes is O(1 km), emphasizing non-hydrostatic dynamics. The test case simulates a supercell on a reduced-radius sphere with nominal resolutions ranging from 4 to 0.5 km and is based on the work of Klemp et al. (2015). Models are initialized w

Abstract. An idealized baroclinic instability case is simulated using a ∼ 10 km resolution global model to investigate the characteristics of gravity waves generated in the baroclinic life cycle. Three groups of gravity waves appear around the high-latitude surface trough at the mature stage of the baroclinic wave. They have horizontal and vertical wavelengths of 40–400 and 2.9–9.8 km, respectively, in the upper troposphere. The two-dimensional phase-velocity spectrum of the waves is arc shaped

Abstract On 2 November 2015, unrealistically large areas of light‐or‐stronger turbulence were predicted by the WRF‐RAP (Weather Research and Forecast Rapid Refresh)‐based operational turbulence forecast system over the western U.S. mountainous regions, which were not supported by available observations. These areas are reduced by applying additional terrain averaging, which damps out the unphysical components of small‐scale (~2Δ x ) energy aloft induced by unfiltered topography in the initializa

PURPOSE: The purpose of this study was to compare the removal torques of a chemically modified SLActive implant and a blasted, laser-treated (BLT) implant, which were soaked in saline for 2 weeks after their surface modifications. The removal torques of the two implants were measured 4 weeks after their implantation into the bone defect area in rabbit tibias with concentrated growth factor (CGF) application. MATERIALS AND METHODS: To make artificial bone defects in the cortical layers of both ti

In this study, we investigated the synoptic features of the August 26–27, 2018 heavy rainfall episode, which was accompanied by a quasi-stationary front over the Korean peninsula, as well as its relationship with the climatological characteristics of the Western Pacific Subtropical High (WPSH), using reanalysis and observational data. Through a case study, we analyzed the synoptic environment and frontal structure of the heavy rainfall event by comparing it with a heavy rainfall event associated

본 논문에서는 사회기반시설 자산관리 프로세스와 운영기법을 담은 표준적인 매뉴얼 프레임워크를 제시하여 발주청이 자체적으로 가감하여 매뉴얼을 구성·활용할 수 있도록 사회기반시설 자산관리 매뉴얼의 프레임워크를 제시하였다. 이를 위해 국내 사회기반시설 자산관리 환경·현황 분석을 통해 자산관리 도입의 당위성을 살펴보고, 정부와 발주청의 자산관리 매뉴얼 현황과 미비점을 점검하였고, 호주, 영국, 미국의 선진국 사회기반시설 자산관리 매뉴얼 현황 및 체계를 파악하고 각국의 자산관리 매뉴얼의 특징을 분석·비교하여 한국의 사회기반시설 자산관리 매뉴얼에서 참고할 수 있도록 매뉴얼 구성방향을 도출하였다. 이를 통해 도출된 국내외 사회기반시설 자산관리 매뉴얼 구성방향을 통해 외국의 자산관리 매뉴얼의 특징을 반영하는 범용성, 자산관리 숙련도별 조직별 차등 적용가능성, 사용자의 편의성, 순환적 프로세스를 고려하여 발주청이 활용할 수 있는 사회기반시설 자산관리 매뉴얼의 프레임워크를 제시하였다.

Abstract New high-order time-integration schemes for fully elastic models are presented. The new schemes, formulated using the Richardson extrapolation that employs leapfrog-type schemes, can give a good performance for linear model problems and ensure overall stability when they are combined with a forward–backward scheme for fast waves. The new and existing schemes show differences in the order of accuracy. Thus, they can be useful for investigating the impacts of time-integration scheme accur

Abstract Convectively coupled Kelvin waves (CCKWs) significantly influence tropical rainfall variability; however, accurately simulating these waves remains a challenge in atmospheric modeling. Cumulus parameterization is a critical element in model‐generated CCKW activity among the various factors. This study investigated the impact of cumulus parameterization on CCKW simulation by analyzing the coupling mechanism between tropical convection and Kelvin waves, expanding on the stratiform instabi