• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.2B
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• pp.103-111
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• 2012

This study is to analyze the spatio-temporal trend of snowfall using 30 years (1980-2010) data for 5 selected heavy snowfall areas (Ulleungdo (a), Northeastern Region (b), Western Taebaek Range Inland Region (c), Northwestern Sobaek Range Inland Region (d) and Southern Coastal Region (e)). The snow depth and snowfall frequency during 30 years showed some decreasing trend in parts of c and d. From the spatial comparison for 2 periods between 1980-2000 (A) and 1990-2010 (B), we could identified that the frequency of advisory for heavy snowfall from A to B decreased in c and d showing clear bounds for some areas in period B. For the average snow depth from A to B, the area d decreased while the area b increased with enlarging the areal range.

• Atmosphere
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• v.18 no.4
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• pp.367-386
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• 2008

The Weather Research and Forecasting (WRF) model was designed to identify the role of the Taebaek Mountains in the occurrence of heavy snowfall in Yeongdong area with a strong northeast wind on January 20-21, 2008. To this end, in addition to the control simulation with the realistic distribution of the Taebaek Mountains, a sensitivity experiment that removed the orography over the Taebaek Mountains was performed. The control simulation results showed that the resulting wind field and precipitation distribution were similar to what were observed. Results from the sensitivity experiment clearly demonstrates the presence of orographic lifting on the windward slope of the mountains. It is concluded that the altitude of the Taebaek Mountains is the main controlling factor in determining the distribution and amount of precipitation in the Yeongdong area for the case of heavy snowfall in January 2008.

• Atmosphere
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• v.16 no.3
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• pp.247-257
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• 2006

The Yeong-dong heavy snowfall forecast supporting system has been developed during the last several years. In order to construct the conceptual model, we have examined the characteristics of heavy snowfalls in the Yeong-dong region classified into three precipitation patterns. This system is divided into two parts: forecast and observation. The main purpose of the forecast part is to produce value-added data and to display the geography based features reprocessing the numerical model results associated with a heavy snowfall. The forecast part consists of four submenus: synoptic fields, regional fields, precipitation and snowfall, and verification. Each offers guidance tips and data related with the prediction of heavy snowfalls, which helps weather forecasters understand better their meteorological conditions. The observation portion shows data of wind profiler and snow monitoring for application to nowcasting. The heavy snowfall forecast supporting system was applied and tested to the heavy snowfall event on 28 February 2006. In the beginning stage, this event showed the characteristics of warm precipitation pattern in the wind and surface pressure fields. However, we expected later on the weak warm precipitation pattern because the center of low pressure passing through the Straits of Korea was becoming weak. It was appeared that Gangwon Short Range Prediction System simulated a small amount of precipitation in the Yeong-dong region and this result generally agrees with the observations.

• Atmosphere
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• v.18 no.4
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• pp.339-354
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• 2008

A numerical simulation of a heavy snowfall event that occurred 13 January 2008 along the Yeongdong coastal area, was performed using WRF (Weather Research and Forecasting) in order to reveal mesoscale structures and to construct a conceptual model showing the meteorological background that caused the large difference in snowfall amounts between the Yeongdong mountain area and the Yeongdong coastal area. The simulation results matched well with various observations such as corresponding 12h-accumulated observed precipitation, surface wind obscrvation, radar echoes, and satellite infrared images. The simulation and the observations showed that the scale of the event was of meso - $\beta$ and meso - $\gamma$ scale. The simulation represented well the mesoscale process causing the large difference in snowfall amounts in the two areas. First, wind flow was kept, to a certain extent, from crossing the mountains due to the blocking effect of the low Froude number (~1). The northeast flow over the adjaccnt sea tumcd northwest as it approachcd the mountains, where it was trapped, allowing so-called cold air damming. Second, a strong convergence area formed where the cold northwest flow along the Yeongdong coastal area and the relatively warm and moist northeast flow advecting toward the coast met, supporting the fonllation of a coastal front. Thus, the vertical motion was strongest over the front located near the coast, leading to the heavy snowfall there rather than in the remote mountain area.

• Journal of Environmental Science International
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• v.28 no.9
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• pp.765-784
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• 2019

The synoptic structural characteristics associated with heavy snowfall (Bukgangneung: 31.3 cm) that occurred in the Yeongdong area on 20 January 2017 was investigated using surface and upper-level weather charts, European Centre for Medium-Range Weather Forecasts (ECMWF) reanalysis data, radiosonde data, and Moderate Resolution Imaging Spectroradiometer (MODIS) cloud product. The cold dome and warm trough of approximately 500 hPa appeared with tropopause folding. As a result, cold and dry air penetrated into the middle and upper levels. At this time, the enhanced cyclonic potential vorticity caused strong baroclinicity, resulting in the sudden development of low pressure at the surface. Under the synoptic structure, localized heavy snowfall occurred in the Yeongdong area within a short time. These results can be confirmed from the vertical analysis of radiosonde data and the characteristics of the MODIS cloud product.

• Journal of the Korean Society of Safety
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• v.34 no.2
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• pp.34-39
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• 2019

Vinyl house consists of main rafter, lateral member, clamps and polyethylene film. Many vinyl houses are used in the countryside to grow vegetables. These vinyl houses have occasionally been collapsed due to heavy snowfall in winter. Many farmers get a lot of economical damages, if vinyl houses are collapsed. So it is most important to built a safe vinyl house that can withstand heavy snowfall. In this study, a structural analysis was performed on three types of vinyl houses(07-single-01, 10-single-04, 12-single-01). In addition, the structural analysis of the three types of vinyl houses provided axial forces, flexural moment, and combined stress. For these three types of vinyl houses, structural safety was reviewed by obtaining the combined stress ratio by the strength design method. This structural review showed that the specifications for the vinyl house proposed in the design are not safe. Especially, the result of increasing the design snow load by 15 percent and 30 percent showed that the vinyl house structure constructed as a standard for vinyl house was a more dangerous structure. Therefore, it is necessary to revise regulations such as increasing the thickness of rafters or widening the gap in order to make vinyl houses structurally safe for heavy snowfall in the future, and to devise diverse methods to make vinyl houses that are structurally safe.

• Atmosphere
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• v.19 no.1
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• pp.9-36
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• 2009

Two heavy snowfall events occurred in Yeongnam and Yeongdong regions of the Korean Peninsula during the period from 4 to 6 March 2005 are analyzed. The events were developed by two different meso-scale snow clouds associated with an extratropical low passing over the Western Pacific. Based on synoptic data, GOES-9 satellite images, and precipitation amount data, the events were named as Sokcho and Busan cases, respectively. We analyzed the development mechanism of the events using meterological variables from the NCEP(National Centers for Environmental Prediction) /NCAR(National Centers for Atmospheric Research) reanalysis data such as potential vorticity(PV), divergence, tropopause undulation, static stability, and meridional wind circulation. The present analyses show that in the case of Sokcho, the cyclonic circulation in the lower atmosphere in the strong baroclinic region induced the cyclonic circulation in the upper atmosphere. The cyclonic circulation in the lower and upper atmosphere caused a heavy snowfall in the Sokcho region. In the case of Busan, the strong cyclonic circulation in the upper atmosphere was initiated by the stratospheric air intrusion with the high positive PV into the troposphere during the tropopause folding. The upper strong cyclonic circulation enhanced the cyclonic circulation in the lower disturbed atmosphere due to the extratropical low. This lower cyclonic circulation in turn, intensified the upper cyclonic circulation, that caused a heavy snowfall in the Busan region.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.30 no.1
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• pp.97-104
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• 2012

In this paper, the GPS precipitable water vapor was retrieved by estimating of GPS signal delay in the troposphere during the progress of heavy snowfall on the Gangwon Province, 2011. For this period, the time series analysis between GPS precipitable water vapor and fresh snow depth was accomplished. The time series and the comparison with the GPS precipitable water vapor and the fresh snow depth indicates that the temporal change of two variations is closely related to the progress of the heavy snowfall. Also, the periodicity of GPS precipitable water vapor using the wavelet transform method was showed a similar cycle of saturated water vapor pressure as the limitation of this study span. The result shows that the decrement of GPS precipitable water vapor was conflicted with the increment of fresh snow depth at two sites, Gangneung and Uljin. The correlation between the GPS precipitable water vapor and the saturated water vapor pressure for the event was showed a positive correlation, compare with the non-heavy snowfall periods.

• Journal of Environmental Science International
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• v.23 no.8
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• pp.1481-1493
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• 2014

In order to understand the relation between the distribution of sea surface temperature and heavy snowfall over western coast of the Korean peninsula, several numerical assessments were carried out. Numerical model used in this study is WRF, and sea surface temperature data were FNL(National Center for Environment Prediction-Final operational global analysis), RTG(Real Time Global analysis), and OSTIA(Operational Sea Surface Temperature and Sea Ice Analysis). There were produced on the basis of remote sensing data, such as a variety of satellite and in situ observation. The analysis focused on the heavy snowfall over Honam districts for 2 days from 29 December 2010. In comparison with RTG and OSTIA SST data, sensible and latent heat fluexes estimated by numerical simulation with FNL data were higher than those with RTG and OSTIA SST data, due to higher sea surface temperature of FNL. General distribution of RTG and OSTIA SST showed similar, however, fine spatial differences appear in near western coast of the peninsula. Estimated snow fall amount with OSTIA SST was occurred far from the western coast because of higher SST over sea far from coast than that near coast. On the other hand, snowfall amount near coast is larger than that over distance sea in simulation with RTG SST. The difference of snowfall amount between numerical assessment with RTG and OSTIA is induced from the fine difference of SST spatial distributions over the Yellow sea. So, the prediction accuracy of snowfall amount is strongly associated with the SST distribution not only over near coast but also over far from the western coast of the Korean peninsula.

• Journal of the Korean Geographical Society
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• v.43 no.6
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• pp.843-857
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• 2008

This study analyzed distribution of natural disaster and trend of related climatic elements in mountainous region of Gangwon-do. In mountainous region of Gangwon-do, there have been 27 natural disasters of which heavy rainfall have the leading cause for the last 5 years(16 times in 2003-2007). It has been 9 natural disasters in Jinbu-myeon Pyeongchang-gun, the most frequent area. The mountainous region has been larger natural damage than its surrounding regions and there has been more damage at higher altitudes. While the heavy rainfall have caused damage over the northwest of mountains, most typhoons have damaged southern part of mountains. Most mountainous region suffers from strong wind but damage by snow is small. In mountainous region of Gangwon-do, annual precipitation, intensity of precipitation and heavy rainfall days have been increasing since 2000 and this tendency is significant in its intensity. However, annual snowfall, snowfall days and heavy snowfall days have been clearly decreasing since 2000. In case heavy rainfall accompanies strong wind, the damages are larger in mountainous region of Gangwon-do. Therefore it is important to be prepared for heavy rainfall and strong wind.