• New & Renewable Energy
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• 제1권1호
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• pp.44-53
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• 2005

To understand general status of the national wind environment and to distinguish potential areas to be developed as a largescale wind farm, a synoptic wind map of the Korean Peninsula is established by processing remote sensing data of the satellite, NASA QuikSCAT which Is deployed for the SeaWinds Project since 1999. According to the validation results obtained by comparing with the measurement data of marine buoys of KMA(Korea Meteorological Administration), the cross-correlation factor Is greatly Improved up to 0.87 by blending the sea-surface dat3 of QuikSCAT with NCEP/NCAR CDAS data. It is found from the established synoptic wind map that the wind speed in winter is prominent temporally and the South Sea shows high energy density up to the wind class 6 spatially. The reason is deduced that the northwest winds through the yellow Sea and the northeast winds through the East Sea derived by the low-pressure developed in Japan are accelerated passing through the Korea Channel and formed high wind energy region in the South Sea; the same trends are confirmed by the statistical analysis of meteorological observation data of KMA.

• 한국해양학회지
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• 제23권3호
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• pp.97-109
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• 1988

The wind stress and the wind-stress curl over the East Sea of Korea are computed from the ship-observed wind data by the FRDA. In order to emphasize the role of the wind in determining the upper-layer structure, rather persistent and strong winds are selected based on the wind-rose data. The monthly averaged wind stresses are comparable in size with the average value over the Japan Sea. But the monthly averaged magnitude of the wind-stress curl is very large compared to the one over the Japan Sea. This may be due to the spatial variation of the wind speeds influenced by the local orography. The wind-driven upper-layer thickness over the East Sea suggests that the site of deep upper layer indeed exists regardless of season but the position does not appear to be fixed. The convergence of warm surface water driven by the wind could be referred as the warm core.

• Proceedings of the KSRS Conference
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• 대한원격탐사학회 1998년도 Proceedings of International Symposium on Remote Sensing
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• pp.225-230
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• 1998

The purpose of this study is to contribute the development of an El Nino prediction model. The objectives of the study are to (1) extract sea surface height data from the TOPEI/Poseidon altimeter, and (2) compare the relations among the sea surface height, sea surface temperature and wind field. NOAA AVHRR Multi-channel data is used for sea surface temperature and wind data is derived from ERS 1, 2 AMI wind scatterometer. The results showed that sea surface height has increased significantly during the El Nino season. The sea surface height is positively related to sea surface temperature and negatively related to zonal wind.

• Journal of the korean society of oceanography
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• 제38권3호
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• pp.135-142
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• 2003

Gas flux across the air-sea interface is often determined by the product of gas transfer velocity k) and the difference of concentrations in water and air. k is primarily controlled by wind stress on the air-sea interface, thus all parameterizations ofk involve wind speed, a rough indicator of wind stress, as one of the independent variables. We attempted to explore the spatial and temporal variations of k in the East (Japan) Sea using a database from Naet al. (1992). Three different parameterizations were employed: those of Liss and Merlivat (1986), Wanninkhof(1992), and Wanninkhofand McGillis (1999). The strong non-linear dependence of k on wind speed in all parameterizations leads us to examine the effect of time resolution, in which the binned wind speeds are averaged, on the estimation ofk. Two time resolutions of 12 hours (short-term) and one month (long-term) were chosen. The mean wind speeds were fed into the given parameterizations, resulting in six different transfer velocities of $CO_2$ ranging from 12 to 32 cm/h. In addition to the threefold difference depending on the choice of parameterization, the long-term average of wind speed results in a value ofk up to 20% higher than the short-term (12 hours) average of wind speed due to the non-Rayleigh wind distribution in the East (Japan) Sea. While it is not known which parameterization is more reliable, this study proposes that the time-averaged wind speed should not be used in areas where non-Ralyleigh wind distribution prevails such as the East (Japan) Sea. The net annual $CO_2$ flux was estimated using the value of k described above and the monthly ${\Delta}fCO_2$ of Oh et al. (1999); this ranges from 0.034 to 0.11 Gt-C/yr.

• Journal of Korean Society for Atmospheric Environment
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• 제21권1호
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• pp.63-72
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• 2005

In order to understand regional wind characteristics and to estimate offshore wind resources, a wind map of the Korean Peninsula was established using remote-sensing data from the satellite, U.S. NASA Quik SCAT which has been deployed for the Sea Winds Project since 1999. According to the linear regression result between the wind map data and in-situ marine-buoy data, the correlation factor was greatly improved up to 0.87 by blending the remote-sensing data of Quik SCAT with U.S. NCEP/NCAR CDAS reanalysis data to eliminate precipitation interference and to increase temporal resolution. It is found from the established wind map that the wind speed in winter is prominent temporally and the South Sea shows spatially high energy density over the wind class 6. The reason is deduced that the north-west winds through the Yellow Sea and the north-east winds through the East Sea derived by the low pressure developed in Japan are accelerated passing through the Korea Channel and formed high wind energy region in the South Sea; the same trends are confirmed from the statistical analysis of the meteorological observation data of KMA.

• Journal of Fisheries and Marine Sciences Education
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• 제26권5호
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• pp.1013-1025
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• 2014

Marine meterological characteristics off the coast in the East Sea between 2006 and 2013 were investigated by comparing the high wind-wave alert and moored-measured significant wave high. Monthly and yearly variations of the high wind-wave alert duration off the coast in the central part of the East Sea are correlated with those of the significant wave height measurement with their minima in June and 2008 and maxima in December and 2012. Both the high wind-wave alert duration and significant wave height increase remarkably during 2010-2013 when compared with during 2006-2009. The remarkable increase, occurring dominantly in December, seems to be related with Arctic oscillation variability. However, the comparisons reveal that only about a half of high wind-wave alerts satisfy the criteria for issuing the high wind-wave alert. To issue the high wind-wave alert, the wind speed at the sea should exceed 14 m/s or the significant wave height should be higher than 3 m. The high wind-wave alerts unsatisfying the significant wave height criteria are issued mainly during spring and summer. These results imply that additional surface buoy moorings in the open basin of the East Sea are necessary for more accurate issue of the high wind-wave alert.

• Journal of Environmental Science International
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• 제14권11호
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• pp.1015-1026
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• 2005

The southeastern coastal area of the Korean peninsula has a complex terrain including an irregular coastline and moderately high mountains. This implies that mesoscale circulations such as mountain-valley breeze and land-sea breeze can play an important role in wind field and ocean forcing. In this study, to improve the accuracy of complex coastal rind field(surface wind and sea surface wind), we carried out the sensitivity experiments based on PBL schemes in PSU/NCAR Mesoscale Model (MM5), which is being used in the operational system at Korea Meteorological Administration. Four widely used PBL parameterization schemes in sensitivity experiments were chosen: Medium-Range Forecast (MRF), High-resolution Blackadar, Eta, and Gayno-Seaman scheme. Thereafter, case(2004. 8. 26 - 8. 27) of weak-gradient flows was simulated, and the time series and the vertical profiles of the simulated wind speed and wind direction were compared with those of hourly surface observations (AWS, BUOY) and QuikSCAT data. In the simulated results, the strength of rind speed of all schemes was overestimated in complex coastal regions, while that of about four different schemes was underestimated in islands and over the sea. Sea surface wind using the Eta scheme showed the highest wind speed over the sea and its distribution was similar to the observational data. Horizontal distribution of the simulated wind direction was very similar to that of real observational data in case of all schemes. Simulated and observed vertical distribution of wind field was also similar under boundary layer(about 1 km), however the simulated wind speed was underestimated in upper layer.

• Journal of Environmental Science International
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• 제14권7호
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• pp.657-667
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• 2005

In this study, we focused on the improvements in the simulation of sea surface wind over the complex coastal area. MM5 model being currently used to predict sea surface wind at Korea Meteorological Administration, was used to verify the accuracy to estimate the local wind field. A case study was performed on clear days with weak wind speed(4 m/s), chosen by the analysis of observations. The model simulations were conducted in the southeastern area of Korea during the selected periods, and observational data such as AWS, buoy and QuikSCAT were used to compare with the calculated wind components to investigate if simulated wind field could follow the tendency of the real atmospheric wind field. Results showed that current operational model, MM5, does not estimate accurately sea surface wind and the wind over the coastal area. The calculated wind speed was overestimated along the complex coastal regions but it was underestimated in islands and over the sea. The calculated diurnal changes of wind direction could not follow well the tendency of the observed wind, especially at nighttime. In order to exceed the limitations, data assimilation with high resolution data and more specificated geographical information is expected as a next best policy to estimate accurately the environment of local marine wind field.

• Journal of the Korean earth science society
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• 제26권3호
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• pp.240-252
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• 2005

The relationships between wave and wind around the Korean Peninsula have been analyzed with the data from the buoys moored at five stations (Dugjug-do, Chilbal-do, Geomoon -do, Geoje-do, Donghae) by Korea Meteorological Administration. Generally, the relationship between wave and wind is the highest at the stations in the West Sea and the lowest at the stations in the South Sea, and the middle at the station in the East Sea. The characteristics shown at each station are as follows. Highest wave is developed at Chilbal-do with strong northwesterly wind in winter because the sea is opened in the wind direction and wave is amplified by shoaling effect. At Chilbal-do, wave directions coincide with wind directions relatively well. On the other hand, waves are not fully developed at Dugjug-do in winter due to limited fetch since the sea is blocked by Hwanghae-do in the northwest direction. The limitation in fetch is more serious at the stations in the South Sea. In the South Sea, the direction of dominant northerly wind is blocked by land so that wave heights are small even with very strong northerly wind. In the South Sea, whatever wind direction is, waves dominantly come in the direction from the East China Sea, which are from the south at Geomoon-do and the southwest at Geoje-do. At these directions, waves are coming even with weak wind. At the station in the East Sea, waves are highly developed due to vast area, but not so high as in Chilbal-do because wind and wave directions do not coincide in many cases. As shown, wind direction is important in the wave development as well as wind speed. The reason is that the fetch is determined by wind direction. In the case of long-lasted wind with fixed direction at Chilbal-do and Dugjug-do, wave directions are well coincident with wind directions and wave heights increase with response time, which is the duration between the highest wind and wave. However, in the case of disagreement between wind and wave directions at the station in the East Sea, wave heights do not increase as highly as at Chilbal-do and Dugjug-do in spite of strong wind and longer response time. The results show us that waves are highly developed with strong wind, long fetch, and long duration, and also show that wave development ratios are different at different stations due to environmental factors such as the direction towards sea or land, bottom topography, and the scales of adjacent seas.

• Journal of Korean Society for Atmospheric Environment
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• 제22권3호
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• pp.309-323
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• 2006

We focus on the improvement in the simulation of sea surface wind over complex coastal area located in the southeastern Korea. In this study, it was carried out sensitivity experiment based on PBL schemes and dynamic frame of MM5 and WRF. Two widely used PBL parameterization schemes were chosen : Medium-Range Forecast (MRF) and Mellor-Yamada-Janjic (MYJ). Thereafter, two cases of sea fog days with weak wind speed and typhoon days with strong wind speed were simulated and analyzed. The result of experiments indicated that wind fold of WRF model was shown more similar distribution with observational data, compared with that of MM5. Simulation of sea surface wind during sea fog days with weak wind speed and typhoon days with strong wind speed were shown similar horizontal distribution with observational data using MYJ and MRF PBL schemes of WRF model, respectively. Horizontal distribution of sea surface wind was more sensitive according to dynamic frame and PBL Schemes of model during sea fog days and typhoon days, respectively.