• Korean Journal of Remote Sensing
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• v.39 no.3
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• pp.355-361
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• 2023

Temperature of the Earth's surface is a crucial physical variable in understanding weather and atmospheric dynamics and in coping with extreme heat events that have a great impact on living organismsincluding humans. Thermalsensors on satellites have been a useful meansfor acquiring surface temperature information for wide areas on the globe, and thus characterization of its estimation uncertainty is of central importance for the utilization of the data. Among various factors that affect the estimation, the uncertainty caused by the algorithm itself has not been tested for the atmospheric environment of Korean vicinity. Thisstudy derivesthe uncertainty of the single-channel algorithm under the local atmospheric and oceanic conditions by using reanalysis data and buoy temperature data collected around Korea. Atmospheric profiles were retrieved from two types of reanalysis data, the fifth generation of European Centre for Medium-Range Weather Forecasts reanalysis of the global climate and weather (ERA5) and Modern-Era Retrospective analysis for Research and Applications-2 (MERRA-2) to investigate the effect of reanalysis data. MODerate resolution atmospheric TRANsmission (MODTRAN) was used as a radiative transfer code for simulating top of atmosphere radiance and the atmospheric correction for the temperature estimation. Water temperatures used for MODTRAN simulations and uncertainty estimation for the single-channel algorithm were obtained from marine weather buoyslocated in seas around the Korean Peninsula. Experiment results showed that the uncertainty of the algorithm varies by the water vapor contents in the atmosphere and is around 0.35K in the driest atmosphere and 0.46K in overall, regardless of the reanalysis data type. The uncertainty increased roughly in a linear manner as total precipitable water increased.

• 한국해양학회지
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• v.20 no.1
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• pp.50-55
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• 1985

With the serial observation data of the Fisheries Research and Development Agency in Korea and Japan Meteorological Agency from 1969 to 1974, the geostrophic current and volume transport were calculated in the Korea Strait and in the middle of the East Sea (Japan Sea), in order to compare the total volume transport in summer and winter seasons. The results are as follows. The annual mean of the net volume transport of the Korea Strait is 0.19${\times}$10$\^$6/m$\^$3/sec in winter season and 1.33${\times}$10$\^$6/m$\^$3/sec in summer season. The transport through the western and eastern channel of the Korea Srait is almost same in winter season, but the transport of the western channel is much larger than that of the eastern channel in summer season. The annual mean of the net volume transport of the middle section of the East Sea (Japan Sea) is 2.61${\times}$10$\^$6/m$\^$3/sec in winter season and 2.41${\times}$10$\^$6/m$\^$3/sec in summer season. Therefore the transorts are almost same in both seasons. Comparing the transports of the two sections, the transport through the middle section of the East Sea is 13.7 times as large as that of the Korea Strait in winter season and 1.8 times in summer season.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.11 no.1
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• pp.1-7
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• 1975

The physical oceanographic investigations in Kwang Yang Bay, were carried out for seven times from May 1974 to May 1975. The results of this survey show that the salinity of the bay water is generally lower than that of the adjacent sea water, and mean surface salt ni ty in March and July were 20.8-25.2\ulcorner and 31. 8-32. 5\ulcorner. The month with the minimum surface water temperature was January with $2.5~5.2^{\circ}C:$ the maximum monthly value was $ 23.8-24.2 ^{\circ} C$ in September. The surface water temperature were related to the heat budget at the sea surface in the bay water, the degree of relationship was good. The mean vertical stability in the bay water(0-10m)were 297XI0^{-6} in July and -IXto^{-6} in January. The computed vertical stability indicate that the vertical mixing could move down to the depths of 15m during late autumn and winter, but the rest of season hardly take place to the depths of tom.

• Spatial Information Research
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• v.22 no.5
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• pp.19-26
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• 2014

International attention on the Northern Sea Route has been increased as the decreased sea-ice extents in Northern Sea raise the possibility to develop new sea routes and natural resources. However, to protect ships' safety and pristine environments in polar waters, International Maritime Organization(IMO) has been developing the Polar Code to regulate polar shipping. The marine navigation supporting system is essential for ships traveling long distance in the Northern Sea as they are affected by ocean weather and sea-ice. Therefore, to cope with the IMO Polar Code, this research proposes the functional requirements to develop the marine navigation supporting system for the Northern Sea Route. The functional requirements derived from the IMO Polar code consist of arctic voyage risk map, arctic voyage planning and MSI(Marine Safety Information) methods, based on which the navigation supporting system is able to provide dynamic and safe-economical sea route service using the sea-ice observation and prediction technologies. Also, a requirement of the system application is derived to apply the marine navigation supporting system for authorizing ships operating in the Northern Sea. To reflect the proposed system in the Polar Code, continual international exchange and policy proposals are necessary along with the development of sea-ice observation and prediction technologies.

• Korean Journal of Remote Sensing
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• v.14 no.1
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• pp.37-52
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• 1998

The NSCAT(NASA Scatterometer) carried by the japanese Advanced Earth Observing Satellite(ADEOS) was the first high resolution(25 km) device for the direct wind measurement over the ocean. Even it was ceased to operate in lune of 1977 because of the power failure, it gave the first opportunity to the marine meteorologists to study the direct measured ocean wind during its 9 months of operation, especially around Korea. This study is to show monthly mean ocean wind and wind stress curl fields around Korea from January, 1997 to June, 1997. Mean ocean winds in January are predominantly northwesterly and the strongest wind(12 m/s) is found near Vladivostok. The winds in the western East Sea are strongly inf1uenced by the mountain range in Korea and these topographically influenced winds make about five times larger wind stress curl fields than previous estimates based on the weather maps. The calculation of Sverdrup transport in the East Sea shows the possibility of the directional change of the East Korean Cold Current from southward to northward direction caused by the winter wind. The downwelling area near North Korea has maximum estimated speed of 45 m in january and this wind induced downwelling makes good condition for the formation of Intermediate East Sea Water together with vigorous mixing by the strong wind.

• Journal of Korean Society for Atmospheric Environment
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• v.10 no.E
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• pp.332-342
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• 1994

Hierarchical cluster and factor analyses were used to identify various influences on free tropospheric air samples at Mauna Loa Observatory in Hawaii during MLOPEX. The cluster analysis separated thirteen chemical and meteorological variables into three characteristic groups (1)clean air, (2)anthropogenically influenced air, (3)marine and volcanic influenced air. The cluster analysis results compared well with those of factor analysis. Six independent components were identified in factor analysis. We have related these components to (1)volcano influenced air, (2)stratosphere-like air, (3)boundary-layer air with recent anthropogenic influence, (4)photochemical haze, (5)marine boundary- layer air, and (6)modified marine tropospheric air. Excluding local influence, we could calculate the nighttime free tropospheric values for $O_3$(41$\pm$10 ppbv), HN $O_3$(94$\pm$45 pptv), N $O_3$$^{[-10]}$ (16$\pm$10 ppbv), S $O_4$$^{[-10]}$ (60$\pm$0 pptv), N $H_4$$^{＋}$(71$\pm$6 pptv), N $a^{＋}$(5$\pm$1 pptv), PAN(13$\pm$9 pptv), MeN $O_3$(3.5$\pm$1.5 pptv), 2-butyl N $O_3$(0.6$\pm$0.1 pptv), $H_2O$$_2$(1015$\pm$44 pptv), $C_2$C $l_4$(3.3$\pm$0.1 pptv), condensation nuclei(249$\pm$13c $m^{-3}$), and dew point(-8.5$\pm$5.3$^{\circ}C$) during this experiment..

• Journal of the Korean Association of Geographic Information Studies
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• v.11 no.4
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• pp.182-192
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• 2008

In oder to develop a decision supporting system for oil spill response, the prototype of pollution response support system which has integrated oil spill prediction system and pollution risk prediction system has developed for Incheon-Daesan area. Spill prediction system calculates oil spill aspects based on real-time wind data and real-time water flow and the residual volume of spilt oil and spread pattern are calculated considering the characteristic of spilt oil. In this study, real-time data is created from results of real-time meteorological forecasting model(National Institute of Environmental Research) using ftp, real-time tidal currents datasets are built using CHARRY(Current by Harmonic Response to the Reference Yardstick) model and real-time wind-driven currents are calculated applying the correlation function between wind and wind-driven currents. In order to model the feature which is spilt oil spreading according to real-time water flow is weathered, the decrease ratio by oil kinds was used. These real-time data and real-time prediction information have been integrated with ESI(Environmental Sensitivity Index) and response resources and then these are provided using GIS as a whole system to make the response strategy.

• Journal of Korea Water Resources Association
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• v.53 no.10
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• pp.903-915
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• 2020

Long-term high-resolution hydro-meteorological data has been recognized as an essential element in establishing the water resources plan. The increasing demand for spatial precipitation in various areas such as climate, hydrology, geography, ecology, and environment is apparent. However, potential limitations of the existing area-weighted and numerical interpolation methods for interpolating precipitation in high altitude areas remains less explored. The proposed PRISM (Precipitation-Elevation Regressions on Independent Slopes Model) model can produce gridded precipitation that can adequately consider topographic characteristics (e.g., slope and altitude), which are not substantially included in the existing interpolation techniques. In this study, the PRISM model was optimized with SCEM-UA (Shuffled Complex Evolution Metropolis-University of Arizona) to produce daily gridded precipitation. As a result, the minimum impact radius was calculated 9.10 km and the maximum 34.99 km. The altitude of coastal weighted was 681.03 m, the minimum and maximum distances from coastal were 9.85 km and 38.05 km. The distance weighting factor was calculated to be about 0.87, confirming that the PRISM result was very sensitive to distance. The results showed that the proposed PRISM model could reproduce the observed statistical properties reasonably well.

• Korean Journal of Remote Sensing
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• v.36 no.5_3
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• pp.1037-1051
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• 2020

The accurate monitoring and forecasting of the intensity of tropical cyclones (TCs) are able to effectively reduce the overall costs of disaster management. In this study, we proposed a multi-task learning (MTL) based deep learning model for real-time TC intensity estimation and forecasting with the lead time of 6-12 hours following the event, based on the fusion of geostationary satellite images and numerical forecast model output. A total of 142 TCs which developed in the Northwest Pacific from 2011 to 2016 were used in this study. The Communications system, the Ocean and Meteorological Satellite (COMS) Meteorological Imager (MI) data were used to extract the images of typhoons, and the Climate Forecast System version 2 (CFSv2) provided by the National Center of Environmental Prediction (NCEP) was employed to extract air and ocean forecasting data. This study suggested two schemes with different input variables to the MTL models. Scheme 1 used only satellite-based input data while scheme 2 used both satellite images and numerical forecast modeling. As a result of real-time TC intensity estimation, Both schemes exhibited similar performance. For TC intensity forecasting with the lead time of 6 and 12 hours, scheme 2 improved the performance by 13% and 16%, respectively, in terms of the root mean squared error (RMSE) when compared to scheme 1. Relative root mean squared errors(rRMSE) for most intensity levels were lessthan 30%. The lower mean absolute error (MAE) and RMSE were found for the lower intensity levels of TCs. In the test results of the typhoon HALONG in 2014, scheme 1 tended to overestimate the intensity by about 20 kts at the early development stage. Scheme 2 slightly reduced the error, resulting in an overestimation by about 5 kts. The MTL models reduced the computational cost about 300% when compared to the single-tasking model, which suggested the feasibility of the rapid production of TC intensity forecasts.

• The Korean Journal of Air & Space Law and Policy
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• v.35 no.1
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• pp.203-319
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• 2020

The regulation of satellite remote sensing is generally included with the scope of statutes governing outer space activities. But not all states opted for dedicated satellite remote sensing regulation. The decision whether to do so depends in part on the specific capabilities of national satellite remote sensing programs. Five states that have dedicated statutes governing operations with remote sensing data are the United States, with its developed Landsat regime (the Land Remote Sensing Policy Act of 1992, LRSPA), Canada, with its Remote Sensing Systems Act, Germany, with its Satellite Data Securities Protection Act (SatDSiG), France, with its Law on Space Operations (LOS), Japan, with its Act on Ensuring Appropriate Handling of Satellite Remote Sensing Data. The major purpose of this article is to shed light on some legal issues surrounding remote sensing activities by comparative review. The paper analyzes international conventions or soft law and national law and policies relating to satellite remote sensing. It also offers some implications and suggestions for regulations of satellite remote sensing operations and satellite data.