• Journal of the Korean earth science society
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• v.23 no.5
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• pp.436-441
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• 2002

This study is concerned with the sea breeze criterion and climatological characteristics of the short-time sea breeze in the Gangneung coastal area. The sea breeze criteria in this area are listed here. First, the fact of the sea breeze blowing was considered to be a change of wind direction from land to sea and vice versa without terrain effect like easterly wind. Second, the sea breeze of which continuous time 1-hour or 2-hour was selected. Then the climatological characteristics of the short-time sea breeze were analyzed using the meterological data from a 10-year(1988${\sim}$1997) period. The climatological characteristics which were analyzed for the short-time sea breeze consist of the frequency, onset time, wind direction speed and temperature. Finally, this study will be helpful in meteorological application through the climatological characteristics of sea breeze along the east coast as well as Gangneung Airport.

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.2
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• pp.188-196
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• 2023

Among marine accidents caused by bad weather, visibility restrictions caused by sea fog occurrence cause accidents such as ship strand and ship bottom damage, and at the same time involve casualties caused by accidents, which continue to occur every year. In addition, low visibility at sea is emerging as a social problem such as causing considerable inconvenience to islanders in using transportation as passenger ships are collectively delayed and controlled even if there are local differences between regions. Moreover, such measures are becoming more problematic as they cannot objectively quantify them due to regional deviations or different criteria for judging observations from person to person. Currently, the VTS of each port controls the operation of the ship if the visibility distance is less than 1km, and in this case, there is a limit to the evaluation of objective data collection to the extent that the visibility of sea fog depends on the visibility meter or visual observation. The government is building a marine weather signal sign and sea fog observation networks for sea fog detection and prediction as part of solving these obstacles to marine traffic safety, but the system for observing locally occurring sea fog is in a very insufficient practical situation. Accordingly, this paper examines domestic and foreign policy trends to solve social problems caused by low visibility at sea and provides basic data on the need for government support to ensure maritime traffic safety due to sea fog by factually investigating and analyzing social problems. Also, this aims to establish a more stable maritime traffic operation system by blocking marine safety risks that may ultimately arise from sea fog in advance.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2002.10a
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• pp.81-84
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• 2002

The Sea dike tidal closure works has traditionally ended in the failure. Therefore, the success of the tidal closure in Hwaong in the sea near Inchon where has the greatest tidal gap in our country deserves to consider its meaning. While its process was going on, we had the difficulty like bad weather, unexpected ground settlement, flow velocity beyond the imagine, etc. Moreover, environment group's rush was so fierce that the works could have been delayed. This works showed that not only technical aspects but also social problems(environment group's rush and public discontents) were important factors in accomplishing the works. Finally, all of the difficulties were overcome and the tidal closure works were successful. So, This success is the best example in a kind of the another works in itself.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.25 no.1
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• pp.1-10
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• 2017

A heavy foggy event accompanying with complex coastal fog was investigated in this study. This heavy foggy event occurred on FEB 11, 2015. Due to reduced visibility with this foggy event induced more than 100times serial traffic accidents over the Young-jong highway, and Flights from 04:30 AM to 10:00 AM were cancelled on Inchon International Airport. This heavy foggy event was occurred in synoptic and mesoscale environments but dense coastal fog were combined with a combination of sea fog, steam fog, and radiation fog. This kind of coastal fog can predicted by accurate analysis of the direction of the air flow, sea surface temperature(SST), and 925hPa isotherms from numerical weather prediction charts and real time analysis charts.

• Journal of Ocean Engineering and Technology
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• v.7 no.1
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• pp.56-61
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• 1993

Standard values in graphic porms are presented for the ratio of added wave resistance to the sun of added wave and wind resistances in head sea for three ship types, tanker, container ship and passenger ship. The effect of ship length on the ratio defined above is investigated for the three ship types. Obique sea added resistance is determined using wave direction reduction factor. The factor is obtained from model test results and cubic spline interpolation technique.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.1203-1205
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• 2003

To detect dust-loaded air-mass over land and ocean, we propose an index, which is essentially the difference in Rayleigh-corrected reflectance between 412 and 443 nm bands of SeaWiFS. Radiative transfer simulations are conducted to show that the index is linearly related to the optical thickness of modeled dust-contaminated aerosol while showing insensitivity against non-absorbing model aerosols. Asian SeaWiFS data set of 2001 spring is used to produce daily composite imagery of the index, which compares well with TOMS Aerosol Index and with predicted aerosol optical thickness predicted by CFORS chemical weather forecast.

• Journal of The Geomorphological Association of Korea
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• v.19 no.3
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• pp.71-82
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• 2012

This research was carried out to estimate annual erosion and retreat rates by using datum-point and to identify the characteristics and causes of seasonal variations of sea-cliff slope in Pado-ri, Taean-gun. In the result, the erosion and retreat rates of sea-cliff were increased from spring to summer. The rates were increased rapidly between August and October, caused by the effects of extreme weather events such as severe rainstorms and typhoons, etc. Since then, the erosion and retreat rates of sea-cliff were decreased gradually, but the rates were increased again in winter due to the storm surge and mechanical weathering resulting from the repeated freezing and thawing actions of bed rocks. The factors that affect erosion and retreat rates of sea-cliff include the number of days with antecedent participation and daily maximum wave height. In particular, it turned out that the erosion is accelerated by strong wave energy during storm surges and typhoons. The annual erosion and retreat rates of study area for the past two years(from May 2010 to May 2012) were approximately 44~60cm/yr in condition of differences in geomorphological and geological characteristics at each point. These erosion and retreat rates were found to be higher than results of previous researches. This is caused by coastal erosion forces strengthened by extreme weather events. The erosion and retreat process of sea-cliff in the study area is composed by denudation of onshore areas in addition to marine erosion(wave energy).

• Journal of Korean Society for Atmospheric Environment
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• v.18 no.2
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• pp.67-83
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• 2002

The coupled model (SMART) of dynamic meteorology model and particle dispersion model was developed. The numerical experiment on the relationship between change of land use and diffusion behavior in complex terrain was carried out using this model. It tried to investigate the change of particle diffusion behavior and local weather under the condition in which land-land breeze and sea breeze and mountain breeze intermingled. The numerical experiment results are as follows; 1) The more complicated local circulation field of the interaction of sea breeze, mountain breeze and Land -land breeze is formed. Then, the region circulation in which the urbanization is specific by location of the region is strengthened and is weakened. 2) Though in the region with dominant sea breeze, Land-land breeze does not appear directly, the progress of the sea wind to the inland is affected. 3) In the prediction of the air diffusion, emission high quality and accurate information of the emission site are important. That is to say, the dispersion predicting result which emission high quality and small error of the site perfectly vary for Land - land breeze in the effect may be brought about.

• Proceedings of the KSRS Conference
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• v.1
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• pp.146-149
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• 2006

Marine surface winds observed by two microwave sensors, SeaWinds and Advanced Microwave Scanning Radiometer (AMSR), on the Advanced Earth Observing Satellite-II (ADEOS-II) are evaluated by comparison with off-shore moored buoy observations. The wind speed and direction observed by SeaWinds are in good agreement with buoy data with root-mean-squared (rms) differences of approximately 1 m $s^{-1}$ and $20^{\circ}$, respectively. No systematic biases depending on wind speed or cross-track wind vector cell location are discernible. The effects of oceanographic and atmospheric environments on the scatterometry are negligible. The wind speed observed by AMSR also exhibited reasonable agreement with the buoy data in general with rms difference of 1.2 m $s^{-1}$. Systematic bias which was observed in earlier versions of the AMSR winds has been removed by algorithm refinements. Intercomparison of wind speeds globally observed by SeaWinds and AMSR on the same orbits also shows good agreements. Global wind speed histograms of the SeaWinds data and European Centre for Medium-range Weather Forecasts (ECMWF) analyses agree precisely with each other, while that of the AMSR wind shows slight deviation from them.

• Ocean and Polar Research
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• v.23 no.2
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• pp.181-188
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• 2001

We describe here the Korea ocean prediction system that closely resembles operational numerical weather prediction systems. This prediction system will be served for real-time forecasts. The core of the system is a three-dimensional primitive equation numerical circulation model, based on ${\sigma}$-coordinate. Remotely sensed multi-channel sea surface temperature (MCSST) is imposed at the surface. Residual subsurface temperature is assimilated through the relationship between vertical temperature structure function and residual of sea surface height (RSSH) using an optimal interpolation scheme. A unified grid system, named as [K-E-Y], that covers the entire seas around Korea is used. We present and compare hindcasting results during 1990-1999 from a model forced by MCSST without incorporating RSSH data assimilation and the one with both MCSST and RSSH assimilated. The data assimilation is applied only in the East Sea, hence the comparison focuses principally on the mesoscale features prevalent in the East Sea. It is shown that the model with the data assimilation exhibits considerable skill in simulating both the permanent and transient mesoscale features in the East Sea.