• Journal of The Geomorphological Association of Korea
• /
• v.20 no.4
• /
• pp.85-99
• /
• 2013

The objective of this paper is to analyze the spatial distribution of errors in the DEM generated using waterlines from multi-temporal remote sensing data and to assess flood vulnerability. Unlike conventional research in which only global statistics of errors have been generated, this paper tries to quantitatively analyze the spatial distribution of errors from a probabilistic viewpoint using geostatistical simulation. The initial DEM in Baramarae tidal flats was generated by corrected tidal level values and waterlines extracted from multi-temporal Landsat data in 2010s. When compared with the ground measurement height data, overall the waterline-based DEM underestimated the actual heights and local variations of the errors were observed. By applying sequential Gaussian simulation based on spatial autocorrelation of DEM errors, multiple alternative error distributions were generated. After correcting errors in the initial DEM with simulated error distributions, probabilities for flood vulnerability were estimated under the sea level rise scenarios of IPCC SERS. The error analysis methodology based on geostatistical simulation could model both uncertainties of the error assessment and error propagation problems in a probabilistic framework. Therefore, it is expected that the error analysis methodology applied in this paper will be effectively used for the probabilistic assessment of errors included in various thematic maps as well as the error assessment of waterline-based DEMs in tidal flats.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.24 no.4
• /
• pp.438-444
• /
• 2018

Korea has recently selected twenty-two ports for reinforcement breakwater installation of protection facilities, due to rise sea level caused by global warming and increase in the number of typhoon and tsunami. In addition, due to consistent enlargement of ship size, dredging for depth of water for large vessel's berthing and enlargement of berth is under construction. However, no definite construction plan for the reinforcement and lengthening of crown height, which has close relationship with the safe mooring of ships. In this study, domestic and foreign design criteria of crown height were analyzed, and the crown height evaluation index and evaluation method were developed by dividing it into environment and ship elements. In particular, in the case of ship evaluation index, each step was set up in 4 steps according to domestic and foreign regulations, weighted by each step, and the safety level of crown height was evaluated. As a result of the mooring safety simulation of the 100,000 ton cruise ship, the appropriate minimum crown height standard was derived to be 3 m above A.H.H.W. The results of this study are expected to be used as basic data to propose the crown height standard reflecting ship characteristics.

• Korean Journal of Remote Sensing
• /
• v.34 no.3
• /
• pp.495-506
• /
• 2018

Global interest in climate change and sea level rise has led to active research on the velocities of glaciers. In studies about the velocity of glaciers, in-situ measurements can obtain the most accurate data but have limitations to acquire periodical or long-term data. Offset tracking using SAR is actively being used as an alternative of in-situ measurements. Offset tracking has a limitation in that the accuracy of observation is lower than that of other observational techniques, but it has been improved by recent studies. Recent studies in the $Uv{\hat{e}}rsbreen$ glacier area have shown that glacier altitudes decrease at a rate of 1.5 m/year. The glacier displacement velocities in this region are heavily influenced by climate change and can be important in monitoring and forecasting long-term climate change. However, there are few concrete examples of research in this area. In this study, we applied the improved offset tracking method to observe the two-dimensional velocity in the $Uv{\hat{e}}rsbreen$ glacier. As a result, it was confirmed that the glacier moved at a maximum rate of 133.7 m/year. The measruement precisions for azimuth and line-of-sight directions were 5.4 and 3.3 m/year respectively. These results will be utilized to study long-term changes in elevation of glaciers and to study environmental impacts due to climate change.

• Spatial Information Research
• /
• v.17 no.3
• /
• pp.341-350
• /
• 2009

As the power and scale of typhoons are growing due to global warming and socioeconomic damages induced by super-typhoons are increasing, it is important to estimate inundation damages and to prepare proper adaptation plans against an attack of the super-typhoon. In this paper, we estimated the inundation damages of urban area around Haeundae beach induced by super-typhoons which follow the route of Typhoon Maemi with the conditions of Typhoon Vera (Ise Bay in Japan, 1959), Typhoon Durian (Philippine, 2006) and Hurricane Katrina (New Oleans in U.S.A, 2005). The coastal area around the Haeundae beach (Busan and Gyeongnam province) is expectedly damaged by severe storm surges. In this study we calculated the rise of sea level height after harmonizing the different datum levels of land and ocean and estimated the inundation depth, inundation area and the amount of building damages by using airborne LiDAR data and GIS spatial analysis techniques more accurately and quantitatively. As many researchers are predicting that super-typhoon of overwhelming power will occur around the Korean peninsula in the near future, the results of this study are expected to contribute to producing coastal inundation map and evacuation planning.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.27 no.5
• /
• pp.691-699
• /
• 2021

The global surface temperature has risen critically over the past century and according to the IPCC Fifth Assessment Report 2014, existing risks in natural and human systems will worsen. Coastal erosion is mostly caused by climate change and among all the coastal areas at risk, Benin, which is part of the Gulf of Guinea, has been ranked very highly as a vulnerable region. Therefore, in this review, we focus on the evolution of coastline change in Cotonou of Benin, summarizing its resultant impacts and applied measures around the coast area by reviewing previous studies. Signs of coastal erosion in Cotonou appeared in 1963. After 39 years, the east shoreline of Cotonou has retreated by 885 m, resulting in the disappearance of more than 800 houses. To solve this problem, Benin authorities built seven groynes in 2013, and have increased the number of the structure as a way to interrupt water flow and limit the movement of sediment. Over the region, shorelines appeared preserved accordingly. In contrast, areas located further east, where groynes were not installed, have suf ered from intensive erosion at a rate of 49 m/yr. In the future, as a next step, the effectiveness of groynes should be studied with local and broader perspectives.

• Journal of Environmental Impact Assessment
• /
• v.28 no.1
• /
• pp.23-34
• /
• 2019

Global warming becomes a serious issue that poses subsidiary issues like a sea level rise or a capricious climate over the world. Because of severe heat-wave of the summer in Korea in 2016, a big attention has been focused on urban heat island since then. Not just about heat-wave itself, many researches have been concentrated on how to adapt in this trendy warming climate and weather in a small scope. A big part of existing studies is mitigating "Urban Heat Island effect" and that is because of huge impervious surface in urban area where highly populated areas do diverse activities. It is a serious problem that this thermal context has a high possibility causing mortality by heat vulnerability. However, there have been many articles of a green infrastructures' cooling impact in summer. This research pays attention to measure cooling effect of a street planting considering urban canyon and type of green infrastructures in neighborhood scale. This quantitative approach was proceeded by ENVI-met simulation with a spatial scope of a commercial block in Seoul, Korea. We found the dense double-row planting is more sensitive to change in temperature than that of the single-row. Among the double-row planting scenarios, shrubs which have narrow space between the plant and the land surface were found to store heat inside during the daytime and prevent emitting heat so as to have a higher temperature at night. The quantifying an amount of vegetated spaces' cooling effect research is expected to contribute to a study of the cost and benefit for the planting scenarios' assessment in the future.

• Journal of Appropriate Technology
• /
• v.7 no.2
• /
• pp.136-143
• /
• 2021

Pacific island countries, including Kiribati, are suffering from a shortage of essential resources as well as a reduction in their living space due to sea level rise and coastal erosion from climate change, groundwater pollution and vegetation changes. Global activities to solve these problems are being progressed by the UN's efforts to implement SDGs. Pacific island countries can adapt to climate change by using abundant marine resources. In other words, seawater plants can assist in achieving SDGs #2, #6 and #7 based on SDGs #14 in these Pacific island countries. Under the auspice of Korea International Cooperation Agency (KOICA), Korea Research Institute of Ships and Ocean Engineering (KRISO) established the Sustainable Seawater Utilization Academy (SSUA) in 2016, and its 30 graduates formed the SSUA Kiribati Association in 2017. The Ministry of Oceans and Fisheries (MOF) of the Republic of Korea awarded ODA fund to the Association. By taking advantage of seawater resource and related plants, it was able to provide drinking water and vegetables to the local community from 2018 to 2020. Among the various fields of education and practice provided by SSUA, the Association hope to realize hydroponic cultivation and seawater desalination as a self-support project through a pilot project. To this end, more than 140 households are benefiting from 3-stage hydroponics, and a seawater desalination system in connection with solar power generation was installed for operation. The Association grows and supplies vegetable seedlings from the provided seedling cultivation equipment, and is preparing to convert to self-support business from next year. The satisfaction survey shows that Tarawa residents have a high degree of satisfaction with the technical support and its benefits. In the future, it is hoped that SSUA and regional associations will be distributed to neighboring island countries to support their SDGs implementations.