• Ocean Systems Engineering
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• v.7 no.4
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• pp.319-328
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• 2017

Higher prediction efficacy is a very challenging task in any field of engineering. Due to global warming, there is a considerable increase in the global sea level. Through this work, an attempt has been made to find the sea level variability due to climate change impact at Haldia Port, India. Different statistical downscaling techniques are available and through this paper authors are intending to compare and illustrate the performances of three regression models. The models: Wavelet Neural Network (WNN), Minimax Probability Machine Regression (MPMR), Feed-Forward Neural Network (FFNN) are used for projecting the sea level variability due to climate change at Haldia Port, India. Model performance indices like PI, RMSE, NSE, MAPE, RSR etc were evaluated to get a clear picture on the model accuracy. All the indices are pointing towards the outperformance of WNN in projecting the sea level variability. The findings suggest a strong recommendation for ensembled models especially wavelet decomposed neural network to improve projecting efficiency in any time series modeling.

• Journal of Environmental Impact Assessment
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• v.21 no.5
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• pp.757-765
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• 2012

The purpose of this study was to estimate the spatial-temporal NPP(Net Primary Productivity) and SCS(Soil Carbon Storage) of forest ecosystem under climate change in the capital area of South Korea using Mapss-Century1 (MC1), one of Dynamic Global Vegetation Models (DGVMs). The characteristics of the NPP and SCS changes were simulated based on a biogeochemical module in this model. As results of the simulation, the NPP varies from 2.02 to 7.43 tC $ha^{-1}\;yr^{-1}$ and the SCS varies from 34.55 to 84.81 tC $ha^{-1}$ during 1971~2000 respectively. Spatial mean NPP showed a little decreasing tendency in near future (2021~2050) and then increased in far future (2071~2100) under the condition of increasing air temperature and precipitation which were simulated by the A1B climate change scenario of Intergovernmental Panel on Climate Change (IPCC). But it was estimated that the temporal change of spatial mean NPP indicates 4.62% increasing tendency in which elevation is over 150m in this area. However, spatial mean SCS was decreased in the two future periods under same climate condition.

• Journal of Astronomy and Space Sciences
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• v.25 no.4
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• pp.395-404
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• 2008

We explore the linkage between the long term variability of the Sun and earth's climate change by analysing periodicities of time series of solar proxies and global temperature anomalies. We apply the power spectral estimation method named as the periodgram to solar proxies and global temperature anomalies. We also decompose global temperature anomalies and reconstructed total solar irradiance into each local variability components by applying the EMD (Empirical Mode Decomposition) and MODWT MRA (Maximal Overlap Discrete Wavelet Multi Resolution Analysis). Powers for solar proxies at low frequencies are lower than those of high frequencies. On the other hand, powers for temperature anomalies show the other way. We fail to decompose components which having lager than 40 year variabilities from EMD, but both residuals are well decomposed respectively. We determine solar induced components from the time series of temperature anomalies and obtain 39% solar contribution on the recent global warming. We discuss the climate system can be approximated with the second order differential equation since the climate sensitivity can only determine the output amplitude of the signal.

• Journal of Energy Engineering
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• v.27 no.3
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• pp.36-40
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• 2018

Climate change is one of the major issues in both the developed and developing world. Greenhouse gas (GHG) emission is one of the implications for climate change. It is increasing rapidly. Although the emission is much less when compared to the rest of the world, Ethiopia has also faced this global issue. The major source for GHG emission in Ethiopia is agriculture. Therefore, the agriculture sector has to be given more attention in Ethiopia. To overcome the problem, Climate-Resilient Green Economy (CRGE) strategy has been initiated. One way of executing this target is to create a sustainable and environmentally friendly pathway to use agricultural byproducts. Sugarcane is one of the major plants in Ethiopia. Its byproducts are bagasse, molasses, and press mud. Since it is a waste product, it is economical and creates a sustainable and green environment by reducing GHG emissions. Sugarcane byproducts have versatile applications like as fuel, as cement replacing material, as a mitigation for expansive soils, as biosorbent for the treatment of water and wastewater and also as a wood material. However, Ethiopia has not used this byproduct massively as it is readily available. This paper reviews the possible applications of sugarcane byproducts to mitigate climate change.

• Journal of The Korean Society of Agricultural Engineers
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• v.51 no.3
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• pp.25-35
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• 2009

Climate change due to global warming possibly effects the agricultural water use in terms of evapotranspiration. Thus, to estimate rice evapotranspiration under the climate change, future climate data including precipitation, minimum and maximum temperatures for 90 years ($2011{\sim}2100$), were forecasted using LARS-WG. Observed 30 years ($1971{\sim}2000$) climate data and climate change scenario based on SRES A2 were prepared to operate the LARS-WG model. Using these data and FAO Blaney-Criddle method, reference evapotranspiration and rice evapotranspiration were estimated for 9 different regions in South Korea and rice evapotranspiration of 10 year return period was estimated using frequency analysis. As the results of this study, rice evapotranspiration of 10 year return period increased 1.56%, 5.99% and 10.68% for each 30 years during $2011{\sim}2100$ (2025s; $2011{\sim}2040$, 2055s; $2041{\sim}2070$, 2085s; $2071{\sim}2100$) demonstrating that the increased temperature from the climate change increases the consumptive use of crops and agricultural water use.

• Journal of Soil and Groundwater Environment
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• v.21 no.6
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• pp.22-35
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• 2016

Global climate change could have an impact on hydrological process of a watershed and result in problems with future water supply by influencing the recharge process into the aquifer. This study aims to assess the change of groundwater recharge rate by climate change and to predict the sustainability of groundwater resource in Pyoseon watershed, Jeju Island. For the prediction, the groundwater recharge rate of the study area was estimated based on two future climate scenarios (RCP 4.5, RCP 8.5) by using the Soil Water Balance (SWB) computer code. The calculated groundwater recharge rate was used for groundwater flow simulation and the change of groundwater level according to the climate change was predicted using a numerical simulation program (FEFLOW 6.1). The average recharge rate from 2020 to 2100 was predicted to decrease by 10~12% compared to the current situation (1990~2015) while the evapotranspiration and the direct runoff rate would increase at both climate scenarios. The decrease in groundwater recharge rate due to the climate change results in the decline of groundwater level. In some monitoring wells, the predicted mean groundwater level at the year of the lowest water level was estimated to be lower by 60~70 m than the current situation. The model also predicted that temporal fluctuation of groundwater recharge, runoff and evapotranspiration would become more severe as a result of climate change, making the sustainable management of water resource more challenging in the future. Our study results demonstrate that the future availability of water resources highly depends on climate change. Thus, intensive studies on climate changes and water resources should be performed based on the sufficient data, advanced climate change scenarios, and improved modeling methodology.

• Hwankyungkyoyuk
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• v.23 no.3
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• pp.50-61
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• 2010

As the influence of mankind's actions grows on the earth's climate, the necessity of climate change education is increasing everyday. Therefore, this study will discuss desirable courses about climate changes education that can be used throughout the world. It is meaningful to try to compare the contents and scope of earth global warming education courses of different nations. where education and a research about earth global warming occur simlutaneously. This is key because global warming is not just a national issue, but an international issue. Therefore this study need to understand the status of environmental education is over the world to devise an improvement plan help to solve the problem of climate change on an international level. Therefore, this study compared, the global warming educational contents which appeared in Korean textbooks to Japanese and American textbooks, and analyzed commonalities and differences of each. Also, we will discuss desirable global warming educational instructional strategies. This study analyzed the present situation of nations by looking at common points and differences using an analysis form. Even though the researchers of an each nation analyzed the teaching material through common analysis forms, this study utilized a common analysis method with a colleague researcher regarding environmental education, environment, environmental science to increase the validity of the study in each nation. Also the difference and similarities were aggregated as This study collected the analysis results of each nation. The researchers utilized the results of the analyses to engage in repeated discussion and the sharing of results.

• Atmosphere
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• v.20 no.1
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• pp.49-61
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• 2010

Atmospheric aerosols play a crucial role for changing climate, resulting in a wide range of uncertainty for future climate prediction. In this paper we review current international research status and trend of climate-related aerosol science. There have been carried out a number of campaigns (including ACE-Asia, TRACE-P, ABC, and so on) and special experiments with some modeling studies over Korea, East Asia, and the Northwestern Pacific to characterize the various properties (physical, chemical, optical, and radiative) of Asian aerosols and evaluate their climate forcing impacts. But some parts of the aerosol research may need to be improved, advanced, or newly launched. Especially, a chemical transport model (CTM) embedded by a general circulation model (GCM) should be developed by the national scientific community with a high research priority, actively collaborating with international community in order to estimate direct and indirect global radiative forcing due to anthropogenic and natural aerosols.

• Journal of the Korean Association of Geographic Information Studies
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• v.14 no.3
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• pp.136-149
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• 2011

The aim of this study is to develop future climate scenario by downscaling the regional climate model (RCM) from global climate model (GCM) based on IPCC A1B scenario. To this end, the study first resampled the KMA-RCM(Korea meteorological administration-regional climate model) from spatial resolution of 27km to 1km. Second, observed climatic data of temperature and rainfall through 1971-2000 were processed to reflect the temperature lapse rate with respect to the altitude of each meteorological observation station. To optimize the downscaled results, Co-kriging was used to calculate temperature lapse-rate; and IDW was used to calculate rainfall lapse rate. Fourth, to verify results of the study we performed correlation analysis between future climate change projection data and observation data through the years 2001-2010. In this study the past climate data (1971-2000), future climate change scenarios(A1B), KMA-RCM(Korea meteorological administration-regional climate model) results and the 1km DEM were used. The research area is entire South Korea and the study period is from 1971 to 2100. Monthly mean temperatures and rainfall with spatial resolution of 1km * 1km were produced as a result of research. Annual average temperature and precipitation had increased by $1.39^{\circ}C$ and 271.23mm during 1971 to 2100. The development of downscaling method using GIS and verification with observed data could reduce the uncertainty of future climate change projection.

• Journal of The Korean Society of Agricultural Engineers
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• v.57 no.5
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• pp.69-80
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• 2015

The majority of projections of future climate come from Global Circulation Models (GCMs), which vary in the way they were modeled the climate system, and so it produces different projections about conceptualizing of the weather system. To implement climate change impact assessment, it is necessary to analyze trends of various GCMs and select appropriate GCM. In this study, climate data in 25 GCMs 41 outputs provided by Coupled Model Intercomparison Project Phase 5 (CMIP5) was downscaled at eight stations. From preliminary analysis of variations in projected temperature, precipitation and evapotranspiration, five GCM outputs were identified as candidates for the climate change impact analysis as they cover wide ranges of the variations. Also, GCM outputs are compared with trends of HadGCM3-RA, which are established by the Korean Meteorological Administration. From the results, it can contribute to select appropriate GCMs and to obtain reasonable results for the assessment of climate change.