Urban heat island (UHI) is a phenomenon that occurs in cities worldwide. Therefore, there is an increasing need for studies on the changes in UHI intensity and long-term trends based on macroscopic characteristics related to urbanization. In this study, changes in seasonal UHI intensity based on urban area were analyzed for eight Asian mega cities from 1992-2012. The results indicate that the change in pattern of UHI intensity varies for different cities and seasons. UHI intensity increased as the urban area size increased. Furthermore, the dependency of UHI intensity on the economic situation was also demonstrated. With respect to the seasons, significantly increasing trends appeared during the summer. Moreover, depending on urban characteristics such as geography and climate, increasing trends appeared during other seasons. Population was also found to affect UHI intensity by generating anthropogenic heat; however, its effect as an individual factor appeared to be insignificant. This is a macroscale study that analyzes the effect of urban area size on UHI intensity. Future studies on urbanization factors and levels influencing the UHI intensity using higher resolution materials are required Sustainability 2020, 12, 112 2 of 11 characteristics or fundamental differences among them. The number of systematic empirical studies of the latter type has increased because of the accessibility of remote sensing with global coverage [9], and our study falls into this category. Several studies have indicated that continuing urbanization progressively increases the UHI intensity, and several others have demonstrated that the urban impact could have an effect on recent warming trends [10][11][12]. Hence, comparative studies on UHI changes for cities with different climatic and socio-economic situations, and on urban characteristics, are essential for researchers and decision-makers [6,[13][14][15][16].Several existing studies that focus on UHI at a macroscopic level were examined. Karl et al.[17] classified urbanization in cities of the United States based on population, and performed a time-series analysis for each season. The UHI intensity was defined as the temperature differences between urban and suburban areas with regard to the degree of urbanization. This was done by using the monthly temperature data from 1901-1984 obtained from 1219 observation stations of the historical climatology network. Although differences in urbanization and seasonality were confirmed in their study, there were limitations in the variability based on the location. Moreover, there was a difference in the degree of data construction between the eastern and western regions.Jones et al. [13] attempted to identify the effect of temperature increase due to urbanization by using the rural-station temperature data for three regions, namely the western Soviet Union, eastern Australia, and eastern China. However, there was a limitation in the study due to the varying numbers of observation stations and analysis periods; furthermore, significant trends...

Amorphous TbCo thin films were deposited in a plasma-exposed region using a facing target magnetron-sputtering system with a divergent magnetic field, which can provide a large plasma potential by the loss of electrons from the plasma. The deposition parameters were controlled by changing Ar pressure and deposition distance from the center line of the system. Columnar structures were commonly observed in amorphous TbCo films, except in the films deposited at low Ar pressure. The microstructures could not be closely related with the perpendicular magnetic anisotropy of the TbCo films. The films deposited in a high plasma-exposed region showed the unusual changes in deposition rates and magnetic-compensation composition with Ar pressure, which were quantitatively analyzed.

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Highly concentrated precipitation during the rainy season poses challenges to the South Korean water resources management in efficiently storing and redistributing water resources. Under the new climate regime, water resources management is likely to become more challenging with regards to water-related disaster risk and deterioration of water quality. To alleviate such issues by adjusting management plans, this study examined the impact of climate change on the streamflow in the Bocheongcheon basin of the Geumgang river. A globally accepted hydrologic model, the HEC-HMS model, was chosen for the simulation. By the calibration and the validation processes, the model performance was evaluated to range between “satisfactory” and “very good”. The calibrated model was then used to simulate the future streamflow over six decades from 2041 to 2100 under RCP4.5 and RCP8.5. The results indicated significant increase in the future streamflow of the study site in all months and seasons over the simulation period. Intensification of seasonal differences and fluctuations was projected under RCP 8.5, implying a challenge for water resources managers to secure stable sources of clean water and to prevent water-related disasters. The analysis of the simulation results was applied to suggest possible local adaptive water resources management policy.

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