New Definition Method for Urban and Rural Regions Considering Surrounding Environments of Observation Stations Over South Korea

This study proposes a new approach to defining and analyzing the urbanization effects of temperature over South Korea. While the conventional method of distinguishing between urban and rural stations relies on population criteria, this study has developed an approach to differentiate between urban and rural stations by considering the proportion of natural environments and artificial objects surrounding each station. The long-term temperature changes exhibit a statistically more significant relationship with the proportion of artificial objects compared to the population size, and the new method provides a clearer distinction between urban and rural stations. In addition, based on the categorized stations, an urbanization contribution index (UCI) is calculated to quantitatively compare temperature changes between urban and rural stations. As a result, it is confirmed that the method based on the ratio of artificial features better captures the urbanization effect of temperature compared to the population-based method. In particular, the urbanization effect is found to be more pronounced during nighttime, with the largest difference between urban and rural stations observed in the daily minimum temperature. The new method effectively captures the thermal attributes of urban and rural stations, with a stronger emphasis on nocturnal differentiations. This study emphasizes the importance of considering the surrounding environments rather than population alone to accurately understand the urbanization effects.