Moisa Mitiku Badasa, Gemeda Dessalegn Obsi
Department of Agricultural Engineering, Faculty of Technology, Wollega University, Shambu Campus, Ethiopia.
Department of Natural Resource Management, College of Agriculture and Veterinary Medicine, Jimma University, Ethiopia.
Heliyon. 2022 Aug 10;8(8):e10185. doi: 10.1016/j.heliyon.2022.e10185. eCollection 2022 Aug.
Land use land cover (LULC) conversion around urban areas is the root cause for the increasing trend of land surface temperature (LST) in many cities. The increase in LST is driven by the replacement of vegetation cover and other LULC by impervious surface. This study is aimed to assess the extent of urban thermal field variance index (UTFVI) and thermal comfort level of Addis Ababa city using geospatial techniques and linear regression model. Landsat image of 1990 TM, 2000 of ETM+ and 2020 of OLI/TIRS are used to analyze LST and Urban Heat Islands (UHI) for assessing UTFVI and urban thermal comfort level. The results showed that the UHI over Addis Ababa city is substantial increased over the past decades. The results reveled that LST has increased by 7.9 °C due to decline of vegetation cover and expansion of built-up area. Results show that about 225 km (42.7%) is excellent comfort for urban resident while about 241.4 km (45.8%) is categorized as worst ecological evaluation index, which results discomfort to the city dwellers. The key findings of from this study are crucial for informing city administrators and urban planners to reduce urban heat islands by investing on urban green areas and open spaces.
城市周边土地利用土地覆盖（LULC）的转变是许多城市地表温度（LST）呈上升趋势的根本原因。LST的上升是由不透水表面取代植被覆盖和其他LULC所致。本研究旨在运用地理空间技术和线性回归模型，评估亚的斯亚贝巴市的城市热场变异指数（UTFVI）范围和热舒适水平。利用1990年的TM、2000年的ETM+以及2020年的OLI/TIRS Landsat影像分析LST和城市热岛（UHI），以评估UTFVI和城市热舒适水平。结果表明，在过去几十年里，亚的斯亚贝巴市的城市热岛效应显著增强。结果显示，由于植被覆盖减少和建成区扩张，LST上升了7.9℃。结果表明，约225平方公里（42.7%）对城市居民来说热舒适度极佳，而约241.4平方公里（45.8%）的生态评价指数最差，会给城市居民带来不适。本研究的主要发现对于告知城市管理者和城市规划者通过投资城市绿地和开放空间来减少城市热岛效应至关重要。
