臺北都會區北部地區地表覆蓋變遷下之氣溫變化分析

Abstract

過去三十年來，臺北都會區北部的都市發展導致了大量綠地與農地轉為建成區的地表覆蓋變化。為探討此類變化如何影響夏季白天與夜間的近地表空氣溫度，本研究分析1990年至2023年間的氣溫變化趨勢。研究方法結合衛星影像進行的土地覆蓋分類、臺灣氣象觀測站資料，以及臺灣歷史氣候重建資料（TReAD），並依據不同土地覆蓋類型進行分類分析。 研究結果顯示，新興都市化區域，特別是林口與龜山，出現最顯著的升溫，夜間氣溫上升超過2 °C。相較之下，綠地比例較高或海拔較高的區域則呈現較小的氣溫增幅，凸顯綠地與地形在緩和氣溫上升方面的作用。1990年代至2000年代初期的資料顯示，夜間升溫相對較強，而2010年代以後則顯示白天升溫趨勢明顯上升，在都市核心區中更與夜間升溫持平甚至超越，可能與不透水鋪面增加、綠地減少以及通風不良導致的日間熱累積效應有關。 整體而言，研究結果顯示地表覆蓋組成與在地環境條件共同影響都市熱環境的時空變化。雖然TReAD為基於觀測資料建構的模擬資料，其格網化的特性有助於掌握區域性氣候趨勢，但氣象觀測站則能補足模型對微氣候變異的限制。整合兩種資料來源有助於更全面理解都市氣溫變化機制，為未來都市發展、綠地配置與熱風險緩解策略提供實證參考。

Urban development in the northern Taipei Metropolitan Area has resulted in extensive conversion of vegetated and agricultural land to built-up surfaces over the past three decades. This study investigates how such land cover changes have influenced summer daytime and nighttime air temperatures from 1990 to 2023. Using satellite-derived land cover classifications, Taiwan’s weather station observations, and the Taiwan Re-Analysis Downscaling dataset (TReAD), temperature trends were assessed across clustered land cover types. The findings show that newly urbanized areas—especially Linkou and Guishan—experienced the highest warming, with nighttime temperatures rising by over 2 °C. In contrast, vegetated and higher elevation areas showed less warming, suggesting that green space and topography help moderate temperature increases. While the 1990s to early 2000s were marked by stronger nighttime warming, recent years (2010s onward) show a shift toward intensified daytime warming, particularly in long-urbanized city centers where built-up surfaces and reduced airflow may amplify heat buildup. These findings suggest that both land cover and local environmental conditions shape temperature changes over time. This study shows the value of combining gridded model outputs with station data to better understand urban heat warming trends. Insights from the findings may help inform decision makers regarding development consequences and potential land use interventions.