都市街谷微氣候模型之建置與應用-以台北市溫羅汀街區為例

Abstract

過去微氣候模擬的相關研究皆著重於個案分析，但在個案研究之結果較難以衍伸類推至大範圍應用，故本研究希望以國家尺度下，提出一些有效的微氣候改善成果，作為擬定國家未來減碳政策之參考。 本研究微氣候模型建置以影響都市街谷微氣候之因子為首要研究目標，因此本研究針對街道高寬比、路寬、建築反射率以及街道坐向等四個因子建立一個27種不同的街谷型態模型。從研究成果發現建築反射率及街道坐向對於都市街谷溫度貢獻度低可忽略，而影響都市街谷溫度較明顯之因子為高寬比、路寬以及高寬比與街路寬之交互作用，其平均貢獻度依序分別為24.90%、23.20%、41.61%。 而根據變異數分析，得出高寬比與街路寬之交互作用對於影響都市街谷溫度具有顯著性，本研究結果在任何情境下，高寬比為1時都市街谷平均溫度較高，尤其以高寬比為1、路寬為26 m時為最高；隨著路寬越小，高寬比越大時，也會有較高的平均溫度。本研究根據結果得出種植行道樹之降溫效益，夏季白天為0.058℃，夏季夜間為0.017℃，冬季白天與夜間為0.007℃，最後本研究根據上述研究成果，應用在溫羅汀街區之研究，成功模擬微氣候大範圍尺度並以個案分析當作應用。

Traditionally, microclimate modeling has been based on case studies, but the results of the case studies cannot be applied to large-scale applications. As a result, this study aims to provide some useful results of microclimate improvement using national GHG reduction targets as a reference for future policies to reduce carbon emissions. This study focuses on four factors, such as street height-and-width ratio, road width, building reflectance and street orientation, to establish 27 different models of street valley patterns. Based on the results of the research, it was found that building reflectance and street orientation contributed negligible to the urban valley temperature, while the most significant factors influencing the urban valley temperature were the height-to-width ratio, street width and the interaction between height-to-width ratio and street width, contributing 24.90%, 21.27%, and 41.61%, respectively. According to the analysis of variance, an interaction between height-to-width ratio and street width influenced the urban valley temperature significantly. When the height-to-width ratio was 1 in all cases, the average urban valley temperature was higher, especially when the height-to-width ratio was 1 and the street width was 26 m. The average temperature was also higher when the height-to-width ratio was larger and the street width was smaller. This study found that planting street trees cooled the air by 0.058°C during the daytime during summer, 0.017°C during the nighttime during summer, and 0.007°C during the daytime and nighttime during winter. Lastly, the microclimate was successfully simulated on a large scale and applied as a case study to the Winrodin district.