A surface urban heat island (SUHI) is a significant meteorological phenomenon of the microclimate and environment in urban territories. Knowledge about the variations of SUHI is critical for urban planning and public welfare. In the current study, the seasonal and spatial changes of the Istanbul SUHI and its interactions with spectral indicators of the urban heat phenomenon including the normalized difference vegetation index (NDVI), tasseled cap wetness (TCW), and surface albedo were analyzed. The National Aeronautics and Space Administration (NASA) L2 thermal products (brightness temperature) of Landsat 8 imageries were used to calculate land surface temperature (LST) values. The thermal islands of the study area were detected based on the Urban Thermal Field Variation Index method. The retrieved LST values showed acceptable agreement with in situ observations of mean daily temperature for all the seasons. Monthly precipitation, however, demonstrated good correlation with summer and autumn LSTs. It is found that the central parts of the metropolitan area were subject to the most intense SUHI in the spring and summer seasons. Outskirt areas showed higher thermal values during cooler seasons of autumn and winter. The results of spatio-temporal interactions of SUHI and the spectral indicators revealed a negative correlation for NDVI and TCW and a positive correlation for surface albedo during different seasons from summer 2017 to spring 2018. The highest and lowest correlations were found between SUHI and TCW (spring) and surface albedo (winter), respectively. The regression results overall suggested that TCW and NDVI were the best indicators of SUHI in Istanbul. Surface albedo was not recommended for seasonal monitoring practices of SUHI in the study area due to the high differences in its seasonal interactions.

中文翻译：

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地表城市热岛的时空相互作用及其光谱指标：以土耳其伊斯坦布尔大都市地区为例。

地表城市热岛（SUHI）是城市地区微气候和环境的重要气象现象。有关SUHI变化的知识对于城市规划和公共福利至关重要。在本研究中，分析了伊斯坦布尔SUHI的季节和空间变化及其与城市热现象光谱指标的相互作用，包括归一化植被指数（NDVI）、,穗湿度（TCW）和地表反照率。美国国家航空航天局（NASA）的Landsat 8影像的L2热产品（亮度温度）用于计算陆地表面温度（LST）值。根据城市热场变化指数法检测研究区域的热岛。检索到的LST值与所有季节的平均日温度的原位观测值均显示可接受的一致性。然而，月降水量与夏季和秋季的LSTs表现出良好的相关性。发现在春季和夏季，大都市区的中部地区受到最强烈的SUHI威胁。郊区地区在秋季和冬季的凉爽季节表现出较高的热值。SUHI和光谱指标的时空相互作用结果显示，从2017年夏季到2018年春季的不同季节，NDVI和TCW呈负相关，而表面反照率呈正相关.SUHI和TCW之间的相关性最高和最低（春季）和表面反照率（冬季）。总体回归结果表明，TCW和NDVI是伊斯坦布尔SUHI的最佳指标。不建议在研究区域对SUHI进行季节性监测，因为其季节性相互作用差异很大。