Indian Institute of Science, Bengaluru, India.
Indian Institute of Remote Sensing, ISRO, Dehradun, India.
J Environ Manage. 2015 Jan 15;148:143-52. doi: 10.1016/j.jenvman.2013.11.034. Epub 2013 Dec 17.
Surface energy processes has an essential role in urban weather, climate and hydrosphere cycles, as well in urban heat redistribution. The research was undertaken to analyze the potential of Landsat and MODIS data in retrieving biophysical parameters in estimating land surface temperature & heat fluxes diurnally in summer and winter seasons of years 2000 and 2010 and understanding its effect on anthropogenic heat disturbance over Delhi and surrounding region. Results show that during years 2000-2010, settlement and industrial area increased from 5.66 to 11.74% and 4.92 to 11.87% respectively which in turn has direct effect on land surface temperature (LST) and heat fluxes including anthropogenic heat flux. Based on the energy balance model for land surface, a method to estimate the increase in anthropogenic heat flux (Has) has been proposed. The settlement and industrial areas has higher amounts of energy consumed and has high values of Has in all seasons. The comparison of satellite derived LST with that of field measured values show that Landsat estimated values are in close agreement within error of ±2 °C than MODIS with an error of ±3 °C. It was observed that, during 2000 and 2010, the average change in surface temperature using Landsat over settlement & industrial areas of both seasons is 1.4 °C & for MODIS data is 3.7 °C. The seasonal average change in anthropogenic heat flux (Has) estimated using Landsat & MODIS is up by around 38 W/m(2) and 62 W/m(2) respectively while higher change is observed over settlement and concrete structures. The study reveals that the dynamic range of Has values has increased in the 10 year period due to the strong anthropogenic influence over the area. The study showed that anthropogenic heat flux is an indicator of the strength of urban heat island effect, and can be used to quantify the magnitude of the urban heat island effect.
表面能量过程在城市天气、气候和水圈循环中起着重要作用，也在城市热量再分配中起着重要作用。本研究旨在分析 Landsat 和 MODIS 数据在夏季和冬季 2000 年和 2010 年期间获取生物物理参数、估算地表温度和热通量的潜力，以及了解其对德里及其周边地区人为热干扰的影响。结果表明，在 2000 年至 2010 年期间，居住和工业区域分别从 5.66%增加到 11.74%和从 4.92%增加到 11.87%，这直接影响到地表温度（LST）和热通量，包括人为热通量。基于陆地表面能量平衡模型，提出了一种估算人为热通量（Has）增加的方法。居住和工业区域消耗的能量较多，在所有季节的人为热通量都较高。卫星反演的 LST 与实地测量值的比较表明，Landsat 估算值与 MODIS 的误差在±2°C 以内，误差为±3°C。研究发现，在 2000 年和 2010 年，使用 Landsat 对两个季节的居住和工业区域的地表温度平均变化分别为 1.4°C，而使用 MODIS 数据的平均变化为 3.7°C。使用 Landsat 和 MODIS 估算的季节性平均人为热通量（Has）变化分别增加了约 38 W/m²和 62 W/m²，而在居住和混凝土结构区域观察到的变化更大。研究表明，由于该地区受到强烈的人为影响，人为热通量的动态范围在 10 年内有所增加。该研究表明，人为热通量是城市热岛效应强度的一个指标，可以用来量化城市热岛效应的大小。
