Remote sensing of the urban heat island effect across biomes in the continental USA

Abstract

Impervious surface area (ISA) from the Landsat TM-based NLCD 2001 dataset and land surface temperature (LST) from MODIS averaged over three annual cycles (2003)(2004)(2005) are used in a spatial analysis to assess the urban heat island (UHI) skin temperature amplitude and its relationship to development intensity, size, and ecological setting for 38 of the most populous cities in the continental United States. Development intensity zones based on %ISA are defined for each urban area emanating outward from the urban core to the nonurban rural areas nearby and used to stratify sampling for land surface temperatures and NDVI. Sampling is further constrained by biome and elevation to insure objective intercomparisons between zones and between cities in different biomes permitting the definition of hierarchically ordered zones that are consistent across urban areas in different ecological setting and across scales. We find that ecological context significantly influences the amplitude of summer daytime UHI (urban-rural temperature difference) the largest (8°C average) observed for cities built in biomes dominated by temperate broadleaf and mixed forest. For all cities combined, ISA is the primary driver for increase in temperature explaining 70% of the total variance in LST. On a yearly average, urban areas are substantially warmer than the non-urban fringe by 2.9°C, except for urban areas in biomes with arid and semiarid climates. The average amplitude of the UHI is remarkably asymmetric with a 4.3°C temperature difference in summer and only 1.3°C in winter. In desert environments, the LST's response to ISA presents an uncharacteristic "U-shaped" horizontal gradient decreasing from the urban core to the outskirts of the city and then increasing again in the suburban to the rural zones. UHI's calculated for these cities point to a possible heat sink effect. These observational results show that the urban heat island amplitude both increases with city size and is seasonally asymmetric for a large number of cities across most biomes. The implications are that for urban areas developed within forested ecosystems the summertime UHI can be quite high relative to the wintertime UHI suggesting that the residential energy consumption required for summer cooling is likely to increase with urban growth within those biomes.Published by Elsevier Inc.

Spatiotemporal Assessment of Vegetation Indices and Land Cover for Erbil City and Its Surrounding Using Modis Imageries

“…The impacts may become pronounced when they interact on a global scale. Therefore a better understanding of the effect of urbanization is required to support greener sustainable development and climate change strategies (Imhoff et al, 2010). Possible solutions include the creation of green spaces, that are irrigated and fertilized, which are found to considerably reduce the negative consequences associated with transformation into urban environment (Gregg et al, 2003).…”

Application of a new integrated landscape index to predict potential urban heat islands

“…The LST is the mean radiative skin temperature, determined by air temperature and long-wave radiation between the surface and the atmosphere (Nichol et al, 2009;Weng, 2009). Unlike air temperature, LST has a higher spatial resolution and relates more closely to surface land use or landscape pattern, which can easily be derived from remote sensing data (Imhoff et al, 2010;Voogt and Oke, 2003;Weng, 2009). Thus, surface UHI and its associated data source, LST, have been increasingly used in the study of urban climate in recent decades (EPA, 2009;Mirzaei and Haghighat, 2010).…”

基于遥感监测的城市热岛研究进展

“…由于 LST 显著与土地覆盖相关， 以往不少研究 首先主要基于土地覆盖并同时考虑距离城区的空 间距离、 地形等确定 "城市" 、 "郊区" 或 "乡村" 的范 围， 然后计算城市或城市核心区与周边乡村 (Dan et al, 2010;Imhoff et al, 2010;Tomlinson et al, 2012;Clinton et al, 2013;Haashemi et al, 2016 Abstract: Rapid and high intensity urbanization is currently occurring in the world, resulting in increasingly more serious urban heat island phenomenon. Urban heat islands have direct and indirect impacts on various ecoenvironment factors of cities, regions, and the world, which are closely related to the human well-being.…”