Urban heat island in the subsurface

Abstract

The urban heat island effect has received significant attention in recent years due to the possible effect on long‐term meteorological records. Recent studies of this phenomenon have suggested that this may not be important to estimates of regional climate change once data are properly corrected. However, surface air temperatures within urban environments have significant variation, making correction difficult. In the current study, we examine subsurface temperatures in an urban environment and the surrounding rural area to help characterize the nature of this variability. The results of our study indicate that subsurface temperatures are linked to land‐use and supports previous work indicating that the urban heat island effect has significant and complex spatial variability. In most situations, the relationship between subsurface and surface processes cannot be easily determined, indicating that previous studies that relying on such a linkage may require further examination.

Localized Climate and Surface Energy Flux Alterations across an Urban Gradient in the Central U.S.

“…Other site maintenance related issues (sensor degradation, debris, mowing) may have contributed to data trend inconsistencies. Despite vegetation (crop types) and management related cover differences (assumed a negligible effect over long-term), soil temperature data showed a gradient (5 cm depth: 14.75 and 14.07 °C for Sanborn and South Farm, respectively; 10 cm depth: 14.63 and 14.25 °C for Sanborn and South Farm, respectively) between rural and urban temperatures which was correlated with the air temperature gradient (13.47 and 12.89 °C of Sanborn and South Farm, respectively), and similarly equivalent attenuation of surface heating with increasing depth, consistent with results of previous studies [20,22,30,32]. Ferguson and Woodbury emphasized in 2007 that temperature effects of UHI at the surface are positively correlated with temperature effects of UHI at the subsurface [21].…”

“…Urban areas with elevated air temperatures resulting from UHI exhibit higher subsurface temperatures than rural areas [21]. The increase in subsurface temperature is a result of conduction of surface heat, and the effects may continue downward for several meters into the soil [22]. The extent and depth of soil heating is highly dependent on soil thermal properties, which are influenced by soil structure and texture and are therefore often highly variable between sites [21].…”

Changes in regional meteorology induced by anthropogenic heat and their impacts on air quality in South China

“…The maximum T 2 changes are usually found in the city centers of the PRD region, with typical increments of over 1.1 • in January and of over 0.5 • in July. These findings are comparable to the values estimated for other cities (Fan and Sailor, 2005;Ferguson and Woodbury, 2007;Zhu et al, 2010;Menberg et al, 2013;Wu and Yang, 2013;Bohnenstengel et al, 2014;Yu et al, 2014;Xie et al, 2016) and can be confirmed by similar research in South China (Meng et al, 2011;Feng et al, 2012Feng et al, , 2014. Figure 4e and f present the vertical changes in air temperature from the surface to the 800 hPa layer along the line AB (shown in Fig.…”

“…Sometimes, the fluxes might exceed the value of 100 W m −2 (Iamarino et al, 2012;Quah and Roth, 2012;Lu et al, 2016;Xie et al, 2016), with the extreme value of 1590 W m −2 in the densest part of Tokyo at the peak of air-conditioning demand (Ichinose et al, 1999). With regard to their effects, the researchers found that AH fluxes can cause urban air temperatures to increase by several degrees (Fan and Sailor, 2005;Ferguson and Woodbury, 2007;Zhu et al, 2010;Feng et al, 2012Feng et al, , 2014Menberg et al, 2013;Wu and Yang, 2013;Bohnenstengel et al, 2014;Chen et al, , 2014aYu et al, 2014;Xie et al, 2016), induce the atmosphere to be more turbulent and unstable, change the urban heat island circulation, strengthen vertical air movement (Ichinose et al, 1999;Block et al, 2004;Fan and Sailor, 2005;Feng et al, 2012Feng et al, , 2014Bohnenstengel et al, 2014;Yu et al, 2014;Xie et al, 2016), enhance the convergence of water vapor in cities, and change the regional precipitation patterns (Feng et al, 2012(Feng et al, , 2014Xie et al, 2016). In spite of meteorology conditions and air quality being inextricably linked, however, few investigations have paid attention to how the air quality is altered by the changes in regional meteorology induced by anthropogenic heat.…”

“…Anthropogenic heat (AH) can increase turbulent fluxes in sensible and latent heat (Oke, 1988), implying that it can modulate local and regional meteorological processes (Ichinose et al, 1999;Block et al, 2004;Fan and Sailor, 2005;Ferguson and Woodbury, 2007;Zhu et al, 2010;Feng et al, 2012Feng et al, , 2014Menberg et al, 2013;Ryu et al, 2013;Wu and Yang, 2013;Bohnenstengel et al, 2014;Chen et al, 2014a;Meng et al, 2011;Yu et al, 2014;Xie et al, 2016) and thereby exert an important influence on the formation and the distribution of ozone (Ryu et al, 2013;Yu et al, 2014;Xie et al, 2016) as well as aerosols (Yu et al, 2014;Xie et al, 2016).…”