Overestimating Impacts of Urbanization on Regional Temperatures in Developing Megacity: Beijing as an Example

Abstract

Land-use and land cover changes may have important local, regional, and global climatic impacts by modifying the underlying land surface conditions, which in turn influence the exchange of energy and moisture between the land surface and atmosphere. Many studies have shown that urbanization has contributed to climate warming, and the amount of warming has varied. As the capital of China and one of the world’s megacities, Beijing has experienced rapid urbanization over the past 30 years. In this study, we quantitatively investigated the impacts of urbanization on regional temperatures based on observations from meteorological stations and National Centers for Environmental Prediction (NCEP) reanalysis data and overestimating of the impacts were found. Comparing the temperature trends of land-use types, forest showed stronger inhibitory effects on temperature increase (−0.085°C/10a). Cropland also had a negative effect on climate warming yearly and seasonally, especially in winter (−1.133°C/10a) and spring (−0.299°C/10a). Conversely, the urban area showed strong warming effects (0.438°C/10a). The conversion of cropland to urban land appeared to show the highest warming trend (0.548°C/10a). However, the cooling effect of forest and grassland with high vegetation coverage inhibited climatic warming attributed to rapid urbanization. In addition, planting trees or grass along roadsides and increasing green parks and green roofs can also suppress surface warming. Therefore, the actual warming effects of urbanization on temperatures were overestimated in megacities or urban agglomeration regions. The results showed that the green space and landscape configuration should be considered in urban planning to increase green space and reduce the influence of urban heat island effect.

Spatiotemporal shifts in thermal climate in responses to urban cover changes: a-case analysis of major cities in Punjab, Pakistan

“…The thermal physics of the built-up cover was also explained to SUHII by keeping in mind the thermal conductivity of the material, the basic heat power of the material, and thermal conduction, etc. (Chapin et al 2005). The LULC modifications in the rural buffer could clarify this.…”

“…Urban cover will occupy 66 percent of the land cover globally and it boosts the LST and urban heat. (Yang et al 2017, Cao et al 2019. Urban LST is associated with LULC changes in tropical and sub-tropical climate regions.…”

Remote Sensing-Based Quantification of the Relationships between Land Use Land Cover Changes and Surface Temperature over the Lower Himalayan Region

“…Tropical and sub-tropical climate urban areas LST depend on LULC, where built-up areas have the highest LST in comparison with arid environments in which bare soil had the highest LST [8,9]. Urban warming increased air temperature in the Himalayan region by affecting humidity and temperature of the lower boundary layer of air [10,11]. Also, the increase in LST regimes would cause the formation of an UHI [12].…”

Modelling of Land Use/Cover and LST Variations by Using GIS and Remote Sensing: A Case Study of the Northern Pakhtunkhwa Mountainous Region, Pakistan

“…The projected results indicate the rising drift (409 Km 2 ) in the higher-temperature zone (i.e., 27 to <30 • C), whereas the lower-temperature zone in range of (i.e., 12 to <21 • C) showed a decreasing trend, which is (42 Km 2 ). Several elements such as global warming, greenhouse gases, and changes in surface features directly or indirectly affect the LST of the area [68,69]. Similarly, the expansion in built-up areas may also be the reason for the expansion in temperature [70].…”