Impact of Rapid Urban Sprawl on the Local Meteorological Observational Environment Based on Remote Sensing Images and GIS Technology

Yanhao Zhang,Yuanjian Yang,Shihan Chen,Guicai Ning

doi:10.3390/rs13132624

Abstract

Rapid increases in urban sprawl affect the observational environment around meteorological stations by changing the land use/land cover (LULC) and the anthropogenic heat flux (AHF). Based on remote sensing images and GIS technology, we investigated the impact of changes in both LULC and AHF induced by urbanization on the meteorological observational environment in the Yangtze River Delta (YRD) during 2000–2018. Our results show that the observational environments around meteorological stations were significantly affected by the rapid expansion of built-up areas and the subsequent increase in the AHF, with a clear spatiotemporal variability. A positive correlation was observed between the proportion of built-up areas and the AHF around meteorological stations. The AHF was in the order urban stations > suburban stations > rural stations, but the increases in the AHF were greater around suburban and rural stations than around urban stations. Some meteorological stations need to be relocated to address the adverse effects induced by urbanization. The proportion of built-up areas and AHF around the new stations decreased significantly after relocation, weakening the urban heat island effect on the meteorological observations and substantially improving the observational environment. As a result, the observed daily mean temperature (relative humidity) decreased (increased) around the new stations after relocation. Our study comprehensively shows the impact of rapid urban sprawl on the observational environment around meteorological stations by assessing changes in both LULC and the AHF induced by urbanization. These findings provide scientific insights for the selection and construction of networks of meteorological stations and are therefore helpful in scientifically evaluating and correcting the impact of rapid urban sprawl on meteorological observations.

Highlights

With the rapid increases in urban sprawl and economic development in China over the last 20 years, a large number of meteorological stations have gradually become surrounded by urban areas and many of them are located in city centers
Taking the meteorological stations located in four provincial cities as examples, we can see that the urbanization process was significantly different at each station (Figure 2)
We comprehensively investigated the impact of rapid urban sprawl on the observa5

Summary

Introduction

With the rapid increases in urban sprawl and economic development in China over the last 20 years, a large number of meteorological stations have gradually become surrounded by urban areas and many of them are located in city centers This has led to changes in the land use/land cover (LULC) around stations [1] and a deterioration in the representativeness of the meteorological observational environment [2]. Previous studies of regional climate change and urbanization effects usually distinguished urban and rural stations based on the population of the surrounding area and used the results in comparative analyses of the temperature elements [11] This discrimination method does not consider factors such as whether the station is located within the city, the natural conditions around the station or the characteristics of the underlying surface [12]. Satellite data can provide accurate and extensive real-time information about changes at meteorological stations and in the surrounding observational environment, facilitate the accurate classification of stations and effectively reproduce historical environmental changes such as changes in LULC around stations [16,17]

Methods

Results

Discussion

Conclusion