Abstract
The Greater Cairo Region (GCR), Egypt has experienced rapid urban expansion and broad development over the past several decades. Due to such development, this region faces many environmental consequences. In order to mitigate such consequences, it is essential to examine the historical change to measure the urban sprawl of GCR, and its effect on land surface temperature (LST). The objective of this study is to fulfill this goal. It does so by generating land use/land cover (LULC) maps derived from Landsat 5 TM for 1990 and 2003 and Landsat 8 OLI for 2016, using several classification techniques. A spectral radiance model and a web-based atmospheric correction model were used to successfully evaluate LST from thermal bands of Landsat data. Overall accuracy of Landsat derived land use data were 90.3%, 96.5% and 94.9% for years 1990, 2003 and 2016, respectively. The LULC change analysis revealed vegetation loss to urban land by an amount of 7.73% and from barren lands to urban uses by 8.70% within a 26-year timespan (1990-2016). This rapid urban growth significantly decreases vegetation areas, consequently increasing the LST and modifying the urban microclimate. Results from this study can help policy-makers characterize the evolution of urban construction for future developments.
Highlights
Cities are dynamic due to unavoidable changes that can be assigned to many factors
The current study aims to: 1) quantitatively delineate different land use/land cover (LULC) classes and evaluate the pattern of LULC change from 1990 to 2016 in Greater Cairo Region (GCR); 2) provide tools to reliably investigate the variation of land surface temperature (LST) values in relation to LULC change through time; 3) further evaluate the effect of vegetation on LST as derived from different algorithms for satellite imagery through an examination of the Normalized Different Vegetation Index (NDVI)-LST and (Normalized Different Built-up Index) NDBI-LST correlation based on statistical analysis methods and the texture of LULC changes, to determine the main causes of these environmental changes; and 4) examine the potential and the accuracy of Remote sensing (RS) and Geographic Information Systems (GIS) utilization in monitoring the spatial distribution of LULC changes
Spatial distribution patterns reveal that the area was dominated by deserts and barren lands, vegetation in the northern region and urban cover in the middle
Summary
Cities are dynamic due to unavoidable changes that can be assigned to many factors. One of the main factors behind these changes is urban growth and population expansion [1]. A seeming lack of planning of land use/land cover (LULC) has been a problem at a local and regional scale, making it a major issue in the study of worldwide ecological change [2] [3] [4]. Such changes have many implications for human society, environmental resilience, and water issues, such as the alteration of runoff, infiltration and groundwater discharge [5]. The impact on environmental processes cannot be well-understood and mitigated without understanding the impacts of climate change, the interaction between the earth and the atmosphere and knowledge of land use/land cover change at various scales that drive them [2]
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have