Document Type
Article
Publication Date
8-3-2021
Publication Title
Remote Sensing
Publisher
MDPI
Volume
13
Issue
15
First page number:
1
Last page number:
23
Abstract
Urbanization increases the amount of impervious surfaces, making accurate information on spatial and temporal expansion trends essential; the challenge is to develop a cost-and laboreffective technique that is compatible with the assessment of multiple geographical locations in developing countries. Several studies have identified the potential of remote sensing and multiple source information in impervious surface quantification. Therefore, this study aims to fuse datasets from the Sentinel 1 and 2 Satellites to map the impervious surfaces of nine Pakistani cities and estimate their growth rates from 2016 to 2020 utilizing the random forest algorithm. All bands in the optical and radar images were resampled to 10 m resolution, projected to same coordinate system and geometrically aligned to stack into a single product. The models were then trained, and classifications were validated with land cover samples from Google Earth’s high-resolution images. Overall accuracies of classified maps ranged from 85% to 98% with the resultant quantities showing a strong linear relationship (R-squared value of 0.998) with the Copernicus Global Land Services data. There was up to 9% increase in accuracy and up to 12 % increase in kappa coefficient from the fused data with respect to optical alone. A McNemar test confirmed the superiority of fused data. Finally, the cities had growth rates ranging from 0.5% to 2.5%, with an average of 1.8%. The information obtained can alert urban planners and environmentalists to assess impervious surface impacts in the cities.
Keywords
Data fusion; Impervious surface extraction and mapping; Land cover classification; Pakistani cities; Random forest classifier; Sentienel-2 MSI; Sentinel-1 SAR; Sustainable Development Goals
Disciplines
Architecture | Urban, Community and Regional Planning
File Format
File Size
11268 KB
Language
English
Rights
IN COPYRIGHT. For more information about this rights statement, please visit http://rightsstatements.org/vocab/InC/1.0/
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
Repository Citation
Shrestha, B.,
Stephen, H.,
Ahmad, S.
(2021).
Impervious Surfaces Mapping at City Scale by Fusion of Radar and Optical Data Through a Random Forest Classifier.
Remote Sensing, 13(15),
1-23.
MDPI.
http://dx.doi.org/10.3390/rs13153040