An Urban Heat Island Study of the Colombo Metropolitan Area, Sri Lanka, Based on Landsat Data (1997–2017)
One of the major impacts associated with unplanned rapid urban growth is the decrease of urban vegetation, which is often replaced with impervious surfaces such as buildings, parking lots, roads, and pavements. Consequently, as the percentage of impervious surfaces continues to increase at the expen...
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| Format: | Article |
| Language: | English |
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MDPI AG
2017-06-01
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| Series: | ISPRS International Journal of Geo-Information |
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| Online Access: | http://www.mdpi.com/2220-9964/6/7/189 |
| _version_ | 1811313459423346688 |
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| author | Manjula Ranagalage Ronald C. Estoque Yuji Murayama |
| author_facet | Manjula Ranagalage Ronald C. Estoque Yuji Murayama |
| author_sort | Manjula Ranagalage |
| collection | DOAJ |
| description | One of the major impacts associated with unplanned rapid urban growth is the decrease of urban vegetation, which is often replaced with impervious surfaces such as buildings, parking lots, roads, and pavements. Consequently, as the percentage of impervious surfaces continues to increase at the expense of vegetation cover, surface urban heat island (SUHI) forms and becomes more intense. The Colombo Metropolitan Area (CMA), Sri Lanka, is one of the rapidly urbanizing metropolitan regions in South Asia. In this study, we examined the spatiotemporal variations of land surface temperature (LST) in the CMA in the context of the SUHI phenomenon using Landsat data. More specifically, we examined the relationship of LST with the normalized difference vegetation index (NDVI) and the normalized difference built-up index (NDBI) at three time points (1997, 2007 and 2017). In addition, we also identified environmentally critical areas based on LST and NDVI. We found significant correlations of LST with NDVI (negative) and NDBI (positive) (p < 0.001) across all three time points. Most of the environmentally critical areas are located in the central business district (CBD), near the harbor, across the coastal belt, and along the main transportation network. We recommend that those identified environmentally critical areas be considered in the future urban planning and landscape development of the city. Green spaces can help improve the environmental sustainability of the CMA. |
| first_indexed | 2024-04-13T10:55:17Z |
| format | Article |
| id | doaj.art-214eaa4cdac74427bec3554d4474a4e5 |
| institution | Directory Open Access Journal |
| issn | 2220-9964 |
| language | English |
| last_indexed | 2024-04-13T10:55:17Z |
| publishDate | 2017-06-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | ISPRS International Journal of Geo-Information |
| spelling | doaj.art-214eaa4cdac74427bec3554d4474a4e52022-12-22T02:49:33ZengMDPI AGISPRS International Journal of Geo-Information2220-99642017-06-016718910.3390/ijgi6070189ijgi6070189An Urban Heat Island Study of the Colombo Metropolitan Area, Sri Lanka, Based on Landsat Data (1997–2017)Manjula Ranagalage0Ronald C. Estoque1Yuji Murayama2Faculty of Life and Environmental Sciences, University of Tsukuba 1-1-1 Tennodai, Tsukuba City, Ibaraki 305-8572, JapanFaculty of Life and Environmental Sciences, University of Tsukuba 1-1-1 Tennodai, Tsukuba City, Ibaraki 305-8572, JapanFaculty of Life and Environmental Sciences, University of Tsukuba 1-1-1 Tennodai, Tsukuba City, Ibaraki 305-8572, JapanOne of the major impacts associated with unplanned rapid urban growth is the decrease of urban vegetation, which is often replaced with impervious surfaces such as buildings, parking lots, roads, and pavements. Consequently, as the percentage of impervious surfaces continues to increase at the expense of vegetation cover, surface urban heat island (SUHI) forms and becomes more intense. The Colombo Metropolitan Area (CMA), Sri Lanka, is one of the rapidly urbanizing metropolitan regions in South Asia. In this study, we examined the spatiotemporal variations of land surface temperature (LST) in the CMA in the context of the SUHI phenomenon using Landsat data. More specifically, we examined the relationship of LST with the normalized difference vegetation index (NDVI) and the normalized difference built-up index (NDBI) at three time points (1997, 2007 and 2017). In addition, we also identified environmentally critical areas based on LST and NDVI. We found significant correlations of LST with NDVI (negative) and NDBI (positive) (p < 0.001) across all three time points. Most of the environmentally critical areas are located in the central business district (CBD), near the harbor, across the coastal belt, and along the main transportation network. We recommend that those identified environmentally critical areas be considered in the future urban planning and landscape development of the city. Green spaces can help improve the environmental sustainability of the CMA.http://www.mdpi.com/2220-9964/6/7/189urban heat islandland surface temperatureNDVINDBIEnvironmental Criticality IndexColombo Metropolitan Area |
| spellingShingle | Manjula Ranagalage Ronald C. Estoque Yuji Murayama An Urban Heat Island Study of the Colombo Metropolitan Area, Sri Lanka, Based on Landsat Data (1997–2017) ISPRS International Journal of Geo-Information urban heat island land surface temperature NDVI NDBI Environmental Criticality Index Colombo Metropolitan Area |
| title | An Urban Heat Island Study of the Colombo Metropolitan Area, Sri Lanka, Based on Landsat Data (1997–2017) |
| title_full | An Urban Heat Island Study of the Colombo Metropolitan Area, Sri Lanka, Based on Landsat Data (1997–2017) |
| title_fullStr | An Urban Heat Island Study of the Colombo Metropolitan Area, Sri Lanka, Based on Landsat Data (1997–2017) |
| title_full_unstemmed | An Urban Heat Island Study of the Colombo Metropolitan Area, Sri Lanka, Based on Landsat Data (1997–2017) |
| title_short | An Urban Heat Island Study of the Colombo Metropolitan Area, Sri Lanka, Based on Landsat Data (1997–2017) |
| title_sort | urban heat island study of the colombo metropolitan area sri lanka based on landsat data 1997 2017 |
| topic | urban heat island land surface temperature NDVI NDBI Environmental Criticality Index Colombo Metropolitan Area |
| url | http://www.mdpi.com/2220-9964/6/7/189 |
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