Document Type : Original Article

Authors

• Alireza Khorram ¹
• Maryam Yusefi ²
• Mehdi Fardad ³

¹ Health Promotion Research Center, Zahedan University of Medical Sciences, Zahedan, Iran

² Young Researchers and Elites Club, Birjand Branch, Islamic Azad University of Birjand, Birjand, Iran

³ Department of Civil Engineering, Islamic Azad University of Behbahan, Behbahan, IR, Iran

Abstract

Aims: The first aim of this study was to estimating the percentage of land area that was affected by various levels of light pollution and secondary aim is to assess the light pollution growth. Materials and Methods: This study describes a methodology for modeling light pollution in Bojnord city, using geographical information systems and remote sensing technology. The Defense Meteorological Satellite Program-Operational Linescan System (DMSP-OLS) and Landsat TM⁵ images in 1991, 1999, 2005 and 2012 were used. The DMSP-OLS images were classified to six categories from null to very high. The Landsat images were applied in order to calculate the urban area and extraction urban border in 4 years. Results: The results were showed that the light pollution area (km²) in very high category has increased 10.34, 2.73 and 15.94 km² of the entire study area from 1991-1998, 1998-2005 and 2005-2012, respectively. While, in that periods of time, the null category area (km²) declined 23.19, 21.97 and 100.36 km², respectively. In 2005 and 2012 about 92.8% and 86% of the total study area has been in the Null class. There was a direct association between urbanization, spatial development of urban areas and light pollution growth. Conclusions: One of the main reason for light pollution growth is declaring this region as capital city in 2005 and consequently, urban development and population emigration to capital.

Keywords

• Bojnord
• Defense Meteorological Satellite Program-Operational Linescan System geographical information systems
• light pollution
• urbanization