Assessment of urbanisation and urban heat island intensities using landsat imageries during 2000 – 2018 over a sub-tropical Indian City

Abstract

Rapid urbanization and expansion of cities have a significant impact on the climate. It is essential to understand the impact of the land use land cover changes (LULC) on the regional climate variations over cities. This work mainly focuses on the changes in hotspot zones, UHIs during two different seasons - winter and summer. An attempt has been made to study the spatiotemporal variation in the urban heat islands (UHIs) and their relationship with LULC during 2000–2018, over Chandigarh (30° 43′ 59″ N, 76° 46′ 46″ E), a planned sub-tropical Indian city, using the remote sensing techniques. The indices such as Enhanced Built-up and Bareness Index (EBBI), Dry Built-up Index (DBI) and Dry Bare-Soil Index (DBSI) are employed to differentiate the built-up areas (BA) from the drylands (DL) effectively. The changes observed in the LULC reveals an increase of 10% in the BA at the expense of the vegetation during 2000–2018, which is in close agreement with the EBBI, DBI and DBSI assessments. A steady increase is observed in the UHI intensities for both summer and winter seasons during the study period. The UHIindex is noticed to be higher for the DL than that of the BA.