Abstract

Major metropolitan (tier I) Indian cities have been experiencing rapid urbanisation during the last two decades with globalization and changes in Indian market. These unprecedented market interventions have led to rapid urban expansions with drastic land cover changes affecting the ecology, climate, hydrology and local environment. Unplanned rapid urbanisation in some cities has given way to the dispersed, haphazard growth at city outskirts. These regions lack basic amenities and infrastructure as the planners lack advance information of sprawl regions. This has necessitated understanding and visualization of urbanisation patterns for planning towards sustainable cities. Temporal availability of spatial data at regular intervals through space borne remote sensors coupled with the recent advances in geo-informatics aids in the advance geo- visualization of spatial patterns of urban growth. The urban expansion and the urban growth dynamics elucidated for four major metros of India, using temporal remote sensing data through density gradient approach and pre-validated spatial metrics. The current communication provides vital insights to the intra and inter spatio-temporal patterns of urbanisation across four rapidly urbanising metropolitan cities in India. Analyses of intra spatial patterns reveal that inner gradients (in the vicinity of central business district) have reached the threshold of urbanisation. Landscape metrics highlight the process of aggregation through clumping of patches to form a dominant urban patch with complex to simple shapes and highly domination urban class. Further, Principal component analyses (PCA) highlight that buffer regions are influenced by patches with complex shaped multi class growth, while core city centers have a simple shaped clumped growth.

Keywords: Urbanization, urban growth, spatial metrics, Principal Component Analysis, density gradients