Urban Growth and Multi-seasonal Land Cover Classification of Dhaka, Bangladesh: An Approach Using Google Earth Engine

Abstract

Land cover change strongly influences environmental change and local climate variability and therefore can tamper with improvements in local, regional, and global policies. Cities of the world with rapid land cover and demographic change require strong adaptation and mitigation policies to maintain a healthy environment. One such global city is Dhaka, the capital of BangladeshLand Cover and Land Use (LCLU)Dhaka, Bangladesh and the third most densely populated city in the world. Dhaka has grown uncontrollably, creating many economic, logistic, and environmental challenges. To quantify the growth of Dhaka city and assess the impact of land cover changes on the environment, the popular and traditional method of overlaying anniversary remotely sensed images was implemented. Twenty-four Landsat images for each year were overlaid, covering ten years from 2008 to 2018 with a 5-year interval (2008, 2013, 2018) using the Google Earth EngineLand Cover and Land Use (LCLU)Google Earth Engine (GEE), importance of tool, to assess and quantify the land use and land coverLand Cover and Land Use (LCLU)land cover changes of Dhaka. The classificationLand Cover and Land Use (LCLU)land cover and regression tree (CART)Land Cover and Land Use (LCLU)Classification and Regression Tree (CART) algorithm was used to classify the land cover. The study highlighted that except for urban built-upDhaka, Bangladeshurban built-up, which had a 16% steady increase over the ten years, all other categories showed dips and rises. The ten-year expansion pattern shows that initially, the growth was close to Buriganga River, but gradually, the city expanded to the north and east, away from the river. We believe that our research approach provides better insight into a multi-seasonal land cover classification for planners and policymakers to utilize in city improvements.