Spatiotemporal Variability Analysis of Weather Parameters in Chittagong City Corporation, Bangladesh From 1990 to 2020

Abstract

The present study explores the spatiotemporal variability of weather parameters in the Chittagong City Corporation (CCC) areas in Chittagong, Bangladesh. The current research was initially focused on understanding the dominant weather parameter changes (such as rainfall, air temperature, and relative humidity) from 1990 to 2020 weather data using geographic information system (GIS) and statistical analysis. The GIS map was prepared in four seasons (i.e., MAM, JJA, SON, and DJF) using Bangladesh Meteorological Department (BMD) data which considered the Co-Kriging interpolation technique in ArcGIS 10.8 software. An equal interval break classification with five (5) classes method was employed to classify each image. Further, the annual trend analysis was performed using the Mann-Kendall trend including Sen’s slope estimator statistical analyses to support the present study. The study result reveals that the rainfall of CCC areas decreased in JJA among all seasons by 165.8mm in 2020 compared to 1990, whereas the annual trend of average rainfall also suggested the same. In CCC, overall, the seasonal air temperature in JJA from 1990 to 2020 rose by 3.3°C. In contrast, the data on relative humidity in JJA also observed an increasing trend (33.6%) during the same period. Meanwhile, the mean annual air temperature scenario has risen 1.1°C, and relative humidity decreased by 1.5% from 1990 to 2020. The outcome of this study will help researchers and city planners to understand the climate change thus helping to ensure the CCC becomes healthy, economically viable, resilient, and sustainable.