Shoreline changes over last five decades and predictions for 2032 and 2042: a case study of Kakinada coast, Southeast coast of India

This study conducted a comprehensive analysis of erosion and accretion rates in the Kakinada coastal zones of Andhra Pradesh using multitemporal satellite images spanning six time periods from 1972 to 2022. Two methods, End Point Rate (EPR) and Linear Regression Rate (LRR), were employed to assess erosion and accretion, revealing maximum erosion rates of -28.64 and - 31.27 m/year and maximum accretion rates of 20.11 and 22.74 m/year in the study area. These changes were attributed to natural disasters like tsunamis and cyclones and anthropogenic activities such as harbour construction, beach sand excavation, industrialization of garbage dump sites, urbanization, and domestic sewage discharge. Further analysis, using the Kalman filter model, forecasted shoreline changes, predicting erosion of -842 and - 891 m and accretion of 700 and 679 m in 2032 and 2042, respectively. Specific erosion zones were identified near Uppada, Gadimoga, and Korangi, while accretion was predominant in Kakinada, Nadakuduru, Kovvadda, and Panasapadu regions. The use of multitemporal satellite images and analytical methods highlights the crucial role of spatial information science in tracking long-term coastal changes and assessing localized erosion and accretion dynamics. These findings provide the tools for effective decision-making in safeguarding vulnerable shorelines amidst evolving environmental and human-induced challenges.