A 35-year analysis found persistent erosion and an average shoreline loss of 90 metres in the Indian village.
Researchers combined satellite images, elevation and sea-level data, land-use mapping and field observations to assess coastal vulnerability in Visakhapatnam and Uppada Village. They examined shoreline change, coastal slope, land use and land cover, relative sea level, and tidal range across five time periods between 1990 and 2024.
Uppada showed consistent erosion, with no notable accretion to offset the loss. Visakhapatnam had both erosion and shoreline growth in different areas, with a net average retreat of 64 metres over the study period. The researchers say the results provide baseline information for coastal adaptation and conservation planning.
Erosion at both sites
Uppada Village was identified as a highly vulnerable coastal zone. Its erosion rate reached 3.95 metres per year, and the shoreline moved inland by an average of 90 metres between 1990 and 2024. The researchers found no notable accretion there and linked the vulnerability assessment to wave action, sea-level rise, the village’s low-lying unprotected coastline, and the lack of natural protective features.
Visakhapatnam had a more uneven pattern. Some areas eroded at up to 13.1 metres per year, while others gained shoreline at rates of up to 21.1 metres per year. Overall, its coastline retreated by an average of 64 metres during the study period. The study attributes vulnerability there to a combination of human activity and natural coastal processes.
Why Uppada stands out
The findings identify Uppada as a coastline where continued erosion could cause severe degradation within the next two or three decades if the reported rate persists. The researchers say the results can help government agencies, coastal managers and other stakeholders plan adaptation measures, including engineered protections and nature-based approaches such as mangrove restoration and seagrass development.
The comparison also shows that different places may require different responses: the study links Visakhapatnam’s vulnerability partly to port infrastructure and urban expansion, while it describes Uppada as a naturally exposed, unprotected coastline.
Evidence and caveats
The study used Landsat satellite imagery from 1990 to 2024, elevation data, sea-level records, tidal information and land-use mapping. Researchers assessed five physical factors with geographic information system tools and checked the results through field visits and georeferenced photographs.
The shoreline positions derived from the 30-metre satellite images have an estimated uncertainty of about plus or minus 15 metres. Images could not always be selected from the same tidal phase, and the five analysis dates may miss erosion or accretion caused by storms and cyclones between observations. Transect spacing and baseline placement can also affect shoreline-change estimates, and the most extreme local rates may be influenced by human-built structures. The study does not include future climate projections, detailed modelling of changes in cyclone activity, or social vulnerability indicators.
// Source
Marine Development · 2026 · DOI: 10.1007/s44312-026-00088-3
Authors: Komali Kantamaneni, Ruchiru Dilshan Herath, Robert Walsh, Swarnalatha Purushotham, Sreenivasulu Vemu, Luiza C. Campos, Upaka Rathnayake
Institutions: University College London, Vellore Institute of Technology University, Atlantic Technological University, University of Lancashire, Jawaharlal Nehru Technological University, Kakinada
