Vulnerability and Adaptation to Climate Change in the Indian Sundarban Delta

This study explores the significant effects of climate change on the low-lying islands of the Indian Sundarban Delta (ISD), an area recognized for its high vulnerability within South Asia. The ISD covers approximately 10,200 km² across India and Bangladesh and is characterized by islands rising less than five meters above sea level, formed from ancient sedimentary deposits. These distinctive geographic features, coupled with the region’s dense mangrove forests—which represent most India’s mangrove habitats—make the ISD particularly sensitive to climate-driven disturbances. Local communities whose livelihoods depend on fishing, agriculture, and non-timber forest resources face mounting threats from environmental changes.

The research examines the long-term impacts of climate change on both ecological and human systems in the ISD, focusing on how rising temperatures, increased tropical cyclones, storm surges, drought, altered rainfall patterns, and sea level rise are transforming the islands. Using satellite imagery spanning from 2000 to 2024, the study maps shift in island size and shape, as well as the condition of embankments, providing a spatial and temporal analysis of vulnerability across different locations. Two key indices—Normalized Difference Salinity Index (NDSI) and Normalized Difference Water Index (NDWI)—are employed to assess changes related to sea level rise, while geostatistical methods reveal long-term patterns and trends in these environmental impacts.

By documenting both physical alterations and the experiences of residents, the study highlights the escalating risks posed by climate change to coastal populations. It emphasizes the urgent need for targeted interventions and informs policymakers and stakeholders about effective adaptive strategies. The findings underscore the importance of resilience and community-led adaptation as essential responses to ongoing ecological and socio-economic challenges. In sum, this research provides a comprehensive understanding of how climate change is reshaping the ISD and offers guidance for sustainable management and policy development in similarly vulnerable coastal regions.