Coastal Erosion Vulnerabilities, Monsoon Dynamics, and Human Adaptive Response

This project will investigate how coastal erosion in low elevation environments is linked to seasonal precipitation patterns, how humans perceive their vulnerability to erosion risk, and how humans secure livelihoods in the face of erosion. Rural populations in coastal zones are dependent on land resources to support agriculture and on marine resources to support fishery-based activities. Coastal erosion has potential to threaten economic and geopolitical stabilities due to the permanent nature of lost land resources that deprives population of land-based resources and access to marine resources. Variation in the location and timing of erosion events produces uncertainty for populations who must negotiate erosion threats without the benefit of consistent science-informed information regarding risk and vulnerability. This project contributes to a better understanding of the intersection of coastal environmental change, lowland coastal populations, atmospheric science, and economic development. Results will inform coastal processes, as well as human vulnerability and resilience, and will also make methodological advances in quantitative geospatial analysis. Students will be trained in STEM science and project elements will be used to enhance modules of existing courses at two universities. Project results will be disseminated in journals and other outlets, presented to government agencies and NGOs, and shared with local stakeholders. The project will become registered with the Resilience Connections Network, an international virtual space for the interaction between global and local leaders on resilience science and practitioners.

The study site for this project is the delta of a large river that is the outlet for water discharge driven by monsoon precipitation in a large watershed with a shoreline particularly vulnerable to erosion. The region has high rates of annual erosion whereby shorelines may retreat over 100 meters per year causing livelihood disruption and displacement of farming and fishing households. The project has three objectives. The first objective characterizes time-space patterns of shoreline erosion and monsoon dynamics at multiple scales. Understanding erosion rates at annual scales is particularly important to characterize vulnerability because households need to forecast and respond over relatively short time horizons that are not resolved at coarser decadal scales. The second objective assesses predictive relationships between monsoon precipitation and erosion dynamics with the hypothesis that time-space patterns of rainfall can help predict erosion behavior. A third objective assesses social vulnerability, risk perception and how resource endowments and adaptive behavior may promote resilience. These objectives will be addressed using a mixed-methods approach that combines geospatial analysis using earth observation data, statistical and machine-learning predictive modelling, and quantitative and qualitative primary social data collected in two villages. Investigators will produce an approximately 50-year time series record of shoreline change that will used in concert with monthly precipitation data to develop an annual predictive model of erosion risk. Field research will be done to collect social data from local populations in terms of their risk perception, vulnerability, and adaption behaviors by conducting a household survey, focus groups, and key informant interviews. Although the project will focus on the delta region of the Ganges-Brahmaputra-Meghna river system in Bangladesh, the research will provide new insights for dealing with coastal erosion in densely populated coastal zones in other regions, including the United States.