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1. Monsoon Dynamics in the Ganges-Brahmaputra-Meghna Basin

   https://doi.org/10.3390/CHyCle-2017-04865  

   Curtis, Scott; Crawford, Thomas; Munshi, Khaled; Paul, Bimal (September 2017, The 1st Electronic Conference on Hydrological Cycle (CHyCle-2017))

   A recently funded US National Science Foundation project seeks to investigate monsoon variability within the Ganges-Brahmaputra-Meghna (GBM) river basin as a potential predictor for annual shoreline erosion rates in the lower coastal delta region. Many previous studies have examined the interannual variability of South Asian precipitation either within political boundaries or across large spans of latitudes and longitudes, but few have taken a more hydrologic approach by analyzing the atmospheric-oceanic forcings that lead to precipitation falling only within the GBM basin. The temporal climate patterns would likely be different from previous studies and are hypothesized to have a more direct effect on outlet discharge and erosion rates. In the present study, mean monsoon precipitation (June-July-August-September) for the 2,309 0.25° grid boxes of the Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks-Climate Data Record (PERSIANN-CDR) was extracted using geospatial methods. A Principal Component (PC) analysis was performed over the period 1983 to 2015. The first PC explains 88.7% of the variance and resembles climatology with the center of action over Bangladesh. The eigenvector shows a downward trend consistent with studies reporting a recent decline in monsoon rainfall. The second PC explains 2.9% of the variance and concentrates rainfall in the western portion of the basin. The 2nd component has greater temporal variability than the 1st component and an apparent decadal cycle. An analysis of global precipitation indicates that the rainfall patterns obtained within the GBM are localized. Surface and upper-air atmospheric height fields suggest the 2nd PC pattern is forced by a Rossby wave train stemming from the North Atlantic. 

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2. A Hydroclimatological Analysis of Precipitation in the Ganges–Brahmaputra–Meghna River Basin

   https://doi.org/10.3390/w10101359  

   Curtis, Scott; Crawford, Thomas; Rahman, Munshi; Paul, Bimal; Miah, M.; Islam, M.; Patel, Mohin (October 2018, Water)

   Understanding seasonal precipitation input into river basins is important for linking large-scale climate drivers with societal water resources and the occurrence of hydrologic hazards such as floods and riverbank erosion. Using satellite data at 0.25-degree resolution, spatial patterns of monsoon (June-July-August-September) precipitation variability between 1983 and 2015 within the Ganges–Brahmaputra–Meghna (GBM) river basin are analyzed with Principal Component (PC) analysis and the first three modes (PC1, PC2 and PC3) are related to global atmospheric-oceanic fields. PC1 explains 88.7% of the variance in monsoonal precipitation and resembles climatology with the center of action over Bangladesh. The eigenvector coefficients show a downward trend consistent with studies reporting a recent decline in monsoon rainfall, but little interannual variability. PC2 explains 2.9% of the variance and shows rainfall maxima to the far western and eastern portions of the basin. PC2 has an apparent decadal cycle and surface and upper-air atmospheric height fields suggest the pattern could be forced by tropical South Atlantic heating and a Rossby wave train stemming from the North Atlantic, consistent with previous studies. Finally, PC3 explains 1.5% of the variance and has high spatial variability. The distribution of precipitation is somewhat zonal, with highest values at the southern border and at the Himalayan ridge. There is strong interannual variability associated with PC3, related to the El Nino/Southern Oscillation (ENSO). Next, we perform a hydroclimatological downscaling, as precipitation attributed to the three PCs was averaged over the Pfafstetter level-04 sub-basins obtained from the World Wildlife Fund (Gland, Switzerland). While PC1 was the principal contributor of rainfall for all sub-basins, PC2 contributed the most to rainfall in the western Ganges sub-basin (4524) and PC3 contributed the most to the rainfall in the northern Brahmaputra (4529). Monsoon rainfall within these two sub-basins were the only ones to show a significant relationship (negative) with ENSO, whereas four of the eight sub-basins had a significant relationship (positive) with sea surface temperature (SST) anomalies in the tropical South Atlantic. This work demonstrates a geographic dependence on climate teleconnections in the GBM that deserves further study. 

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3. Coastal Erosion and Human Perceptions of Revetment Protection in the Lower Meghna Estuary of Bangladesh

   https://doi.org/10.3390/rs12183108  

   Crawford, Thomas W.; Islam, Md Sariful; Rahman, Munshi Khaledur; Paul, Bimal Kanti; Curtis, Scott; Miah, Md. Giashuddin; Islam, Md. Rafiqul (September 2020, Remote Sensing)

   null (Ed.)

   This study investigates coastal erosion, revetment as a shoreline protection strategy, and human perceptions of revetments in the Lower Meghna estuary of the Bangladesh where new revetments were recently constructed. Questions addressed were: (1) How do rates of shoreline change vary over the period 2011–2019? (2) Did new revetments effectively halt erosion and what were the magnitudes of erosion change? (3) How have erosion rates changed for shorelines within 1 km of revetments, and (4) How do households perceive revetments? High-resolution Planet Lab imagery was used to quantify shoreline change rates. Analysis of household survey data assessed human perceptions of the revetment’s desirability and efficacy. Results revealed high rates of erosion for 2011–2019 with declining erosion after 2013. New revetments effectively halted erosion for protected shorelines. Significant spatial trends for erosion rates existed for shorelines adjacent to revetments. Survey respondents overwhelmingly had positive attitudes about a desire for revetment protection; however, upstream respondents expressed a strong majority perception that revetment acts to make erosion worse. Highlights of the research include integration of remote sensing with social science methods, the timing of the social survey shortly after revetment construction, and results showing significant erosion change upstream and downstream of new revetments. 

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4. Livelihood dynamics and hazard perception in a deltaic landscape: a hydrosocial assessment of riverbank erosion in the lower Meghna River, Bangladesh

   https://doi.org/10.3389/frwa.2025.1634249  

   Popke, Jeff; Rahman, Mizanur (August 2025, Frontiers in Water)

   Mazzonlini, Maurizio (Ed.)

   Delta regions represent unique settings characterized by a combination of dynamic hydrological environments and livelihood opportunity. They are sites of intensive human activity and infrastructure development aimed at managing the environment and ameliorating hazards such as riverbank erosion. In this paper, we present a case study from the Meghna River delta highlighting livelihood dynamics in the context of riverbank erosion and the recent construction of a protective concrete revetment. To account for the hydrological, socioeconomic, and infrastructural dynamics of the delta environment, we characterize our setting as a hydrosocial territory, and we draw from interviews with local residents to document key dimensions of delta life within the Meghna estuary. Our findings show that the delta environment provides opportunity for local residents, but that riverbank erosion has led to significant displacement and is a source of anxiety for many. We also find that both the nature of the hazard and the limited extent of the new embankment have led to an uneven hydrosocial territory characterized by social and spatial inequality. Despite ongoing challenges, our study shows that riverside dwellers are active agents who manage to craft unique hybrid livelihoods from within the Meghna floodplains. 

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5. Diverse sedimentary organic matter within the river-aquifer interface drives arsenic mobility along the Meghna River Corridor in Bangladesh

   https://doi.org/10.1016/j.apgeochem.2023.105883  

   Varner, Thomas S.; Kulkarni, Harshad V.; Kwak, Kyungwon; Cardenas, M. Bayani; Knappett, Peter S.K.; Datta, Saugata (January 2024, Applied Geochemistry)