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Guru Prasath, J.; Sannasiraj, S.A., and Chandramohan, P., 2024. Nearshore morphological changes due to severe cyclonic storm activity along the east coast of India. Journal of Coastal Research, 40(4), 696–713. Charlotte (North Carolina), ISSN 0749-0208. Nearshore waves, wind, and tidal current mobilize seabed sediments; sort, transport, and redistribute the sediments; and modify the nearshore seabed morphology. Waves play a dominant role in morphological changes among winds, waves, and tidal currents. The nearshore wave breaking induces the initiation of sediment movement, and the associated alongshore current transports a large volume of sediments that tend to either accrete toward or erode from the beach face and seabed. Sediment transport rate in the nearshore waters during cyclones is higher than that under normal conditions. The measured changes due to Cyclone Nivar in November 2020 in the nearshore morphology along the Mahabalipuram coast are examined to understand the response of nearshore morphology to cyclonic wave-induced forcing. The beach-profile measurements across 10 transects at 100 m spacing covering about 1000 m along the coast were measured before and after the passage of Cyclone Nivar as a part of the present field study. The evolving beach profiles during Cyclone Nivar were simulated using the storm-induced beach change (SBEACH) model, which is a cross-shore profile evolution model. The changes due to berm erosion and deposition of nearshore sand bars have been compared from field measurements data and model prediction. The calibrated model was then used to simulate the beach profile response at two other locations along the cyclone-affected coastline to examine the shoreline impact. The calibrated model can be used along the coast to understand the poststorm profiles of the beach with reasonable accuracy. [ABSTRACT FROM AUTHOR]

Forecasting of sediment load (SL) is essential for reservoir operations, design of water resource structures, risk management, water resource planning and for preventing natural disasters in the river basin systems. Direct measurement of SL is difficult, labour intensive, and expensive. The development of an accurate and reliable model for forecasting the SL is required. Sediment transport is highly non-linear and is influenced by a variety of factors. Forecasting of the SL using various conventional methods is not highly accurate because of the association of various complex phenomena. In this study, major key factors such as rock type (RT), relief (R), rainfall (RF), water discharge (WD), temperature (T), catchment area (CA), and SL are recognized in developing the one-step-ahead SL forecasting model in the Mahanadi River (MR), which is among India's largest rivers. Artificial neural networks (ANN) in conjunction with multi-objective genetic algorithm (ANN-MOGA)-based forecasting models were developed for forecasting the SL in the MR. The ANN-MOGA model was employed to optimize the two competing objective functions (bias and error variance) with simultaneous optimization of all associated ANN parameters. The performances of the proposed novel model were finally compared to other existing methods to verify the forecasting capability of the model. The ANN-MOGA model improved the performance by 12.81% and 10.19% compared to traditional AR and MAR regression models, respectively. The results suggested that hybrid ANN-MOGA models outperform traditional autoregressive and multivariate autoregressive forecasting models. Overall, hybrid ANN-MOGA intelligent techniques are recommended for the forecasting of SL in rivers because of their relatively better performance as compared to other existing models and simplicity of application. [ABSTRACT FROM AUTHOR]

The morphometric analysis was carried out on the Halayapura microwatershed in Karnataka, India. Using ArcGIS 10.2.2 and applying the DEM model, the micro-watershed was subjected to quantitative investigation to determine the channel network involved and understand geo-hydrological behavior. In addition, remote sensing and geospatial techniques were used to study the micro-watershed drainage analysis and its associated parameters, such as stream order, stream length, stream frequency, drainage density, texture ratio, form factor, circulatory ratio, elongation ratio, bifurcation ratio, and compactness coefficient for the micro watershed, were evaluated. According to the findings, the stream order ranges from I to IV, with 97 streams in the micro-watershed. Streams of 72, 19, 5, and 1 are found in the I, II III, and IV order, respectively. The bifurcation values range from 3.78 to 5.00, with the average weight around 3.14. The elongation ratio and farm factor are 0.77 and 0.46, respectively. The drainage density of the micro watershed is 5.20 km/km². The form factor, circularity, and elongation ratio contribute to a basin with an elongated shape through decreased flood proneness, erosion, and sediment transport capacity. The results of the microwatershed morphometric assessment are critical for evaluating and managing water resources and selecting a recharge structure for future water management in the study region. [ABSTRACT FROM AUTHOR]

Black, K.P.; Baba, M.; Mathew, J.; Kurian, N.P., and Ilic, A., 2021. Guidelines to prepare India's coast for climate change. Journal of Coastal Research, 37(6), 1117–1129. Coconut Creek (Florida), ISSN 0749-0208. India's first coastal protection guidelines for climate-change adaptation are described. The guidelines are holistic, recognizing the links between engineering, economic, physical, legal, social, environmental, and governmental intricacies. Robust protection solutions under climate change for millions of coastal residents may occur only when all these facets are improved within the complex regulatory, budgetary, and practical circumstances in India. Fifty-seven specific guidelines are presented in nine categories ranging from administrative to best-practice coastal protection. An "environmental softness ladder" that ranks coastal protection methods was developed as a scientific tool to guide policy development and project implementation. "Minimum floor level" for safe building was defined for each Indian coastal state using climate-change data produced for the study by Indian and international institutes. Beaches are more stable when the net sediment transport fluxes are close to neutral. "Grand schemes," which make large-scale changes to the coast rather than continuing with piecemeal localised works, are recommended. With diverse dynamics over a long coastline in India, the 4-year study engaged an exceptionally large number of experts, agencies, government bodies, development partners, and other stakeholders. [ABSTRACT FROM AUTHOR]