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Hurricanes can trigger widespread landslides and flooding creating compound hazards and multiple risks for vulnerable populations. An example is the island of Dominica in the Caribbean, where the population lives predominantly along the coast close to sea level and is subject to storm surge, with steep topography rising behind, with a propensity for landslides and flash river flooding. The simultaneous occurrence of the multiple hazards amplifies their impacts and couples with physical and social vulnerabilities to threaten lives, livelihoods, and the environment. Neglecting compound hazards underestimates overall risk. Using a whole island macroscale, (level-I) analysis, susceptibility scenarios for hurricanes, triggered landslides, and floods were developed by incorporating physical process parameters. The susceptibilities were combined with vulnerability indicators to map spatial patterns of hurricane multi-risks in Dominica. The analysis adopted a coupled approach involving the frequency ratio (FR), analytic hierarchy process (AHP), and geographic information system (GIS). Detailed hazard modelling was done at selected sites (level-II), incorporating storm surge estimates, landslide runout simulations, and steady flow analysis for floods. High-resolution terrain data and simulation models, the Rapid Mass Movement Simulation (RAMMS) and the hydrologic engineering center's river analysis system (HEC-RAS), were employed. Ground validation confirmed reasonable agreement between projected and observed scenarios across different spatial scales. Following the United Nations Office for disaster risk reduction (UNDRR) call for the inclusion of local, traditional, and indigenous knowledge, feedback, and expert opinion to improve understanding of disaster risk, 17 interviews with local experts and 4 participatory workshops with residents were conducted, and findings were incorporated into the analysis, so as to gain insights into risk perceptions. The study's outcomes encompass projections and quantification of hurricane compound hazards, vulnerabilities, accumulated risks, and an understanding of local priorities. These findings will inform decision-making processes for risk mitigation choices and community actions by providing a new framework for multi-hazard risk assessment that is easy to implement in combining different data forms. [ABSTRACT FROM AUTHOR]

Climate variability and Land use practices significantly alter the hydrological processes at local and regional levels. The Upper Jhelum catchment is an important Himalayan catchment which is the head-water region of the river Jhelum. The focus of this study is to examine the impact of climate variability and land use land cover dynamics on the hydrological regime in the study area. This study used the physically based distributed hydrological model, Soil and Water Assessment Tool (SWAT) to assess the individual and combined contribution of climate variability and Land use/Land cover changes on the hydrological processes operating on multiple sub-watersheds of the region. The model was calibrated and validated for multi-site monthly stream flow. The R2, ENS and PBIAS values ranged from, 0.71–0.81, 0.56–0.88, and 0.74–0.94 respectively for calibration and 0.69–0.8, 0.51–0.87, and ‒2.3–10.2 respectively for validation. To study the separate and combined effects of climate variability and land-use, we set up the model for four scenarios of different combinations of land use maps and climate data. The results reveal the change in land use has led to increase in the evapotranspiration rates. While all other hydrological processes (Groundwater Flow, Surface Flow and Water yield) were more sensitive to climate variability and it has led to an overall decrease in the water resources of the region. A peculiar trend of the left bank watersheds being more sensitive to the landuse change in addition to climate variability was also strongly depicted in the results. [ABSTRACT FROM AUTHOR]

Considering the sensitivity and importance of water resources in the Himalayan uplands, this study intended to assess the hydrological responses to climate change in the Jhelum basin. Representative concentration pathway (RCP)–based projections from six dynamically downscaled global circulation models (GCMs) were bias-corrected for developing the climatic projections over the twenty-first century. The uncertainty associated with GCM outputs was addressed by using multi-model ensemble projections developed through Bayesian model averaging (BMA) technique. The assessment reveals that compared to the baseline (1980–2010) values, the annual mean maximum temperature in the basin will rise by 0.41–2.31 °C and 0.63–4.82 °C, and the mean minimum temperature will increase by 1.39–2.37 °C and 2.14–4.34 °C under RCP4.5 and RCP8.5, respectively. While precipitation is expected to decrease by 7.2–4.57% and 4.75–2.47% under RCP4.5 and RCP8.5, correspondingly. BMA ensemble projections were coupled with the Soil and Water Assessment Tool (SWAT) to simulate the future hydrological scenarios of the drainage basin. With the changing climate, the discharge of rivers in the Jhelum basin is expected to witness reductions by about 23–37% for RCP4.5 and 19–46% for RCP8.5. Moreover, the water yield of the basin may also exhibit decreases of 17–25% for RCP4.5 and 18–42% for RCP8.5. The projected scenarios are likely to cause water stress, affect the availability of water for diverse uses, and trigger transboundary water-sharing-related conflicts. The impact of climate change on discharge demands early attention for the formulation of mitigation and adaptive measures at the regional level and beyond. [ABSTRACT FROM AUTHOR]

The present study intends to assess the climatic controls on the streamflow and its impacts on the changing form of hydrological extremes in the Jhelum basin. The study entails robust statistical analysis of the observed hydroclimatic data (1980–2016) using the standard procedures of trend and abrupt change point detection, flood frequency analysis (FFA), and streamflow drought index (SDI). The coupled impact of rising temperatures (0.024 °C/year) and diminishing precipitation (− 5.71 mm/year) is yielding substantial decreases in the streamflow of the Jhelum basin. The other manifestations of changing climatic regimes are the increasing trends in the spring season (March-May) streamflow and the concurrence of abrupt change points in the streamflow data with climatic variables. The climate change signals are well evident over the hydrological extremes, reflected in an enhanced occurrence of droughts through the latter half of the examined period. Moreover, the flood frequency estimates show that the magnitude of the peak discharges about different return periods has increased significantly during 1986–2016 compared to 1956–1985 estimates. The magnitude of 100-year recurrence interval flood has increased by 10.54–79.58% during 1986–2016. The current study calls for the inclusive restructuring of water management practices to offset the impacts of changing hydrological extremes in the basin. [ABSTRACT FROM AUTHOR]

This research article provides added evidence in support of the already presented tectonic evolution model of the Kashmir basin by Alam et al. (2015), which states that the local dextral strike–slip structure, embedded with the southern forefront thrust system (MBT/MCT), resulted in the development of the NNW–SSE-oriented elliptical pull-apart sedimentary trough (Kashmir basin). Simultaneously, we respond to the argument of Shah (2015), wherein the author expresses his concern about the tectonic evolution model proposed by Alam et al. (2015). The commentator (Shah, 2015)—merely based on assumptions (1: perfectly planar geometry of the central Kashmir fault-CKF; 2: pure strike–slip along the CKF) and misinterpretations of the data (tectonic, geologic, structural, seismic, geodetic, and geomorphic)—makes extraneous criticism throughout the length of his commentary by referring copied text/figures. However, Alam et al. (2015) projected the CKF as noticeably curvilinear major exhibiting complex strike–slip tectonics (dextral, lateral, and vertical motion). Moreover, contradictory to the claim of Shah (2015), the tectonic, geologic, structural, seismic, geodetic, and geomorphic data is in complete agreement with the model proposed by Alam et al. (2015). Hence, in addition to complimentary evidence for the dextral strike–slip, pull-apart evolution of the Kashmir basin, a detailed response is provided to the commentary of Shah (2015). [ABSTRACT FROM AUTHOR]

The Balapur fault (BF) is a high angle thrust fault (reverse), dipping ~ 60° NE, with an established length of ~ 40 km striking NW–SE of the Kashmir basin. However, geomorphic traces suggest that the strike of the BF propagates beyond what has been documented previously. The present investigation aims to identify the unrecognized segment of the BF in the SW of the Kashmir basin using hypsometric variability in longitudinal profiles (knickpoints/zones), followed by validation through stream gradient index ( SL ) calculations of the rivers draining the area. The longitudinal profiles of all the streams indicate prominent and consistent anomalies in the upper and mid-reaches even on the coarse resolution data (Survey of India topographic maps — 1:50,000/40 m, DEM-SRTM 90 m). The profile anomalies in the upper reaches (hard rock zone) of the streams may be attributed to lithological contacts, i.e., Panjal trap agglomeratic slate–shale–limestone. However, the river profile convex segments and course deflection specifically in the mid-reaches (soft rock zone) are most likely associated with recent tectonic activity. Geomorphic signatures suggest that these anomalies coincide with the strike of the recognized segment of the BF. Moreover, the SL values of each stream express a clear agreement with the anomalies shown by the long profiles of the rivers. Hence, we infer that the strike of the BF extends for a significant distance (~ 95 km) over the northeastern flank of the Pir Panjal range in the NW–SE direction. [ABSTRACT FROM AUTHOR]

Morphometric parameters can be useful tools to provide general understanding of physical characteristics of drainage basin with respect to floods. To evaluate the flood influencing factors in the upper Jhelum basin, we delineate the upper Jhelum basin into ten sub-basins, followed by extraction of drainage network and morphometric parameters using Advanced Spaceborne Thermal Emission and Reflection Radiometer digital elevation model and topographic maps in Geographic Information System. The overall flood potential was determined on the basis of compound value obtained for all morphometric parameters of each sub-basin. The analysis reveals that, in general, the northeastern segment of the upper Jhelum basin reveals comparative higher flood potential than the southwestern segment. The tributaries, such as Lidder, Veshav, Arapal, Arapat, and Bring, exhibit greater potential to produce peak flows during rainfall events, while the tributaries like Dudhganga, Rambiara, Sandran, Romushi, and Sasara express moderate-to-low flood potential, respectively. The results of this study are likely to be very useful for effective flood hazard mitigation in upper Jhelum floodplain. [ABSTRACT FROM AUTHOR]

This study aims at assessing the tectonic and climatic responses to landscape changes transpired in the Durung Drung basin in the Zanskar Himalaya. We used relevant geomorphic indices interpreted from ASTER DEM satellite data and supplemented by the field observations to decipher active tectonics and resultant changes in the landscape. A N-S trending fault in the north of the basin was studied with the help of basin geometry which includes relative parameter, length area relation, form factor, shape factor ratio, elongation ratio, circulatory ratio, compactness coefficient and morphotectonic indices (e.g., drainage basin asymmetry, mountain front sinuosity, hypsometric integral, topographic symmetric factor) to comprehend the geomorphic signatures of the active tectonics. The geomorphic indices indicate upliftment and tilting of the basin. The data on mountain front index and hypsometric integral reveal the uplift and high relief. We propose that the western side of the basin is tectonically more active than eastern side, suggesting active upliftment. The convex nature of hypsometric curve and strongly elongated circulatory ratio reflect competing role of deformation by tectonics. The results of mountain front index and hypsometric integral reveal high relief and uplift. Overall deglaciation of 12.91% was observed in the basin. Analysis of the meteorological data for the last century (1901–2017) indicate that increase in minimum and maximum temperature coupled with increase in liquid precipitation are probably the main drivers of glacier depletion. We conclude that the drainage system of this basin is structurally controlled and overall landscape change is significantly influenced by the ongoing perturbations in the climate system. [ABSTRACT FROM AUTHOR]