Roads are the most critical means of connectivity in Himalayan villages.However,the terrain is inherently fragile with varied geological,geomorphological,ecological,and climate regimes,that result in frequent slope fa...Roads are the most critical means of connectivity in Himalayan villages.However,the terrain is inherently fragile with varied geological,geomorphological,ecological,and climate regimes,that result in frequent slope failure and disruption in connectivity.The risk is further to be increased by extreme events-generated hazards,which are expected to rise in frequency and magnitude with ongoing intervention,however,can improve the sustainability of road networks.The present study attempts to analyse and quantify the impacts of a major road widening project initiated in 2018 in the upper Ganga catchment,Uttarakhand Himalaya which has destabilised valley slopes along the widened segments.Also,a large quantity of excavated sediments is dumped down slopes,which is posing a threat to aquatic biodiversity.The estimates are based on Google Earth imagery of a few representative road segments recently widened in the upper Ganga catchment,which indicate a substantial increase in the landslide and unstable slope area following the road widening.The increase in unstable slope area is attributed to improper road widening approaches and poor slope management in seismically active Himalayan terrain.Further,the mean velocity plots of Persistent Scatterer Interferometric Synthetic Aperture Radar(PSInSAR)indicate that the segments undergoing road widening are coherent with areas of significant earth surface change.A broad correlation between the road width and sediment yield indicates that even a slight increase in road width can result in a large-scale mass removal from the toe of the hillslope,inflicting cascading impact on hillslopes.The study recommends a more flexible road construction approach based on the environmental and geological aspects of the terrain for sustainable road networks.Further,the impact of climate change is looming over the Himalayas,and the relation between climate change and its potential effects on the stability of slopes remains an open issue.展开更多
This paper proposes the mathematical model to investigate how to compute and analyze the tsunami wave parameters and the retrieval of its early warning using remote sensing technique to improve the detection rate.The ...This paper proposes the mathematical model to investigate how to compute and analyze the tsunami wave parameters and the retrieval of its early warning using remote sensing technique to improve the detection rate.The different methods available for the evaluation of the tsunami detection systems are also introduced.This research work is to compute and analyze the tsunami wave parameters such as Eigen functions in deep,intermediate and shallow water regions.The computational and algorithmic analysis of tsunami wave parameters are achieved in three steps:the first step is to calculate the earthquake fault parameters such as length,width,area and displacement from the epicenter,which corresponds to the effect of its variation with respect to the earthquake magnitude.The variation of each fault parameters have been measured and recorded out over the certain moment of magnitudes(M).This shows smaller values as compared to the earthquake magnitude M 9.5 at which all the parameters shows very large response.The second step involves the measurements of water wave angular frequency in deep,intermediate and shallower region of ocean.The values of angular frequencies in deep water shows the lesser response as compared to other two water conditions because,in deep water the angular velocity of water particles travels with the lesser speed as compared to the shallower region as per Airy’s wave theory.The simulation results show the angular velocity in Deep Ocean is very less,moderate in the intermediate water and very high on the coastal region.It indicates the higher impact on coastal region.The third step involves the simulation study of measurement of tsunami Eigen functions such as orbital velocity,acceleration,wave potential in deep,intermediate and shallower water regions.The simulation result shows the resultant orbital velocity and accelerations in deep,intermediate and shallow water regions provides the similar response as angular velocity due to same proportion of the water displacement from deep to coastal regions.Hence the dynamic forces are very high approximately 1 km from the beaches.Once the Tsunami waves approaches to the beach,wave height increases whereas particle acceleration decreases because near the coast,due to geological structure of the earth’s surface,inertia and gravity forces increase to the extreme limits,while particle acceleration and velocity values reach close to zero.The wave potential Eigen function has also been plotted and measured with respect to the water depth condition and the similar response is obtained in the simulation result.The validation of each result has also been presented with the standard simulated data,which shows the results as less than 10%of the accuracy.展开更多
Tsunami early warning systems have provided to be the extreme importance after the tsunami that hit Japan in March 2011.This research article presents a case study based on the tsunami detection using Bottom Pressure ...Tsunami early warning systems have provided to be the extreme importance after the tsunami that hit Japan in March 2011.This research article presents a case study based on the tsunami detection using Bottom Pressure Rate(BPR)measurement and the post the analysis using the SAR datasets.A final decision based system using BPR has been studied to carry out the measurements of tsunami wave parameters.SAR based study has also been carried out for the post tsunami studies.Wiener filters are utilized to remove the speckle noise presents in imagery.Future scope of this work has also been proposed.展开更多
基金the Department of Science&Technology,Govt.of India vide Inspire Faculty Project:DST/INSPIRE/04/2017/001289 for financial support for the studythe Ministry of Earth Science for Financial Support vide Research Project:MoES/P.O.(Geo)/95/2017。
文摘Roads are the most critical means of connectivity in Himalayan villages.However,the terrain is inherently fragile with varied geological,geomorphological,ecological,and climate regimes,that result in frequent slope failure and disruption in connectivity.The risk is further to be increased by extreme events-generated hazards,which are expected to rise in frequency and magnitude with ongoing intervention,however,can improve the sustainability of road networks.The present study attempts to analyse and quantify the impacts of a major road widening project initiated in 2018 in the upper Ganga catchment,Uttarakhand Himalaya which has destabilised valley slopes along the widened segments.Also,a large quantity of excavated sediments is dumped down slopes,which is posing a threat to aquatic biodiversity.The estimates are based on Google Earth imagery of a few representative road segments recently widened in the upper Ganga catchment,which indicate a substantial increase in the landslide and unstable slope area following the road widening.The increase in unstable slope area is attributed to improper road widening approaches and poor slope management in seismically active Himalayan terrain.Further,the mean velocity plots of Persistent Scatterer Interferometric Synthetic Aperture Radar(PSInSAR)indicate that the segments undergoing road widening are coherent with areas of significant earth surface change.A broad correlation between the road width and sediment yield indicates that even a slight increase in road width can result in a large-scale mass removal from the toe of the hillslope,inflicting cascading impact on hillslopes.The study recommends a more flexible road construction approach based on the environmental and geological aspects of the terrain for sustainable road networks.Further,the impact of climate change is looming over the Himalayas,and the relation between climate change and its potential effects on the stability of slopes remains an open issue.
文摘This paper proposes the mathematical model to investigate how to compute and analyze the tsunami wave parameters and the retrieval of its early warning using remote sensing technique to improve the detection rate.The different methods available for the evaluation of the tsunami detection systems are also introduced.This research work is to compute and analyze the tsunami wave parameters such as Eigen functions in deep,intermediate and shallow water regions.The computational and algorithmic analysis of tsunami wave parameters are achieved in three steps:the first step is to calculate the earthquake fault parameters such as length,width,area and displacement from the epicenter,which corresponds to the effect of its variation with respect to the earthquake magnitude.The variation of each fault parameters have been measured and recorded out over the certain moment of magnitudes(M).This shows smaller values as compared to the earthquake magnitude M 9.5 at which all the parameters shows very large response.The second step involves the measurements of water wave angular frequency in deep,intermediate and shallower region of ocean.The values of angular frequencies in deep water shows the lesser response as compared to other two water conditions because,in deep water the angular velocity of water particles travels with the lesser speed as compared to the shallower region as per Airy’s wave theory.The simulation results show the angular velocity in Deep Ocean is very less,moderate in the intermediate water and very high on the coastal region.It indicates the higher impact on coastal region.The third step involves the simulation study of measurement of tsunami Eigen functions such as orbital velocity,acceleration,wave potential in deep,intermediate and shallower water regions.The simulation result shows the resultant orbital velocity and accelerations in deep,intermediate and shallow water regions provides the similar response as angular velocity due to same proportion of the water displacement from deep to coastal regions.Hence the dynamic forces are very high approximately 1 km from the beaches.Once the Tsunami waves approaches to the beach,wave height increases whereas particle acceleration decreases because near the coast,due to geological structure of the earth’s surface,inertia and gravity forces increase to the extreme limits,while particle acceleration and velocity values reach close to zero.The wave potential Eigen function has also been plotted and measured with respect to the water depth condition and the similar response is obtained in the simulation result.The validation of each result has also been presented with the standard simulated data,which shows the results as less than 10%of the accuracy.
文摘Tsunami early warning systems have provided to be the extreme importance after the tsunami that hit Japan in March 2011.This research article presents a case study based on the tsunami detection using Bottom Pressure Rate(BPR)measurement and the post the analysis using the SAR datasets.A final decision based system using BPR has been studied to carry out the measurements of tsunami wave parameters.SAR based study has also been carried out for the post tsunami studies.Wiener filters are utilized to remove the speckle noise presents in imagery.Future scope of this work has also been proposed.