Arpit Chouksey | IIT Guwahati (original) (raw)
Book by Arpit Chouksey
HYDRAULICS, WATER RESOURCES, COASTAL AND ENVIRONMENTAL ENGINEERING, Dec 18, 2014
The need for assessment of water resources availability in large and ungauged river basin is freq... more The need for assessment of water resources availability in large and ungauged river basin is frequent topic of discussion. It is now becoming increasingly important for water resources evaluation in India. Water resources development activities have focused attention on development and application of physically based hydrological models, which was used to simulate the impact of land and water use on water resources. The main objective of this study was to test the performance and feasibility of the SWAT (Soil and Water Assessment Tool) model for water balance study and prediction of stream flowin the Upper and Middle Narmada River Basin of India, which can be used for understanding the effects of future development and management actions. To simulate these impacts, long-term daily meteorological data was used.The Sequential Uncertainty domain parameter Fitting algorithm (SUFI-2) of SWAT CUP (Calibration and Uncertainty Program) with multiple sets of parametervalues is used for calibration and validation, over the entire basin.This calibration and validation was done based on the observed daily discharge data from India-WRIS (India – Water Resources Information System).The goal was to bracket most of the estimated data within the 95% prediction uncertainty (95PPU), by getting a significant coefficient of determination (R2) and coefficient of efficiency (NS) between observed and estimated data. The results after post calibration and validation indicates decrease in average annual water yield from 44.83 mm to 36.67 mm and R2 calculated before calibration 0.86 and increases to 0.88 after calibration. The simulation results indicate that relatively small parts of the total basin area have a high impact on the water balance in the catchment. It also indicates considerable reduction in surface runoff from 346.42 mm to 320.91 mm during 1979 to 1987.The results of present work also indicates that the parameter uncertainty is not the sole source of uncertainty; the model structure uncertainty is also important. These processes are mainly associated with the existing large reservoirs regulating the runoff of the River Narmada.
Conference by Arpit Chouksey
The need for assessment of water resources availability in large river basin is frequent topic of... more The need for assessment of water resources availability in large river basin is frequent topic of discussion. It is now becoming increasingly important for water resources evaluation in India. Water resources development activities have focused attention on development and application of physically based hydrological models, which was used to simulate the impact of land and water use on water resources. The main objective of this study was to do water balance study and prediction of stream flow in the Upper and Middle Narmada River Basin of India, which can be used for understanding the effects of future development and management actions. To simulate these impacts, long-term daily meteorological data was used. The results after post calibration and validation indicates decrease in average annual water yield from 44.83 mm to 36.67 mm. The simulation results indicate that relatively small parts of the total basin area have a high impact on the water balance in the catchment. It also indicates considerable reduction in surface runoff from 346.42 mm to 320.91 mm during 1979 to 1987. The results of present work also indicate that the parameter uncertainty is not the sole source of uncertainty; the model structure uncertainty is also important. These processes are mainly associated with the existing large reservoirs regulating the runoff of the River Narmada.
Papers by Arpit Chouksey
Lecture notes in civil engineering, 2023
Water and Energy International, 2008
Advances in Space Research
The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, 2020
The Himalayan region are home to the world's youngest and largest mountains, and origins of major... more The Himalayan region are home to the world's youngest and largest mountains, and origins of major rivers systems of South Asia. The present work highlight the importance of remote sensing (RS) data based precipitation and terrain products such as digital elevation models, glacier lakes, drainage morphology along with limited ground data for improving the accuracy of hydrological and hydrodynamic (HD) models in various Himalayan river basins such as Upper Ganga, Beas, Sutlej, Teesta, Koshi etc. The satellite based rainfall have mostly shown under prediction in the study area and few places have are also showing over estimation of rainfall. Hydrological modeling results were most accurate for Beas basin, followed by Upper Ganga basin and were least matching for Sutlej basin. Limited ground truth using GNSS measurements showed that digital elevation model (DEM) for carto version 3.1 is most accurate, followed by ALOS-PALSAR 12.5 DEM as compared to other open source DEMs. Major erosion and deposition was found in Rivers Bhagirathi, Alakhnanda, Gori Ganga and Yamuna in Uttarakhand state and Beas and Sutlej Rivers in Himachal Pradesh using pre and post flood DEM datasets. The terrain data and river cross section data showed that river cross sections and water carrying capacity before and after 2013 floods have changed drastically in many river stretches of upper Ganga and parts of Sutlej river basins. The spatio-temporal variation and evolution of glacier lakes was for lakes along with GLOF modeling few lakes of Upper Chenab, Upper Ganga, Upper Teesta and Koshi river basin was done using time series of RS data from Landsat, Sentinel-1 and Google earth images.
Water and Energy International, 2008
The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, 2018
The seasonal snow cover and permanent ice in form of Himalayan glaciers provide fresh water to ma... more The seasonal snow cover and permanent ice in form of Himalayan glaciers provide fresh water to many perineal rivers of Himalayas. The melt water from seasonal snow and glaciers, especially during of 15 March to 15 June acts as important source of water for drinking, hydropower and irrigation requirements of many areas in North India. This work has highlights the use of C-band Synthetic Aperture Radar (SAR) data from RISAT-1, Sentinel-1A and 1B satellites and ALOS-PALSAR-2 PolInSAR data for snow cover and glacier dynamics study for parts of North West Himalaya. Glacier velocity was derived using InSAR based method using 6 day temporal interval images from Sentinel-1 satellites and 14 day interval for PALSAR-2 satellite. High coherence was obtained for main glacier in both the data sets, which resulted accurate line of site (LOS) glacier velocity estimates for test glaciers. These InSAR data glacier velocity results are obtained after a gap of 21 years. Glacier facies was estimated using multi-temporal SAR image composition based classification. All these maps were verified by extensive ground surveys done at these sites during 2014-2017. The time series data of C-band SAR in VV/VH polarisation was also used to map snow cover in test basins of Bhagirathi and Beas River. The VV/VH data clearly shows difference between dry and wet snow, thus helping in improved snow cover mapping using SAR data. This study will help in refining algorithms to be used for such studies using upcoming NASA-ISRO SAR (NISAR) mission.
AGU Fall Meeting Abstracts, Dec 1, 2020
Geospatial Technologies for Land and Water Resources Management, 2021
Arabian Journal of Geosciences
International Journal of Advanced Remote Sensing and GIS, 2017
This study introduces about the parameterization of hydrological modelling for Asan and Song rive... more This study introduces about the parameterization of hydrological modelling for Asan and Song river basin the whole Doon Valley. SWAT an empirical hydrological model, VIC a physical hydrological model and HEC-HMS a semi distributed hydrological model are used for flood peak generation at predetermined locations. The land cover mapping of Doon Valley was attempted using remotely sensed images of Landsat and Google Earth imagery. The specific objectives are hydrological modelling for peak flow hydrograph generation, to observe LULC change scenarios between 1995, 2005 and 2014 year, comparison and validation of the simulated runoff using three different hydrological models (VIC, SWAT and HEC-HMS). The VIC model performance was found good and a close agreement between the observed and simulated values was obtained for 2014 LULC map. Model performance was also found good for other subbasins. The various input parameters are the meteorological data, discharge and sediment data were processed as per requirement of the SWAT model. The model was calibrated for the year 2006 to 2010. The Hydrological modeling indicates that the curve number is most influence parameter into the total discharge. Land use and vegetative cover play an important role in watershed runoff and stream flow discharge patterns over time, including peak flows. Increased human interventions have caused rapid transitions in land cover, adversely affecting the watershed processes and hydrological cycle in the long run. It may be concluded that the impact of land cover changes are most pronounced during low flows and that during high flows, role of land cover becomes comparatively less.
ABSTRACT The need for assessment of water resources availability in large and ungauged river basi... more ABSTRACT The need for assessment of water resources availability in large and ungauged river basin is frequent topic of discussion. It is now becoming increasingly important for water resources evaluation in India. Water resources development activities have focused attention on development and application of physically based hydrological models, which was used to simulate the impact of land and water use on water resources. The main objective of this study was to test the performance and feasibility of the SWAT (Soil and Water Assessment Tool) model for water balance study and prediction of stream flow in the Upper and Middle Narmada River Basin of India, which can be used for understanding the effects of future development and management actions. To simulate these impacts, long-term daily meteorological data was used. The Sequential Uncertainty domain parameter Fitting algorithm (SUFI-2) of SWAT CUP (Calibration and Uncertainty Program) with multiple sets of parameter values is used for calibration and validation, over the entire basin. This calibration and validation was done based on the observed daily discharge data from India-WRIS (India – Water Resources Information System).The goal was to bracket most of the estimated data within the 95% prediction uncertainty (95PPU), by getting a significant coefficient of determination (R2) and coefficient of efficiency (NS) between observed and estimated data. The results after post calibration and validation indicates decrease in average annual water yield from 44.83 mm to 36.67 mm and R2 calculated before calibration 0.86 and increases to 0.88 after calibration. The simulation results indicate that relatively small parts of the total basin area have a high impact on the water balance in the catchment. It also indicates considerable reduction in surface runoff from 346.42 mm to 320.91 mm during 1979 to 1987.The results of present work also indicates that the parameter uncertainty is not the sole source of uncertainty; the model structure uncertainty is also important. These processes are mainly associated with the existing large reservoirs regulating the runoff of the River Narmada.
Geospatial Technologies for Land and Water Resources Management, 2021
Water and Energy International, 2008
Springer Series in Geomechanics and Geoengineering, 2018
A watershed is an area of land from which all rain water drains to a common location. In their na... more A watershed is an area of land from which all rain water drains to a common location. In their natural state, streams and their associated floodplains provide a variety of important functions including the movement of water and sediment, storage of flood waters, recharge of groundwater, treatment of pollutants, dynamic stability, and habitat diversity. Disturbances to this system, either natural or human-induced, places stress on the system and has the potential to alter structure and/or impair the ability of the stream to perform ecological functions. Water conservation structures are helpful in maintaining the desired flow requirement and sediment yield within the watershed area. In this study, Jonk River, a tributary of Mahanadi basin has been selected to assess the impact of conservation structures for disaster risk reduction, sustainable agriculture and rural development. The outlet of Jonk River is located near Rampur in Chhattisgarh. Total area of the watershed is computed as 3424 km2. Soil and Water Assessment Tool (SWAT) has been used to calculate the discharge and sediment flow on daily and monthly basis for the year of 2001 considering two case scenarios i.e. with and without ponds as conservation structure (20 ponds in the villages are considered along the buffer area of the centreline of jonk river). The simulated discharge and sediment flow data has been compared with the observed data and the correlation coefficient is found to be 0.84 & 0.77 respectively. The annual discharge and sediment flow value in “with pond scenario” has been detected to be reduced by 69.27 and 64.10% respectively. The results observed in the present work can be used for site suitability analysis of soil and water conservation structures in the areas those are prone to soil erosion and floods. The study also reveals that the applications of Geographic Information Systems (GIS) and Geospatial Data Management can be used efficiently for watershed management and rural development.
Remote Sensing of Northwest Himalayan Ecosystems, 2018
Northwest Himalaya (NWH) has unique topographical and climate settings which makes this area pron... more Northwest Himalaya (NWH) has unique topographical and climate settings which makes this area prone to various types of hydrometeorological hazards such as flash floods, hail storms, glacier lake outburst floods, avalanches and mudflows. These hazards have high probability of turning into natural disasters if proper planning of natural resources, infrastructure and man-made structures is not done. Floods of June 2013 in Uttarakhand (Dobhal et al. 2013; Thakur et al. 2014) and 2014 floods of Srinagar (Bhatt et al. 2016) are prime examples of such hazards turning into the major disasters. Northwest Himalayan states in the last few years have experienced large number of hydrometeorological disasters such as high-intensity precipitation, cloud burst and subsequent flash flooding in downstream areas, snow avalanches, glacier lake outburst floods (GLOF), hail storms, drought and rainfall-induced mudflows (Kumar et al. 2015; Gupta et al. 2013; Kumar et al. 2012; Rana et al. 2012). This chap...
HYDRAULICS, WATER RESOURCES, COASTAL AND ENVIRONMENTAL ENGINEERING, Dec 18, 2014
The need for assessment of water resources availability in large and ungauged river basin is freq... more The need for assessment of water resources availability in large and ungauged river basin is frequent topic of discussion. It is now becoming increasingly important for water resources evaluation in India. Water resources development activities have focused attention on development and application of physically based hydrological models, which was used to simulate the impact of land and water use on water resources. The main objective of this study was to test the performance and feasibility of the SWAT (Soil and Water Assessment Tool) model for water balance study and prediction of stream flowin the Upper and Middle Narmada River Basin of India, which can be used for understanding the effects of future development and management actions. To simulate these impacts, long-term daily meteorological data was used.The Sequential Uncertainty domain parameter Fitting algorithm (SUFI-2) of SWAT CUP (Calibration and Uncertainty Program) with multiple sets of parametervalues is used for calibration and validation, over the entire basin.This calibration and validation was done based on the observed daily discharge data from India-WRIS (India – Water Resources Information System).The goal was to bracket most of the estimated data within the 95% prediction uncertainty (95PPU), by getting a significant coefficient of determination (R2) and coefficient of efficiency (NS) between observed and estimated data. The results after post calibration and validation indicates decrease in average annual water yield from 44.83 mm to 36.67 mm and R2 calculated before calibration 0.86 and increases to 0.88 after calibration. The simulation results indicate that relatively small parts of the total basin area have a high impact on the water balance in the catchment. It also indicates considerable reduction in surface runoff from 346.42 mm to 320.91 mm during 1979 to 1987.The results of present work also indicates that the parameter uncertainty is not the sole source of uncertainty; the model structure uncertainty is also important. These processes are mainly associated with the existing large reservoirs regulating the runoff of the River Narmada.
The need for assessment of water resources availability in large river basin is frequent topic of... more The need for assessment of water resources availability in large river basin is frequent topic of discussion. It is now becoming increasingly important for water resources evaluation in India. Water resources development activities have focused attention on development and application of physically based hydrological models, which was used to simulate the impact of land and water use on water resources. The main objective of this study was to do water balance study and prediction of stream flow in the Upper and Middle Narmada River Basin of India, which can be used for understanding the effects of future development and management actions. To simulate these impacts, long-term daily meteorological data was used. The results after post calibration and validation indicates decrease in average annual water yield from 44.83 mm to 36.67 mm. The simulation results indicate that relatively small parts of the total basin area have a high impact on the water balance in the catchment. It also indicates considerable reduction in surface runoff from 346.42 mm to 320.91 mm during 1979 to 1987. The results of present work also indicate that the parameter uncertainty is not the sole source of uncertainty; the model structure uncertainty is also important. These processes are mainly associated with the existing large reservoirs regulating the runoff of the River Narmada.
Lecture notes in civil engineering, 2023
Water and Energy International, 2008
Advances in Space Research
The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, 2020
The Himalayan region are home to the world's youngest and largest mountains, and origins of major... more The Himalayan region are home to the world's youngest and largest mountains, and origins of major rivers systems of South Asia. The present work highlight the importance of remote sensing (RS) data based precipitation and terrain products such as digital elevation models, glacier lakes, drainage morphology along with limited ground data for improving the accuracy of hydrological and hydrodynamic (HD) models in various Himalayan river basins such as Upper Ganga, Beas, Sutlej, Teesta, Koshi etc. The satellite based rainfall have mostly shown under prediction in the study area and few places have are also showing over estimation of rainfall. Hydrological modeling results were most accurate for Beas basin, followed by Upper Ganga basin and were least matching for Sutlej basin. Limited ground truth using GNSS measurements showed that digital elevation model (DEM) for carto version 3.1 is most accurate, followed by ALOS-PALSAR 12.5 DEM as compared to other open source DEMs. Major erosion and deposition was found in Rivers Bhagirathi, Alakhnanda, Gori Ganga and Yamuna in Uttarakhand state and Beas and Sutlej Rivers in Himachal Pradesh using pre and post flood DEM datasets. The terrain data and river cross section data showed that river cross sections and water carrying capacity before and after 2013 floods have changed drastically in many river stretches of upper Ganga and parts of Sutlej river basins. The spatio-temporal variation and evolution of glacier lakes was for lakes along with GLOF modeling few lakes of Upper Chenab, Upper Ganga, Upper Teesta and Koshi river basin was done using time series of RS data from Landsat, Sentinel-1 and Google earth images.
Water and Energy International, 2008
The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, 2018
The seasonal snow cover and permanent ice in form of Himalayan glaciers provide fresh water to ma... more The seasonal snow cover and permanent ice in form of Himalayan glaciers provide fresh water to many perineal rivers of Himalayas. The melt water from seasonal snow and glaciers, especially during of 15 March to 15 June acts as important source of water for drinking, hydropower and irrigation requirements of many areas in North India. This work has highlights the use of C-band Synthetic Aperture Radar (SAR) data from RISAT-1, Sentinel-1A and 1B satellites and ALOS-PALSAR-2 PolInSAR data for snow cover and glacier dynamics study for parts of North West Himalaya. Glacier velocity was derived using InSAR based method using 6 day temporal interval images from Sentinel-1 satellites and 14 day interval for PALSAR-2 satellite. High coherence was obtained for main glacier in both the data sets, which resulted accurate line of site (LOS) glacier velocity estimates for test glaciers. These InSAR data glacier velocity results are obtained after a gap of 21 years. Glacier facies was estimated using multi-temporal SAR image composition based classification. All these maps were verified by extensive ground surveys done at these sites during 2014-2017. The time series data of C-band SAR in VV/VH polarisation was also used to map snow cover in test basins of Bhagirathi and Beas River. The VV/VH data clearly shows difference between dry and wet snow, thus helping in improved snow cover mapping using SAR data. This study will help in refining algorithms to be used for such studies using upcoming NASA-ISRO SAR (NISAR) mission.
AGU Fall Meeting Abstracts, Dec 1, 2020
Geospatial Technologies for Land and Water Resources Management, 2021
Arabian Journal of Geosciences
International Journal of Advanced Remote Sensing and GIS, 2017
This study introduces about the parameterization of hydrological modelling for Asan and Song rive... more This study introduces about the parameterization of hydrological modelling for Asan and Song river basin the whole Doon Valley. SWAT an empirical hydrological model, VIC a physical hydrological model and HEC-HMS a semi distributed hydrological model are used for flood peak generation at predetermined locations. The land cover mapping of Doon Valley was attempted using remotely sensed images of Landsat and Google Earth imagery. The specific objectives are hydrological modelling for peak flow hydrograph generation, to observe LULC change scenarios between 1995, 2005 and 2014 year, comparison and validation of the simulated runoff using three different hydrological models (VIC, SWAT and HEC-HMS). The VIC model performance was found good and a close agreement between the observed and simulated values was obtained for 2014 LULC map. Model performance was also found good for other subbasins. The various input parameters are the meteorological data, discharge and sediment data were processed as per requirement of the SWAT model. The model was calibrated for the year 2006 to 2010. The Hydrological modeling indicates that the curve number is most influence parameter into the total discharge. Land use and vegetative cover play an important role in watershed runoff and stream flow discharge patterns over time, including peak flows. Increased human interventions have caused rapid transitions in land cover, adversely affecting the watershed processes and hydrological cycle in the long run. It may be concluded that the impact of land cover changes are most pronounced during low flows and that during high flows, role of land cover becomes comparatively less.
ABSTRACT The need for assessment of water resources availability in large and ungauged river basi... more ABSTRACT The need for assessment of water resources availability in large and ungauged river basin is frequent topic of discussion. It is now becoming increasingly important for water resources evaluation in India. Water resources development activities have focused attention on development and application of physically based hydrological models, which was used to simulate the impact of land and water use on water resources. The main objective of this study was to test the performance and feasibility of the SWAT (Soil and Water Assessment Tool) model for water balance study and prediction of stream flow in the Upper and Middle Narmada River Basin of India, which can be used for understanding the effects of future development and management actions. To simulate these impacts, long-term daily meteorological data was used. The Sequential Uncertainty domain parameter Fitting algorithm (SUFI-2) of SWAT CUP (Calibration and Uncertainty Program) with multiple sets of parameter values is used for calibration and validation, over the entire basin. This calibration and validation was done based on the observed daily discharge data from India-WRIS (India – Water Resources Information System).The goal was to bracket most of the estimated data within the 95% prediction uncertainty (95PPU), by getting a significant coefficient of determination (R2) and coefficient of efficiency (NS) between observed and estimated data. The results after post calibration and validation indicates decrease in average annual water yield from 44.83 mm to 36.67 mm and R2 calculated before calibration 0.86 and increases to 0.88 after calibration. The simulation results indicate that relatively small parts of the total basin area have a high impact on the water balance in the catchment. It also indicates considerable reduction in surface runoff from 346.42 mm to 320.91 mm during 1979 to 1987.The results of present work also indicates that the parameter uncertainty is not the sole source of uncertainty; the model structure uncertainty is also important. These processes are mainly associated with the existing large reservoirs regulating the runoff of the River Narmada.
Geospatial Technologies for Land and Water Resources Management, 2021
Water and Energy International, 2008
Springer Series in Geomechanics and Geoengineering, 2018
A watershed is an area of land from which all rain water drains to a common location. In their na... more A watershed is an area of land from which all rain water drains to a common location. In their natural state, streams and their associated floodplains provide a variety of important functions including the movement of water and sediment, storage of flood waters, recharge of groundwater, treatment of pollutants, dynamic stability, and habitat diversity. Disturbances to this system, either natural or human-induced, places stress on the system and has the potential to alter structure and/or impair the ability of the stream to perform ecological functions. Water conservation structures are helpful in maintaining the desired flow requirement and sediment yield within the watershed area. In this study, Jonk River, a tributary of Mahanadi basin has been selected to assess the impact of conservation structures for disaster risk reduction, sustainable agriculture and rural development. The outlet of Jonk River is located near Rampur in Chhattisgarh. Total area of the watershed is computed as 3424 km2. Soil and Water Assessment Tool (SWAT) has been used to calculate the discharge and sediment flow on daily and monthly basis for the year of 2001 considering two case scenarios i.e. with and without ponds as conservation structure (20 ponds in the villages are considered along the buffer area of the centreline of jonk river). The simulated discharge and sediment flow data has been compared with the observed data and the correlation coefficient is found to be 0.84 & 0.77 respectively. The annual discharge and sediment flow value in “with pond scenario” has been detected to be reduced by 69.27 and 64.10% respectively. The results observed in the present work can be used for site suitability analysis of soil and water conservation structures in the areas those are prone to soil erosion and floods. The study also reveals that the applications of Geographic Information Systems (GIS) and Geospatial Data Management can be used efficiently for watershed management and rural development.
Remote Sensing of Northwest Himalayan Ecosystems, 2018
Northwest Himalaya (NWH) has unique topographical and climate settings which makes this area pron... more Northwest Himalaya (NWH) has unique topographical and climate settings which makes this area prone to various types of hydrometeorological hazards such as flash floods, hail storms, glacier lake outburst floods, avalanches and mudflows. These hazards have high probability of turning into natural disasters if proper planning of natural resources, infrastructure and man-made structures is not done. Floods of June 2013 in Uttarakhand (Dobhal et al. 2013; Thakur et al. 2014) and 2014 floods of Srinagar (Bhatt et al. 2016) are prime examples of such hazards turning into the major disasters. Northwest Himalayan states in the last few years have experienced large number of hydrometeorological disasters such as high-intensity precipitation, cloud burst and subsequent flash flooding in downstream areas, snow avalanches, glacier lake outburst floods (GLOF), hail storms, drought and rainfall-induced mudflows (Kumar et al. 2015; Gupta et al. 2013; Kumar et al. 2012; Rana et al. 2012). This chap...
Drought is a condition of prolonged low rainfall leading to acute water shortage which has a huge... more Drought is a condition of prolonged low rainfall leading to acute water shortage which has a huge social and economic impact. Drought is classified as meteorological, hydrological, agriculture and socio-economic drought. As per the Ministry of Agriculture and Farmer’s Welfare, Government of India, 266 districts across 11 states in India were declared drought prone in 2016. Chhatarpur is a drought affected district of Bhundelkhand region, India. Around 60% of agricultural land of the district was transformed to fallow land, which has reduced the agricultural productivity by approximately 35% due to the effect of drought during year 2015-16. Therefore, assessment and monitoring of agriculture drought is very essential activity for supporting management and mitigation planning in the district. In the present study, Standard Precipitation Index (SPI) was used to identify and characterize the meteorological droughts. Impact of each meteorological drought on agriculture system was assesse...
Ice sheet features, glacier velocity estimation and glacier zones or facies classification are im... more Ice sheet features, glacier velocity estimation and glacier zones or facies classification are important research activities highlighting the dynamics of ice sheets and glaciers in Polar Regions and in inland glaciers. The Cband inSAR data is of ERS 1/2 tandem pairs with one day interval for spring of 1996 and L-band PolinSAR data of ALOS-PALSAR-2 for spring of 2015 is used in glacier velocity estimation. Glacier classification is done using multi-temporal C-and L-band SAR data and also with single date full polarization and hybrid polarization data. In first part, a mean displacement of 9 cm day-1 was recorded using SAR interferometric technique using ERS 1/2 tandem data of 25-26 March 1996. Previous studies using optical data based methods has shown that Gangotri glacier moves with an average displacement of 4 cm and 6 cm day-1. As present results using ERS 1/2 data were obtained for one day interval, i.e., 25th March 05:00pm to 26th March 05:00 pm, 1996, variation in displacement may be due to presence of snow or wet snow melting over the glacier, since during this time snow melt season is in progress in Gangotri glacier area. Similarly the results of glacier velocity derived using ALOSPALSAR- 2 during 22 March – 19 April 2015 shows the mean velocity of 5.4 to 7.4 cm day-1 during 28 day time interval for full glacier and main trunk glacier respectively. This L-band data is already corrected for Faraday’s rotation effects by JAXA, and tropospheric correction are also being applied to refine the results. These results are significant as it is after gap of 20 years that DInSAR methods has given glacier velocity for fast moving Himalayan glacier. RISAT-1 FRS-1 hybrid data is used to create Raney’s decompositions parameters, which are further used for glacier zones classification using support vector machine based classification method. The Radarsat-2 and ALOS-PALSAR-2 fully polarized data of year 2010 and 2015 are also used for glacier classification. The identified and classified glaciers zones in Gangotri area are debris covered ice, clean ice, percolation zone, wet snow zone, ice wall, supra-glacier lakes and moraines, similarly ice sheet features and glacier landforms such as such as nunataks, wind scoop, glacier flow paths, moraine, horn, sastrugi, and crevasses were identified in Antarctic. RISAT-1 FRS-1 data was also successful in mapping the Crevasses hidden under wind-blown ice in Antarctic’s study area.
Hydrological processes in hilly areas are complex to compute. Processes governing rainfall-runoff... more Hydrological processes in hilly areas are complex to compute. Processes governing rainfall-runoff generation, such as subsurface storm flow, saturation excess flow, overland flow, return flow and especially the pipe storage which mainly occurs in the hilly region are not taken into account by many of the popular hydrological models. Himalayan region which is hydrologically very significant region for northern and north eastern India covers around 16.2% of total geographical area. The runoff coefficient of this region is about 0.7. The rugged hill slopes of this region makes many generalized hydrological models unsuitable for computing hydrological components. So, in the present study, an attempt has been made to develop a dedicated Hillslope Hydrological Model (HHM) suitable for this region. In the developed model, the watershed area is categorized into hillslopes and plain regions. The generalized hydrological model was implemented in the plain region to estimate the runoff, however, the hillslopes are further divide into three classes namely vegetated hillslope, bare soil and settlement area. The hydrological processes in the bare soil and settlement regions are computed using Hortonian infiltration approach based on the initial moisture content and infiltration capacity of the soil. While for the vegetated hillslope region, the initial soil moisture content plays important role in computing the hydrological components. The computation is based on the water storage in the macropores for the unsaturated soil condition and on the retention excess flow for the saturated soil condition. Governing equations of all the process are integrated using the PYTHON programming language. The developed hillslope hydrological model has been tested using data from experimental plot established within the IIRS Campus. The experimental plot was designed keeping in view the natural hillslope conditions prevailing in the north western Himalayas where high intensity storm event occurs frequently. Rainfall simulators has been installed to generate the rainfall with varying intensity from 50 to 150 mm/hr. Soil moisture sensors were installed at 10 cm and 30 cm depth at different locations of the plot to observe soil moisture. Using the experimental data and the developed conceptual model the overland flow and the subsurface flow on macropore dominated area on the grid basis has been analyzed for rainfall events of varying intensity and depth. It was observed that once the soil is saturated, it remains at the field capacity level for next 24 to 36 hours. Such antecedent moisture conditions are most favorable for the generation of rapid stormflow from hillslopes. The observed discharge data from the experiment and the simulated discharge using the developed model were compared using Performance Index (PI). The value of PI of the developed model was found to be better in case of the higher intensity rainfall events compared the lower intensity events. The coefficient of determination (R2) between observed and simulated discharge for rainfall intensity of 100 mm/hr was found to be 93.64%.
Cryosphere is the second largest component of the climate system that holds around 75% of the g... more Cryosphere is the second largest component of the climate system that holds around 75%
of the global freshwater resource with important linkages and its influence on surface
energy and moisture fluxes, atmospheric and oceanic circulation. Thus, monitoring the
changes in the Cryosphere regions is very essential. Present study focuses on surrounding
areas of Schirmacher Oasis, Princess Astrid Coast located in Droning Maud Land (DML)
of East Antarctica. Land cover classification for part of DML and sea ice classification for
part of Lazarev sea near India bay was done using medium to high resolution optical and
microwave satellite images, respectively. Various classes such as Blue ice areas (BIA),
snow on BIAs, wind-blown snow, moraines, exposed hills, melt water ponds, etc were
mapped with multispectral data of Landsat-8 using supervised classification. The land
cover classes were validated by ground data collection during summer 36 ISEA to
Antarctica. Support Vector Machine, SVM based supervised image classification method
was used with Landsat 8 of 26 Nov. 2013 with the accuracy 91.87% and Kappa
coefficient is 0.89 and data of Landsat-8 dated 28 Oct. 2014 with the accuracy of 94.66%
and kappa coefficient 0.92. BIA contributed around 55 % of total area near Schirmacher
Oasis on 11 December 2016. Mapping of ice sheet, sea ice features and glacier landforms
has been carried out using high resolution datasets of Cartosat-2, RISAT-1 FRS (Fine
Resolution Strip Map), Landsat-8 (Pan) images and medium resolution data of Sentinel-1
SAR. Various ice sheet/sea ice features such as crevasses, Nunatak, Sastrugi, fast ice,
floes, ice bergs etc. were also identified, mapped and monitored using these data from
2015-2017. Identification of snow covered crevasses were also done prior to the visit to Antarctic and validated their location with high accuracy. Additionally tracking and
monitoring glacier and ice streams was also done using interferometry and feature
tracking based technique to study ice velocity using time series of optical and SAR
datasets. The ice stream velocity was estimated in the range of 5 to 60 m/year and limited
validation was done during ISEA 36 summer expedition, with highest velocity for
Somovken ice stream.
