scholarly journals Modelling the delivery of supraglacial meltwater to the ice/bed interface: application to southwest Devon Ice Cap, Nunavut, Canada

2012 ◽  
Vol 58 (208) ◽  
pp. 361-374 ◽  
Author(s):  
Caroline Clason ◽  
Douglas W.F. Mair ◽  
David O. Burgess ◽  
Peter W. Nienow
Keyword(s):  
Drainage System ◽  
Ice Thickness ◽  
Ice Cap ◽  
Distributed Modelling ◽  
Spatially Distributed ◽  
Devon Ice Cap ◽  
Climatic Scenarios ◽  
Lake Drainage ◽  
Fully Coupled

AbstractThe transfer of surface-generated meltwater to the subglacial drainage system through full ice thickness crevassing may lead to accelerated glacier velocities, with implications for ice motion under future climatic scenarios. Accurate predictions of where surface meltwater accesses the ice/bed interface are therefore needed in fully coupled hydrodynamic ice-sheet models. We present a spatially distributed modelling routine for predicting the location and timing of delivery of surface-derived meltwater to the ice/bed interface through moulins and supraglacial lake drainage. The model is explained as it is applied to the Croker Bay glacial catchment of Devon Ice Cap, Canada. The formation of moulins, drainage of lakes, and the transfer of meltwater through the full ice thickness are modelled for the 2004 and 2006 ablation seasons. Through this case study we assess the model’s sensitivity to degree-day factors, fracture toughness, tensile strength and crevasse width, and confirm that parameters influencing the rate at which water fills a crevasse are the most significant controls on the ability of a crevasse to reach the bed. Increased surface melt production, therefore, has the potential to significantly influence the spatial and temporal transfer of meltwater through surface-to-bed connections in a warmer climate

scholarly journals Variability in ice motion and dynamic discharge from Devon Ice Cap, Nunavut, Canada

2017 ◽  
Vol 63 (239) ◽  
pp. 436-449 ◽  
Author(s):  
WESLEY VAN WYCHEN ◽  
JAMIE DAVIS ◽  
LUKE COPLAND ◽  
DAVID O. BURGESS ◽  
LAURENCE GRAY ◽  
...  
Keyword(s):  
Feature Tracking ◽  
Ice Thickness ◽  
Tidewater Glaciers ◽  
Bed Topography ◽  
Ice Cap ◽  
The North ◽  
Landsat 7 ◽  
Devon Ice Cap ◽  
Dynamic Discharge ◽  
Observation Period

ABSTRACTFeature tracking of approximately annually separated Landsat-7 ETM+ imagery acquired from 1999 to 2010 and speckle tracking of 24-day separated RADARSAT-2 imagery acquired from 2009 to 2015 reveal that motion of the major tidewater glaciers of Devon Ice Cap is more variable than previously described. The flow of almost half (six of 14) of the outlet glaciers slowed over the observation period, while that of the terminus regions of three of 14 of the glaciers sped up in the most recent years of observation. The North Croker Bay Glacier of southern Devon Ice Cap showed the greatest variability in motion, oscillating between multi-year (three or more) periods of slower and faster flow and exhibited a pattern of velocity variability that is different from that of the rest of the ice cap's outlet glaciers. Comparisons between areas of dynamic variability and glacier bed topography indicate that velocity variability is largely restricted to regions where the glacier bed is grounded below sea level. Derived velocities are combined with measurements of ice thickness at the fronts of tidewater glacier to determine a mean annual (2009; 2011–15) dynamic ice discharge of 0.41 ± 0.11 Gt a−1for Devon Ice Cap. The Belcher Glacier is becoming a larger source of mass loss via ice discharge.

scholarly journals Spatially distributed modelling of surface water-groundwater exchanges during overbank flood events – a case study at the Garonne River

2016 ◽  
Vol 94 ◽  
pp. 146-159 ◽  
Author(s):  
Léonard Bernard-Jannin ◽  
David Brito ◽  
Xiaoling Sun ◽  
Eduardo Jauch ◽  
Ramiro Neves ◽  
...  
Keyword(s):  
Surface Water ◽  
Flood Events ◽  
Distributed Modelling ◽  
Garonne River ◽  
Spatially Distributed

scholarly journals Linking surface hydrology to flow regimes and patterns of velocity variability on Devon Ice Cap, Nunavut

2015 ◽  
Vol 61 (226) ◽  
pp. 387-399 ◽  
Author(s):  
Faye R. Wyatt ◽  
Martin J. Sharp
Keyword(s):  
Drainage System ◽  
System Structure ◽  
Surface Velocity ◽  
Point Distribution ◽  
Drainage Systems ◽  
Ice Cap ◽  
Basal Sliding ◽  
Landsat 7 ◽  
Devon Ice Cap ◽  
Glacier Flow

AbstractSupraglacial meltwater reaching a glacier bed can increase ice surface velocities via hydraulic jacking and enhanced basal sliding. However, the relationships between the structure of supraglacial drainage systems, sink-point distributions, glacier flow processes and the magnitude of interannual velocity variability are poorly understood. To explore the hypothesis that spatial variations in the rate and mechanisms of glacier flow are linked to variations in supraglacial drainage system structure and sink-point distribution across an ice cap, we mapped supraglacial drainage systems on Devon Ice Cap from Landsat-7 ETM+ imagery. Spatial patterns of surface velocity and interannual velocity variability were determined using gradient correlation applied to Landsat-7 ETM+ images. Velocity variability is greater in areas close to sink-point locations, presumably because hydrologically forced basal sliding and/or bed deformation are enhanced in such areas. The distribution and characteristics of supraglacial drainage systems may play an important role in determining the distribution of regions of basal sliding, highlighting the need for knowledge of the supraglacial drainage system structure and sink-point distribution to inform efforts to model the dynamic response of Arctic ice caps to future climate warming.

A study on the effects of urban runoff controls in the sandsli research catchment, Bergen, Norway

1997 ◽  
Vol 36 (8-9) ◽  
pp. 379-384
Author(s):  
Sveinn T. Thorolfsson
Keyword(s):  
Ground Water ◽  
Stormwater Management ◽  
Drainage System ◽  
Urban Runoff ◽  
Source Control ◽  
Urban Stormwater ◽  
Urban Stormwater Management ◽  
Water Conditions

This paper describes a case study on a new alternative drainage system for urban stormwater management, the so-called “Sandsli-system”. The aim of this study is to evaluate the Sandsli system and the effects of the solution on ground water conditions. The study is carried out in the Sandsli research catchment in Bergen, Norway. The idea behind the “Sandsli-system is not to mix the polluted and the clean stormwater combined with a source control for both stormwater quantity and quality. The clean stormwater is percolated as quickly as possible, while the polluted stormwater is collected and conducted to an appropriate site for disposal or treatment. The Sandsli-system was developed as an alternative drainage system to the conventional drainage system. The system has been functioning satisfactorily since 1981 to date. The advantages of the use of the Sandsli-system is highlighted i.e. recharging the stormwater to the ground water. The Sandsli-system is appropriate to locations with climate and geology similar to that found in the coastal part of Norway

Spatially distributed soil losses and sediment yield: a case study of Langat watershed, Selangor, Malaysia

2021 ◽  
pp. 104742
Author(s):  
Noor Fadzilah Yusof ◽  
Tukimat Lihan ◽  
Wan Mohd Razi Idris ◽  
Zulfahmi Ali Rahman ◽  
Muzneena Ahmad Mustapha ◽  
...  
Keyword(s):  
Sediment Yield ◽  
Spatially Distributed ◽  
Soil Losses

scholarly journals Toward Decentralised Sanitary Sewage Collection Systems: A Multiobjective Approach for Cost-Effective and Resilient Designs

Water ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 1886
Author(s):  
Arezoo Zahediasl ◽  
Amin E. Bakhshipour ◽  
Ulrich Dittmer ◽  
Ali Haghighi
Keyword(s):  
Treatment Plant ◽  
Drainage System ◽  
Cost Effective ◽  
Optimization Approach ◽  
Hydraulic Design ◽  
Multiobjective Approach ◽  
Layout Generation ◽  
Plant Allocation ◽  
Problem Solving Process

In recent years, the concept of a centralized drainage system that connect an entire city to one single treatment plant is increasingly being questioned in terms of the costs, reliability, and environmental impacts. This study introduces an optimization approach based on decentralization in order to develop a cost-effective and sustainable sewage collection system. For this purpose, a new algorithm based on the growing spanning tree algorithm is developed for decentralized layout generation and treatment plant allocation. The trade-off between construction and operation costs, resilience, and the degree of centralization is a multiobjective problem that consists of two subproblems: the layout of the networks and the hydraulic design. The innovative characteristics of the proposed framework are that layout and hydraulic designs are solved simultaneously, three objectives are optimized together, and the entire problem solving process is self-adaptive. The model is then applied to a real case study. The results show that finding an optimum degree of centralization could reduce not only the network’s costs by 17.3%, but could also increase its structural resilience significantly compared to fully centralized networks.

scholarly journals Ice thickness and volume of the Renland Ice Cap, East Greenland

2021 ◽  
pp. 1-13
Author(s):  
Iben Koldtoft ◽  
Aslak Grinsted ◽  
Bo M. Vinther ◽  
Christine S. Hvidberg
Keyword(s):  
Surface Topography ◽  
Climate Model ◽  
Thickness Distribution ◽  
High Elevation ◽  
Surface Velocity ◽  
Ice Thickness ◽  
Model Parameters ◽  
East Greenland ◽  
Ice Volume ◽  
Ice Cap

Abstract To assess the amount of ice volume stored in glaciers or ice caps, a method to estimate ice thickness distribution is required for glaciers where no direct observations are available. In this study, we use an existing inverse method to estimate the bedrock topography and ice thickness of the Renland Ice Cap, East Greenland, using satellite-based observations of the surface topography. The inverse approach involves a procedure in which an ice dynamical model is used to build-up an ice cap in steady state with climate forcing from a regional climate model, and the bedrock is iteratively adjusted until the modelled and observed surface topography match. We validate our model results against information from airborne radar data and satellite observed surface velocity, and we find that the inferred ice thickness and thereby the stored total volume of the ice cap is sensitive to the assumed ice softness and basal slipperiness. The best basal model parameters for the Renland Ice Cap are determined and the best estimated total ice volume of 384 km3 is found. The Renland Ice Cap is particularly interesting because of its location at a high elevation plateau and hence assumed low sensitivity to climate change.

scholarly journals Hydraulic transmissivity inferred from ice-sheet relaxation following Greenland supraglacial lake drainages

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Ching-Yao Lai ◽  
Laura A. Stevens ◽  
Danielle L. Chase ◽  
Timothy T. Creyts ◽  
Mark D. Behn ◽  
...  
Keyword(s):  
Laboratory Experiments ◽  
Ice Sheet ◽  
Drainage System ◽  
Greenland Ice Sheet ◽  
Field Observations ◽  
Surface Uplift ◽  
Drainage Networks ◽  
Order Of Magnitude ◽  
Lake Drainage ◽  
Magnitude Increase

AbstractSurface meltwater reaching the base of the Greenland Ice Sheet transits through drainage networks, modulating the flow of the ice sheet. Dye and gas-tracing studies conducted in the western margin sector of the ice sheet have directly observed drainage efficiency to evolve seasonally along the drainage pathway. However, the local evolution of drainage systems further inland, where ice thicknesses exceed 1000 m, remains largely unknown. Here, we infer drainage system transmissivity based on surface uplift relaxation following rapid lake drainage events. Combining field observations of five lake drainage events with a mathematical model and laboratory experiments, we show that the surface uplift decreases exponentially with time, as the water in the blister formed beneath the drained lake permeates through the subglacial drainage system. This deflation obeys a universal relaxation law with a timescale that reveals hydraulic transmissivity and indicates a two-order-of-magnitude increase in subglacial transmissivity (from 0.8 ± 0.3 $${\rm{m}}{{\rm{m}}}^{3}$$ m m 3 to 215 ± 90.2 $${\rm{m}}{{\rm{m}}}^{3}$$ m m 3 ) as the melt season progresses, suggesting significant changes in basal hydrology beneath the lakes driven by seasonal meltwater input.

Study on Implementation of ITK Campus Drainage Master Plan (Case Study: Faculty of Mathematics and Natural Sciences)

2021 ◽  
Vol 104 ◽  
pp. 47-56
Author(s):  
Rossana Margaret Kadar Yanti ◽  
Oryza Lhara Sari ◽  
Rizjal Wahyu
Keyword(s):  
Teaching And Learning ◽  
Drainage System ◽  
Natural Sciences ◽  
Learning Activities ◽  
Master Plan ◽  
Institute Of Technology ◽  
Under Construction ◽  
Runoff Discharge ◽  
Technology Area

Two main building Kalimantan Institute of Technology was established on an area of 3500 m2 on October 6, 2014 which serves as the infrastructure for teaching and learning activities of students. The rapid increase in the number of students each year results in an increase in the number of buildings as facilities for teaching and learning. This is the background for the development of the Kalimantan Institute of Technology area by adding five more lecture buildings to support teaching and learning activities for 3500 students. The expansion area for five more lecture buildings is currently under construction in the area of ​​the Faculty of Mathematics and Natural Sciences. The function of the land area has been change due to building construction resulted in an increase in runoff discharge. This condition certainly affects the region if not handled properly. Increased runoff discharge will affect inundation or flooding in the area if it is not equipped with a drainage system as needed. This research is one alternative solution given. This research is in the form of a study on the implementation of a drainage master plan that aims to obtain drainage dimensions such as drainage width, drainage length and drainage depth by observing runoff due to rainwater using the concept of environmentally friendly drainage. The research obtained from the dimensions of tertiary canals with dimensions of 0.10-0.30 meters, secondary channels 0.30-0.45 meters and primary channels 0.35-0.70 meters with the discharge area of ​​the Faculty of Mathematics and Natural Sciences ITK is 1.18 m3/ sec.

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