CGRG Bibliography of Canadian Geomorphology
Search Results
Author : Church, I.; Haigh, S.; Brucker, S.; and Hughes Clarke, J.E.
Date : 2006.
Title : Comparing GcGPS ellipsoid height records, predicted tides and a hydrodynamic circulation model for the Pond Inlet, Eclipse Sound and Navy Board Inlet system.
Publication : 3rd Annual ArcticNet Scientific Meeting. December 12-15, 2006. Victoria, British Columbia.
Issue : Abstracts Volume
Page(s) : 37.
Abstract
A vital part of precise seabed surveys is the establishment and maintenance of adequate vertical control. Tidal variations in sea-level are one of the largest sources of error in a precise bathymetric survey. Several projects within ArcticNet are interested in monitoring the inter-annual changes in seabed relief due to geological processes such as icescouring, mass-wasting, tidal scouring and bedform migration. In all cases, the scale of the vertical change in the seabed is less than ~ 1m. Thus, unless tidal influences are known or accurately modeled, scientific analysis will be hampered. One specific project is monitoring the evolution of pro-glacial deltaic sediments in Oliver Sound, Sirmilik National Park. In early September the CSL Heron conducted 4 multibeam surveys of deltaic and relict moraine sediments in front of retreating icestreams. These first surveys reveal the type of morphology, but the long term aim is to repeat these surveys annually or biannually to precisely monitor seabed change. For that we need to know the instantaneous water levels, but the logistics of installing a local tide gauge or a nearby PPK GPS station are prohibitive. Thus we are investigating three approaches: using globally-corrected GPS ellipsoid heights (GcGPS from C-Nav); using predicted water levels derived from tidal harmonics measured at stations that are within 100km; and developing a nested high- resolution (50-100m cell size) hydrodynamic grid of the constrained waters bound by B ylot Island. First results of CNav data collected from Amundsen and Heron will be compared to predicted tides and the first output of the evolving hydrodynamic model. A particular concern that we are trying to address is the scale of the change in phase and amplitude in the tide along the length of the fjord.
Bibliography of Canadian Geomorphology