Table 4 - uploaded by Chris Hopkinson
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Glacial mass balance estimated through the geodetic method requires
glacial surface coordinate observations from historical and contemporary
sources. Contemporary observations and historical topographic maps are
typically referenced to separate horizontal and vertical datums and
observed with different sampling intervals. This research demonstrates...
Context in source publication
Context 1
... geoidal undulation for profile extents along the centre of the glacial margin and a cross-section of the glacial mar- gin were obtained from GPS-H, a software package available from Natural Resources Canada which provides an interface for accessing the CGG2000 and CGG2005 geoid models. The geoidal undulation for each glacial site are presented in Table 4 and rep- 20 resent the height difference between the WGS84 (GRS-80) reference ellipsoid and the CGG2000 geoid model. The variation in geoid height is small within each glacial margin; however, larger vari- ations occur between sites. ...
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Citations
... Lastly, in anticipation of using digital topographic mapping products from historical and contemporary efforts, there is the distinct advantage that the surface elevation of the glacier can be retrieved directly and unambiguously referenced to a specific date. A necessary caution is that the geodetic referencing of the mapping products must be coregistered to obtain valid profile change data (Goulden et al., 2012(Goulden et al., , 2013. If a digital map also renders the trim line and/or lateral moraine features with adequate fidelity, then this too is an advantage, notwithstanding the cautions surrounding dating and deflation. ...
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