of applications (e.g. Mitchell and Chadwick, 1998; Mills et al., 
2005). This is an automated technique which minimises 
differences between overlapping DEMs by establishing point- 
to-point or point-to-surface correspondences. Previous research 
at Newcastle University has resulted in the development of a 
robust matching algorithm, which has been shown to perform 
well in the context of glacier change estimation in the Svalbard 
archipelago, Norway (Miller et al., 2009). The scale-stability of 
DEMsS derived from ASTER satellite imagery appears to offer a 
solution for the registration of DEMs extracted from archival 
aerial imagery, overcoming the requirement for ground control 
and, at the same time, allows for historical ice volume change to 
be robustly determined (Miller et al., 2009). 
In the research presented here, DEMs extracted from USGS 
archive stereo-photography of the AP are registered to DEMs 
derived from modern ASTER data and aerial photography by 
means of robust surface matching. A case study examining 
multi-decadal glacial volume change for two glaciers within the 
AP is presented, and the results are assessed to evaluate the 
potential of this approach for wider implementation through 
future work. 
2. DATASETS AND TEST SITES 
The USGS Earth Resources and Observation and Science 
(EROS) Data Centre holds a collection of over 330,000 single 
frame records of Antarctica from 1946-present. The data is 
freely available online via EarthExplorer 
(earthexplorer.usgs.gov). From this archive a minimum of three 
overlapping images was selected, for two sites in the western 
Antarctic Peninsula, with sufficient image contrast and clearly 
identifiable stable terrain to optimise the reliability of 
subsequently extracted DEMs. 
  
Figure 1: Antarctica Single Frame Record from January 1969 
(nadir image, O USGS) 
Most of these archive images were acquired by the U.S. Navy 
with a trimetrogon sensor configuration. This configuration is 
highly suited to rapid topographic mapping and consists of one 
nadir looking photograph, which is of particular interest here 
(Figure 1), and two oblique looking photographs, with all three 
acquired simultaneously. To enable their use within modern 
digital photogrammetric workstations and to preserve 
information for future generations these single frame images 
have been scanned and converted to digital image format by the 
EROS Data Center. In this study the highest resolution scans, 
25 microns (1000 dpi), were utilised. The original format size is 
approximately 9 x 9 inches. Metadata information is available 
but limited. Each frame has associated information relating to 
the focal length, lens type and acquisition date. Although the 
calibrated focal length and lens distortion parameters were 
available, more detailed camera calibration information was 
lacking. The only available calibration information was that 
found in a report on the calibration of military cameras (Spriggs 
1966). Ground control points (GCPs) were not available. Hence 
the photogrammetric processing of this data is not 
straightforward. 
, 
, 
The selected USGS image frames cover the front of Nemo 
glacier (January 1969; Figure 1), located approximately 
67.33 °W and 67.71 °S on Pourquoi Pas Island, and the front of 
Leonardo glacier (November 1968), located approximately 
61.91 °W and 64.68 °S. Both glaciers can be classified as 
marine terminating glaciers and are highly crevassed at the front. 
The surrounding terrain is steep and mountainous, which is 
typically for most of the Antarctic Peninsula. 
As reference data for the for the Leonardo glacier site, modern 
ASTER satellite imagery (November 2001) was used. ASTER 
provides a favourable source of data for glaciological studies 
because it allows mapping in the visible, the near-infrared and 
the thermal parts of the electromagnetic spectrum. Importantly, 
it provides near global coverage, to + 82° latitude which makes 
ASTER particularly attractive for polar studies. With a spatial 
resolution of up to 15 m, ASTER also offers relatively detailed 
analysis of surface processes. Utilising the along-track nadir 
viewing (band 3N) and backward viewing (band 3B, 27.7° off- 
nadir) imagery in the near-infrared portion of the spectrum, 
DEMs can be generated and ortho-images directly extracted. 
The ASTER data was downloaded from NASA's Land 
Processes Distributed Active Archive Center (LP DAAC). For 
Nemo glacier present-day (February 2005) aerial stereo- 
photography with an accompanying 2 m DEM was available 
and provided by BAS. For this data, full camera calibration 
information was available. 
3. DEM EXTRACTION 
The ASTER data was processed in /TT ENVI 4.6.1 and the 
DEM was generated from Level 1B data (Band 3N & 3B) with 
the additional DEM Extraction Module (Version 4.7). A 
minimum of 50 tie points between the stereo image pair was 
automatically generated. The generated tie-points were 
examined individually and manually corrected or removed if 
necessary. The output resolution was set to 15 m. Given that no 
ground control data was available, relative DEMSs, based on the 
sensor attitude and ephemeris data were produced and projected 
into UTM coordinates based on the WGS-84 ellipsoid. 
     
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