Synthetic Aperture Radar (SAR) delivers high-resolution radar images day or night, and in all weather conditions. It also
offers the capability for penetrating materials. These unique capabilities boost the application of SAR remote sensing
techniques in Antarctica. Based on the key area of Chinese National Antarctic Research Expedition (CHINARE) -
PANDA (Prydz Bay, Amery Ice Shelf and Dome A) section, this paper summarized the typical applications of SAR data,
and discussed the crevasse detection with semi-variance analysis in the SAR images of the Grove Mountains area, DEM
generation with InSAR pairs and ICESat GLAS data of the Grove Mountains area and nearby areas, and ice flow
velocity derivation from D-InSAR and offset tracking of the Grove Mountains area and downstream areas in East
Antarctica. The studies provide important information for Antarctic fieldwork and scientific researches. It is further
confirmed that Synthetic Aperture Radar remote sensing has tremendous potential in the field of glacial geomorphology,
topographic mapping and glacier dynamics, etc.
Ionospheric abnormality before the 26 December 2004 M9.3 Sumatra earthquake is detected by the total electron content
(TEC) of ground-based receivers of the global positioning system (GPS) in the Indian Ocean area. Higher spatiotemporal
grids of VTEC than earlier research are computed. To identify the abnormal ionospheric-seismic signals before
the earthquake, a method of statistical analysis is utilized, and the temporal solar activity and geomagnetic environment
is also considered in this paper. Results indicate that VTECs mostly decreased 4 days before earthquake happening, and
quickly come back after the tragedy. We also find that areas of ionospheric-seismic anomalies is in ±15° latitude deviate
from epicenter, and the anomalies are more obvious in the sea than the earth, so we can deduce that correlations of
ionosphere with seabed and earth are different to some extent.
The Lambert Glacier-Amery Ice Shelf (LAS) system is the largest glacier-ice-shelf system in East Antarctica, the Amery Ice Shelf (AIS) and its tributaries drain ice from the LAS system. During the austral summer season of 2002/03, the 19th Chinese National Antarctica Research Expedition (CHINARE) carried out the first expedition on the Amery Ice Shelf and set up 7 GPS sites, During the austral summer season of 2003/04, the 20th Chinese National Antarctica Research Expedition (CHINARE) cooperated with Australian National Antarctica Research Expedition (ANARE) visited the Amery Ice Shelf again, 5 GPS sites were reoccupied. The GPS data were processed using the GAMIT/GLOBK software, and the surface ice velocities was calculated. Results show that surface horizontal velocities at the 5 GPS sites at the front of the Amery Ice Shelf vary between 900m/y and 1600m/y. Such studies are fundamental to improving our knowledge of the Antarctic ice sheet mass balance and dynamical models of ice/ocean interaction.
The paper researches texture extraction using wavelet transform. After introducing the wavelet transform and the texture analysis methods, the image is decomposed by wavelet transform, and the sub-images are gained. Secondly, the paper takes entropy and mean as texture parameter, so the texture image is an entropy or mean image. Finally, the image is classified by the spectral and texture information. The size of the texture calculating window and the treatment to the sub-image are researched in this paper. On condition that the spectral classification adding with texture feature, the precision will improve 4% averagely. Wavelet transform can decomposed image at several levels, so it can provide many information to classify and extract, which is helpful to those applications. Because of the texture window, texture image has fuzzy edge, it will lead to error for the image that have fine object or the area with different objects interleaved.
Image fusion is an important content for digital image processing. For the past research, the method would be good at either the low frequency information or the high frequency information. For example, the fusion method based on high-pass filter of wavelet transform (HPFWT) is good at retaining detail information, and the method based on local deviation of wavelet transform (LDWT) is specialize in preserving multi-spectral information. It would be great if the two methods are combined. Therefore, the paper combines local deviation and high-pass filter to fuse image. The result indicates that this method can improve the detail information comparing with LDWT, enhance the spectral information comparing with HPFWT.
Synthetic aperture radar interferometry has been proposed as a potential technique for digital elevation model (DEM) generation, topographic mapping, and surface motion detection especially in the inaccessible areas. Grove Mountains Area locates to the southwest of Princess Elizabeth Land, inland areas of east Antarctica. The topographical map of the core area (11 x 10 KM2) was printed after the field surveying with GPS and total station was finished under the atrocious weather conditions during the 16th CHINARE (Chinese National Antarctic Research Expedition) 1999/2000. This paper will present an experimental investigation of the ERS-1/2 SAR tandem data in 1996 on DEM generation of the Grove Mountains Core Area, analyze the data processing, and compare the DEM with the actual topographic form. It is confirmed that InSAR is a very useful technique to be utilized in Antarctica, and can be used to produce more products instead of dagnerous field surveying.