Conclusions
The exercises show that the microwave backscatter of ice and snow can vary a lot over time and across one image. The backscatter intensity gives information about the current snow and ice conditions, such as their wetness and roughness.
Radar remote sensing can therefore be used to study snow and ice conditions. However, these conditions may change quickly, depending on the meteorological situation of the area (e.g. temperature, rain, snow). It is difficult to map glaciers from one radar image only. However, a combination of images taken at different times and from the same orbit-track (multitemporal composites) help locate glacier boundaries.
Satellite sensors used in this case study
| Sensor | Type | Spatial resolution (size of one image pixel) | | ALOS PALSAR | SAR sensor, wavelength 23.6 cm | 7 – 100 m (depending on acquisition mode) | | ASTER | Multispectral optical cameras; visible, near infrared, shortwave infrared, thermal infrared, stereo | 15, 30, and 90 m | | Envisat ASAR | SAR sensor, wavelength 5.6 cm | 20 m and coarser (depending on acquisition mode) | | Landsat TM and ETM+ | Multispectral optical cameras; visible, near infrared, shortwave infrared, thermal infrared | 15, 30, and 60 m | | MODIS | Multispectral optical camera; visible, near infrared, shortwave infrared, thermal infrared | 250, 500, 1000 m |
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Last update: 23 January 2014
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Glacier analysis using radar imagery
| | • | Introduction (http://www.esa.int/SPECIALS/Eduspace_Global_EN/SEMFYU96KQH_0.html) | |
Background
| | • | Radar (http://www.esa.int/SPECIALS/Eduspace_Global_EN/SEMD4V96KQH_0.html) | | | • | Synthetic Aperture Radar (SAR) (http://www.esa.int/SPECIALS/Eduspace_Global_EN/SEMFMY96KQH_0.html) | |
Exercises
| | • | Worksheet introduction (http://www.esa.int/SPECIALS/Eduspace_Global_EN/SEMZSY96KQH_0.html) | | | • | Exercise 1: Multitemporal radar and multispectral optical data (http://www.esa.int/SPECIALS/Eduspace_Global_EN/SEMPZY96KQH_0.html) | | | • | Exercise 2: The influence of weather conditions on radar imagery (http://www.esa.int/SPECIALS/Eduspace_Global_EN/SEM7DZ96KQH_0.html) | |
Eduspace - Software
| | • | LEOWorks 4 (MacOS) (http://leoworks.asrc.ro/download/leoworks.app.zip) | | | • | LEOWorks 4 (Windows) (http://leoworks.asrc.ro/download/leoworks.exe) | | | • | LEOWorks 4 (Linux) (http://leoworks.asrc.ro/download/leoworks.jar) | |
Eduspace - Download
| | • | Images_Glaciers.zip (http://esamultimedia.esa.int/eduspace/Leoworks-material.zip) | | | • | GoogleEarth file (http://esamultimedia.esa.int/eduspace/GoogleEarth_file.kmz) | |
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