Evaluation Of The Potential Of C- And X-band Sar Data To Monitor Dry And Wet Snow Cover

2005 ◽  
Author(s):  
M. Bernier ◽  
J. Fortin
Keyword(s):  
Snow Cover ◽  
X Band ◽  
Wet Snow ◽  
Sar Data

Wet Snow Cover Mapping Algorithm Based on Multitemporal COSMO-SkyMed X-Band SAR Images

2012 ◽  
Vol 5 (3) ◽  
pp. 1045-1053 ◽  
Author(s):  
Thomas Schellenberger ◽  
Bartolomeo Ventura ◽  
Marc Zebisch ◽  
Claudia Notarnicola
Keyword(s):  
Snow Cover ◽  
Sar Images ◽  
Mapping Algorithm ◽  
X Band ◽  
Wet Snow

scholarly journals TerraSAR-X Time Series Fill a Gap in Spaceborne Snowmelt Monitoring of Small Arctic Catchments—A Case Study on Qikiqtaruk (Herschel Island), Canada

2018 ◽  
Vol 10 (7) ◽  
pp. 1155 ◽  
Author(s):  
Samuel Stettner ◽  
Hugues Lantuit ◽  
Birgit Heim ◽  
Jayson Eppler ◽  
Achim Roth ◽  
...  
Keyword(s):  
Snow Cover ◽  
Spatiotemporal Variability ◽  
Accurate Estimation ◽  
Landsat 8 ◽  
Snowmelt Period ◽  
X Band ◽  
Data Gaps ◽  
Wet Snow ◽  
Positive Threshold

The timing of snowmelt is an important turning point in the seasonal cycle of small Arctic catchments. The TerraSAR-X (TSX) satellite mission is a synthetic aperture radar system (SAR) with high potential to measure the high spatiotemporal variability of snow cover extent (SCE) and fractional snow cover (FSC) on the small catchment scale. We investigate the performance of multi-polarized and multi-pass TSX X-Band SAR data in monitoring SCE and FSC in small Arctic tundra catchments of Qikiqtaruk (Herschel Island) off the Yukon Coast in the Western Canadian Arctic. We applied a threshold based segmentation on ratio images between TSX images with wet snow and a dry snow reference, and tested the performance of two different thresholds. We quantitatively compared TSX- and Landsat 8-derived SCE maps using confusion matrices and analyzed the spatiotemporal dynamics of snowmelt from 2015 to 2017 using TSX, Landsat 8 and in situ time lapse data. Our data showed that the quality of SCE maps from TSX X-Band data is strongly influenced by polarization and to a lesser degree by incidence angle. VH polarized TSX data performed best in deriving SCE when compared to Landsat 8. TSX derived SCE maps from VH polarization detected late lying snow patches that were not detected by Landsat 8. Results of a local assessment of TSX FSC against the in situ data showed that TSX FSC accurately captured the temporal dynamics of different snow melt regimes that were related to topographic characteristics of the studied catchments. Both in situ and TSX FSC showed a longer snowmelt period in a catchment with higher contributions of steep valleys and a shorter snowmelt period in a catchment with higher contributions of upland terrain. Landsat 8 had fundamental data gaps during the snowmelt period in all 3 years due to cloud cover. The results also revealed that by choosing a positive threshold of 1 dB, detection of ice layers due to diurnal temperature variations resulted in a more accurate estimation of snow cover than a negative threshold that detects wet snow alone. We find that TSX X-Band data in VH polarization performs at a comparable quality to Landsat 8 in deriving SCE maps when a positive threshold is used. We conclude that TSX data polarization can be used to accurately monitor snowmelt events at high temporal and spatial resolution, overcoming limitations of Landsat 8, which due to cloud related data gaps generally only indicated the onset and end of snowmelt.

scholarly journals A Classification Scheme for Sediments and Habitats on Exposed Intertidal Flats with Multi-Frequency Polarimetric SAR

2021 ◽  
Vol 13 (3) ◽  
pp. 360
Author(s):  
Wensheng Wang ◽  
Martin Gade ◽  
Kerstin Stelzer ◽  
Jörn Kohlus ◽  
Xinyu Zhao ◽  
...  
Keyword(s):  
Classification Scheme ◽  
Wadden Sea ◽  
Relative Difference ◽  
Polarimetric Synthetic Aperture Radar ◽  
Intertidal Flats ◽  
Sediment Types ◽  
X Band ◽  
Good Potential ◽  
L Band ◽  
Sar Data

We developed an extension of a previously proposed classification scheme that is based upon Freeman–Durden and Cloude–Pottier decompositions of polarimetric Synthetic Aperture Radar (SAR) data, along with a Double-Bounce Eigenvalue Relative Difference (DERD) parameter, and a Random Forest (RF) classifier. The extension was done, firstly, by using dual-copolarization SAR data acquired at shorter wavelengths (C- and X-band, in addition to the previously used L-band) and, secondly, by adding indicators derived from the (polarimetric) Kennaugh elements. The performance of the newly developed classification scheme, herein abbreviated as FCDK-RF, was tested using SAR data of exposed intertidal flats. We demonstrate that the FCDK-RF scheme is capable of distinguishing between different sediment types, namely mud and sand, at high spatial accuracies. Moreover, the classification scheme shows good potential in the detection of bivalve beds on the exposed flats. Our results show that the developed FCDK-RF scheme can be applied for the mapping of sediments and habitats in the Wadden Sea on the German North Sea coast using multi-frequency and multi-polarization SAR from ALOS-2 (L-band), Radarsat-2 (C-band) and TerraSAR-X (X-band).

Potential and limitations of RADARSAT SAR data for wet snow monitoring

2000 ◽  
Vol 38 (1) ◽  
pp. 316-320 ◽  
Author(s):  
N. Baghdadi ◽  
Y. Gauthier ◽  
M. Bernier ◽  
J.-P. Fortin
Keyword(s):  
Wet Snow ◽  
Sar Data

scholarly journals Discrimination of glacier facies using multi-temporal SAR data

1998 ◽  
Vol 44 (146) ◽  
pp. 42-53 ◽  
Author(s):  
K. C. Partington
Keyword(s):  
European Space Agency ◽  
Greenland Ice Sheet ◽  
Sensor Calibration ◽  
Lower Altitude ◽  
Mount Pinatubo ◽  
South Central ◽  
Space Agency ◽  
Wet Snow ◽  
Multi Temporal ◽  
Sar Data

AbstractGlacier facies from the Greenland ice sheet and the Wrangell-St Elias Mountains, Alaska, are analyzed using multi-temporal synthetic aperture radar (SAR) data from the European Space Agency ERS-1 satellite. Distinct zones and facies are visible in multi-temporal SAR data, including the dry-snow facies, the combined percolation and wet-snow facies, the ice facies, transient melt areas and moraine. In Greenland and south-central Alaska, very similar multi-temporal signatures are evident for the same facies, although these facies are found at lower altitude in West Greenland where the equilibrium line appears to be found at sea level at 71°30?N during the year analyzed (1992-93), probably because of the cooling effect of the eruption of Mount Pinatubo. In Greenland, both the percolation and dry-snow facies are excellent distributed targets for sensor calibration, with backscatter coefficients stable to within 0.2 dB. However, the percolation facies near the top of Mount Wrangell are more complex and less easily delineated than in Greenland, and at high altitude the glacier facies have a multi-temporal signature which depends sensitively on slope orientation.

Snow Cover Monitoring by Synergistic Use of Sentinel-3 Slstr and Sentinel-L Sar Data

2018 ◽  
Author(s):  
Thomas Nagler ◽  
Helmut Rott ◽  
Joanna Ossowska ◽  
Gabriele Schwaizer ◽  
David Small ◽  
...  
Keyword(s):  
Snow Cover ◽  
Sar Data
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