10.5880/TR32DB.KGA92.9
Koyama, Christian N.
Christian N.
Koyama
https://orcid.org/0000-0003-3469-9764
University of Cologne, Institute of Geography
Fiener, Peter
Peter
Fiener
https://orcid.org/0000-0001-6244-4705
University of Cologne, Institute of Geography
Schneider, Karl
Karl
Schneider
https://orcid.org/0000-0002-4381-2151
University of Cologne, Institute of Geography
Soil moisture estimation under vegetation from PALSAR FBD data by means of polarimetric decomposition techniques
Geographisches Institut der Universität zu Köln - Kölner Geographische Arbeiten
2011
Book Section
Other
None
ALOS
PALSAR
Polarimetry
Soil Moisture
Vegetation
Surface Roughness
Lenz-Wiedemann, Victoria
Victoria
Lenz-Wiedemann
University of Cologne, Institute of Geography
Bareth, Georg
Georg
Bareth
http://www.researcherid.com/rid/F-3641-2015
University of Cologne, Institute of Geography
Transregional Collaborative Research Centre 32, Meteorological Institute, University Of Bonn
University Of Cologne, Regional Computing Centre (RRZK)
2011
en
0454-1294
1686 Kilobytes
8 Pages
PDF
1
Creative Commons Attribution 4.0 International
Proceedings on the Workshop of Remote Sensing Methods for Change Detection and Process Modelling, 18-19 November 2010, pp. 63-70
The disturbing effects caused by vegetation and surface roughness are major impediments to accurate quantitative retrievals of soil moisture from Synthetic Aperture Radar (SAR). With most of the operational spaceborne systems it is not possible to separate the different scattering contributions of the soil and vegetation components. In this study we use the coherent-on-receive dual-pol standard acquisitions (FBD343) of Phased Array type L-band Synthetic Aperture Radar (PALSAR) aboard the Advanced Land Observing Satellite (ALOS 'Daichi') acquired over an arable land test site in Western Germany. By applying a PolSAR decomposition technique, namely the H/A/Alpha decomposition, we exploit the phase information to increase the amount of observables. The potential to derive information on biomass and surface roughness from the dual-pol data is investigated based on correlation analyses between PALSAR observables and in-situ measurements. High sensitivities towards surface roughness and crop biomass could be ascertained. Using these findings, we estimate surface roughness ks and sugar beet total wet weight with RMS errors of 0.11 and 2.66 kg/m?, respectively. The good quality of the estimates allows correcting the backscattering coefficients for the surface roughness and vegetation effects. The accuracy of soil moisture retrievals could be increased from 4.5 to 3.6 Vol.-% using the roughness correction for bare soil and from > 10.0 to 3.6 Vol.-% using the biomass correction for sugar beet. The results give a promising outlook in terms of the possibility to develop an operational soil moisture retrieval model for PALSAR data collected in the Fine Beam Dual Polarization (FBD) mode.
Proceedings on the Workshop of Remote Sensing Methods for Change Detection and Process Modelling, 18-19 November 2010, University of Cologne, Germany, Kölner Geographische Arbeiten, 92, pp. 63-70