Paper Info
Title
SMOS-IC: An Alternative SMOS Soil Moisture and Vegetation Optical Depth Product.
Abstract
The main goal of the Soil Moisture and Ocean Salinity (SMOS) mission over land surfaces is the production of global maps of soil moisture (SM) and vegetation optical depth (tau) based on multi-angular brightness temperature (TB) measurements at L-band. The operational SMOS Level 2 and Level 3 soil moisture algorithms account for different surface effects, such as vegetation opacity and soil roughness at 4 km resolution, in order to produce global retrievals of SM and t. In this study, we present an alternative SMOS product that was developed by INRA (Institut National de la Recherche Agronomique) and CESBIO (Centre d'Etudes Spatiales de la BIOsphere). One of the main goals of this SMOS-INRA-CESBIO (SMOS-IC) product is to be as independent as possible from auxiliary data. The SMOS-IC product provides daily SM and t at the global scale and differs from the operational SMOS Level 3 (SMOSL3) product in the treatment of retrievals over heterogeneous pixels. Specifically, SMOS-IC is much simpler and does not account for corrections associated with the antenna pattern and the complex SMOS viewing angle geometry. It considers pixels as homogeneous to avoid uncertainties and errors linked to inconsistent auxiliary datasets which are used to characterize the pixel heterogeneity in the SMOS L3 algorithm. SMOS-IC also differs from the current SMOSL3 product (Version 300, V300) in the values of the effective vegetation scattering albedo (omega) and soil roughness parameters. An inter-comparison is presented in this study based on the use of ECMWF (European Center for Medium range Weather Forecasting) SM outputs and NDVI (Normalized Difference Vegetation Index) from MODIS (Moderate-Resolution Imaging Spectroradiometer). A six-year (2010-2015) inter-comparison of the SMOS products SMOS-IC and SMOSL3 SM (V300) with ECMWF SM yielded higher correlations and lower ubRMSD (unbiased root mean square difference) for SMOS-IC over most of the pixels. In terms of tau, SMOS-IC t was found to be better correlated to MODIS NDVI in most regions of the globe, with the exception of the Amazonian basin and the northern mid-latitudes.
Year
DOI
Venue
2017
10.3390/rs9050457
REMOTE SENSING
Keywords
Field
DocType
SMOS,L-band,Level 3,ECMWF,SMOS-IC,soil moisture,vegetation optical depth,MODIS,NDVI
Biosphere,Vegetation,Optical depth,Brightness temperature,Remote sensing,Albedo,Normalized Difference Vegetation Index,Spectroradiometer,Geology,Weather forecasting
Journal
Volume
Issue
ISSN
9
5
2072-4292
Citations 
PageRank 
References 
9
0.55
20
Authors
10
Name
Order
Citations
PageRank
R. Fernandez1236.34
A. Al-Yaari2298.23
Arnaud Mialon326626.28
Ali Mahmoodi416613.24
Ahmad Al Bitar526126.44
Gabrielle J. M. De Lannoy6154.15
Rodriguez-Fernandez, N.7238.09
ernesto lopezbaeza8204.53
Yann Kerr913630.53
Jean-Pierre Wigneron1072077.00