TY - JOUR
T1 - Calibration of the L-MEB model over a coniferous and a deciduous forest
AU - Grant, Jennifer P.
AU - Saleh-Contell, Kauzar
AU - Wigneron, Jean-Pierre
AU - Guglielmetti, Massimo
AU - Kerr, Yann H.
AU - Schwank, Mike
AU - Skou, Niels
AU - de Griend, Adriaan A. Van
PY - 2008
Y1 - 2008
N2 - In this paper, the L-band Microwave Emission of the Biosphere (L-MEB) model used in the Soil Moisture and Ocean Salinity (SMOS) Level 2 Soil Moisture algorithm is calibrated using L-band (1.4 GHz) microwave measurements over a coniferous (Pine) and a deciduous (mixed/Beech) forest. This resulted in working values of the main canopy parameters optical depth (tau), single scattering albedo (omega), and structural parameters tt(H) and tt(V), besides the soil roughness parameters H-R and N-R. Using these calibrated values in the forward model resulted in a root mean-square error in brightness temperatures from 2.8 to 3.8 K, depending on data set and polarization. Furthermore, the relationship between canopy optical depth and leaf area index is investigated for the deciduous site. Finally, a sensitivity study is conducted for the focus parameters, temperature, soil moisture, and precipitation. The results found in this paper will be integrated in the operational SMOS Level 2 Soil Moisture algorithm and used in future inversions of the L-MEB model, for soil moisture retrievals over heterogeneous, partly forested areas.
AB - In this paper, the L-band Microwave Emission of the Biosphere (L-MEB) model used in the Soil Moisture and Ocean Salinity (SMOS) Level 2 Soil Moisture algorithm is calibrated using L-band (1.4 GHz) microwave measurements over a coniferous (Pine) and a deciduous (mixed/Beech) forest. This resulted in working values of the main canopy parameters optical depth (tau), single scattering albedo (omega), and structural parameters tt(H) and tt(V), besides the soil roughness parameters H-R and N-R. Using these calibrated values in the forward model resulted in a root mean-square error in brightness temperatures from 2.8 to 3.8 K, depending on data set and polarization. Furthermore, the relationship between canopy optical depth and leaf area index is investigated for the deciduous site. Finally, a sensitivity study is conducted for the focus parameters, temperature, soil moisture, and precipitation. The results found in this paper will be integrated in the operational SMOS Level 2 Soil Moisture algorithm and used in future inversions of the L-MEB model, for soil moisture retrievals over heterogeneous, partly forested areas.
KW - Soil Moisture and Ocean Salinity (SMOS)
KW - soil moisture
KW - forest
KW - microwave radiometry
KW - L-band
U2 - 10.1109/TGRS.2007.914801
DO - 10.1109/TGRS.2007.914801
M3 - Journal article
SN - 0196-2892
VL - 46
SP - 808
EP - 818
JO - IEEE Transactions on Geoscience and Remote Sensing
JF - IEEE Transactions on Geoscience and Remote Sensing
IS - 3
ER -