Retrieval of Soil Moisture and Vegetation Canopy Parameters With L- band Radar for a Range of Boreal Forests Alireza Tabatabaeenejad, Mariko Burgin , and Mahta Moghaddam Radiation Laboratory Department of Electrical Engineering and Computer Science University of Michigan Ann Arbor, MI, USA
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Alireza Tabatabaeenejad, Mariko Burgin , and Mahta Moghaddam Radiation Laboratory
Retrieval of Soil Moisture and Vegetation Canopy Parameters With L-band Radar for a Range of Boreal Forests. Alireza Tabatabaeenejad, Mariko Burgin , and Mahta Moghaddam Radiation Laboratory Department of Electrical Engineering and Computer Science University of Michigan Ann Arbor, MI, USA. - PowerPoint PPT Presentation
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Retrieval of Soil Moisture and Vegetation Canopy Parameters With L-
band Radar for a Range of Boreal Forests
Alireza Tabatabaeenejad, Mariko Burgin, and Mahta Moghaddam
Radiation LaboratoryDepartment of Electrical Engineering and Computer Science
University of MichiganAnn Arbor, MI, USA
Introduction (1/3)
Soil Moisture is of fundamental
importance to the study and
understanding of
Cycling of Water & Energy,
Runoff Potential, Flood Control
Weather and Climate
Geotechnical Engineering,
Soil Erosion
Agricultural Productivity,
Drought Monitoring
Human Health
(mosquito-transmitted diseases
in wet areas)
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Courtesy of ESA
Introduction (2/3)
The need to monitor soil moisture on a global scale has motivated
the European Space Agency (ESA)'s Soil Moisture and Ocean
Salinity (SMOS) mission and the National Aeronautics and Space
Administration (NASA)'s Soil Moisture Active and Passive (SMAP)
mission.
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Courtesy of ESACourtesy of JPL
Introduction (3/3)
In this work,
We study the radar retrieval of soil moisture, as well as
canopy parameters, in a range of boreal forests.
The forward model is a discrete scatterer radar model.
The retrieval is formulated as an optimization problem.
The optimization algorithm is a global optimization scheme
known as simulated annealing.
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Outline
Forward Scattering Model for Forested Area
Inverse Model
Inversion of Model Parameters
Forested Area (Synthetic Data)
Forested Area (CanEx-SM10 Data)
Conclusion
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Outline
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Forward Scattering Model for Forested Area
Inverse Model
Inversion of Model Parameters
Forested Area (Synthetic Data)
Forested Area (CanEx-SM10 Data)
Conclusion
Forward Model: Introduction
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Soil & forest parameters
Scattering coefficients
Frequency, incidence angle
ForwardModel
;f(X p)X
p
Forward Model: Forest Geometry
Forest Geometry
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* S. L. Durden, J. J. van Zyl, and H. A. Zebker, "Modeling and observation of the radar polarizationsignature of forested areas," IEEE Trans. Geosci. Remote Sens., May 1989.
Forward Model: A general discrete scatterer radar model
by Durden et al.*
Forward Model: Scattering Mechanisms (1/2)
Canopy Layer
Trunk Layer
Ground
bg
bg
tgThe model identifies
4 distinct scattering
mechanisms:
b: branch
bg: branch-ground
tg: trunk-ground
g: ground
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* S. L. Durden, J. J. van Zyl, and H. A. Zebker, "Modeling and observation of the radar polarizationsignature of forested areas," IEEE Trans. Geosci. Remote Sens., May 1989.
Forward Model: A general discrete scatterer radar model
by Durden et al.*
Forward Model: Scattering Mechanisms (2/2)
Forward Model: A general discrete scatterer radar model
by Durden et al.*
The total backscattered power, represented by the Stokes matrix, is the
sum of the powers from all contributing scatterers.
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* S. L. Durden, J. J. van Zyl, and H. A. Zebker, "Modeling and observation of the radar polarizationsignature of forested areas," IEEE Trans. Geosci. Remote Sens., May 1989.
𝑀𝑡𝑜𝑡 = 𝑀𝑏 +𝑇𝑏𝑇𝑡𝑀𝑏𝑔𝑇𝑡𝑇𝑏 +𝑇𝑏𝑇𝑡𝑀𝑡𝑔𝑇𝑡𝑇𝑏 + 𝑇𝑏𝑇𝑡𝑀𝑔𝑇𝑡𝑇𝑏
branchcontribution
branch-groundcontribution
trunk-groundcontribution
groundcontribution
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Forward Model: Parameters
The forest floor is modeled as a rough dielectric surface with a layer of
nearly vertical dielectric cylinders (representing tree trunks) on top of it.
• The soil dielectric constant is related to the soil moisture via the soil type*
Branches are represented by a layer of randomly oriented cylinders.
The forward model uses properties of
• large and small branches (dielectric constant, length, radius, density,