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Microwave Vegetation Index from Multi-Angular Observations and Its Application in Vegetation Properties Retrieval: Theoretical Modelling

Somayeh Talebiesfandarani, Tianjie Zhao, Jiancheng Shi, Paolo Ferrazzoli, Jean-Pierre Wigneron, Mehdi Zamani, Peejush Pani
2019 Remote Sensing  
Validation with ground-based measurements proved this model is an efficient tool to describe the microwave emissions of corn and wheat.  ...  Monitoring global vegetation dynamics is of great importance for many environmental applications.  ...  We thank all the reviewers for their careful reading of the manuscript and their constructive remarks. Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/rs11060730 fatcat:yowkttemyncvdmauwabfs4wk2q

A simplified land data assimilation scheme and its application to soil moisture experiments in 2002 (SMEX02)

Mahadevan Pathmathevan, Toshio Koike, Xin Li, Hideyuki Fujii
2003 Water Resources Research  
This paper investigates a method of retrieving a one-dimensional soil moisture profile and the surface and canopy temperature, under the influence of different vegetations and dynamics, by integrating  ...  The ground-based microwave radiometer (GBMR) measurements, gathered over the soil moisture experiments in 2002 (SMEX02) in Iowa, were assimilated into the LSS via a radiative transfer model (RTM) using  ...  The basis of geophysical model data assimilation is a four-dimensional representation of a unified, dynamically evolving geophysical system by a math-ematical model that has the capacity to predict dynamical  ... 
doi:10.1029/2003wr002124 fatcat:5tngfguoxncxpn7faidk4542rq

Simulating the influence of temperature on microwave transmissivity of trees during winter observed by spaceborne microwave radiometery

Qinghuan Li, Richard Kelly, Juha Lemmetyinen, Jinmei Pan
2020 IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing  
emission penetrating through the forest canopy, it also controls the forest thermal emission.  ...  Forest transmissivity is a key parameter for understanding spaceborne and airborne observations of the Earth's land surface because not only does it influences the proportion of sub-canopy upwelling microwave  ...  In ↑ , the tree thermal emission (1 − − ) and the ground emission penetrated through the tree canopy are the two major elements.  ... 
doi:10.1109/jstars.2020.3017618 fatcat:5t7vxcintzfypad4vzettxnvme

Using Passive Microwave Remote Sensing Techniques in Mapping Soil Moisture on a Regional Scale

Anna Ołdak, Thomas J. Jackson
2002 Miscellanea Geographica: Regional Studies on Development  
These two parameters determine the optical depth of the canopy, which is in turn responsible for vegetation layer transmissivity, attenuating the microwave signal from the soil surface.  ...  Increasing roughness results in an increase in the emissivity over that of a smooth surface. Surface roughness, vegetation water content and canopy parameter are associated with land cover types.  ... 
doi:10.2478/mgrsd-2002-0033 fatcat:psouzgnmibfbhabzrt7n6v74ry

Calibration of the L-MEB Model Over a Coniferous and a Deciduous Forest

J.P. Grant, K. Saleh-Contell, J.-P. Wigneron, M. Guglielmetti, Y.H. Kerr, M. Schwank, N. Skou, A.A. Van de Griend
2008 IEEE Transactions on Geoscience and Remote Sensing  
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  ...  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.  ...  and soil water dynamics in a forest stand."  ... 
doi:10.1109/tgrs.2007.914801 fatcat:i3eqf7tqhbhl3of2fkmlmsr6oi

Radar Remote Sensing of Agricultural Canopies: A Review

Susan C. Steele-Dunne, Heather McNairn, Alejandro Monsivais-Huertero, Jasmeet Judge, Pang-Wei Liu, Kostas Papathanassiou
2017 IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing  
The RT models (e.g. 440 Michigan Microwave Canopy Scattering (MIMICS), [143] and the Tor-Vergata Model [148]) are 441 energy-based equations that govern the transmission of energy through the scattering  ...  and emission.  ... 
doi:10.1109/jstars.2016.2639043 fatcat:6w5qd3dg2jd7ncdod7nn2un7gi

Remote Sensing Research in Hydrometeorology

William P. Kustas, Andrew N. French, Jerry L. Hatfield, Tom J. Jackson, M. Susan Moran, Al Rango, Jerry C. Ritchie, Tom J. Schmugge
2003 Photogrammetric Engineering and Remote Sensing  
For the hydrometeorological fluxes, including plant water stress, models estimating evapotranspiration have been developed using land surface temperature as a key boundary condition with recent schemes  ...  In addition, the development of the Thermal Kinetic Window and Crop Specific Temperatures have revealed the dynamic interactions among foliage temperature, plant species, and the physical environment.  ...  the snow layer, resulting in a microwave emission at the top of the snow surface being less than the ground emission.  ... 
doi:10.14358/pers.69.6.631 fatcat:aib65ol7wzd65kx3dntvzxbq74

Comparison of two microwave radiobrightness models and validation with field measurements

W.L. Crosson, C.A. Laymon, R. Inguva, C. Bowman
2002 IEEE Transactions on Geoscience and Remote Sensing  
This paper compares microwave brightness temperature (T B ) estimated by two radiobrightness models--a multi-layer coherent radiative transfer (CRT) model and a single-layer Fresnel reflectance model.  ...  However, for uniform profiles, differences in T B estimated by the radiobrightness models for a given permittivity value were less than 2 K.  ...  After an extensive review of research on the effects of vegetation on microwave energy transmission, Jackson and Schmugge [19] proposed a simple model in which the transmissivity of the vegetation layer  ... 
doi:10.1109/36.981356 fatcat:krdqwc2mvjcytlwwblvzm4ttvm

Soil moisture retrieval using the passive/active l- and s-band radar/radiometer

J.D. Bolten, V. Lakshmi, E.G. Njoku
2003 IEEE Transactions on Geoscience and Remote Sensing  
In addition, a radiative transfer model and two radar backscatter models are used to simulate the PALS observations.  ...  An integration of observations, regression retrievals and forward modeling is used to derive the best estimates of soil moisture under varying surface conditions.  ...  The approach was based on a model of microwave emission from a layered soil-vegetationatmosphere medium for frequencies in the range 1-20 GHz [13] .  ... 
doi:10.1109/tgrs.2003.815401 fatcat:u36hpiwr65bmzezho5rkb2lzau

Global Monitoring of the Vegetation Dynamics from the Vegetation Optical Depth (VOD): A Review

Frédéric Frappart, Jean-Pierre Wigneron, Xiaojun Li, Xiangzhuo Liu, Amen Al-Yaari, Lei Fan, Mengjia Wang, Christophe Moisy, Erwan Le Masson, Zacharie Aoulad Lafkih, Clément Vallé, Bertrand Ygorra (+1 others)
2020 Remote Sensing  
canopy layer in the microwave domain and which can be derived from both passive and active microwave observations, is increasingly used for monitoring a wide range of ecological vegetation variables.  ...  In this review, the theoretical bases of VOD estimates for both the passive and active microwave domains are presented and the global long-term VOD products computed from various groups in the world are  ...  Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/rs12182915 fatcat:lwxygy43qffvnju4pqtuxm4vzq

A Physically Constrained Inversion for Super-resolved Passive Microwave Retrieval of Soil Moisture and Vegetation Water Content in L-band [article]

Ardeshir Ebtehaj
2018 arXiv   pre-print
Unlike the existing algorithms, the presented approach can account for slowly varying dynamics of the vegetation water content over croplands through a temporal smoothing-norm regularization.  ...  Remote sensing of soil moisture and vegetation water content from space often requires underdetermined inversion of a zeroth-order approximation of the forward radiative transfer equation in L-band---known  ...  The model has three components: (1) emission by the soil surface (1 − r p )γ p T s , (2) upward emission by the slanted column of vegetation with a finite thickness (1 − ω p )(1 − γ p )T c , and (3) canopy  ... 
arXiv:1806.03298v2 fatcat:otl5fnjaijc3bf6gctx4da6wfm

Remote sensing in hydrology

Thomas J. Schmugge, William P. Kustas, Jerry C. Ritchie, Thomas J. Jackson, Al Rango
2002 Advances in Water Resources  
Remote sensing provides a means of observing hydrological state variables over large areas.  ...  The ones which we will consider in this paper are land surface temperature from thermal infrared data, surface soil moisture from passive microwave data, snow cover using both visible and microwave data  ...  the snow layer, resulting in a microwave emission at the top of the snow surface being less than the ground emission.  ... 
doi:10.1016/s0309-1708(02)00065-9 fatcat:7trxsuclcneqzp3vukhi3unvda

Retrieving near-surface soil moisture from microwave radiometric observations: current status and future plans

J.-P Wigneron, J.-C Calvet, T Pellarin, A.A Van de Griend, M Berger, P Ferrazzoli
2003 Remote Sensing of Environment  
However, the effects of vegetation cover, soil temperature, snow cover, topography, and soil surface roughness also play a significant role in the microwave emission from the surface.  ...  Passive microwave remotely sensed data have great potential for providing estimates of soil moisture with good temporal repetition on a daily basis and on a regional scale ( f 10 km).  ...  Jackson (USDA, Maryland) for providing the soil moisture mapping figure, and to Gail Wagman for revising the English version of the manuscript.  ... 
doi:10.1016/s0034-4257(03)00051-8 fatcat:cxrpxmrkuneydkicudgkhcjxhm

Modelling the passive microwave signature from land surfaces: A review of recent results and application to the L-band SMOS & SMAP soil moisture retrieval algorithms

J.-P. Wigneron, T.J. Jackson, P. O'Neill, G. De Lannoy, P. de Rosnay, J.P. Walker, P. Ferrazzoli, V. Mironov, S. Bircher, J.P. Grant, M. Kurum, M. Schwank (+12 others)
2017 Remote Sensing of Environment  
It has relied too on the use of numerical, physical and semi-empirical models to simulate the microwave brightness temperature of natural scenes for a variety of scenarios in terms of system configurations  ...  The SMAP sensor, based on a large mesh reflector 6 m in diameter providing a conically scanning antenna beam with a surface incidence angle of 40°, was launched in January of 2015.  ...  Acknowledgements This research work was funded by CNES (Centre National d'Etudes Spatiales) through the Science TOSCA (Terre Océan Surfaces Continentales et Atmosphère) program.  ... 
doi:10.1016/j.rse.2017.01.024 fatcat:wnl73fnfeffmvfobwa3q4fos3m

Evaluation of the SMOS L-MEB passive microwave soil moisture retrieval algorithm

Rocco Panciera, Jeffrey P. Walker, Jetse D. Kalma, Edward J. Kim, Kauzar Saleh, Jean-Pierre Wigneron
2009 Remote Sensing of Environment  
L-^band Microwave Emission of the Biosphere model, L-^MEB, is 250 the core of the SMOS mission retrieval algorithm ('SMOS L2') and is 251 based on a widely recognized approach to land emission simulation  ...  A model for the microwave emission of vegetation-^covered fields. Journal of Geophysical Research, (11), 229−237. Njoku, E. G., & Entekhabi, D.(1996).  ... 
doi:10.1016/j.rse.2008.10.010 fatcat:dv2rx5mllvfknme5v7urdvv4ou
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