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Global long-term passive microwave satellite-based retrievals of vegetation optical depth

Yi Y. Liu, Richard A. M. de Jeu, Matthew F. McCabe, Jason P. Evans, Albert I. J. M. van Dijk
2011 Geophysical Research Letters  
Introduction [2] Vegetation dynamics play an important role in the hydrological, energy and carbon cycles, through influences of land cover change on hydrologic responses, interactions with climate and  ...  The VOD increases with vegetation density; over dense vegetation (e.g., tropical rainforest), the transmissivity gets close to zero and the microwave emissions are dominated by vegetation. [6] The VOD  ... 
doi:10.1029/2011gl048684 fatcat:xpmus7gzbrcatamp2xhvryuy4u

Land surface phenologies and seasonalities using cool earthlight in mid-latitude croplands

W G Alemu, G M Henebry
2013 Environmental Research Letters  
Vegetation optical depth (VOD), a microwave analog of a vegetation index, was modeled as a function of AGDD with the resulting fitted convex quadratic models yielding both high coefficients of determination  ...  These results showed the potential of AMSR-E in monitoring and modeling cropland dynamics.  ...  We gratefully acknowledge the thoughtful comments from two anonymous reviewers that increased the clarity of the presentation.  ... 
doi:10.1088/1748-9326/8/4/045002 fatcat:vgpbdkok4zcgflv7xyqahfxzuq

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.  ...  solution spaces that are characterized by the eigenspace of the model Hessian.  ...  06/01/2016. dynamic constraints of vegetation transmissivity at resolution 1 to 5 km.  ... 
arXiv:1806.03298v2 fatcat:otl5fnjaijc3bf6gctx4da6wfm

III. Measuring surface soil moisture using passive microwave remote sensing

Thomas J. Jackson
1993 Hydrological Processes  
vegetation, [ = transmissivity of the vegetation layer, 7, = physical temperature of the vegetation and T;o,, = physical temperature of the background.  ...  Single Scattering Albedo (~0) [=Transmissivity of Vegetation Count +(@,,,-1 )exp(h) T,=Temperature of Vegetation (°K) T.on™ }emperature of Soil (T,.  ... 
doi:10.1002/hyp.3360070205 fatcat:73dqitt73vbcrene75j3akhsre

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  
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 frozen winter conditions, our previous study has indicated that observed microwave transmissivity of trees is also strongly influenced by temperature.  ...  The ground measured radiometer data and ancillary data are provided by the FMI Arctic Research Centre, the GCOM-W1 AMSR2 level 1R Tb product is provided by JAXA, and MODIS MOD44b Version 6 Vegetation  ... 
doi:10.1109/jstars.2020.3017618 fatcat:5t7vxcintzfypad4vzettxnvme

Parameterization of the Land Parameter Retrieval Model for L-Band Observations Using the NAFE'05 Data Set

R.A.M. de Jeu, T.R.H. Holmes, R. Panciera, J.P. Walker
2009 IEEE Geoscience and Remote Sensing Letters  
However, care should be taken when using the proposed dynamic roughness model as it is based on a limited data set, and a more thorough evaluation is necessary to test the validity of this new approach  ...  It was found that model convergence could only be achieved with a temporally dynamic roughness. The roughness was parameterized according to incidence angle and soil moisture.  ...  While it excludes the complex parameterization of the vegetation, a dynamic roughness model had to be included.  ... 
doi:10.1109/lgrs.2009.2019607 fatcat:llsojunzbfbynneb7d73tnfqzy

A PRELIMINARY STUDY ON MECHANISM OF LAI INVERSION SATURATION

J. Zhao, J. Li, Q. Liu, L. Yang
2012 The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences  
In order to analyze the saturation phenomena in parameter inversion, we analyze the changing of canopy reflectance and backscattering with increasing of LAI through PROSAIL and MIMICS model respectively  ...  Many parameters, such as albedo, vegetation index and leaf area index (LAI) inversed from satellite images, often get saturated when the surface vegetation cover reaches a certain high level.  ...  Remote Sensing of Environment, 92(4), pp.447-464. [5] Gitelson, A. A., 2004. Wide dynamic range vegetation index for remote quantification of biophysical characteristics of vegetation.  ... 
doi:10.5194/isprsarchives-xxxix-b1-77-2012 fatcat:guzs242yvrfppntdzqo6ykbtiy

Mapping recharge from space: roadmap to meeting the grand challenge

Dara Entekhabi, Mahta Moghaddam
2006 Hydrogeology Journal  
The approaches rely on microwave remote sensing in order to measure land surface states in the presence of atmosphere and vegetation cover that attenuate and disturb the signal as it travels from the surface  ...  This hydrologic flux is intimately related to the distribution and functioning of vegetation cover and type. In turn, it also plays a significant role in the distribution of vegetation.  ...  To penetrate vegetation, soil surface, and deep soil, lower-frequency microwaves are needed due to their ability to travel through significant vegetation canopies and through soil with a low attenuation  ... 
doi:10.1007/s10040-006-0120-6 fatcat:ckl4twb3gvg5tfnftdaamlj6na

Soil moisture estimates from TRMM Microwave Imager observations over the Southern United States

Rajat Bindlish, Thomas J Jackson, Eric Wood, Huilin Gao, Patrick Starks, David Bosch, Venkat Lakshmi
2003 Remote Sensing of Environment  
The algorithm for deriving soil moisture and temperature from TMI observations is based on a physical model of microwave emission from a layered soil -vegetation -atmosphere medium.  ...  The most readily available observations from which a surface wetness state could be derived is the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) observations at 10.65 GHz.  ...  Acknowledgements This work is supported by NASA Earth Science Enterprise Modeling and Data Analysis Research Program.  ... 
doi:10.1016/s0034-4257(03)00052-x fatcat:qiefihdwg5bsle54vf6e5umsfu

Water resource monitoring systems and the role of satellite observations

A. I. J. M. van Dijk, L. J. Renzullo
2011 Hydrology and Earth System Sciences  
estimates of current (and past) water resources distribution.  ...  1 We define "operational" here as producing information on a regular basis, and "spatial water resources monitoring systems" (SWRMS) as software that integrates observations into models to produce spatial  ...  This work is part of the water information research and development alliance between the Bureau of Meteorology and CSIRO's Water for a Healthy Country Flagship.  ... 
doi:10.5194/hess-15-39-2011 fatcat:ism2x2mlefhqpjsw4yacwqm5pq

Water resource monitoring systems and the role of satellite observations

A. I. J. M. van Dijk, L. J. Renzullo
2010 Hydrology and Earth System Sciences Discussions  
estimates of current (and past) water resources distribution.  ...  1 We define "operational" here as producing information on a regular basis, and "spatial water resources monitoring systems" (SWRMS) as software that integrates observations into models to produce spatial  ...  This work is part of the water information research and development alliance between the Bureau of Meteorology and CSIRO's Water for a Healthy Country Flagship.  ... 
doi:10.5194/hessd-7-6305-2010 fatcat:gpnaxsp5mnd7pout3dpso72xsm

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  
Monitoring global vegetation dynamics is of great importance for many environmental applications.  ...  Validation with ground-based measurements proved this model is an efficient tool to describe the microwave emissions of corn and wheat.  ...  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

SMOSREX: A long term field campaign experiment for soil moisture and land surface processes remote sensing

Patricia de Rosnay, Jean-Christophe Calvet, Yann Kerr, Jean-Pierre Wigneron, François Lemaître, Maria José Escorihuela, J. Muñoz Sabater, Kauzar Saleh, Joël Barrié, Gilles Bouhours, Laurent Coret, Guy Cherel (+9 others)
2006 Remote Sensing of Environment  
Soil freezing is shown to be drastically different for bare soil and vegetation covered plots, with a large threshold effect on microwave surface emission.  ...  Within the context of the preparation of SMOS activities over land, a field campaign, SMOSREX (Surface Monitoring Of the Soil Reservoir EXperiment), has been in operation since January 2001 in Mauzac,  ...  The vegetation transmissivity γ is a critical variable which characterizes the vegetation effect on the microwave emission of the surface.  ... 
doi:10.1016/j.rse.2006.02.021 fatcat:y3x22gqet5eyzi25cf7vzstn2e

Using a Discrete Scattering Model to Constrain Water Cloud Model for Simulating Ground-Based Scatterometer Measurements and Retrieving Soil Moisture

Xiaojing Bai, Donghai Zheng, Jun Wen, Xin Wang, R Van der Velde
2021 IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing  
transmissivity agree well with the seasonal vegetation dynamics; ii) the total scattering simulated by the TVG constrained WCMs shows a good consistency with the scatterometer measurements, and the simulated  ...  It is found that: i) the calibrated Tor Vergata (hereafter "TVG") model simulates well the seasonal dynamics and magnitudes of scatterometer measurements, and the simulated scattering components and vegetation  ...  For simulating the microwave backscatter from vegetation covered soil surfaces, soil scattering models are often coupled to vegetation scattering models.  ... 
doi:10.1109/jstars.2021.3111606 fatcat:v5d7wspivrholoqstselihrkba

Front Matter: Volume 9260

Thomas J. Jackson, Jing Ming Chen, Peng Gong, Shunlin Liang
2014 Land Surface Remote Sensing II  
SPIEDigitalLibrary.org Paper Numbering: Proceedings of SPIE follow an e-First publication model, with papers published first online and then in print.  ...  Utilization of CIDs allows articles to be fully citable as soon as they are published online, and connects the same identifier to all online, print, and electronic versions of the publication.  ...  0P Comparison between microwave coherent and incoherent scattering models for wetland vegetation in Poyang Lake area [9260-25] 9260 0Q Simulation of microwave brightness temperature over heterogeneous  ... 
doi:10.1117/12.2179079 fatcat:obc4dx7fr5egve4apiuzi7nxlm
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