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On the Radiative Transfer Model for Soil Moisture across Space, Time and Hydro-Climates

Maheshwari Neelam, Binayak P. Mohanty
2020 Remote Sensing  
Our results indicate that the sensitivity of brightness temperature (V- or H-polarization) is determined by the upscaling method and heterogeneity observed in the physical variables.  ...  On the contrary, for anthropogenically-manipulated environments such as SMEX02 and SMAPVEX12, the sensitivity to variables is highly influenced by the distribution of land surface heterogeneity and upscaling  ...  Acknowledgments: We acknowledge the support of the Schlumberger Faculty for Future Fellowship and thank all the students, scientists, and volunteers who participated in the various soil moisture campaigns  ... 
doi:10.3390/rs12162645 fatcat:bhjfj4ghvfg2zgsen6stdhbjia

A Data Mining Approach for Sharpening Thermal Satellite Imagery over Land

Feng Gao, William Kustas, Martha Anderson
2012 Remote Sensing  
A comparison of sharpening techniques applied over a rainfed agricultural area in central Iowa, an irrigated agricultural region in the Texas High Plains, and a heterogeneous naturally vegetated landscape  ...  The DMS approach builds regression trees between TIR band brightness temperatures and shortwave spectral reflectances based on intrinsic sample characteristics.  ...  Special thanks to Christopher Neale and Nurit Agam for providing airborne thermal imagery used in this study.  ... 
doi:10.3390/rs4113287 fatcat:dm5pv2lb2bbfpkphkt5hk652qa

A proposed extension to the soil moisture and ocean salinity level 2 algorithm for mixed forest and moderate vegetation pixels

Rocco Panciera, Jeffrey P. Walker, Jetse Kalma, Edward Kim
2011 Remote Sensing of Environment  
An extension to the SMOS approach is proposed that accounts for the heterogeneity of vegetation optical depth within the SMOS pixel.  ...  of the land surface heterogeneity over an area equivalent in size to a SMOS pixel.  ...  The authors wish to thank Phillip Maisongrande and Gilles Boulet at the Centre d'Etudes Spatiales de la BIOsphere (CESBIO) for the supervised classification of the Landsat 5 Thematic Mapper scene, and  ... 
doi:10.1016/j.rse.2011.07.017 fatcat:lb5qdrerljfb3fcxbbprufhf6a

GF-4 Satellite Fire Detection with a improved Contextual algorithm

Ning Zhang, Lin Sun, Zhen dong Sun
2021 IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing  
the high heterogeneity of pixels in a single spatial scene in the traditional method.  ...  In this study, the characteristics of brightness temperature difference between fire point area and non-fire point area are comprehensively analyzed.  ...  The timing algorithm also uses the absolute change of brightness temperature in sub-pixel as the judgment condition.  ... 
doi:10.1109/jstars.2021.3132360 fatcat:butordzwhrax5ng4zudxwx3vtm

A PCA–OLS Model for Assessing the Impact of Surface Biophysical Parameters on Land Surface Temperature Variations

Firozjaei, Alavipanah, Liu, Sedighi, Mijani, Kiavarz, Weng
2019 Remote Sensing  
The aim of this study is to propose an integrated model for characterizing LST spatiotemporal variations and for assessing the impact of surface biophysical parameters on the LST variations.  ...  The results of this study indicated the use of an integrated PCA–OLS model was effective for modeling of various environmental parameters and their relationship with LST.  ...  In addition, the authors deeply thank the Iran National Science Foundation (INSF) and International Relationship Program, University of Tehran for its great support in conducting this research.  ... 
doi:10.3390/rs11182094 fatcat:sfyv2pcfnba4ngud2wxxu3yhmi

An observing system simulation experiment for hydros radiometer-only soil moisture products

W.T. Crow, S.T.K. Chan, D. Entekhabi, P.R. Houser, A.Y. Hsu, T.J. Jackson, E.G. Njoku, P.E. O'Neill, Jiancheng Shi, Xiwu Zhan
2005 IEEE Transactions on Geoscience and Remote Sensing  
For large ( 3 kg m 2 ), a distinct positive bias, attributable to the impact of sub-footprint-scale landcover heterogeneity, is identified in soil moisture retrievals.  ...  Based on 1-km land surface model geophysical predictions within the United States Southern Great Plains (Red-Arkansas River basin), an observing system simulation experiment (OSSE) is carried out to assess  ...  The covariance term represents the impact of sub-footprint-scale correlation between static land surface characteristics and the observed brightness temperature.  ... 
doi:10.1109/tgrs.2005.845645 fatcat:7btwvktlzzaonpizoxr3ef2w4y

Required sampling-density of ground-based soil moisture and brightness temperature observations for calibration/validation of L-band satellite observations based on a virtual reality

Shaoning Lv, Bernd Schalge, Pablo Saavedra Garfias, Clemens Simmer
2019 Hydrology and Earth System Sciences Discussions  
required for soil moisture and brightness temperature validation.  ...  At the minimum sampling resolution for a 70 % confidence level also the accuracy of footprint-averaged brightness temperature estimates is equal or better than 15 K/10 K for H/V polarization  ...  Furthermore, we thank Prabhakar Shresta and Mauro Sulis from the Transregional Collaborative Research Center 32 (TR32) for their preliminary work and introduction to the TerrSysMP modeling platform.  ... 
doi:10.5194/hess-2019-192 fatcat:fynq6mpufjhvrbczi7jppsa5f4

Enhanced sharpening procedures on edge difference and water stress index basis over heterogeneous landscape of sub-humid region

Martin I. Bayala, Raúl E. Rivas
2014 Egyptian Journal of Remote Sensing and Space Sciences  
Results suggest that the T s * DL technique is the most adequate for simulating LST to high spatial resolution over the heterogeneous landscape of a sub-humid region, showing an average root mean square  ...  Energy Balance Station data and in situ measurements were used to validate the enhanced LST images over a mixed agricultural landscape in the sub-humid Pampean Region of Argentina (PRA), during -2010 and  ...  Acknowledgements This article was financed by the National Commission of Space Activities (CONAE), Commission of Scientific Research of Buenos Aires Province (CIC), Ministry of Science, Technology and  ... 
doi:10.1016/j.ejrs.2014.05.002 fatcat:jtipjc2vibdyzoulu4e2rdsvem

Evaluation of terrain effect on microwave radiometer measurement and its correction

Ying Guo, Jiancheng Shi, Jinyang Du, Xiuli Fu
2011 International Journal of Remote Sensing  
It is found that the variations of the local incidence and PR at the sub-pixel scales within the satellite footprints can have a significant terrain effect on the measured brightness temperatures.  ...  For example, Talone et al. (2007) performed a series of brightness temperature simulations and analysed the local incidence angle, shadowing and atmosphere effects on brightness temperatures at the L-band  ... 
doi:10.1080/01431161.2011.591844 fatcat:aufbolqndnfz5fm2ybe6rxgduy

The NAFE'06 data set: Towards soil moisture retrieval at intermediate resolution

Olivier Merlin, Jeffrey P. Walker, Jetse D. Kalma, Edward J. Kim, Jorg Hacker, Rocco Panciera, Rodger Young, Gregory Summerell, John Hornbuckle, Mohsin Hafeez, Thomas Jackson
2008 Advances in Water Resources  
Airborne L-band brightness temperature was mapped at 1 km resolution 11 times (every 1-3 days) over a 40 by 55 km area in the Yanco region and 3 times over a 40 by 50 km area that includes Kyeamba Creek  ...  One objective of NAFE'06 was to explore the suitability of the area for SMOS (Soil Moisture and Ocean Salinity) calibration/validation and develop downscaling and assimilation techniques for when SMOS  ...  Likewise the landholders of the Livingstone Creek and Yenda site are acknowledged for access to their properties.  ... 
doi:10.1016/j.advwatres.2008.01.018 fatcat:wcqkfky37rex5p6l7clncairqe

Assessing drought probability for agricultural areas in Africa with coarse resolution remote sensing imagery

O. Rojas, A. Vrieling, F. Rembold
2011 Remote Sensing of Environment  
A phenological model based on NDVI was employed for defining the start of season (SOS) and end of the grain filling stage (GFS) dates.  ...  Second, the per-pixel average VHI was aggregated for agricultural areas at sub-national level in order to obtain a drought intensity indicator.  ...  Acknowledgements The authors would like to thank Javier Gallego (JRC), Rene Gommes (FAO), Olivier Leo (JRC) and Simon Kay (JRC) for the useful suggestions and comments.  ... 
doi:10.1016/j.rse.2010.09.006 fatcat:npteimkcenfg3pwqbjpyni4vnu

A sub-pixel-based calculation of fire radiative power from MODIS observations: 1

David Peterson, Jun Wang, Charles Ichoku, Edward Hyer, Vincent Ambrosia
2013 Remote Sensing of Environment  
The methodology stems from the heritage of earlier bi-spectral retrievals of sub-pixel fire area and temperature.  ...  As a result, this study, the first in a two-part series, develops a new sub-pixel-based calculation of fire radiative power (FRP f ) for fire pixels detected at 1 km 2 nominal spatial resolution by the  ...  Bob Oglesby at the University of Nebraska -Lincoln and Dr. Wilfrid Schroeder at the University of Maryland -College Park for their constructive comments.  ... 
doi:10.1016/j.rse.2012.10.036 fatcat:dtafw7nqdrbypokpaknqphfhwq

Adaptive Estimation of Crop Water Stress in Nectarine and Peach Orchards Using High-Resolution Imagery from an Unmanned Aerial Vehicle (UAV)

Suyoung Park, Dongryeol Ryu, Sigfredo Fuentes, Hoam Chung, Esther Hernández-Montes, Mark O'Connell
2017 Remote Sensing  
The study site was classified into sub-regions based on crop properties, such as cultivars and tree training systems.  ...  In addition to the delineation of canopy pixels, the determination of T wet and T dry for CWSI has a critical influence on the accuracy of CWSI values as an indicator of crop water stress.  ...  Conflicts of Interest: The authors declare no conflict of interest. Remote Sens. 2017, 9, 828  ... 
doi:10.3390/rs9080828 fatcat:x3c23wqfnjfddec24w674eg5vy

A vegetation index based technique for spatial sharpening of thermal imagery

Nurit Agam, William P. Kustas, Martha C. Anderson, Fuqin Li, Christopher M.U. Neale
2007 Remote Sensing of Environment  
These results demonstrate the potential for improving the spatial resolution of thermal-band satellite imagery over this type of rainfed agricultural region.  ...  This algorithm is based on the assumption that a unique relationship between radiometric surface temperature (T R ) relationship and vegetation index (VI) exists at multiple resolutions.  ...  In practice, only a subset of points showing low sub-pixel heterogeneity in NDVI would be used to develop the regression equations, serving to filter out many of the outliers apparent in these distributions  ... 
doi:10.1016/j.rse.2006.10.006 fatcat:kg5cwyomlncojhrrs5yc6csk6u

Downscaling Meteosat Land Surface Temperature over a Heterogeneous Landscape Using a Data Assimilation Approach

Rihab Mechri, Catherine Ottlé, Olivier Pannekoucke, Abdelaziz Kallel, Fabienne Maignan, Dominique Courault, Isabel Trigo
2016 Remote Sensing  
However, with LSR observations being a mixture of the different sub-pixel temperatures present within the pixel, different combinations of sub-pixel temperatures could be solutions of the downscaling problem  ...  The simulation of different sub-pixel temperatures in the SETHYS model is possible by varying some parameter values (the greatest influence on SETHYS surface temperature estimation) with respect to their  ...  The observations y q and the state x q are related thanks to a nonlinear observational operator H as follows: where ε 0 q represents an observation error modeled as a random-centered Gaussian vector of  ... 
doi:10.3390/rs8070586 fatcat:gmssyo2nirfk3j4vdvhvitvzfe
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