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An Enhanced TIMESAT Algorithm for Estimating Vegetation Phenology Metrics From MODIS Data

B Tan, J T Morisette, R E Wolfe, F Gao, G A Ederer, J Nightingale, J A Pedelty
2011 IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing  
Our results show that for MODIS data in middle to high latitude regions, snow and land surface temperature information is critical in retrieving phenology metrics from satellite observations.  ...  MODIS VI data were pre-processed using snow-cover and land surface temperature data, and temporally smoothed with the enhanced TIMESAT algorithm.  ...  Feedback from a number of NACP investigators has also been valuable in refining the algorithm. Dr. Jonsson and Dr.  ... 
doi:10.1109/jstars.2010.2075916 fatcat:sulbxsobnjafhhxbzsddzde5ee

Estimation of seasonal dynamics of understory NDVI in northern forests using MODIS BRDF data: Semi-empirical versus physically-based approach

Jan Pisek, Miina Rautiainen, Maris Nikopensius, Kairi Raabe
2015 Remote Sensing of Environment  
In this short communication paper, we retrieved the seasonal courses of understory Normalized Difference Vegetation Index (NDVI) from MODIS BRDF data using the semi-empirical and physically-based approach  ...  Our results indicated both semi-empirical and physically-based approaches using MODIS BRDF data do have a potential to track seasonal changes in understory NDVI.  ...  The authors thank Titta Majasalmi, Anu Akujärvi, and Matti Mõttus for participation in field data collection.  ... 
doi:10.1016/j.rse.2015.03.003 fatcat:t4yq5slwkzcdtk4npqlgipt3ge

Combining Process Modelling and LAI Observations to Diagnose Winter Wheat Nitrogen Status and Forecast Yield

Andrew Revill, Vasileios Myrgiotis, Anna Florence, Stephen Hoad, Robert Rees, Alasdair MacArthur, Mathew Williams
2021 Agronomy  
Leaf N was accurately retrieved by the model (NRMSE = 6%).  ...  The model, which includes a leaf N-dilution function, was calibrated across N treatments based on LAI observations, and tested at validation plots.  ...  parameters based on observations.  ... 
doi:10.3390/agronomy11020314 fatcat:irhmv7dtxvagvc7shs27vk27bi

Evaluation and Exploitation of Retrieval Algorithms for Estimating Biophysical Crop Variables Using Sentinel-2, Venus, and PRISMA Satellite Data

Raffaele CASA,Deepak UPRETI,Angelo PALOMBO,Simone PASCUCCI,Hao YANG,Guijun YANG,Wenjiang HUANG,Stefano PIGNATTI
2020 Journal of Geodesy and Geoinformation Science  
useful for an accurate retrieving of crop biophysical parameters.  ...  Results of Sentinel-2 and Venus data for durum wheat-growing season were consistent with ground truth data and confirm also that SWIR bands, which are used as tie-points in the PROSAIL inversion, are extremely  ...  order to retrieve leaf biochemical parameters from Sentinel ̄2 and PRISMA satellite dataꎬ a math ̄ ematical inversion of the PROSAIL physically ̄based canopy RTM has been implemented in IDL.  ... 
doi:10.11947/j.jggs.2020.0408 doaj:b5d502c0199c48fb8542a609a060ff99 fatcat:z6xbztv35zcyfgjlpmjeh4vwom

Satellite Data-Based Phenological Evaluation of the Nationwide Reforestation of South Korea

Su-Jong Jeong, Chang-Hoi Ho, Sung-Deuk Choi, Jinwon Kim, Eun-Ju Lee, Hyeon-Ju Gim, Gil Bohrer
2013 PLoS ONE  
The retrieved nationwide growing season data were used to compare the spatial variations in forest biomass carbon density with the time-averaged growing season length for 61 forests.  ...  This study investigated nationwide variations in vegetation phenology using satellite-based growing season estimates for 1982-2008.  ...  Based on three satellite-retrieved surface phenology parameters, nationwide variations in phenology were evaluated.  ... 
doi:10.1371/journal.pone.0058900 pmid:23520541 pmcid:PMC3592835 fatcat:nbws6z7gg5ajdalgt46kq4d3qi

Soil Moisture Content Retrieval from Remote Sensing Data by Artificial Neural Network Based on Sample Optimization

Qixin Liu, Xingfa Gu, Xinran Chen, Faisal Mumtaz, Yan Liu, Chunmei Wang, Tao Yu, Yin Zhang, Dakang Wang, Yulin Zhan
2022 Sensors  
Soil moisture content (SMC) plays an essential role in geoscience research. The SMC can be retrieved using an artificial neural network (ANN) based on remote sensing data.  ...  With this method, data typically excluded in conventional approaches can be adequately employed.  ...  In Section 3, the methodology of the SSE is described, the array of input parameters is specified, and the entire ANN-based SMC retrieval process is demonstrated.  ... 
doi:10.3390/s22041611 pmid:35214511 pmcid:PMC8879226 fatcat:cqwljvbn4rfcbirynjstw6vgpm

Vegetation Optical Depth and Soil Moisture Retrieved from L-Band Radiometry over the Growth Cycle of a Winter Wheat

Thomas Meyer, Lutz Weihermüller, Harry Vereecken, François Jonard
2018 Remote Sensing  
The retrievals were significantly improved compared to in situ measurements by using the time, polarization, and angle dependent τ as a priori information.  ...  between τ over the entire growing season and the VWC as well as between τ and LAI.  ...  In the current Level 3 SMAP algorithm (SMAP SCA), Equation (6) is used to estimate the τ parameter based on information from ancillary data of VWC extracted from MODIS NDVI data and b parameter values  ... 
doi:10.3390/rs10101637 fatcat:cgo5uynlmfguplspb6aniic4ne

Pan-boreal mapping of forest growing stock volume using hyper-temporal Envisat ASAR ScanSAR backscatter data

Maurizio Santoro, Christiane Schmullius, Carsten Pathe, Julian Schwilk
2012 2012 IEEE International Geoscience and Remote Sensing Symposium  
Retrieval of forest growing stock volume (GSV) has been shown to be feasible with C-band backscatter data using hyper-temporal stacks.  ...  In this paper, we report on the generation of pan-boreal estimates of forest GSV representative for the year 2010 using Envisat ASAR ScanSAR backscatter measurements.  ...  data to the retrieval.  ... 
doi:10.1109/igarss.2012.6352000 dblp:conf/igarss/SantoroSPS12 fatcat:lsq2rv67djgtrcnv2s2fkw2hlm

Better revisiting chlorophyll content retrieval with varying senescent material and solar-induced chlorophyll fluorescence simulation on paddy rice during the entire growth stages

Nan Shan, Lei Xi, Qian Zhang, Naifeng Lin, Delin Xu, Bingshuai Cao
2021 Ecological Indicators  
In this study, growing season canopy hyperspectral reflectance between 400 nm and 900 nm was used to retrieve chlorophyll content (Cab) and leaf inclination (LIDFa) using radiative transfer models (RTMs  ...  The results showed that the accuracy of Cab retrieval was improved when the variation in senescent material (Cs) was considered, especially in the later growth stages.  ...  The authors are thankful to Christiaan van der Tol for providing the SCOPE model and Yongguang Zhang for providing the experiment data.  ... 
doi:10.1016/j.ecolind.2021.108057 fatcat:mfjmmzkxw5cldpcxi6kzdvr2by

Joint leaf chlorophyll content and leaf area index retrieval from Landsat data using a regularized model inversion system (REGFLEC)

Rasmus Houborg, Matthew McCabe, Alessandro Cescatti, Feng Gao, Mitchell Schull, Anatoly Gitelson
2015 Remote Sensing of Environment  
Validation results, based upon in-situ LAI and Chl l observations collected over maize and soybean fields in central Nebraska for the period 2001-2005, demonstrate Chl l retrieval with a relative root-mean-square-deviation  ...  In this current analysis, REGFLEC is applied to a time-series of Landsat data.  ...  We appreciate the data provided by the Center for Advanced Land Management Information Technologies (CALMIT) and the Carbon Sequestration Program, University of Nebraska-Lincoln.  ... 
doi:10.1016/j.rse.2014.12.008 fatcat:diat2wfstrcvrctbo54dxrfuji

Estimation of vegetation photosynthetic capacity from space-based measurements of chlorophyll fluorescence for terrestrial biosphere models

Yongguang Zhang, Luis Guanter, Joseph A. Berry, Joanna Joiner, Christiaan van der Tol, Alfredo Huete, Anatoly Gitelson, Maximilian Voigt, Philipp Köhler
2014 Global Change Biology  
We evaluate our V cmax estimation method at six agricultural flux tower sites in the midwestern US using spaced-based SIF retrievals.  ...  Abstract Photosynthesis simulations by terrestrial biosphere models are usually based on the Farquhar's model, in which the maximum rate of carboxylation (V cmax ) is a key control parameter of photosynthetic  ...  We acknowledge Eumetsat for the GOME-2 data. MODIS MOD13 EVI/NDVI data were obtained from the MODIS LP DAAC archive and MERIS-MTCI from the Infoterra Ltd server.  ... 
doi:10.1111/gcb.12664 pmid:24953485 fatcat:leqnhgnmk5awnojoeh3ogegb7y

Trajectory-Based Video Retrieval Using Dirichlet Process Mixture Models

X. Li, W. Hu, Z. Zhang, X. Zhang, G. Luo
2008 Procedings of the British Machine Vision Conference 2008  
In this paper, we present a trajectory-based video retrieval framework using Dirichlet process mixture models.  ...  and is able to deliver higher retrieval accuracy than the peer methods in the literature. (4) The framework has a nice scalability and adaptability in the sense that when new cluster data are presented  ...  In general, there are two types of motion-based video retrieval techniques: camera-based and object-based.  ... 
doi:10.5244/c.22.106 dblp:conf/bmvc/LiHZZL08 fatcat:ksbviopp6fflxp4wgg4yfe3fpe

Analyzing Daily Estimation of Forest Gross Primary Production Based on Harmonized Landsat-8 and Sentinel-2 Product Using SCOPE Process-Based Model

Rahul Raj, Bagher Bayat, Petr Lukeš, Ladislav Šigut, Lucie Homolová
2020 Remote Sensing  
In this study, we aimed to explore the potential and investigate the information content of the HLS data set using the Soil Canopy Observation of Photosynthesis and Energy fluxes (SCOPE) model to retrieve  ...  the temporal variations in vegetation properties, followed by the GPP simulations during the 2016 growing season of an evergreen Norway spruce dominated forest stand.  ...  Parameter Symbol We evaluated the quality of HLS data before the retrieval of vegetation properties. For the 2016 vegetation growing season, we downloaded HLS data for 39 days.  ... 
doi:10.3390/rs12223773 fatcat:crqmxko3ovh6xiwt3edtsgm7za

Extracting Agronomic Information from SMOS Vegetation Optical Depth in the US Corn Belt Using a Nonlinear Hierarchical Model

Colin Lewis-Beck, Victoria A. Walker, Jarad Niemi, Petruţa Caragea, Brian K. Hornbuckle
2020 Remote Sensing  
Remote sensing observations that vary in response to plant growth and senescence can be used to monitor crop development within and across growing seasons.  ...  which is based upon visual observations from roadways.  ...  In Section 3, we compare estimated parameters from our model across growing seasons and validate against estimates from USDA survey data.  ... 
doi:10.3390/rs12050827 fatcat:i6y726pfpvgttpxvjlrcqqlm34

Estimating Gravimetric Water Content of a Winter Wheat Field from L-Band Vegetation Optical Depth

Thomas Meyer, Thomas Jagdhuber, María Piles, Anita Fink, Jennifer Grant, Harry Vereecken, François Jonard
2019 Remote Sensing  
This δ-parameter is shown to have a distinct impact on the thermal emission at L-band, but keeping δ constant during the growth cycle of the winter wheat appeared to be valid for these mg retrievals.  ...  In addition, we performed a sensitivity analysis on the vegetation volume fraction (δ), an input parameter to the proposed approach which represents the volume percentage of solid plant material in air  ...  We are also grateful to MIT for supporting this research with the MIT-Germany Seed Fund "Global Water Cycle and Environmental Monitoring using Active and Passive Satellite-based Microwave Instruments"  ... 
doi:10.3390/rs11202353 fatcat:dcsqvr7zcvfxjliuyn3uuwjhqq
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