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Improving the Intercalibration of $\sigma^{0}$ Values for the Jason-1 and Jason-2 Altimeters

G.D. Quartly
2009 IEEE Geoscience and Remote Sensing Letters  
For the Jason-1 and Jason-2 altimeters the derivation of σ 0 from the full waveform data is known to be sensitive to the recovered value for ψ 2 , a term encompassing both mispointing and inhomogeneities  ...  The six months of data from the Jason-1/2 tandem mission reveal that different σ 0 corrections are needed for these two causes of non-zero ψ 2 values.  ...  Jason-2 IGDR data were obtained from the CLS FTP server, under the OSTST-approved project 'TRIDENT II'.  ... 
doi:10.1109/lgrs.2009.2020921 fatcat:wsz4rwmoxjgxvjbhnjcsewva74

Improvements to estimating the air–sea gas transfer velocity by using dual-frequency, altimeter backscatter

Lonneke Goddijn-Murphy, David K. Woolf, Bertrand Chapron, Pierre Queffeulou
2013 Remote Sensing of Environment  
Recently C-band backscatter data were made available for altimeters on board the JASON-1 and JASON-2 satellites.  ...  Air-sea gas exchange is affected by sea surface roughness and a previous study shows a significant relation between Ku-band backscattering from satellite altimeters and field estimates of gas transfer  ...  We appreciate the use of DMS concentration and flux data from the  ... 
doi:10.1016/j.rse.2013.07.026 fatcat:7d5a2uupongxhdom2r4xbohwfi

Global Calibration and Error Estimation of Altimeter, Scatterometer, and Radiometer Wind Speed Using Triple Collocation

Agustinus Ribal, Ian R. Young
2020 Remote Sensing  
The six altimeters were TOPEX, ERS-2, JASON-1, ENVISAT, JASON-2, and CRYOSAT-2, whilst the three scatterometers were QUIKSCAT, METOP-A, and METOP-B and the four radiometers included SSMI-F15, AMSR-2, WINDSAT  ...  It was found that altimeters have the smallest error standard deviations for wind speed measurements followed by scatterometers and then radiometers.  ...  Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/rs12121997 fatcat:mzlut5cobjadvgpmefezb45oum

An Overview of Requirements, Procedures and Current Advances in the Calibration/Validation of Radar Altimeters

Graham D. Quartly, Ge Chen, Francesco Nencioli, Rosemary Morrow, Nicolas Picot
2021 Remote Sensing  
This special issue brings together 19 papers, with a focus on the recent missions (Jason-2, Jason-3, Sentinel-3A and HY-2B) as well as detailing the issues for anticipated future missions such as SWOT.  ...  This editorial provides a brief guide to the approaches and issues for cal/val of the various different derived parameters, including a synopsis of the papers in this special issue.  ...  Acknowledgments: We thank the assistant editor for her guidance through the editorial process, and we are also grateful to those who have stepped in to oversee the review process for papers that were written  ... 
doi:10.3390/rs13010125 fatcat:oxalyomb25frnavurtc7iuduyu

Uncertainty in Satellite estimate of Global Mean Sea Level changes, trend and acceleration

Michaël Ablain, Benoit Meyssignac, Lionel Zawadzki, Rémi Jugier, Aurélien Ribes, Anny Cazenave, Nicolas Picot
2019 Earth System Dynamics Discussions  
We analyse 25 years of satellite altimetry data and estimate for the first time the error variance-covariance matrix for the GMSL record with a time resolution of 10 days.  ...  (Ablain et al., 2015) estimated the uncertainty of the GMSL trend over the period 1993–2014 by thoroughly analyzing the error budget of the satellite altimeters and showed that it amounts to  ...  Acknowledgment This work was carried out as part of the Sea Level CCI (SL_cci) project (Climate Change Initiative program) supported by ESA and the SALP (Service d'Altimétrie et de Localisation Précise  ... 
doi:10.5194/essd-2019-10 fatcat:lcetwmbhofcyzde5xmy2y77gt4

Uncertainty in satellite estimates of global mean sea-level changes, trend and acceleration

Michaël Ablain, Benoît Meyssignac, Lionel Zawadzki, Rémi Jugier, Aurélien Ribes, Giorgio Spada, Jerôme Benveniste, Anny Cazenave, Nicolas Picot
2019 Earth System Science Data  
We analysed 25 years of satellite altimetry data and provided for the first time the error variance–covariance matrix for the GMSL record with a time resolution of 10 days.  ...  Previous authors have estimated the uncertainty in the GMSL trend over the period 1993–2014 by thoroughly analysing the error budget of the satellite altimeters and have shown that it amounts to <span  ...  We would like to thank all contributors of the Sea Level CCI (SL_cci) project (Climate Change Initiative programme) and of the SALP (Service d'Altimétrie et de Localisation Précise), with special recognition  ... 
doi:10.5194/essd-11-1189-2019 fatcat:dyii3hxnkjfnjbfqp6wjnccqja

Local sea level trends, accelerations and uncertainties over 1993–2019

Pierre Prandi, Benoit Meyssignac, Michaël Ablain, Giorgio Spada, Aurélien Ribes, Jérôme Benveniste
2021 Scientific Data  
For accelerations, uncertainties range from 0.057 to 0.12 mm.yr−1, with a mean value of 0.062. We also perform a sensitivity study to investigate a range of plausible error budgets.  ...  Over 1993–2019, we find that the average local sea level trend uncertainty is 0.83 mm.yr−1 with values ranging from 0.78 to 1.22 mm.yr−1.  ...  that the regional bias uncertainty is around ±10 mm for the TOPEX-B/Jason-1 transition and ±6 mm for the Jason-1/ Jason-2 and Jason-2/Jason-3 transitions (at the 1σ level).  ... 
doi:10.1038/s41597-020-00786-7 pmid:33414438 fatcat:c4uo4774djeu5adakx2xkpx4ti

Validation of AltiKa Matching Pursuit Rain Flag

J. Tournadre, J. C. Poisson, N. Steunou, B. Picard
2015 Marine Geodesy  
(C-band for Topex and Jason-1 and S-band for Envisat) by rain droplets, were defined and are currently used operationally (Tournadre and Morland, 1997; Tournadre, 2004; Tran et al., 2005; Quartly et al  ...  For cycles 2 to 9, the flag detects about 9% of 1Hz data, 5.5% as rainy and 3.5 % as backscatter bloom (or sigma0 bloom).  ...  The variable λ is the scale and t is the point where the wavelet is centered. For discrete time-series, CWT cannot be computed exactly, and discrete wavelet transform (DWT) has to be used.  ... 
doi:10.1080/01490419.2014.1001048 fatcat:lvpo354ws5bw7cjmwncouscqf4

Validation of Recent Altimeter Missions at Non-Dedicated Tide Gauge Stations in the Southeastern North Sea

Saskia Esselborn, Tilo Schöne, Julia Illigner, Robert Weiß, Thomas Artz, Xinge Huang
2022 Remote Sensing  
The precisions of sea-level measurements and regional biases for six altimeter missions (Jason-1/2/3, Envisat, Saral, Sentinel-3A) are assessed in this study at 11 GNSS-controlled tide gauge stations in  ...  The precision of the altimeters depends on the location and mission and ranges from 1.8 to 3.7 cm if the precision of the gauges is 2 cm.  ...  Absolute regional mission biases for each mission and number of contributing gauges for Jason-3 (J3), Jason-2 (J2), Jason-1 (J1), Sentinel-3A (S3A), Saral (Sa) and Envisat (Env  ... 
doi:10.3390/rs14010236 fatcat:4e3o3wg5rbdr3j4vdbksut6xra

STAR: Spatio-temporal altimeter waveform retracking using sparse representation and conditional random fields

Ribana Roscher, Bernd Uebbing, Jürgen Kusche
2017 Remote Sensing of Environment  
We apply STAR to data from the Jason-1, Jason-2 and Envisat missions for study sites in the Gulf of Trieste, Italy and in the coastal region of the Ganges-Brahmaputra-Meghna estuary, Bangladesh.  ...  Over open oceans, altimeter return waveforms generally correspond to the Brown model, and by inversion, estimated shape parameters provide mean surface height and wind speed.  ...  We also thank the associate editor and three anonymous reviewers for their constructive comments which helped us to significantly improve the manuscript.  ... 
doi:10.1016/j.rse.2017.07.024 fatcat:co3qdwyitrdi7p7wzrydekr4k4

Self- and Inter-Crossover Points of Jasons' Missions as New Essential Add-on of Satellite Altimetry in the Sub-Arctic Seas and the Southern Ocean

Sergei Badulin, Andrey Kostianoy, Pavel Shabanov, Vitali Sharmar, Vika Grigorieva, Sergey Lebedev
2021 Remote Sensing  
The time delay between two consecutive measurements in the high-latitude sites is less than 2 h for SC and 1 h for IC, thus providing a ground for monitoring large-scale currents (including current direction  ...  The Norwegian Sea case study illustrates the value of the special crossovers for the Sub-Polar seas and the feasibility of building the networks of SC and IC in other areas of the World Ocean.  ...  Table 1 presents meridional dependencies of variability of parameters measured by altimeter for the ICs with the fixed ascending track N165 of Jason-3 and Jason-2 tracks N40-62.  ... 
doi:10.3390/rs13040658 fatcat:eg6x6bdwmjehzbhb23xv4yk4ay

Ensuring that the Sentinel-3A altimeter provides climate-quality data

Graham Quartly, Francesco Nencioli, Sylvie Labroue, Pierre Femenias, Remko Scharroo, Saleh Abdalla, Pascal Bonnefond, Mathilde Cancet, Marie-laure Frery, Matthias Raynal, Steven Baker, Alan Muir (+10 others)
2017 Remote Sensing of the Ocean, Sea Ice, Coastal Waters, and Large Water Regions 2017  
Its suite of instruments for measuring surface topography includes a Microwave Radiometer (MWR) and SRAL, the first delay-Doppler instrument to provide global coverage.  ...  Further waveform analysis techniques are being developed to improve the retrieval of information over sea-ice, land-ice and inland waters.  ...  ), and a subsequent adjustment of σ 0 (normalized amplitude of return signal).  ... 
doi:10.1117/12.2277593 fatcat:mwdyslsa4vgj7ezbkodr4r5tqm

Validation of Envisat Rain Detection and Rain Rate Estimates by Comparing With TRMM Data

Ngan Tran, Jean Tournadre, Pierre Femenias
2008 IEEE Geoscience and Remote Sensing Letters  
This letter provides validation results on both Envisat altimeter rain detection flag and rain rate estimates.  ...  This assessment was performed based on 18-month collocated data sets between Envisat with two sensor measurements from the Tropical Rainfall Measuring Mission, i.e., the microwave imager and the precipitation  ...  ACKNOWLEDGMENT The authors would like to thank the Goddard Space Flight Center Distributed Active Archive Center for the straightforward and rapid access via ftp to the TRMM data.  ... 
doi:10.1109/lgrs.2008.2002043 fatcat:jmd7zqvgafdztmocas5f2zr2nu

Achieving Satellite Instrument Calibration for Climate Change

George Ohring, Joe Tansock, William Emery, James Butler, Lawrence Flynn, Fuzhong Weng, Karen St. Germain, Bruce Wielicki, Changyong Cao, Mitchell Goldberg, Jack Xiong, Gerald Fraser (+12 others)
2007 EOS  
Jerry Sullivan for his careful and detailed review of the manuscript. His comments were always on the mark. Marc Pulliam did an excellent job of graphics design and layout of the report.  ...  The manuscript contents are solely the opinions of the authors and do not constitute a statement of policy, decision, or position on behalf of NOAA or the U. S. Government.  ...  spatial sampling noise of the ocean data, about 0.4 Wm -2 (1σ).  ... 
doi:10.1029/2007eo110015 fatcat:n2nhhks3fbbklbxwrvso3eeqaq

Aquarius Wind Speed Products: Algorithms and Validation

Alexander G. Fore, Simon H. Yueh, Wenqing Tang, Akiko K. Hayashi, Gary S. E. Lagerloef
2014 IEEE Transactions on Geoscience and Remote Sensing  
We find the performance of the Aquarius scatterometer-only wind speed is better than 1.00 ms −1 , with best performance for low wind speeds and increasing noise levels as the wind speed increases.  ...  The CAP wind speed product is significantly better than the scatterometer-only due to the inclusion of passive measurements and achieves 0.70 ms −1 root-mean-square error.  ...  ACKNOWLEDGMENT This research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.  ... 
doi:10.1109/tgrs.2013.2267616 fatcat:gdxfssm2znevfj2lvluh6cz3fy
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