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Data-Driven Interpolation of Sea Level Anomalies Using Analog Data Assimilation

Redouane Lguensat, Phi Huynh Viet, Miao Sun, Ge Chen, Tian Fenglin, Bertrand Chapron, Ronan Fablet
2019 Remote Sensing  
of the reconstruction of higher-resolution Sea Level Anomaly (SLA) fields using analog strategies.  ...  This reconstruction is stated as an analog data assimilation issue, where the analog models rely on patch-based and Empirical Orthogonal Functions (EOF)-based representations to circumvent the curse of  ...  A popular data assimilation algorithm that is largely used in the literature to grid sea level anomalies from along-track data is called Optimal Interpolation (OI) (e.g., [15, 33] ), this algorithm is  ... 
doi:10.3390/rs11070858 fatcat:2w4qap5c3zhzdkofqmuo2v4fbm

Sea surface temperature prediction and reconstruction using patch-level neural network representations [article]

Said Ouala, Cedric Herzet, Ronan Fablet
2018 arXiv   pre-print
Our numerical experiments demonstrate that the proposed patch-level neural-network-based representations outperform other data-driven models, including analog schemes, both in terms of forecasting and  ...  assimilation of geophysical fields from satellite-derived remote sensing data.  ...  One may cite both analog schemes [7] and neural networks [8] as relevant examples of efficient data-driven approaches for the forecasting and reconstruction of sea surface dynamics.  ... 
arXiv:1806.00144v1 fatcat:hc4iumya5fcdvfp2fcnhsjcshe

Sea Surface Dynamics Reconstruction Using Neural Networks Based Kalman Filter

Said Ouala, Ronan Fablet, Cedric Herzet, Lucas Drumetz, Bertrand Chapron, Ananda Pascual, Fabrice Collard, Lucile Gaultier
2019 IGARSS 2019 - 2019 IEEE International Geoscience and Remote Sensing Symposium  
From our numerical experiment, we prove the relevance of the proposed architecture in the reconstruction of geophysical fields with respect to the state-of-the-art schemes.  ...  In this work, we propose an alternative to the Ensemble Kalman filter through the implementation of a neural networks filtering scheme based on a parametric stochastic model.  ...  Analog methods are one of the first data-driven techniques to develop this data-driven paradigm within a data assimilation framework [5] .  ... 
doi:10.1109/igarss.2019.8898086 dblp:conf/igarss/OualaFHDCPCG19 fatcat:kbq6cwxcgfa3pa5vbl4nzpxngm

Analog Data Assimilation for Along-Track Nadir and Swot Altimetry Data in the Western Mediterranean Sea

M. Lopez-Radcenco, A. Pascual, L. Gomez-Navarro, A. Aissa-El-Bey, R. Fablet
2018 IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium  
In this work, we consider the application of AnDA to the spatio-temporal interpolation of SLA (Sea Level Anomalies) from two types of satellite altimetry data, namely from along-track nadir data [1] and  ...  The ever increasing availability of in situ, remote sensing and simulation data supports the development of data-driven alternatives to classical model-driven methods for the interpolation of sea surface  ...  ANALOG DATA ASSIMILATION FRAMEWORK The analog data assimilation [7] is a fully data-driven data assimilation framework for dynamical systems.  ... 
doi:10.1109/igarss.2018.8519089 dblp:conf/igarss/Lopez-RadcencoP18 fatcat:coayaov54vd5blbpu7i45mgrlu

Data-driven and learning-based interpolations of along-track Nadir and wide-swath SWOT altimetry observations

Maxime Beauchamp, ronan fablet, Clément Ubelmann, Maxime Ballarotta, Bertrand Chapron
2020 Proceedings of the 10th International Conference on Climate Informatics  
In Section III, we present the data-driven approaches used in the intercomparison: 1) AnDA, a purely data-driven data assimilation scheme combining a patch-based analog forecasting operator with Kalman-based  ...  AnDA The Analog Data Assimilation (AnDA) is a purely data-driven data assimilation method, that introduces a statistical operator A as a substitute for the dynamical model M, leading to the following state-space  ... 
doi:10.1145/3429309.3429313 fatcat:zrhtc5iajzcmhmcnjh4yswacqe

Neural Network Based Kalman Filters for the Spatio-Temporal Interpolation of Satellite-Derived Sea Surface Temperature

Said Ouala, Ronan Fablet, Cédric Herzet, Bertrand Chapron, Ananda Pascual, Fabrice Collard, Lucile Gaultier
2018 Remote Sensing  
Function (EOF) based interpolation and analog data assimilation).  ...  data assimilation.  ...  Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/rs10121864 fatcat:ytgmlxee5fejlerlhs3vb52iui

Spatio-temporal interpolation of altimeter-derived SSH fields using analog data assimilation: A case-study in the south china sea

Redouane Lguensat, Miao Sun, Ge Chen, Fenglin Tian, Ronan Fablet
2017 2017 IEEE International Geoscience and Remote Sensing Symposium (IGARSS)  
The analog data assimilation combines an ensemble Kalman model and a dataset of exemplars issued from high-resolution numerical simulations to perform an exemplar-based spatio-temporal interpolation of  ...  As a case-study, we consider a region in the South China Sea and demonstrate the proposition analog data assimilation outperforms the classical OI by about 20% in terms of mean square reconstruction error  ...  The main idea of this work consists in expressing a Sea Level Anomaly (SLA) map as a sum of two scale components, namely, large and fine scales.  ... 
doi:10.1109/igarss.2017.8127625 dblp:conf/igarss/LguensatSCTF17 fatcat:o3zsgqtocvddjbbfxi4kutaqjq

Spatio-Temporal Interpolation of Cloudy SST Fields Using Conditional Analog Data Assimilation

Ronan Fablet, Phi Viet, Redouane Lguensat, Pierre-Henri Horrein, Bertrand Chapron
2018 Remote Sensing  
We here demonstrate the relevance of the analog data assimilation (AnDA) for an application to the reconstruction of cloud-free level-4 gridded Sea Surface Temperature (SST).  ...  data and interpolation grid.  ...  Conflicts of Interest: The authors declare no conflicts of interest.  ... 
doi:10.3390/rs10020310 fatcat:zylrpczzg5evfdviugtvzgdpua

Ocean data assimilation: a case for ensemble optimal interpolation

P Oke, G Brassington, D Griffin, A Schiller
2010 Australian Meteorological and Oceanographic Journal  
Acknowledgments Financial support for this research is provided by CSIRO, the Bureau of Meteorology, and the Royal Australian Navy as part of the Bluelink project, and the US Office of Naval Research (  ...  Drifter data are provided by NOAA-AOML and SST observations are provided by NASA, NOAA and Remote Sensing Systems.  ...  This is because the ob-served sea-level anomaly typically represents the properties of the ocean interior in a way that is somewhat analogous to mean sea-level pressure representing the properties of the  ... 
doi:10.22499/2.5901.008 fatcat:4fcm2uz32vcv5l6qwuvgjeuweu

Sea Level Forecasts Aggregated from Established Operational Systems

Andy Taylor, Gary Brassington
2017 Journal of Marine Science and Engineering  
A system for providing routine seven-day forecasts of sea level observable at tide gauge locations is described and evaluated.  ...  The prospect of interpolation between observation sites and exploitation of lagged-ensemble uncertainty estimates could be meaningfully pursued.  ...  Acknowledgments: Thanks for input from Kevin Walsh at University of Melbourne, James Chittleborough at Bureau Tidal Unit.  ... 
doi:10.3390/jmse5030033 fatcat:xmqdt5ni3zahde45j6vchozw2y

The Bluelink ocean data assimilation system (BODAS)

Peter R. Oke, Gary B. Brassington, David A. Griffin, Andreas Schiller
2008 Ocean Modelling  
4-7 cm of observed coastal sea-level.  ...  BODAS is an ensemble optimal interpolation system that uses an ensemble of intraseasonal anomalies from a free running model to estimate the background error covariances (BECs).  ...  Coastal sea-level around Australia is provided by the National Tidal Centre and state authorities.  ... 
doi:10.1016/j.ocemod.2007.11.002 fatcat:wzi6zaan4fes7hi5nr4gs55gse

Eddy Resolving Global Ocean Prediction

Alan J. Wallcraft, E. Joseph Metzger, Ole Martin Smedstad
2009 2009 DoD High Performance Computing Modernization Program Users Group Conference  
maintaining the data needed, and completing and reviewing the collection of information Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions  ...  The public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and  ...  To the best of our knowledge and ability, it is complete, accurate, and up-to-date as of November 2, 2007. We also thank Charlene Parker for her assistance. This is contribution NRL/BC/7304-07-7170.  ... 
doi:10.1109/hpcmp-ugc.2009.42 fatcat:r4lkyanrxzfa3hrmouektpdvjy

Eddy-resolving global ocean prediction [chapter]

Harley E. Hurlburt, Eric P. Chassignet, James A. Cummings, A. Birol Kara, E. Joseph Metzger, Jay F. Shriver, Ole Martin Smedstad, Alan J. Wallcraft, Charlie N. Barron
2008 Ocean Modeling in an Eddying Regime  
maintaining the data needed, and completing and reviewing the collection of information Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions  ...  The public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and  ...  To the best of our knowledge and ability, it is complete, accurate, and up-to-date as of November 2, 2007. We also thank Charlene Parker for her assistance. This is contribution NRL/BC/7304-07-7170.  ... 
doi:10.1029/177gm21 fatcat:j45zq7adzffidmg4muatutgn4q

The value of sustained ocean observations for sea-ice predictions in the Barents Sea

Mitchell Bushuk, Xiaosong Yang, Michael Winton, Rym Msadek, Matthew Harrison, Anthony Rosati, Rich Gudgel
2019 Journal of Climate  
Analysis of the Barents Sea ocean heat budget suggests that ocean heat content anomalies in this region are driven by surface heat fluxes on seasonal time scales.  ...  In this work, we perform a hierarchy of observing system experiments with a coupled global data assimilation and prediction system to assess the value of different classes of oceanic and atmospheric observations  ...  CM2.1 uses 50 vertical ocean levels, with layer thicknesses of 10 m in the upper 230 m of the ocean.  ... 
doi:10.1175/jcli-d-19-0179.1 fatcat:tgnrdthuvzfq5fkaiwudlsyy5e

Accelerated sea ice loss in the Wandel Sea points to a change in the Arctic's Last Ice Area

Axel J. Schweiger, Michael Steele, Jinlun Zhang, G. W. K. Moore, Kristin L. Laidre
2021 Communications Earth & Environment  
Nevertheless, in August 2020 the area experienced record-low sea ice concentration. Here we use satellite data and sea ice model experiments to determine what caused this record sea ice minimum.  ...  AbstractThe Arctic Ocean's Wandel Sea is the easternmost sector of the Last Ice Area, where thick, old sea ice is expected to endure longer than elsewhere.  ...  Cohen for assistance with ocean hydrographic data analysis. We acknowledge the service of all the data providers.  ... 
doi:10.1038/s43247-021-00197-5 fatcat:b3hdlfmhurbe7pmfkxuabhjj54
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