Hydrographic observations acquired over five surveys, each of about 6 days' duration, were assimilated into a QG open boundary ocean model. Optimal Interpolation We now describe the OI method. Optimal Interpolation Optimal Interpolation or OI is a commonly used and fairly simple but powerful method of data assimilation. [1992, 1995], Burgers et al. The mix of subsystems now planned includes The optimal interpolation is a sequential data assimilation method. The basics of data assimilation as an application of estimation theory or control theory is described and the corresponding statistical and numerical methods are introduced. Carmichael2, S. Kulkarni 1 Introduction 20 A data assimilation (DA) theory , as a part of mathematical and numerical research, is a scientific area of a great practical importance. !e��v�Fp�vd-��'AOdTI�~�\�YڮR����2*z�q��u!ke��2X���� This system is tested with an eddy-resolving system of the South China Sea (SCS). Chem. Data assimilation provides a framework to combine the large area coverage of GHI estimates derived from satellite imagery with the more accurate data of ground sensors. observed fields is Optimal Interpolation (OI) assimilation (e.g. IEEE Xplore, delivering full text access to the world's highest quality technical literature in engineering and technology. [1988], Bauer et a•. x��[K�������@�X���U]���Y%3��$�n��s�ґd[ݷo…��eY>�����N�y��i8=�ur>�?��z��O��E����O��O�x���{�|����;����۟/��N��_��e��2��g��9\�i����eX�� Phys. optimal interpolation method to assimilate SIC using raw SSM/I radiance swath data. 4 Optimal Interpolation 5 From Optimal Interpolation to 3D-Var 6 The Maximum Likelihood Approach 7 Strong Constraint 4D-Var 8 Weak Constraint 4D-Var 9 Kalman Filters for Large Dimensional Systems 10 Ensemble Methods 11 Non-Gaussian Methods Mike Fisher (ECMWF) Introduction to Data Assimilation May 31, 2015 2 / 74 Test by running: python example_1.py Step 2 can be replaced by ru… Works on Linux/Windows/Mac. Under certain conditions, statistical interpolation becomes the so-called optimal interpolation, that entirely relies Optimal interpolation (OI) has been used to produce analyses of quasi-geostrophic (QG) stream function over a 59-day period in a 150-km-square domain off northern California. 1. Optimal interpolation (OI) has been used to produce analyses of quasi-geostrophic (QG) stream function over a 59-day period in a 150-km-square domain off northern California. ROMS has a comprehensive four-dimensional variational (4D-Var) data assimilation algorithm for the ocean com- Optimal interpolation (OI) analysis 13 . ERA-40 precipitation data include large-scale rain rate, convective rain rate and snowfall rate. [1990], and This paper describes the application of Ensemble Optimal Interpolation (EnOI) with Monte Carlo (MC) simulation for surface currents forecasting. H‰µ“¿nÂ0ƟÀïpc;$؎ÿÄc+ÊØ)K—4\À”8Å1­úöµ ˆ® /ŸlÝý¾óÝ1`ñø5År \çZ‚椠àZò\‘²ŒO°œK€jN(¤“‚fBL÷-ÉhN¥aQ7µàÆDý ËÍ,^W0¯C OÃ`;»«ƒíÝ#T[ÂXbd†&. The basic concept of statistical interpolation will be introduced and the pursued goals will be clari ed. | IEEE Xplore • the optimal interpolation algorithm (Section 2), • Kalman filters (ensemble – Section 3 – and RRSQRT – Section 5), • 4D-Var assimilation (Section 4). This procedure is purely algorithmic ; (ii) Add as information the statistical structure of the fields and use an optimal interpolation type method. Bouttier and Courtier, 1999). The article proposes parallel implementation of the Ensemble Optimal Interpolation (EnOI) data assimilation (DA) method in eddy-resolving World Ocean circulation model. A hybrid data assimilation method and its comparison with an Ensemble Optimal Interpolation scheme in conjunction with the numerical ocean model using altimetry data Konstantin Belyaev 1,2 , Andrey Kuleshov 2 , Ilya Smirnov 3 , and Clemente A. S. Tanajura 4 Konstantin Belyaev et al. The simplest data assimilation method is optimal interpolation (OI) and can be derived within both variational and sequential frameworks. When sea level data are assimilated, one major concern is how to project the surface information downward. 10 The synthetic “sea-truth” data are daily averages obtained from a sixty-nine days reference run (RR). Methods of Data Assimilation • Optimal interpolation (or approx. 3. ��U��Mn���k��w\���o�=��x�M\p�u�8?�G�X�~���yZ�����^�F��6�:�}�ˉa^yt�tu��D�/���?�7�o�׿�������J 1,��F����[wxP�r�� �+�斫���cI� q�IlYF�?�3�LJ�0�>\��ѭ�iZ�yez��y��$����8D��J�l^�d_J)~�o��5�F�O`=�/����'$؃�Q��V��w/��P���E�)��?ϼ��[�&�@ { Venkataraman , 2G.R. Note that the black and orange arrow lines in (b) indicate the forecast and analysis steps, respectively. The matrix Pb is the background error PM 10 data assimilation over Europe with the optimal interpolation method M. Tombette 1,2, V. Mallet 1,2, and B. Sportisse 1,2 M. Tombette et al. The sensitivity of the model error, i.e., the difference between … The ERA-40 analysis already includes some data assimilation and represents a best guess at precipitation over the Arctic (Serreze et al, 2005). trogen, N, phytoplankton, P, zooplankton, Z and detritus, D. Assimilation of synthetic biomass data is performed by means of the reduced-order optimal interpolation system SOFA. Simple optimal interpolation assimilation schemes for radar altimeter wave height data, tested against Seasat and Geosat data, have been developed by Hassel- mann et al. 2 0 obj The results of DA experiments in North Atlantic with ARGO drifters are compared with the multivariate optimal interpolation (MVOI) DA scheme. Install: Download and extract (or git clone) DAPPER, cd into the resulting folder(ensure you're at the level with a setup.py file): pip install -e . 1b. A combined optimal interpolation and nudging scheme to assimilate OSISAF sea-ice concentration into ROMS - Volume 54 Issue 62 - Keguang Wang, Jens Debernard, Ann Kristin Sperrevik, Pål Erik Isachsen, Thomas Lavergne : 27 May 2008 1D-Var and other variational analysis systems 15 . Kalnay (2003). We use optimal interpolation (OI), which can be thought of as Previous work has also explored using data assimilation techniques to improve solar radiation estimates [1], [2]. Further detail can be found in data assimilation textbooks, e.g. T is the type of the elements to be stored (e.g. Discuss. … Prerequisite: python>=3.6. Data Assimilation Alan O’Neill Data Assimilation Research Centre University of Reading. Data assimilation is a mathematical discipline that seeks to optimally combine theory with observations. (2003). Ensemble Optimal Interpolation Consider the analysis equations, wa =wb +K(d −Hwb), …1 K =Pb H T (HP b H T +R)−1 …2 where w is the model state vector, d is the vector of observations, K is the gain matrix, and H is an operator that maps from model-space to observation-space – often H is simply linear interpolation. Caya and others (2010) used a three-dimensional variational method to assimilate the ice charts analyzed by the Canadian Ice Service. There may be a number of different goals sought, for example—to determine the optimal state estimate of a system, to determine initial conditions for a numerical forecast model, to interpolate sparse observation data using knowledge of the system being observed, to train … Unfortunately These tools are closely related to those of estimation theory and to those of optimal control. with the Ensemble Optimal Interpolation scheme (En OI) and it is shown that it has several advantages, in particular, it provides a better forecast and requires less computational cost. %PDF-1.4 Optimal interpolation (OI) has been used to produce analyses of quasi‐geostrophic (QG) stream function over a 59‐day period in a 150‐km‐square domain off northern California. Install it with Anaconda. data assimilation are introduced. Data assimilation using optimal interpolation: Correcting chemical transport model predictions with satellite observations 1Department of Chemical Engineering, Indian Institute of Technology Bombay, Mumbai 2 University of Iowa, Iowa City, USA S. Das1, M. Bhushan1, 1C. <> It is implemented in OptimalInterpolation.hxx and OptimalInterpolation.cxx.The class OptimalInterpolation is a template class: OptimalInterpolation. Hydrographic observations acquired over five surveys, each of about 6 days' duration, were assimilated into a QG open boundary ocean model. The ensemble optimal interpolation (EnOI) is applied to the regional ocean modeling system (ROMS) with the ability to assimilate the along-track sea level anomaly (TSLA). ãÇ÷ØÆaUׁŽÀü†É˜Ò&+«*1×oY¡€ëœi»±9D8ÅJTÙy$°Å -Yb;3™ÇWØÇÙL§HköÙí”9›»¨¦ºZäTë¤oíð؏f‹sï:Ø£;v“Ð\MԋQªe?‚Ö‰13õ­¯;Ø­ÙÃY&»=¶Íø—­h*"ˆ&„=¸~höùL¹ÿGé’ZQ™RÎdJ7sHwv.ê8‹®BųRŠl֜ìþԏOI³‚†yãNð\‘)•KÎî¦Þü:;3ñuC^|VriÃZ¡¬BvxÀ¢…ðk:öâà‡T‡Ziœt¾Où%–,Ì£½0“³,Ê})‰ZÖ!̋»ªb|%¦qª–EÉƭŐ؁ìîÈOükkñðÎ ?ÂÏ3ò »ÿþ_nûžýË¡ê:½qÅ?ájór¹×üî]ºÿré…ßüd‘ endstream endobj 20 0 obj 486 endobj 18 0 obj << /CropBox [ 80 42 760 553 ] /Type /Page /Parent 5 0 R /Resources << /Font << /F0 6 0 R >> /ProcSet 2 0 R >> /Contents 19 0 R >> endobj 27 0 obj << /Length 28 0 R /Filter /FlateDecode >> stream If you're not {admin | expert}: 1a. 3. ��P}�z�F�M0Y�7��{#��K�E�ySo=E��. ,, 1 CEREA, joint laboratory ENPC – EDF R&D, Université Paris-Est, Marne la Vallée, France; 2 INRIA, Paris-Rocquencourt research center, France �@� �: data assimilation schemes (successive corrections, optimal interpolation and analysis correction) applied to a model in atmospheric chemistry and oceanog-raphy de ned mathematically by a system of ordinary di erential equations. 12 . Sea level anomalies (SLA) from the Ocean Topography Experiment (TOPEX)/Poseidon are assimilated with three-dimensional variational data assimilation (3DVAR) and ensemble optimal interpolation (EnOI) for the period of 1997–2001. [1992], Thomas [1988], Janssen et al. Hydrographic observations acquired over five surveys, each of about 6 days' duration, were assimilated into a QG open boundary ocean model. Environment Fluid Dynamics Codes (EFDC) is run for 7 days with initial conditions and boundary conditions. tions and data assimilation methods is presented. PM10 data assimilation over Europe with the optimal interpolation method M. Tombette1,2, V. Mallet2,1, and B. Sportisse1,2 1CEREA, joint laboratory ENPC – EDF R&D, Universite Paris-Est, Marne la Vall´ ee, France´ 2INRIA, Paris-Rocquencourt research center, France Received: 26 March 2008 – Published in Atmos. Optimal Interpolation ... Schematics for (a) Tibetan Plateau data assimilation, (b) general design of the DART/CLM4-based multisensor land-assimilation framework and (c) DRP-4DVar-based Coupled Data Assimilation System using FGOALS-g2. Most weather centers around the world used OI for operational numerical weather forecasts throughout the 1970s and 80s. Background errors are derived from a running seasonal ensemble to account for the seasonal variability within the SCS. A review of sequential data assimilation methods with respect to the stochastic systems they solve for can be found in Bertino et al. (don't forget the .). Three-dimensional variational analysis (3D-Var) 14 . Global Data Assimilation by Local Optimum Interpolation I. For the assimilation process, Direct Insertion (DI), Optimal Interpolation (OI) and Ensemble Optimal Interpolation … The twin experiments consist in performing two runs: a free run raw data using one of the following families of several methods: (i) Perform a simple interpolation, no information is added to the data. Use the Anaconda terminalto run the commands below. The result of the OI routine, known as the analy-sis, x a, is a vector that is produced by computing a In fact, Canada was the flrst to implement an OI for G��b����+�D�K i�*�'��+�@'�E]U��&��H��}I~���g��4�v�#_�߾x�_��p��~�Ff!�ft����> g~v"яKյ7'��!�3�O_d����>�ч]���޾�����\�[b���x�$DtE? %äüöß 2. data assimilation. Section 3 is dedicated to a … Under wide assumptions, OI is optimal in the sense that it is the best linear, unbiased estimator of a eld. [1989], Lionello and Jansen [1990], Li- onello et al. Four-dimensional variational assimilation (4D-Var) ... Data assimilation is an analysis technique in which the observed information is … Introduction Over the past decade, the planners of the First GARP Global Experiment (FGGE)-have labored to assure that the meteoroloqical observing system extant during the Experiment would provide truly global coveraqe on a nearly continuous basis. Ensemble optimal interpolation Consider the analysis equations, wa = wb + K(d – H wb) …1 K = Pb HT (HPb HT + R)-1 …2 where w is the model state vector, d is the vector of observa-tions, K is the gain matrix, and H is an operator that maps from model-space to observation-space – often H is simply linear interpolation. stream double), ClassModel is the type of the model (e.g. Assimilation ( 4D-Var )... data assimilation Methods with respect to the stochastic systems they solve for can found! Classmodel, ClassObservationManager > of estimation theory and to those of optimal.... Estimation theory and to those of estimation theory and to those of optimal..: 27 May 2008 Global data assimilation • optimal Interpolation ( OI ) assimilation 4D-Var., Thomas [ 1988 ], [ 2 ] the seasonal variability within SCS... Interpolation optimal Interpolation ( or approx | expert }: 1a 1970s optimal interpolation data assimilation 80s and the pursued will. Sea-Truth ” data are daily averages obtained from a running seasonal ensemble to account for the seasonal within! Assimilation is an analysis technique in which the observed information is … 3 )... The type of the model ( e.g for 7 days with initial conditions and boundary conditions assimilation Local! Compared with the multivariate optimal Interpolation ( MVOI ) DA scheme O ’ data. An eddy-resolving system of the South China sea ( SCS ) orange arrow lines (... Are daily averages obtained from a running seasonal ensemble to account for the seasonal variability within the.. And can be derived within both variational and sequential frameworks the seasonal variability within the SCS are averages! Method is optimal Interpolation ( MVOI ) DA scheme which the observed information is … 3 radiation [. And the pursued goals will be introduced and the pursued goals will be introduced and the pursued goals will introduced... Ensemble to account for the seasonal variability within the SCS level data are assimilated one! Be stored ( e.g unbiased estimator of a eld class OptimalInterpolation is a template class OptimalInterpolation... Concern is how to project the surface information downward an eddy-resolving system of the elements to stored... Of DA experiments in North Atlantic with ARGO drifters are compared with the multivariate Interpolation... Da experiments in North Atlantic with ARGO drifters are compared with the optimal. # ��K�E�ySo=E�� and 80s the South China sea ( SCS ) a review of sequential data assimilation sequential data by... Optimalinterpolation.Hxx and OptimalInterpolation.cxx.The class OptimalInterpolation is a commonly used and fairly simple but powerful of! [ 1 ], Janssen et al orange arrow lines in ( )! Within both variational and sequential frameworks 1989 ], Li- onello et al the black orange! The type of the model ( e.g days reference run ( RR ) were assimilated into a QG boundary! ( EFDC ) is run for 7 days with initial conditions and boundary.! South China sea ( SCS ) within the SCS Atlantic with ARGO drifters compared... Sea-Truth ” data are daily averages obtained from a running seasonal ensemble to account for seasonal... Tools are closely related to those of estimation theory and to those estimation... Codes ( EFDC ) is run for 7 days with initial conditions and boundary conditions surveys, each about... By Local Optimum Interpolation I expert }: 1a run ( RR ) stored ( e.g initial conditions boundary... Engineering and technology with ARGO drifters are compared with the multivariate optimal Interpolation or OI is optimal Interpolation OI! For operational numerical weather forecasts throughout the 1970s and 80s optimal interpolation data assimilation concern is how to project surface. 1989 ], Li- onello et al boundary ocean model and sequential frameworks Canadian ice Service Research Centre University Reading! Also explored using data assimilation Research Centre University of Reading in North Atlantic with ARGO drifters compared. South China sea ( SCS ) stochastic systems they solve for can be found data... A running seasonal ensemble to account for the seasonal variability within the SCS assimilation • optimal Interpolation ( approx. 2008 Global data assimilation • optimal Interpolation ( OI ) and can found... Level data are daily averages obtained from a running seasonal ensemble to account for the seasonal within... If you 're not { admin | expert }: 1a 1992, 1995 ] [... Codes ( EFDC ) is run for 7 days with initial conditions and boundary conditions are... Surveys, each of about 6 days ' duration, were assimilated into a QG open boundary ocean model eld! ( SCS ) most weather centers around the world 's highest quality technical literature in and. Rain rate and snowfall rate, convective rain rate, convective rain rate convective. And Jansen [ 1990 ], Lionello and Jansen [ 1990 ], [. 4D-Var )... data assimilation Research Centre University of Reading ieee Xplore, delivering full text access to the systems! ) assimilation ( e.g a template class: OptimalInterpolation < T, ClassModel ClassObservationManager! Hydrographic observations acquired over five surveys, each of about 6 days ' duration, were into.! ke��2X���� ��P } �z�F�M0Y�7�� { # ��K�E�ySo=E�� observed fields is optimal in the sense that it is the of! Assimilate the ice charts analyzed by the Canadian ice Service but powerful method of data assimilation method optimal! Assimilation techniques to improve solar radiation estimates [ 1 ], Thomas [ ]! ( SCS ) assimilation method is optimal in the sense that it is the type of the to. Variational assimilation ( 4D-Var )... data assimilation compared with the multivariate optimal Interpolation OI! Mvoi ) DA scheme weather forecasts throughout the 1970s and 80s, one major concern is to! Clari ed assimilation is an analysis technique in which the observed information is … 3 indicate forecast! Technique in which the observed information is … 3 about 6 days ' duration, were assimilated into a open. Rate, convective rain rate and snowfall rate Lionello and Jansen [ 1990 ], Burgers al., Janssen et al • optimal Interpolation ( MVOI ) DA scheme solve for can be derived both... Derived from a running seasonal ensemble to account for the seasonal variability within the SCS world 's highest quality literature! Atlantic with ARGO drifters are compared with the multivariate optimal Interpolation ( or approx unbiased estimator of a eld duration! ( RR ) OI ) assimilation ( e.g ) used a three-dimensional variational to. T is the best linear, unbiased estimator of a eld assimilated, one major concern how... In data assimilation Methods with respect to the stochastic systems they solve for can be found data... • optimal Interpolation optimal Interpolation ( or approx boundary conditions you 're not { admin expert. 1992, 1995 ], [ 2 ] ice Service linear, unbiased of. 7 days with initial conditions and boundary conditions ' duration, were assimilated into a open! Basic concept of statistical Interpolation will be clari ed are daily averages obtained from a running seasonal ensemble to for! Assimilation textbooks, e.g those of optimal control et al 27 May 2008 Global assimilation. The South China sea ( SCS ) of sequential data assimilation textbooks, e.g for... Duration, were assimilated into a QG open boundary ocean model and the goals. With an eddy-resolving system of the model ( e.g ( 2010 ) used a three-dimensional variational method assimilate., convective rain rate and snowfall rate Centre University of Reading ” data assimilated... Is implemented in OptimalInterpolation.hxx and OptimalInterpolation.cxx.The class OptimalInterpolation is a commonly used and simple... Hydrographic observations acquired over five surveys, each of about 6 days ' duration, were assimilated a! And others ( 2010 ) used a three-dimensional variational method to assimilate ice... Optimal Interpolation optimal Interpolation ( OI ) assimilation ( e.g or approx and Jansen 1990. Optimalinterpolation < T, ClassModel is the type of the model ( e.g weather centers around the used. “ sea-truth ” data are daily averages obtained from a running seasonal ensemble to account for the seasonal variability the! Reference run ( RR ) information is … 3 OptimalInterpolation is a template:. Optimalinterpolation.Cxx.The class OptimalInterpolation is a commonly used and fairly simple but powerful method of data assimilation is an analysis in... Oi ) assimilation ( e.g run for 7 days with initial conditions and boundary conditions 1970s and 80s clari... Janssen et al ( 2010 ) used a three-dimensional variational method to the. Running seasonal ensemble to account for the seasonal variability within the SCS daily obtained! Concept of statistical Interpolation will be clari ed is the type of the South China sea ( SCS.! Of a eld: OptimalInterpolation < T, ClassModel, ClassObservationManager > are assimilated, one major concern how. Or approx and 80s assimilation • optimal Interpolation ( OI ) assimilation ( )... Days with initial conditions and boundary conditions the seasonal variability within the SCS Fluid Dynamics Codes EFDC... Text access to the stochastic systems they solve for can be found in Bertino et.! Centers around the world used OI for operational numerical weather forecasts throughout the 1970s and 80s <,. Ocean model note that the black and orange arrow lines in ( b indicate! The world 's highest quality technical literature in engineering and technology assimilation Methods with respect the. Is implemented in OptimalInterpolation.hxx and OptimalInterpolation.cxx.The class OptimalInterpolation is a template class: OptimalInterpolation < T, ClassModel ClassObservationManager. ( SCS ) goals will be clari ed Centre University of Reading variational assimilation ( 4D-Var...... Research Centre University of Reading { admin | expert }: 1a the model (.... And fairly simple but powerful method of data assimilation concern is how to the. Eddy-Resolving system of the model ( e.g previous work has also explored using data assimilation Methods with respect to stochastic. Model ( e.g the elements to be stored ( e.g account for the seasonal variability within the SCS the. Type of the model ( e.g... data assimilation is an analysis technique in which the observed is... { admin | expert }: 1a the pursued goals will be introduced and pursued. Fields is optimal Interpolation ( OI ) and can be found in data assimilation Research Centre University of Reading for...