{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:16:40Z","timestamp":1760242600187,"version":"build-2065373602"},"reference-count":65,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2017,12,19]],"date-time":"2017-12-19T00:00:00Z","timestamp":1513641600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>A variety of data assimilation approaches have been applied to enhance modelling capability and accuracy using observations from different sources. The algorithms have varying degrees of complexity of implementation, and they improve model results with varying degrees of success. Very little work has been carried out on comparing the implementation of different data assimilation algorithms using High Frequency radar (HFR) data into models of complex inshore waters strongly influenced by both tides and wind dynamics, such as Galway Bay. This research entailed implementing four different data assimilation algorithms: Direct Insertion (DI), Optimal Interpolation (OI), Nudging and indirect data assimilation via correcting model forcing into a three-dimensional hydrodynamic model and carrying out detailed comparisons of model performances. This work will allow researchers to directly compare four of the most common data assimilation algorithms being used in operational coastal hydrodynamics. The suitability of practical data assimilation algorithms for hindcasting and forecasting in shallow coastal waters subjected to alternate wetting and drying using data collected from radars was assessed. Results indicated that a forecasting system of surface currents based on the three-dimensional model EFDC (Environmental Fluid Dynamics Code) and the HFR data using a Nudging or DI algorithm was considered the most appropriate for Galway Bay. The largest averaged Data Assimilation Skill Score (DASS) over the \u22656 h forecasting period from the best model NDA attained 26% and 31% for east\u2013west and north\u2013south surface velocity components respectively. Because of its ease of implementation and its accuracy, this data assimilation system can provide timely and useful information for various practical coastal hindcast and forecast operations.<\/jats:p>","DOI":"10.3390\/rs9121331","type":"journal-article","created":{"date-parts":[[2017,12,19]],"date-time":"2017-12-19T10:48:40Z","timestamp":1513680520000},"page":"1331","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Comparative Study on Assimilating Remote Sensing High Frequency Radar Surface Currents at an Atlantic Marine Renewable Energy Test Site"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9662-8630","authenticated-orcid":false,"given":"Lei","family":"Ren","sequence":"first","affiliation":[{"name":"College of Engineering and Informatics, National University of Ireland Galway, H91 TK33 Galway, Ireland"},{"name":"Ryan Institute, H91 TK33 Galway, Ireland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Michael","family":"Hartnett","sequence":"additional","affiliation":[{"name":"College of Engineering and Informatics, National University of Ireland Galway, H91 TK33 Galway, Ireland"},{"name":"Ryan Institute, H91 TK33 Galway, Ireland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2017,12,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"115","DOI":"10.1146\/annurev-marine-121211-172315","article-title":"High-Frequency Radar Observations of Ocean Surface Currents","volume":"5","author":"Paduan","year":"2013","journal-title":"Ann. Rev. Mar. Sci."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"2647","DOI":"10.1002\/2017JC012961","article-title":"Ocean surface currents from satellite data","volume":"122","author":"Dohan","year":"2017","journal-title":"J. Geophys. Res."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"94","DOI":"10.5670\/oceanog.2010.08","article-title":"Monitoring ocean currents with satellite sensors","volume":"23","author":"Dohan","year":"2010","journal-title":"Oceanography"},{"key":"ref_4","first-page":"63","article-title":"Surface Kuroshio path in the Luzon Strait area derived from satellite remote sensing data","volume":"111","author":"Yuan","year":"2006","journal-title":"J. Geophys. Res."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"989","DOI":"10.1007\/s10236-014-0724-7","article-title":"High-resolution X-Band radar measurements of currents, bathymetry and sea state in highly inhomogeneous coastal areas","volume":"64","author":"Hessner","year":"2014","journal-title":"Ocean Dyn."},{"key":"ref_6","first-page":"75","article-title":"Assimilation of HF radar-derived surface currents on tidal-timescales","volume":"5","author":"Gopalakrishnan","year":"2012","journal-title":"J. Oper. Oceanogr."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"2343","DOI":"10.5194\/hess-18-2343-2014","article-title":"The suitability of remotely sensed soil moisture for improving operational flood forecasting","volume":"18","author":"Wanders","year":"2014","journal-title":"Hydrol. Earth Syst. Sci."},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Pan, X., Li, X., Cheng, G., and Hong, Y. (2017). Effects of 4D-Var Data Assimilation Using Remote Sensing Precipitation Products in a WRF Model over the Complex Terrain of an Arid Region River Basin. Remote Sens., 9.","DOI":"10.3390\/rs9090963"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"587","DOI":"10.1175\/MWR-D-11-00023.1","article-title":"E4DVar: Coupling an Ensemble Kalman Filter with Four-Dimensional Variational Data Assimilation in a Limited-Area Weather Prediction Model","volume":"140","author":"Zhang","year":"2012","journal-title":"Mon. Weather Rev."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"269","DOI":"10.1175\/2008MWR2500.1","article-title":"A Sequential Variational Algorithm for Data Assimilation in Oceanography and Meteorology","volume":"137","author":"Dobricic","year":"2009","journal-title":"Mon. Weather Rev."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"103","DOI":"10.1175\/1520-0493(2002)130<0103:HDAWTE>2.0.CO;2","article-title":"Hydrologic Data Assimilation with the Ensemble Kalman Filter","volume":"130","author":"Reichle","year":"2002","journal-title":"Mon. Weather Rev."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1445","DOI":"10.1002\/qj.2054","article-title":"Operational implementation of a hybrid ensemble\/4D-Var global data assimilation system at the Met Office","volume":"139","author":"Clayton","year":"2013","journal-title":"Q. J. R. Meteorol. Soc."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"149","DOI":"10.1016\/j.dsr2.2008.08.004","article-title":"Assimilation of HF radar-derived radials and total currents in the Monterey Bay area","volume":"56","author":"Shulman","year":"2009","journal-title":"Deep Sea Res. Part II"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"659","DOI":"10.5194\/npg-21-659-2014","article-title":"Assimilation of HF radar surface currents to optimize forcing in the Northwestern Mediterranean Sea","volume":"21","author":"Marmain","year":"2014","journal-title":"Nonlinear Process. Geophys."},{"key":"ref_15","first-page":"328","article-title":"Assimilation of high-frequency radar currents in a nested model of the West Florida Shelf","volume":"113","author":"Barth","year":"2008","journal-title":"J. Geophys. Res."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"157","DOI":"10.1016\/j.jmarsys.2015.09.006","article-title":"Impacts of a 4-dimensional variational data assimilation in a coastal ocean model of southern Tyrrhenian Sea","volume":"154","author":"Iermano","year":"2016","journal-title":"J. Mar. Syst."},{"key":"ref_17","unstructured":"Dabrowski, T. (2005). A Flushing Study Analysis of Selected Irish Waterbodies. [Ph.D. Thesis, National University of Ireland Galway]."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"345","DOI":"10.1016\/j.wse.2015.12.001","article-title":"Observation and modeling of tide- and wind-induced surface currents in Galway Bay","volume":"8","author":"Ren","year":"2015","journal-title":"Water Sci. Eng."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"96","DOI":"10.1016\/j.jmarsys.2014.10.004","article-title":"Characterizing observed circulation patterns within a bay using HF radar and numerical model simulations","volume":"142","author":"Hartnett","year":"2015","journal-title":"J. Mar. Syst."},{"key":"ref_20","unstructured":"Hamrick, J.M. (2007). The Environmental Fluid Dynamics Code Theory and Computation Volume 1: Hydrodynamics and Mass Transport, Tetra Tech, Inc."},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Baguis, P., and Roulin, E. (2017). Soil Moisture Data Assimilation in a Hydrological Model: A Case Study in Belgium Using Large-Scale Satellite Data. Remote Sens., 10.","DOI":"10.3390\/rs9080820"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"2","DOI":"10.3402\/tellusa.v44i1.14938","article-title":"Chaos and quadri-dimensional data assimilation: A study based on the Lorenz model","volume":"44","author":"Gauthier","year":"1992","journal-title":"Tellus"},{"key":"ref_23","unstructured":"Wen, L. (1995). Three-Dimensional Hydrodynamic Modelling in Galway Bay. [Ph.D. Thesis, University College Galway]."},{"key":"ref_24","unstructured":"Booth, D. (1975). The Water Structure and Circulation of Killary Harbour and of Galway Bay. [Ph.D. Thesis, National University of Ireland]."},{"key":"ref_25","unstructured":"Fernandes, L. (1988). A Study of the Oceanography of Galway Bay, Mid-Western Coastal Waters (Galway Bay to Bralle Bay), Shannon Estuary and the Rive Shannon Plume. [Ph.D. Thesis, National University of Ireland Galway]."},{"key":"ref_26","unstructured":"BIM (2012). Environmental Impact Statement (EIS) for Deep Sea Fish Farm Development in Galway Bay, Co. Galway, Ireland, Irish Sea Fisheries Board."},{"key":"ref_27","unstructured":"Nolan, G.D. (1997). A Study of the River Corrib Plume and its Associated Dynamics in Galway Bay during the Winter Months. [Master\u2019s Thesis, University College Galway]."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"471","DOI":"10.1017\/S0025315412001348","article-title":"The role of wind-forcing in the distribution of larval fish in Galway Bay, Ireland","volume":"93","author":"Comerford","year":"2013","journal-title":"J. Mar. Assoc. U. K."},{"key":"ref_29","unstructured":"Hamrick, J.M. (1992). A Three-Dimensional Environmental Fluid Dynamics Computer Code: Therotical and Computatonal Aspects, Virginia Institute of Marine Science."},{"key":"ref_30","unstructured":"Hamrick, J.M. (2006). EFDC Technical Memorandum, Tetra Tech."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"555","DOI":"10.1061\/(ASCE)0733-9372(2006)132:4(555)","article-title":"Integrated Hydrodynamic and Water Quality Modeling System to Support Nutrient Total Maximum Daily Load Development for Wissahickon Creek, Pennsylvania","volume":"132","author":"Zou","year":"2006","journal-title":"J. Environ. Eng."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"1055","DOI":"10.1061\/(ASCE)0733-9429(2004)130:11(1055)","article-title":"Case Study: Modeling of Sediment Transport and Wind-Wave Impact in Lake Okeechobee","volume":"130","author":"Jin","year":"2004","journal-title":"J. Hydraul. Eng."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"14","DOI":"10.1016\/j.aquaeng.2012.07.006","article-title":"Physical and numerical investigation of the hydrodynamic implications of aquaculture farms","volume":"52","author":"Hartnett","year":"2013","journal-title":"Aquac. Eng."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"457","DOI":"10.1016\/j.renene.2015.01.024","article-title":"Numerical modelling of the wave energy in Galway Bay","volume":"78","author":"Bento","year":"2015","journal-title":"Renew. Energy"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"183","DOI":"10.1175\/1520-0426(2002)019<0183:EIMOBO>2.0.CO;2","article-title":"Efficient Inverse Modeling of Barotropic Ocean Tides","volume":"19","author":"Egbert","year":"2002","journal-title":"J. Atmos. Ocean. Technol."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1029\/2003GL019003","article-title":"A barotropic inverse tidal model for the Arctic Ocean","volume":"31","author":"Padman","year":"2004","journal-title":"Geophys. Res. Lett."},{"key":"ref_37","unstructured":"Wang, J., Dizaji, R., and Ponsford, A.M. (2004, January 2\u20135). Analysis of clutter distribution in bistatic high frequency surface wave radar. Proceedings of the Conference on Electrical & Computer Engineering, Niagara Falls, ON, Canada."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"553","DOI":"10.1006\/ecss.2000.0704","article-title":"Remote Radar Measurement of Shelf Currents off Key Largo, Florida, U.S.A","volume":"51","author":"Haus","year":"2000","journal-title":"Estuar. Coast. Shelf Sci."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"1259","DOI":"10.1175\/1520-0426(2004)021<1259:ERCMFC>2.0.CO;2","article-title":"Evaluating radial current measurements from CODAR High-Frequency radars with moored current meters","volume":"21","author":"Emery","year":"2004","journal-title":"J. Atmos. Ocean. Technol."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"184","DOI":"10.1080\/02723646.1981.10642213","article-title":"On the validation of models","volume":"2","author":"Willmott","year":"1981","journal-title":"Phys. Geogr."},{"key":"ref_41","first-page":"1","article-title":"Forecasting of Surface Currents via Correcting Wind Stress with Assimilation of High-Frequency Radar Data in a Three-Dimensional Model","volume":"2016","author":"Ren","year":"2016","journal-title":"Adv. Meteorol."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"271","DOI":"10.1016\/S0278-4343(98)00078-8","article-title":"An EOF analysis of HF Doppler radar current measurements of the Chesapeake Bay buoyant outflow","volume":"19","author":"Marmorino","year":"1999","journal-title":"Cont. Shelf Res."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"122","DOI":"10.4031\/MTSJ.44.6.6","article-title":"The Intergrated Ocean Observing System High-Frequency Radar Network: Status and Local, Regional and National Applications","volume":"44","author":"Harlan","year":"2010","journal-title":"Mar. Technol. Soc. J."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"247","DOI":"10.1016\/S1353-2561(97)00022-4","article-title":"Assimilation of Radar Measured Surface Current Fields into a Numerical Model for Oil Spill Modelling","volume":"3","author":"Tinis","year":"1996","journal-title":"Spill Sci. Technol. Bull."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"238","DOI":"10.1016\/j.marpolbul.2008.09.020","article-title":"Application of HF radar currents to oil spill modelling","volume":"58","author":"Abascal","year":"2009","journal-title":"Mar. Pollut. Bull."},{"key":"ref_46","first-page":"95","article-title":"Toward an integrated HF radar network in the Mediterranean Sea to improve search and rescue and oil spill response: The TOSCA project experience","volume":"8","author":"Bellomo","year":"2015","journal-title":"J. Oper. Oceanogr."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"161","DOI":"10.1016\/S0924-7963(01)00002-1","article-title":"Real time assimilation of HF radar currents into a coastal ocean model","volume":"28","author":"Breivik","year":"2001","journal-title":"J. Mar. Syst."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"117","DOI":"10.1007\/s10236-016-1012-5","article-title":"Correction of inertial oscillations by assimilation of HF radar data in a model of the Ligurian Sea","volume":"67","author":"Vandenbulcke","year":"2017","journal-title":"Ocean Dyn."},{"key":"ref_49","doi-asserted-by":"crossref","unstructured":"Isern-Fontanet, J., Ballabrera-Poy, J., Turiel, A., and Garcia-Ladona, E. (2017). Retrieval and assimilation of velocities at the ocean surface. Nonlinear Process. Geophys., 1\u201338.","DOI":"10.5194\/npg-2017-14"},{"key":"ref_50","first-page":"747","article-title":"Recent advances and development of data assimilation algorithms","volume":"27","author":"Ma","year":"2012","journal-title":"Adv. Earth Sci."},{"key":"ref_51","first-page":"570","article-title":"Oceanic data assimilation study in northern Chile: Use of a 3DVAR method","volume":"41","author":"Marchesiello","year":"2013","journal-title":"Latin Am. J. Aquat. Res."},{"key":"ref_52","unstructured":"Soares, C.G. (2015). Data Assimilation with High-Frequency (HF) Radar Surface Currents at a Marine Renewable Energy Test Site. Renewable Energies Offshore, CRC Press. Chapter 24."},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"81","DOI":"10.1016\/j.cageo.2016.10.012","article-title":"Sensitivity analysis of a data assimilation technique for hindcasting and forecasting hydrodynamics of a complex coastal water body","volume":"99","author":"Ren","year":"2016","journal-title":"Comput. Geosci."},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"1","DOI":"10.3390\/rs9090932","article-title":"Hindcasting and Forecasting of Surface Flow Fields through Assimilating High Frequency Remotely Sensing Radar Data","volume":"9","author":"Ren","year":"2017","journal-title":"Remote Sens."},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"1784","DOI":"10.1016\/j.rser.2015.05.068","article-title":"Adaptive neuro-fuzzy approach for solar radiation prediction in Nigeria","volume":"51","author":"Olatomiwa","year":"2015","journal-title":"Renew. Sustain. Energy Rev."},{"key":"ref_56","unstructured":"Daley, R. (1993). Atmospheric Data Analysis, Cambridge University Press."},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"981","DOI":"10.1002\/qj.74","article-title":"Data assimilation in the FOAM operational short-range ocean forecasting system: A description of the scheme and its impact","volume":"133","author":"Martin","year":"2007","journal-title":"Q. J. R. Meteorol. Soc."},{"key":"ref_58","doi-asserted-by":"crossref","first-page":"460","DOI":"10.7763\/IJCCE.2014.V3.369","article-title":"Sensitivity tests of direct insertion data assimilation with pseudo measurements","volume":"3","author":"Ren","year":"2014","journal-title":"Int. J. Comput. Commun. Eng."},{"key":"ref_59","doi-asserted-by":"crossref","first-page":"1001","DOI":"10.1016\/j.csr.2004.02.013","article-title":"Assimilation of drifter and satellite data in a model of the Northeastern Gulf of Mexico","volume":"24","author":"Fan","year":"2004","journal-title":"Cont. Shelf Res."},{"key":"ref_60","first-page":"395","article-title":"Altimetry and drifter data assimilations of loop current and eddies","volume":"112","author":"Lin","year":"2007","journal-title":"J. Geophys. Res."},{"key":"ref_61","unstructured":"Gopalakrishnan, G. (2008). Surface Current Observations Using High Frequency Radar and Its Assimilation into the New York Harbor Observing and Prediction System. [Ph.D. Thesis, Stevens Institute of Technology]."},{"key":"ref_62","doi-asserted-by":"crossref","first-page":"541","DOI":"10.1016\/S0278-4343(98)00006-5","article-title":"Assimilation of Doppler radar current data into numerical ocean models","volume":"18","author":"Lewis","year":"1998","journal-title":"Cont. Shelf Res."},{"key":"ref_63","doi-asserted-by":"crossref","first-page":"209","DOI":"10.1007\/BF02108528","article-title":"Local balance in the air-sea boundary processes","volume":"29","author":"Toba","year":"1973","journal-title":"J. Oceanogr. Soc. Jpn."},{"key":"ref_64","doi-asserted-by":"crossref","first-page":"994","DOI":"10.1175\/1520-0493(1976)104<0994:ACFFOA>2.0.CO;2","article-title":"Anisotropic Correction Functions for Objective Analysis","volume":"104","author":"Thiebaux","year":"1976","journal-title":"Mon. Weather Rev."},{"key":"ref_65","doi-asserted-by":"crossref","unstructured":"Ragnoli, E., Zhuk, S., O\u2019Donncha, F., Suits, F., and Hartnett, M. (2012, January 14\u201319). An Optimal Interpolation Scheme for Assimilation of HF Radar Current Data into a Numerical Ocean Model. Proceedings of the Oceans, Hampton Roads, VA, USA.","DOI":"10.1109\/OCEANS.2012.6404901"}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/9\/12\/1331\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T18:54:35Z","timestamp":1760208875000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/9\/12\/1331"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2017,12,19]]},"references-count":65,"journal-issue":{"issue":"12","published-online":{"date-parts":[[2017,12]]}},"alternative-id":["rs9121331"],"URL":"https:\/\/doi.org\/10.3390\/rs9121331","relation":{},"ISSN":["2072-4292"],"issn-type":[{"type":"electronic","value":"2072-4292"}],"subject":[],"published":{"date-parts":[[2017,12,19]]}}}