variational analysis; vizualizaion; web application
Abstract :
[en] Spatial interpolation of observations on a regular grid is a common task in many oceanographic disciplines (and geosciences in general). It is often used to create climatological maps for physical, biological or chemical parameters representing e.g. monthly or seasonally averaged fields. Since instantaneous observations can not be directly related to a field representing an average, simple spatial interpolation of observations is in general not acceptable. DIVA (Data-Interpolating Variational Analysis) is an analysis tool which takes the error in the observations and the typical spatial scale of the underlying field into account. Barriers due to the coastline and the topography in general and also currents estimates (if available) are used to propagate the information of a given observation spatially.
DIVA is a command-line driven application written in Fortran and Shell Scripts. To make DIVA easier to use, a web interface has been developed (http://gher-diva.phys.ulg.ac.be). Installation and compilation of DIVA is therefore not required. The user can directly upload the data in ASCII format and enter several parameters for the analysis. The analyzed field, location of the observations, and the error mask are presented as different layers using the Web Map Service protocol. They are visualized in the browser using the Javascript library OpenLayers allowing the user to interact with layers (for example zooming and panning). Finally, the results can be downloaded as a NetCDF file, Matlab/Octave file and Keyhole Markup Language (KML) file for visualization in applications such as Google Earth.
Research center :
MARE - Centre Interfacultaire de Recherches en Océanologie - ULiège GeoHydrodynamics and Environment Research Département d'Astrophysique, Géophysique et Océanographie
Disciplines :
Earth sciences & physical geography
Author, co-author :
Barth, Alexander ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > GeoHydrodynamics and Environment Research (GHER) - Département d'astrophys., géophysique et océanographie (AGO)
Alvera Azcarate, Aïda ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > GeoHydrodynamics and Environment Research (GHER)
Troupin, Charles ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > GeoHydrodynamics and Environment Research (GHER)
Ouberdous, Mohamed ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > GeoHydrodynamics and Environment Research (GHER) - Modélisation du climat et des cycles biogéochimiques
Beckers, Jean-Marie ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > GeoHydrodynamics and Environment Research (GHER)
Language :
English
Title :
A web interface for griding arbitrarily distributed in situ data based on Data-Interpolating Variational Analysis (DIVA)
Beckers, J.-M.: Application of a 3D model to the Western Mediterranean, J. Marine Syst., 1, 315-332, 1991.
Brankart, J.-M. and Brasseur, P.: Optimal analysis of in situ data in the Western Mediterranean using statistics and cross-validation, J. Atmos. Ocean. Tech., 13, 477-491, 1996.
Brankart, J.-M. and Brasseur, P.: The general circulation in the Mediterranean Sea: a climatological approach, J. Marine Syst., 18, 41-70, 1998.
Brasseur, P.: Reconstitution de champs d'observations océanographiques par le Modèle Variationnel Inverse: Méthodologie et Applications., Ph. D. thesis, Université de Liège, Collection des publications, Sciences appliquées, 1994.
Brasseur, P., Beckers, J.-M., Brankart, J.-M., and Schoenauen, R.: Seasonal Temperature and Salinity Fields in the Mediterranean Sea: Climatological Analyses of an Historical Data Set., Deep-Sea Res., 43, 159-192, 1996.
Bretherton, F. P., Davis, R. E., and Fandry, C. B.: A technique for objective analysis and design of oceanographic experiment applied to MODE-73, Deep-Sea Res., 23, 559-582, 1976.
Chilès, J.-P. and Delfiner, P.: Geostatistics, Modeling Spatial uncertainty, Wiley Series in Probability and statistics, 1999.
Dhatt, G. and Touzot, G.: Une présentation de la méthode des éléments finis., in: Collection Université de Compiègne, edited by: Paris, Maloine, S. A., 1984.
Dong, S., Xu, S., and Lu, X.: Development of online instructional resources for Earth system science education: An example of current practice from China, Comput. Geosci., 35, 1271-1279, doi:10.1016/j.cageo.2008.08.013, 2009.
Fils, D., Cervato, C., Reed, J., Diver, P., Tang, X., Bohling, G., and Greer, D.: CHRONOS architecture: Experiences with an opensource services-oriented architecture for geoinformatics, Comput. Geosci., 35, 774-782, doi:10.1016/j.cageo.2008.02.035, 2009.
Gandin, L. S.: Objective analysis of meteorological fields, Israel Program for Scientific Translation, Jerusalem, 242 pp., 1965.
Ghoddousi-Fard, R., Dare, P., and Langley, R. B.: A webbased package for ray tracing the neutral atmosphere radiometric path delay, Comput. Geosci., 35, 1113-1124, doi:10.1016/j.cageo.2008.02.027, 2009.
Kruger, A., Khandelwal, S. G., and Bradley, A.: AHPSVER: A web-based system for hydrologic forecast verification, Comput. Geosci., 33, 39-748, doi:10.1016/j.cageo.2006.10.005, 2007. (Pubitemid 46767919)
Luo, W., Peronja, E., Duffin, K., and Stravers, J. A.: Incorporating nonlinear rules in a web-based interactive landform simulation model (WILSIM), Comput. Geosci., 32, 1512-1518, doi: 10.1016/j.cageo.2005.12.012, 2006.
Monahan, D.: GEBCO and Deep Water. Data Assembler, Converter, Interpreter and Disseminator, Hydro International, 11, http://www.gebco.net/, 2007.
Rixen, M., Beckers, J.-M., Levitus, S., Antonov, J., Boyer, T., Maillard, C., Fichaut, M., Balopoulos, E., Iona, S., Dooley, H., Garcia, M.-J., Manca, B., Giorgetti, A., Manzella, G., Mikhailov, N., Pinardi, N., Zavatarelli, M., and the Medar Consortium: The Western Mediterranean Deep Water: a proxy for global climate change, Geophys. Res. Lett., 32, L12608, 2005.
Robinson, A. R.: Physical processes, field estimation and an approach to interdisciplinary ocean modeling, Earth-Sci. Rev., 40, 3-54, 1996.
Schlitzer, R.: Interactive analysis and visualization of geoscience data with Ocean Data View, Comput. Geosci., 28, 1211-1218, doi: 10.1016/S0098-3004 (02) 00040-7, 2002.
Shchepetkin, A. and McWilliams, J.: The Regional Oceanic Modeling System: A split-explicit, free-surface, topography-followingcoordinate ocean model, Ocean Model., 9, 347-404, 2005.
Troupin, C., Machìn, F., Ouberdous, M., Sirjacobs, D., Barth, A., and Beckers, J.-M.: High-resolution Climatology of the North-East Atlantic using Data-Interpolating Variational Analysis (Diva), J. Geophys. Res., 115, C08005, doi:10.1029/2009JC005512, 2010.
Yaremchuk, M. and Sentchev, A.: Mapping radar-derived sea surface currents with a variational method, Cont. Shelf Res., 29, 1711-1722, 2009.
Youn, C., Kaiser, T., Seber, D., and Santini, C.: Webbased simulating system for modeling earthquake seismic wavefields on the grid, Comput. Geosci., 34, 1936-1946, doi:10.1016/j.cageo.2008.02.028, 2008.