A web interface for griding arbitrarily distributed in situ data based on Data-Interpolating Variational Analysis (DIVA)

摘要

Spatial interpolation of observations on a regular grid is a common task in manyoceanographic 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 observationscan not be directly related to a field representing an average, simple spatial interpolation of observations is in generalnot acceptable. DIVA (Data-Interpolating Variational Analysis) is an analysis tool which takes the error in theobservations and the typical spatial scale of the underlying field into account. Barriers due to the coastlineand the topography in general and also currents estimates (if available) are used to propagate the informationof a given observation spatially.DIVA is a command-line driven application written in Fortran andShell Scripts. To make DIVA easier to use, a web interface has been developed(). 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 differentlayers using the Web Map Service protocol. They are visualized in the browser using the Javascriptlibrary 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.