Using the Network Common Data Form for storage of atmospheric data

Transcription

1 Using the Network Common Data Form for storage of atmospheric data Maarten Plieger Royal Netherlands Meteorological Institute The NetCDF4 data format (Network Common Data Form) is used within the ADAGUC project for the storage of atmospheric data

2 Introduction The ADAGUC project Adaguc file standard NetCDF4 data format Climate & Forecast (CF) conventions GDAL/OGR Drivers OGC Webservices WMS, WFS, WCS ADAGUC files in GIS

3 ADAGUC Atmospheric Data Access for the Geospatial User Community Bridging different sciences Atmospheric Datasets in GIS systems Standard data format for all data Open Standards OGC Connect with GIS clients through OGC standards This project is sponsored by Space for Geo-Information

4 Instruments: Sciamachy GOME OMI AMSR Precipitation radar Raster Datasets Datasets: Current data types: Raster Vector Soil Moisture FRESCO NO 2 CH 4 CO O 3 Precipitation Vector Goal: Store data in a generic format and provide access to the data by using standard OGC Services

5 Adaguc file standard NetCDF 4 data format Metadata conventions: INSPIRE compliant: ISO NL kernset Metadata Standard Climate and Forecast metadata conventions 1.4 Data and metadata reside in the same file ISO metadata describes the data on dataset level Climate and forecast conventions describes the data level ISO core set CF Conventions 1.4 EU core set (CEN TC 287) NL core set ADAGUC metadata

6 Network Common Data Form 4 (netcdf 4) Joint project between Unidata and HDF Group NetCDF 4 uses HDF5 as the storage layer of NetCDF Programming interfaces are backward compatible with the netcdf3 programming interface NetCDF3 popular, simple, lots of tools, multiple implementations NetCDF4 HDF5 powerful, high-performance, storage efficiency, extensibility Best of both formats combined!

7 Climate & forecast (CF) conventions Standard names, standard units Identify and compare data Locate data in space time and as a function of other independent variables Coordinate variables:

8 Structure of an ADAGUC file iso_dataset: The same for each file from this dataset product: Can be different for each file attributes with metadata coordinate variable data

9 Unique identifiers (UUID) Unique identifiers to make the data distinguishable Google on UID provides the description of the data!

10 GDAL / OGR GDAL/OGR drivers Open source translator library for raster geospatial data formats Used in many software products UMN MapServer, GeoServer, Quantum GIS, ArcGIS, GRASS, OpenEV etc.. GDAL - Geospatial Data Abstraction Library Access raster data OGR - Simple Feature Library Access vector data GDAL/OGR extensions available with support for the ADAGUC data standard trac.osgeo.org/gdal/wiki/adaguc

11 OGC Webservices Why OpenGIS services? Data discovery Multiple output formats Resampling/ interpolation Spatial/temporal selections Connection to GIS programs Enabled by UMN MapServer GDAL UMN MapServer Web Mapping Service (WMS) for visualization Web Feature Service (WFS) for feature data access Web Coverage Service (WCS) for raster data access

12 ADAGUC Web Portal WMS GetMap WMS GetCapabilities WMS GetLegendGraphic WMS GetFeatureInfo

13 Download data from the Portal Download the original file, or convert to your favorite GIS format using OpenGIS Download the original file Raster files are downloaded using WCS Vector files are downloaded using WFS Depending on the datatype, which service is needed? The right service is automatically selected WCS DescribeCoverage WFS MetadataURL WFS or WCS?

14 ADAGUC in GIS programs ArcGIS Explorer gvsig IDV Google Earth ArcGIS Desktop HDF Explorer Quantum GIS UDIG NASA S S Panoply