Overview
Imports time series data from the Landsat satellite. The files are in HDF5 file format. See the NASA site for information on the files.
Each file contains a single image of one particular meteorological parameter. The following parameters are supported (note: these are the names of the data items in the HDF5 files):
- "LAI"
- " ET" (note the three spaces in front!)
- "ET"
- "FVC"
- "LST"
- "SZA"
- "SC" - snow cover
Configuration (Example)
A complete import module configuration consists of an ID Mapping file and a Import Module Instance file. To convert the rainfall in a proper unit (from 0.01 mm per 3 hour to mm/hr for example) it is also required to configure a Unit Conversion file.
ModuleConfigFiles
The following example of an Import Module Instance will import the time series as equidistant series for timezone GMT with a time step of 6 hours.
<timeSeriesImportRun ......"> <import> <!--Meteo data--> <general> <importType>Landsat-HDF5</importType> <folder>$IMPORT_FOLDER_LANDSAT$</folder> <failedFolder>$IMPORT_FAILED_FOLDER_LANDSAT$</failedFolder> <backupFolder>$IMPORT_BACKUP_FOLDER_LANDSAT$</backupFolder> <idMapId>IdImportLandsat</idMapId> <unitConversionsId>ImportLandsatUnits</unitConversionsId> <!--radar is in GMT--> <importTimeZone> <timeZoneOffset>+00:00</timeZoneOffset> </importTimeZone> <dataFeedId>Landsat</dataFeedId> </general> <timeSeriesSet> <moduleInstanceId>ImportLandsat</moduleInstanceId> <valueType>grid</valueType> <parameterId>Snow-cover</parameterId> <locationId>Landsat-grid</locationId> <timeSeriesType>external historical</timeSeriesType> <timeStep unit="hour" multiplier="3" timeZone="GMT+1"/> <readWriteMode>add originals</readWriteMode> <synchLevel>6</synchLevel> </timeSeriesSet> </import> </timeSeriesImportRun>
IdMapFiles
Defines mappings between Landsat and FEWS parameters and locations.
<idMap version="1.1" ......> <map internalParameter="Snowcover" internalLocation="Landsat-grid" externalParameter="SC" externalLocation="Landsat-grid"/> </idMap>
Grid definition
Defines the definition of the Landsat grid. As not all this information is present in the Landsat files, it needs to be defined in this way.
<?xml version="1.0" encoding="UTF-8"?> <grids ...........> <regular locationId="GridName"> <rows>651</rows> <columns>1701</columns> <geostationarySatelliteView> <centralMeridian>0.0</centralMeridian> </geostationarySatelliteView> <firstCellCenter> <!-- First x must be -COFF*2**16/CFAC, first y must be (NR-LOFF)*2**16/LFAC as found in the HDF5 files Cell sizes must be 2**16/CFAC and 2**16/LFAC --> <x>-1.4796</x> <y>8.6854</y> </firstCellCenter> <xCellSize>0.00480387</xCellSize> <yCellSize>0.00480387</yCellSize> </grids>
Description of the coordinate system:
- The Landsat files contain a set of attributes, of which COFF, LOFF, CFAC and LFAC are the most important ones, as they can be used to determine the coordinate system.
- According to the document http://www.eumetsat.int/groups/cps/documents/document/pdf_cgms_03.pdf, the image coordinates have to be converted to intermediate coordinates x and y that in turn can be converted into longitude and latitude.
- For the Delft-FEWS configuration we need the extremes for x and y (as the satellite image is a rectangle in these coordinates).
- The firstCellCenter's x and y need to be computed
Example Files
See attached files