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ARTEMIS remote terminal connections within FAO headquarters, through dedicated lines, linked to
microcomputers of users, are currently being established in the Emergency Centre for Locust Operations
(ECLO) (IBM) compatible PC with IDA/ILWIS software and VGA/Matrox graphics), the FAO Global
Information and Early Warning System (GIEWS) (IBM Compatible PC with VGA graphics serving a network
of microcomputers with IDA software and EGA graphics capability) and the Centralized Geographic
Information System (GIS) Group (IBM AT with ERDAS/Arclnfo software). Two additional remote terminal
ports to support other in-house users are still available on the present system configuration. In a planned
upgrading of the system, two further remote terminal ports will be added.
(b) Software
The ARTEMIS system software can be divided into the following groups, according to function (van Ingen
Schenau et al. 1986; Hielkema et al. 1986a).
(i) Meteosat PDUS operating system and communications software for controlling data reception,
quality control, quick-look display, data storage and transfer to HP 1000 A900.
(ii) HP 1000 A900 operating system software for operating the computer subsystem and related
peripheral equipment.
(iii) Operational applications software for mapping and thematic processing of Meteosat and NOAA
Global Area Coverage/Local Area Coverage/High Resolution Picture Transmission
(GAC/LAC/HRPT) data and for generation of output products in specific user formats.
(iv) General applications software for image processing for operational and development purposes
(NASA GIMMS software).
(v) Database management and communications software for manipulation and integration of various
ARTEMIS system databases with other data and for retrieval and archival functions.
(vi) Software for definition and extraction of subarea and point data from the ARTEMIS product
database and for archival of raw Meteosat data for point locations.
5. ARTEMIS Data Processing
The ARTEMIS system acquires and processes Meteosat thermal infrared data for rainfall estimation, according
to the TAMSAT methodology of the University of Reading, chronologically as follows (van Ingen Schenau et
al. 1988).
(i) Acquisition and pre-processing of Meteosat digital TIR data for Africa and the Near- East on an
hourly basis through pre-programmed Meteosat PDUS reception schedule and calibration data
as provided by the European Space Operations Centre (ESOC), F.R.G.
(ii) At selected daily intervals, at 21h00 and 03h00, activated by the system clock, transfer of available
digital Meteosat images to central system computer for processing.
(iii) Image selection for rainfall processing programme by using predefined image quality control
parameters.
(iv) Computer maping of selected images to ARTEMIS common geographic format, i.e. Hammer
Aitoff equal area projection and resampling from 5 km input data resolution to 7.6 km
ARTEMIS output product resolution.
