À propos

METLook is a multi functional analysis and interpretation tool devoted to the satellite experiment METEOSAT

Authors: L. Gonzalez ¹, F. Thieuleux ¹
1 Laboratoire d'Optique Atmosphérique, CNRS-USTL1, Villeneuve d'Ascq, France

The authors wish to thank C. Moulin ² for his support
and Anne Marsouin (from Meteo France) for her contribution to the EUMETSAT projection
2 Laboratoire des Sciences du climat et de lenvironnement, CEA-CNRS, 91191 Gif-Sur-Yvette, France

METLook is able to handle the different user format distribution for EUMETSAT's Meteosat programs (MTP, MSG) as OpenMTP rectified images and MSG native or BSQ Level 1.5 format.
The main functionalities offered by METLook are :

• Direct display of images and ancillary data and file header
• Radiometric calibration from MPEF calibration feedback
• Dump of selected data as binary files (either calibrated or raw)
• Basic functions for enhance images, scatter plot, transect and histogram for user-defined areas
• Export images in various format (jpeg), and notably HDF-EOS
• The software allows you to visualize the file values as images using the native projection
• An atmospheric corrected colour composite image using bands 0.67, 0.87, and 1.6 m as blue, green, red is provided, to facilitate the image analysis
• It also performs a tool to reproject images in Sinusoidal projection
• By adding a map directory the user is able to add coat contours and country boundaries to the displayed image
• A communication layer is implemented in the software and can be interfaced with virtually open networked database. Currently, the AERONET database located at LOA and GSFC are accessible and can be called to get for a particular pixel of an image, the aerosol optical thickness or Angström coefficient reported by a network of automounted sun photometers distributed over the globe. Such a functionality allows aerosol users to directly compare their results to AERONET database
• Lastly, a particular effort has always been to produce an efficiency and portable software

This software is a first step to visualize METEOSAT products. Its very simple C and XWindows architecture allows the developpers to add any user useful adding or remark.

Perspectives

First results of this software are promising and future steps to improve this software will be :

• Atmospheric corrections (molecular signal and absorbing gases) applied to images,
• Improvement in RGB image composite,
• Decoding and displaying ISCCP data set product ( AC, B1 and B2 subsampled data ),
• Intercomparison with other platforms (POLDER - MODIS),
• Inclusion of physical methods to retrieve aerosol properties, to compare directly with AERONET network database results.