Andrej Barkhatov - 2014-05-21

MeteosatTool quick start guide

MeteosatTool is a program for visualization and processing of data from Meteosat Second Generation (MSG) geostationary meteorological satellite, and output data of SAFNWC the Satellite application facilities for nowcasting and very short range forecasting software package. Data processing:

  • Satellite images in 12 spectral channels from the MSG sensor
  • The cloud products fields and precipitation product fields computed by SAFNW
  • Geospatial vector data in ESRI shapefile format
  • Bitmap pictures in the common formats JPEG,PNG and others

Due to cross platform GUI (GTK) the program can run on OS Linux and OS Microsoft Windows. Input data specification:

  • The satellite images should be wavelet compressed and decrypted
  • The SAFNWC product fields are HDF5 files
  • The shapefiles (boundaries, shorelines, places, roads and so on) should be in the geographic units (grads or WGS-84)
  • The bitmap pictures should be true color 8 bit per channel

GUI overview
The program GUI consists of the Directory browser, the thematic map Composer, the command Console and the Settings dialog. The directory tree browser is on the left side of the main window. This browser behaves like MS Windows Explorer. Double clicking on a directory shows the list of file names with thumbnails in the middle part of the main window. For the first time, the program produces and caches image thumbnails. The same files access will take much less time. The file list sort order can be changed using the Sort by button on the top bar (the sort order available are by date, by reverse date and by name).

Making the Sochi region precipitation map
Lets make a Sochi (Krasnodar) region precipitation map. The map should be made from three satellite images combined in pseudo color, a precipitation field, a cartographic layer and a color palette for mm/h rain rate. First of all, we should make pseudo color background from the three visible and near infrared images:

  • H-000-MSG3__-MSG3_-IR_016-000007-201401270745-C
  • H-000-MSG3__-MSG3_-VIS006-000007-201401270745-C
  • H-000-MSG3__-MSG3_-VIS008-000007-201401270745-C

To open the files select them in the file list panel of the Dir Browser and click the Open button or double click on a file name (one by one). The first time, this brings up the Settings dialog. This dialog defines XY offsets of the region of interest with regard to the whole satellite image and to a product region (which may be smaller than the whole image). These offsets are measured in pixels so it should be noted that the whole image has 3712 by 3712 pixel size and one image strip has 464 pixel height. But some predefined offsets for well known regions are provided, for example the Sochi region. As we already have Sochi theme selected, we should not touch anything in the dialog (besides the check box Don’t ask again to suppress this dialog box). Then go to the Composer panel.

Pseudo color background is produced from the three spectral channels. We just open the three channels, so click the Make RGB button of the Composer panel. Then we should open the precipitation field file (made by the Convective Rain Rate module of the SAFNWC). Precipitations files should be in HDF5 format for the same time slot. If the check box Don’t ask in the Settings dialog is checked, the precipitation field will be set to the same region as selected on the previous step. The last selected file name, its size and depth are shown at the status bar (bottom line).

Then we can overlay the precipitation field with pseudo color background. A layer selected in the Layers list of the thematic map Composer panel serves as a destination layer for some operations outlined below. To overlay two layers select destination layer (RGB1 layer in our case) and click the Flatten button. In this example we should preserve the source layer (the precipitation field) so we should check Preserve source check box. Then we can print a map with geographical attributes (such as shorelines, roads, railways, places and so on) into this overlay. This map is the PNG bitmap file Sochi.png. The bitmap made from the shape files will be shown below.

Open the file Sochi.png, select the destination layer (RGB1), click Flatten, select the source layer Sochi.png, check Preserve source box.

This is out thematic map of the convective rain rate for 27 Jan 2014 07:45.

The command sequence could be saved into a script (text) file by the Save script button at the command Console and could be executed again in batch mode using the Open Tcl script button.

 

Last edit: Andrej Barkhatov 2014-05-23