Whatever the weather in Europe, come rain, storms, snow, sleet or sun, the meteorological satellite, Meteosat-9, will be observing it. Meteosat-9 (Figure 1) is in orbit 36,000 km above the equator from where it gets a space-eye view of weather systems as they develop. The images it transmits down to ground stations every 15 minutes – in the visible light and infrared wavelengths – are used by meteorologists to help produce weather forecasts. While Meteosat-9 stays in one place in relation to the Earth ÛÒ i.e. it is geostationary – it is complemented by another meteorological satellite, Metop-A, which circles closer to the Earth in a polar orbit at 817 km and collects images and more detailed vertical profiles of atmospheric conditions.
Both satellites provide images and atmospheric data that are used by meteorologists to make weather forecasts, and over the longer term they help to monitor changes in the EarthÛªs climate. The good news for researchers, climate modelers, amateur meteorologists, and anyone else wanting to see what Meteosat-9 and Metop-A are observing, is that the data they produce are freely available for non-commercial or research purposes. One option is to access the data via the Internet or, for a relatively small cost, you can even set up your own satellite dish and beam the data collected from Meteosat-9 and other satellites onto the PC in your office or home in near-real time.
Accessing EUMETSAT Satellite Data
The data produced by Meteosat-9 and Metop-A are available from EUMETSAT, EuropeÛªs meteorological satellite agency. EUMETSAT operates Meteosat-9, and its in-orbit backup Meteosat-8 (Figure 2), over Africa to provide weather images for Europe and Africa. The main payload on both of these satellites is the Spinning Enhanced Visible and Infrared Imager (SEVIRI) which builds up images of the Earth’s surface and atmosphere in 12 different wavelengths once every 15 minutes. Regional images, covering smaller areas, can be obtained as frequently as every 5 minutes.
The satellites also carry the Geostationary Earth Radiation Budget (GERB) instrument which provides valuable data on reflected solar radiation and thermal radiation emitted by the Earth and atmosphere.
In addition, EUMETSAT operates two more geostationary satellites – Meteosat-6 and -7 – which are located over the Indian Ocean.
Metop-A, the polar-orbiting satellite, carries a host of instruments – some of the key ones are as follows:
Û¢ The AVHRR (Advanced Very High Resolution Radiometer) scans the Earth’s surface in six spectral bands to provide day and night imaging of land, water and clouds. It also measures sea-surface temperature, ice, snow and vegetation cover.
Û¢ The High Resolution Infrared Radiation Sounder (HIRS) and newer state-of-the-art Infrared Atmospheric Sounding Interferometer (IASI) measure infrared radiation emitted from the surface of the Earth to obtain highly accurate temperature and humidity profiles.
Û¢ The Advanced Microwave Sounding Unit-A (AMSU-A) and Microwave Humidity Sounder (MHS) provide global information on atmospheric temperature and humidity profiles as well as precipitation, even in cloudy areas.
Û¢ GOME-2, (Global Ozone Monitoring Experiment), a spectrometer that is used to derive detailed profiles of the atmospheric content and profile of ozone, nitrogen dioxide, water vapor, oxygen, bromine oxide and other gases.
Û¢ GRAS (Global Navigation Satellite System Receiver for Atmospheric Sounding) – a Global Positioning Satellite (GPS) receiver that provides atmospheric soundings of the temperature and humidity of the EarthÛªs atmosphere.
Û¢ An Advanced Scatterometer (ASCAT) which measures wind speed and direction over the ocean.
EUMETSAT also processes and distributes data from the Jason-2 ocean altimetry satellite which measures ocean surface height and is playing a key role in monitoring sea level rise – a major concern relating to climate change. It also yields valuable information on ocean circulation, surface wind speeds and wave heights.
All EUMETSAT satellites transmit their measurement and telemetry data to receiving stations on the ground. From there, data are relayed to EUMETSATÛªs Control Centre in Darmstadt, Germany, where they are processed, archived in the EUMETSAT Data Centre, and retransmitted in near-real time to the user community, mainly via a system called EUMETCast.
Accessing Data via Eumetcast?
EUMETCast is a data distribution system for high-speed, high-volume data delivery of the EUMETSAT products. It is based on standard Digital Video Broadcast (DVB) technology and uses commercial telecommunication satellites to transmit files (data and products) to a wide user community. There are three broadcasts: Europe in the Ku-band via the Eurobird-9 satellite, Africa in the C-band via the AtlanticBird-3 satellite and North and South America in the C-band via the NewSkies-806 satellite.
The data streams and products delivered via EUMETCast include observations from EUMETSATÛªs Meteosat and Metop satellites, the US National Oceanic and Atmospheric AdministrationÛªs (NOAAÛªs) Geostationary Operational Environmental Satellites (GOES), the Japan Meteorological AgencyÛªs Multifunctional Satellite (MTSAT) and Chinese Fengyun-2 satellites. At their most frequent, these data are delivered to users within five minutes of processing.
Also available via EUMETCast are Moderate Resolution Imaging Spectroradiometer (MODIS) products covering selective geographical regions, numerical weather forecasts, in-situ observational data, land application products covering Europe, Africa and South America, global and regional marine meteorological and ocean surface products, and atmospheric chemistry products.
Set Up Your Own EUMETCast Reception Station?
If you would like to set up your own reception station to receive a EUMETCast data stream, a simple system would need to comprise a standard PC with DVB card inserted and a satellite dish (off-set antenna) fitted with a digital universal V/H LNB.
All components of a EUMETCast reception station are commercially available and as an example, the hardware costs for a single PC station for EUMETCast Europe (Ku-band) reception start at around âÂ1,500. In addition, a EUMETCast client software package is required for handling the incoming DVB and storing it as data files. This package is available directly from EUMETSAT at a one-off cost of âÂ100 per station installation. More information is available on the process of setting up and registering a EUMETCast reception station at: http://www.eumetcast.com
Access to EUMETCast is open to any user within the footprint of one or more of the EUMETCast beams. Once users have equipped themselves with the necessary hardware components, they are invited to register with EUMETSAT in order to gain access to the various EUMETCast data streams. The online registration form is available at https://eoportal.eumetsat.int/Registration/.
Getting Data from the EUMETSAT Data Centre
Another way of accessing meteorological satellite data is via the EUMETSAT Data Centre, which was first established in 1995 and holds an archive of over 25 years of meteorological satellite data and products – one of EuropeÛªs largest and most comprehensive collections in this field.
The range of available EUMETSAT satellite data and products can be searched using the online Product Navigator ÛÒ a central data discovery service which also includes third-party products disseminated via EUMETCast. Users can search for data, subscribe to EUMETCast-disseminated services and, in future, order data via the EUMETSAT Data Centre.
According to Harald Rothfuss, manager of the Data Centre; ÛÏUser access to and orders of EUMETSAT data from the Data Centre are increasing all the time. An average of 50 new users are registering every month to be able to order data from the Data Centre and over 2,500 users are currently registered. As many researchers are now interested in longer time series, for example for climate-related studies, orders in the range of 1 Terabyte (1 TB) are not unusual.Û
ÛÏIn the near future, the process of searching and ordering from the Data Centre will be integrated into the new EUMETSAT Earth Observation (EO) Portal, a project planned to be available during 2010. Interoperability standards implemented in the EO Portal will give users not just a central point where they can manage subscriptions to data, products and services provided by EUMETSAT, it will also allow even more users easy access to EUMETSAT data. The EO Portal with its interoperability standards is an important contribution to various organizations and programs – like the World Meteorological Organization, the Global Earth Observation System of Systems (GEOSS) and the Global Monitoring for Environment and Security (GMES) initiative.Û
When it is finalized, the EO Portal will offer the user community ‘single sign-on’ access to all data services offered by EUMETSAT. In particular, subsequent developments will give users the ability to register and manage their accounts for access to the Data Centre and User Notification Service through the EO Portal user management service. The EO portal can be accessed at https://eoportal.eumetsat.int/
Real-Time Satellite Product Display
A third alternative to accessing the data collected by EUMETSAT weather satellites is to visit the real-time image display section on the EUMETSAT website. There you will find a comprehensive compilation of EUMETSAT satellite products reproduced in graphical form. The service is provided on a 24/7 basis and the image files displayed are automatically refreshed with the latest, openly available data from EUMETSAT satellites. In addition, a limited archive of 100 files per product is provided. The real-time images service incorporates satellite image-data loops, visualized products derived from satellite data and a selection of RGB composite images.
Many Ways to Access EUMETSAT Satellite Data
So to summarize, if you are interested in seeing what meteorological satellites are observing high above the Earth, then there are a number of options: you can visit the EUMETSAT website and see the real-time imagery, you can access archived satellite products at the Data Centre, and you can even set up your own EUMETCast receiving station for weather satellite data, giving you a unique view of what the weather has in store.
Editor’s note: Hyperlinks updated 8-Sept. 2010.