Meteosat Second Generation - System Overvie · EUM TD 07 - Issue 1.1, 25 May 2001 Page III Table of...

MeteosatSecond Generation

System Overview

EUM TD 07

EUM TD 07 Issue 1.1, 25 May 2001

METEOSAT SECOND GENERATIONMSG System Overview

EUM TD 07

Issue 1.1

Meteosat Second GenerationSystem Overview

Page II EUM TD 07 - Issue 1.1, 25 May 2001

Document Change Record

Issue Date ChangeIssue 1.0 18 April 2001 Initial IssueIssue 1.1 25 May 2001 Update to Fig. 4.4


EUM TD 07 - Issue 1.1, 25 May 2001 Page III

Table of Contents

1. PREFACE 1

2. INTRODUCTION 22.1. Scope and Objectives 22.2. EUMETSAT Satellite Programmes 32.2.1. MSG Programme Objectives 42.3. Document Hierarchy 5

3. MSG OPERATIONAL SERVICES 63.1. Image Data Dissemination Service 73.2. Data Collection and Retransmission Service 83.3. Meteorological Data Dissemination Service 93.4. Meteorological Product Extraction and Distribution Service 93.5. Archived Data and Retrieval Service 93.6. Geostationary Earth Radiation Budget Service 103.7. User Support Service 113.7.1. Operational Information 113.7.2. User Service Helpdesk 12

4. MSG SYSTEM DESCRIPTION 134.1. MSG Space Segment 134.1.1. The MSG Satellite 134.1.2. The SEVIRI Radiometer 15

4.1.2.1. Scanning Concept 164.2. The MSG Ground Segment 184.2.1. The Mission Control Centre 19

4.2.1.1. The Central Facility 194.2.1.2. Image Processing Facility 194.2.1.3. Data Acquisition and Dissemination Facility 20

4.2.2. Primary Ground Station 204.2.3. Back-up Satellite Control Centre 224.2.4. Back-up and Ranging Ground Station 224.2.5. Foreign Satellite Data Support 224.2.6. Application Ground Segment 22

4.2.6.1. Meteorological Products Extraction Facility 224.2.6.2. Unified Meteorological Archive and Retrieval Facility 23

4.2.7. Satellite Application Facilities 234.2.7.1. Support of Nowcasting and Very Short Range Forecasting SAF 244.2.7.2. Ocean and Sea Ice SAF 244.2.7.3. Ozone Monitoring SAF 254.2.7.4. Climate Monitoring SAF 264.2.7.5. Numerical Weather Prediction SAF 264.2.7.6. Land Surface Analysis SAF 27

5. ANNEX I COMPARISON BETWEEN MTP AND MSG 295.1. Image Data Generation 295.2. Image Data Dissemination Service 315.3. Foreign Satellite Data Support Service 315.4. Meteorological Data Dissemination Service 315.5. Meteorological Product Extraction and Distribution Service 325.6. Data Collection Service 33


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5.7. Archived Data and Retrieval Service 335.8. User Transition Service 33

6. ANNEX II EUMETSAT DATA POLICY 35

7. LIST OF FIGURES 37

8. LIST OF TABLES 38

9. GLOSSARY OF TERMS 39

10. GLOSSARY OF ACRONYMS 41

EUMETSAT wishes to thank those companies and institutes that have provided illustrations andphotographs for this document but for which a specific acknowledgement has not been possible.


EUM TD 07 - Issue 1.1, 25 May 2001 Page 1

1. PrefaceThis document presents a general introduction to the products, services andfacilities provided by EUMETSAT through the Meteosat Second Generation(MSG) System. It provides an overview of the complete system, focusing onEUMETSAT services and including descriptions of the MSG space and groundsegments.

Like the first series of satellites, the primary service of Meteosat SecondGeneration is the provision to end-users of multi-spectral images of the earth.The acquisition area covers all of Europe, the Middle East, the entire continent ofAfrica, most of the North and South Atlantic oceans and some portions of SouthAmerica (as illustrated in Figure 1.1). However, the Meteosat SecondGeneration system has many improvements over its predecessors and newfeatures, which this document introduces.

This document is complementary to a previous publication, EUM TD 05, thatdescribes the Meteosat system for the Meteosat Transition Programme (MTP). Itincludes a comparison between the services offered by the MTP and the MSGsystems. The transfer phase between the two programmes is also mentioned,albeit briefly, since EUMETSAT Newsletters and information on the EUMETSATWeb Site will address the necessary arrangements comprehensively.

Figure 1.1 A colour-enhanced image of the full earth disk from the first generation Meteosat.Meteosat Second Generation will provide images with the same coverage, but with

significantly improved spectral, temporal and spatial resolution.


Page 2 EUM TD 07 - Issue 1.1, 25 May 2001

2. IntroductionThis chapter recalls the reasons why meteorology and climatology are soimportant to the global economy and the contribution of meteorological satellitesto those disciplines. The EUMETSAT satellite programmes and the specificMSG objectives are described briefly. The document tree for user information isalso included.

2.1. Scope and Objectives

Meteorological satellites have become essential tools for both meteorology andclimatology; they provide vital data for these disciplines at frequent intervals andover wide areas. They continue the two fundamental concepts of data exchangeand international co-operation that have been traditional in these fields for morethan 150 years. International co-operation exists at two levels: First at theEuropean level through those countries which have come together to establishEUMETSAT. The continuity of the Meteosat system enabled through the SecondGeneration ensures the availability of data over nearly one quarter of the planet.The second level of co-operation is on a global scale, which ensures theavailability of satellite data over the entire Earth.

The Meteosat Second Generation system is the latest European contribution tothe global observing system for meteorology and climatology. The primaryobjective of the Meteosat system is to provide cost-effective satellite data andrelated services that meet the requirements of the EUMETSAT Member States.To the greatest extent possible the system also addresses the requirementsexpressed by the World Meteorological Organization (WMO).

The data and services are mainly focused on the requirements of operationalmeteorology, with the emphasis on support to operational weather forecasting.However, the data are of use for all areas of this discipline, including marine,agricultural and aviation meteorology, as well as, for example, climatology andthe monitoring of planet Earth.

Precise and accurate weather forecasts are of much greater importance thantheir use for merely predicting if it will rain or not during the next hours or days.They have become essential for the transport industry to ensure efficient andreliable operations, for the construction and agricultural industries to scheduleactivities that may be affected by weather, and by the retail industry to planstocks of food and clothing for which the demand varies according to theweather. The energy industries also vary the available capacity of their plantsaccording to weather-dependent predictions of demands. Accurate weatherforecasts are therefore a strong contributor to the efficiency of the way in whichmany industries work and therefore a strong contributor to national economies.



The need for climate data also has a strong economic justification. If weatherpatterns change, then agriculture will also change and this may have a profoundeffect, both on individuals and on the economies of nations. If sea levels change,expensive coastal defences may become necessary, or populations may have tomigrate. Where changes are found to be due to human activity, major actionsmay have to be taken to reverse the trends.

The variations in weather and climate have enormous economic consequenceswhich are increasing as the world population grows and becomes moreindustrialised. The need to understand, monitor and predict the weather and thechanging climate is becoming increasingly important.

2.2. EUMETSAT Satellite Programmes

The initial development and early operation of Meteosat was covered by a seriesof ESA programmes. After EUMETSAT was defined in 1983, ESA initiated theMeteosat Operational Programme (MOP), and from 1987 this was conducted asa joint programme, under the overall authority of EUMETSAT. This programmeprovided the framework for the construction and launch of three satellites,Meteosat-4, -5 and -6, as well as the operation of the complete system from 1983until the end of November 1995.

In 1995 EUMETSAT took over the operations of the Meteosat system andimplemented the Meteosat Transition Programme (MTP). This programmeincluded provision and launch of a further satellite of the same design (Meteosat-7), the development of a new ground system, and routine operations fromDecember 1995 until the end of the year 2000. It has since been agreed toextend MTP Operations until at least the end of 2003 to provide an overlap withthe Meteosat Second Generation of satellites (MSG). If technically feasible, itmay be possible to further extend this period of parallel operations, however, thiswill require the approval of the EUMETSAT Council.

Meteosat Second Generation is a significantly enhanced follow-on system to thatoperated under the MTP. It has been designed in response to user requirementsand will serve the needs of nowcasting applications and short range weatherforecasting as well as providing important data for climate monitoring andresearch. The development of Meteosat Second Generation continues thesuccessful co-operation between EUMETSAT and ESA, with two thirds of thecost of the development of the first satellite being funded by ESA. The financialenvelope already approved by the EUMETSAT Council covers the operation ofthree MSG satellites from the year 2002 for more than a decade. Considerationis being given to the manufacture of a fourth satellite in this series.

The lack of observational coverage in parts of the globe, particularly at highlatitudes (North & South), has increased the importance of polar-orbitingsatellites for numerical weather prediction and climate monitoring. The



EUMETSAT Polar System (EPS), now in preparation, is the Europeancomponent of a joint European/US polar satellite system. The Metop-1 satellite,developed in co-operation with ESA and planned for launch at the end of 2005,will carry EUMETSAT and US provided instruments. Later satellites in the serieswill ensure earth observation well into the second decade of the 21st century.

2.2.1. MSG Programme Objectives

The MSG Programme objectives can be summarised by:

1) multi-spectral imaging of the cloud systems, the Earth surface and radianceemitted by the atmosphere, with improved radiometric, spectral, spatial andtemporal resolution when compared with the first generation Meteosat;

2) data collection from data collection platforms (DCP);3) dissemination of the satellite image data and meteorological information to

the user community in a timely manner in support of nowcasting and veryshort range forecasting;

4) extraction of meteorological and geophysical fields from the satellite imagedata in support of general meteorological, climatological and environmentalactivities;

5) user support including the provision of user documents and information, theprovision of a user helpdesk facility and of a service to enable access toarchived MSG image data and products;

6) support to secondary payloads of scientific or pre-operational nature (GERBand Search & Rescue (GEOSAR)) which are not directly relevant to the MSGProgramme. These payloads do not drive the system nor do they interferewith the primary objectives as laid out above under 1) to 5) above.

EUMETSAT will provide the following services to achieve these objectives.

• Image Data Dissemination Service• Data Collection and Retransmission Service• Meteorological Data Dissemination Service• Meteorological Product Extraction and Distribution Service• Archived Data and Retrieval Service• Geostationary Earth Radiation Budget Service

EUMETSAT will provide a comprehensive document set for users wishing tolearn more about the Meteosat Second Generation System and the services thatEUMETSAT will operate to accomplish the mission objectives. Please see thefollowing section for a document hierarchy.



2.3. Document Hierarchy

Figure 2.1 below shows the EUMETSAT technical document set. DocumentsEUM TD 01 - 06 describe the services of the current Meteosat TransitionProgramme (MTP). The series will be extended to cover the entire range ofservices operating under Meteosat Second Generation (MSG). Whilst EUM TD07 “Meteosat Second Generation System Overview” will provide an overview forall products and services available via the MSG system users are encouraged torefer to the documents EUM TD 08 –12 for a more detailed description of theservices and how to access them.

EUM TD 01 Meteorological Data Distribution

EUM TD 02 Meteosat High Resolution Image Dissemination

EUM TD 03 Meteosat WEFAX Dissemination

EUM TD 04 Meteosat Data Collection and Retransmission System

EUM TD 06 Meteosat Archive User Handbook

EUM TD 05 The Meteosat SystemMTP

EUM TD 08 Image Data Dissemination Service

EUM TD 09 Data Collection and Retransmission Service

EUM TD 10 Meteorological Data Dissemination Service

EUM TD 12 Archived Data Retrieval Service

EUM TD 07 Meteosat Second Generation System OverviewMSG

EUM TD 11 Meteorological Product Extraction and Distribution Service

Figure 2.1 User Document Hierarchy



3. MSG Operational ServicesThe primary service provided by the Meteosat Second Generation system is thegeneration of multi-spectral images of the Earth and the transmission of theseimage data to users in the shortest practical time.

In addition there are several other important services as follows:

! The Data Collection & Retransmission Service;

! The Meteorological Data Dissemination Service;

! The Meteorological Product Extraction and Distribution Service;

! The Archive Data and Retrieval Service;

! The GERB Service;

! The User Support Service.

These services are briefly described in the following sections. They are alsodescribed in more detail in the publications EUM TD 08 – 12.

The operational Meteosat satellites are positioned in geostationary orbit, abovethe equator, normally at 0° longitude, i.e. the Greenwich Meridian. From thisposition the satellite is capable of providing images of all of Europe, the MiddleEast, the entire continent of Africa, most of the North and South Atlantic oceansand some portions of South America. Similarly the satellite is able todisseminate these data to users in an extensive area of the globe. Thetelecommunications coverage area for data dissemination and unrestrictedaccess to the services operated by EUMETSAT is illustrated in Figure 3.1. Notethat the 'nominal coverage area' shown includes all the EUMETSAT MemberStates, all of Africa and locations at which the elevation to the satellite is greaterthan or equal to 10°.



Figure 3.1 Meteosat Second Generation Telecommunications nominal coverage area

3.1. Image Data Dissemination Service

The primary payload of the Meteosat Second Generation satellites is theSpinning Enhanced Visible and IR Imager (SEVIRI). The SEVIRI takes basicmulti-spectral imagery with better spectral, spatial and temporal resolution thanthe previous Meteosat satellites. The SEVIRI takes images of the earth,measuring the radiance at 12 different wavebands of the electromagneticspectrum. The various channels provide measurements of different physicalcharacteristics of the atmosphere and the earth at a resolution of 3 km at thesub-satellite point. High resolution imagery is acquired by observing the Earth inthe visible band and sampling at 1 km resolution.

During normal operations the radiometers capture new images of the earth every15 minutes. The earth images and other meteorological data are disseminatedvia the satellite so that information regarding the current meteorologicalconditions may be received by users in as short a time as practical. The MSGsatellites are equipped with transponders to transmit information to user stationslocated anywhere within the field of view of Meteosat. MSG supports twochannels of dissemination via the satellite, the Low Rate InformationTransmission (LRIT) and the High Rate Information Transmission (HRIT).

SEVIRI image data is included in both the LRIT and the HRIT transmissions,however, only HRIT provides the full set of data. The LRIT transmissions includeimage data from other geostationary satellites including the US satellites, GOES-E and GOES-W over the western Atlantic and eastern Pacific, Japan’s GMSsatellite over the western Pacific and the Russian GOMS satellite over the IndianOcean. The LRIT transmission also delivers Meteorological Products from



EUMETSAT and National Meteorological Services, Data Collection Reports, andadministrative messages.

In order to receive image data disseminated via MSG users must be equippedwith suitable High Rate User Stations (HRUS) or Low Rate User Stations (LRUS)depending on their need. The capability to receive the complete set ofdisseminated may be achieved by using an HRUS with a built-in capability toreceive the LRIT stream in addition to the HRIT stream. Generally MSG data willbe encrypted so users will have to acquire decryption units from EUMETSAT inorder to process the received data. For each user requesting one of these unitsan agreement will be concluded reflecting the user’s requirements and in linewith the EUMETSAT Data Policy (see Annex II).

A detailed description of this service may be found in the publication EUM TD 08Image Data and Product Dissemination Service. Further information can also beobtained by contacting the EUMETSAT User Support Service Helpdesk – seesection 3.7.2 for details.

In addition to the direct dissemination via satellite an MSG Internet imagedissemination Service is planned which will provide some of the services formerlyavailable to users from the WEFAX broadcast in MTP operations. Furtherinformation about the content of this service and conditions of access may beobtained from the EUMETSAT Web site.

3.2. Data Collection and Retransmission Service

Data Collection Platforms (DCP) are automatic or semi-automatic environmentalobserving systems. Typical examples are automatic weather stations located atremote sites, automatic river or tide gauges, instrumented aircraft, ships,balloons or buoys. They transmit their environmental data to the MSG satellite,which relays the information to the Primary Ground Station (PGS).

The Meteosat Second Generation system continues the support services for thecollection and relay of Data Collection Platform Messages established with thefirst generation of Meteosat satellites. As a baseline, all basic operatingcharacteristics will generally remain unchanged, however, there is a significantincrease in the capacity of the MSG Data Collection System.

DCP data will be retransmitted via the LRIT dissemination service, via the GTSand also made available via an Internet-based service.

DCP operators wishing to have access to the Data Collection andRetransmission Service should communicate their requirements to EUMETSATusing the User Support Service Helpdesk as their initial point of contact (seesection 3.7.2). Further detailed information about the service may be found inthe publication EUM TD 09 Data Collection and Retransmission Service.



3.3. Meteorological Data Dissemination Service

The MDD Service operating under the MTP will have a similar equivalent in MSGOperations. The MDD data will be included in the LRIT data stream, thus endingthe requirement for a separate user station for the reception of MDD data. Thealphanumeric MDD messages are mainly meteorological reports in conventionalnumeric codes that are suitable for human interpretation but can also be usedwithin computer systems. The binary MDD data are bit-level transmissions foruse within user computer systems to generate charts; the pictorial MDD productsare mainly charts for direct human interpretation. The MDD data relay isconsidered as a space-based extension of the Global TelecommunicationSystem (GTS) of the WMO. Therefore access to these data follows the sameconditions as for the conventional GTS systems, namely access rights areusually only granted to National Meteorological Services. This control isachieved through the means of encryption.

Access to the MDD Service is controlled by the EUMETSAT User SupportService. Further detailed information about the service may be found in thepublication EUM TD 10 Meteorological Data Dissemination Service.

3.4. Meteorological Product Extraction and Distribution Service

The MSG system supports the derivation from imagery of meteorological andclimatological products and their subsequent dissemination to users. This isaccomplished within the Meteorological Products Extraction Facility (MPEF),located within the Mission Control Centre (MCC) in the EUMETSATheadquarters. The MPEF has been designed to allow new products to be addedwhen user requirements have been determined and algorithm development iscompleted. Products are also generated at the Satellite Application Facilities(SAF), and other user facilities.

The products are distributed to users via the GTS (restricted user community)and a subset of products also via the LRIT dissemination service (see section3.1). In addition all products are archived and may be requested by users of theArchived Data Retrieval Service (see section 3.5).

A detailed description of the products available may be found in the publicationEUM TD 11 Meteorological Product Extraction and Distribution Service as well ason the EUMETSAT Web site.

3.5. Archived Data and Retrieval Service

The EUMETSAT data archive is located at the EUMETSAT headquarters inDarmstadt, Germany, and is embodied in the Unified Meteorological Archive and



Retrieval Facility (U-MARF). Its objective is to maintain a permanent archivecontaining all the imagery from the first and second generation Meteosatsatellites as well as from the future EUMETSAT Polar System (EPS). In additionto the imagery, the archive stores all supporting information and centrallyproduced meteorological and climatological products, as well as the SAF productcatalogue.

The U-MARF has been designed to supersede the MARF, which was establishedto support the first generation satellites and has been in operation since 1995.The U-MARF will be available for user access at the start of MSG services in2002. The U-MARF uses new technology to manage the increase in datavolume from the MSG satellites and significantly enhances the services for dataaccess available to users.

A detailed description of the U-MARF and its products and services may befound in the publication EUM TD 12 Archived Data Retrieval Service. In addition,the following dedicated User Support Service Helpdesk point-of-contact exists forall email enquires related to access to archived data: [email protected].

3.6. Geostationary Earth Radiation Budget Service

The MSG system has been designed to support additional or research missions.ESA has, as a result of an Announcement of Opportunity, selected theGeostationary Earth Radiation Budget (GERB) instrument for flight on the MSG-1satellite.

The GERB instrument is being developed by a European consortium led by theRutherford Appleton Laboratory (RAL), United Kingdom, under a co-operationbetween the UK, Italy and Belgium.

The EUMETSAT Council decided in November 1998 to fund the flight of twoadditional GERB instruments on MSG-2 and MSG-3. The principle objective ofthe GERB mission is to measure the Earth radiation budget, in support of climateresearch and monitoring. A GERB International Science Team (GIST) has beenestablished and tasked to define the science requirements, products andprocessing algorithms, and to implement science and validation activities.

The GERB system comprises the GERB instrument and a de-centralised GERBground segment. The GERB instrument is a scanning radiometer with twobroadband channels, one covering the solar spectrum, the other covering theentire electromagnetic spectrum. Data will be calibrated on board in order tosupport the retrieval of radiative fluxes of reflected solar radiation and emittedthermal radiation at the top of the atmosphere with an accuracy of 1%.

The GERB data are received at the EUMETSAT ground segment and passed onto the GERB ground segment for data processing. The data and products arethen distributed by RAL.



The GERB instruments, as part of the satellite, will be operated by EUMETSATin co-ordination with the GERB specialists.

Further details regarding access to the GERB service may be found on theEUMETSAT web site and, as always, enquiries may also be submitted to theUser Support Service Helpdesk (see section 3.7.2).

3.7. User Support Service

The EUMETSAT User Support Service has been established to meet thegrowing demand for information from the users of EUMETSAT satellite data.This Service has key roles providing an effective interface to the services and ahelpdesk facility for the user community, exchanging information with othersatellite operators and providing key contact information for the various satelliteservices (e.g. image dissemination, DCP and MPEF products). In addition theUser Support Service is providing the resources and information necessary tohelp the transition of many thousands of users of data from the MeteosatTransition Programme to the future satellite systems (MSG and EPS) and to co-ordinate and promote user training activities.

Over the years, experience has shown that within the complex environment ofthe Meteosat Programme a considerable number and a wide variety of users’needs have to be fulfilled. This requires a mechanism for effectively gatheringand channelling requests of great variety from the user community as a wholeand to satisfactorily respond to such requests within an acceptable time frame.The user community is, in fact, composed of many different user groups withdiffering needs (e.g. meteorologists, researchers, environmental services,educational establishments, press, media and many others). User enquiriesmight relate to reports of anomalous behaviour of the satellite or its services,more general observations about the system, requests for ancillary information,requests for access to the operational services and the provision of userdocumentation.

3.7.1. Operational Information

Operational information is distributed to users in a variety of ways. The primarysource of information is via the EUMETSAT web site. Administrative messagesare also transmitted within the MSG LRIT and HRIT services to inform usersabout special operations or possible breaks in service, giving as much notice aspossible. In addition, users will, from time to time, receive newsletters that giveup-to-date information about the system and include the latest disseminationbaseline.



3.7.2. User Service Helpdesk

The Helpdesk facility is open to all users to submit their enquiries concerning anyEUMETSAT product or service. The Helpdesk staff is committed to respondingto user enquiries within 3 working days wherever possible and, when internalinvestigations are involved, to fully respond within a maximum of 15 working days(with an interim response supplied within 3 working days). Alternative points ofcontact are provided (see below) for enquiries related to the Archived DataRetrieval Service. The accumulation of the many and varied user enquiriesprocessed over several years of operations has resulted in the establishment ofFrequently Asked Questions (FAQs) and a comprehensive list of these will bemaintained on the EUMETSAT Web site.

The points of contact for the Helpdesk are:

Mail:EUMETSAT User ServiceAm Kavalleriesand 31D - 64295 DarmstadtGermany

Telephone:+49 (0) 6151 807 366 or 377

Fax:+49 (0) 6151 807 304 or 379

E-mail:[email protected] (general enquiries)[email protected] (archive related enquiries)

EUMETSAT Web Site:http://www.eumetsat.de



4. MSG System Description

Figure 4.1 Illustration of the MSG System

The Meteosat Second Generation System provides a comprehensive set ofproducts and services involving the dissemination of information via the satelliteand by other means. The MSG system consists of a space segment and aground segment. It is designed to provide products and services over a lifetimeof at least 12 years, based on a series of three satellites called MSG-1, -2 and -3.The MSG system will perform regular operations with one satellite at the nominallocation at 0º degrees longitude over the equator, and foresees a stand-bysatellite that would be used in case of emergencies or during major configurationchanges.

4.1. MSG Space Segment

4.1.1. The MSG Satellite

The Meteosat Second Generation satellites have been designed to takeadvantage of new technology and to improve on the already successful andproven design of the original Meteosat satellites. The SEVIRI radiometer on-



board the MSG satellite has a total of 12 channels that generate images byscanning the Earth every 15 minutes. The High Resolution Visible channelprovides data at 1km sampling, the other channels sample at 3km. In addition tothe main SEVIRI payload the satellite carries an instrument for the measurementof terrestrial radiation (GERB), telecommunications equipment for thedissemination of processed imagery and products, as well as components for thereception and relay of distress messages for search and rescue (GEOSAR).

The Meteosat Second Generation Satellite is shown in an exploded view inFigure 4.3. The satellite is basically cylindrical with an overall size of 3.7 m indiameter and 2.4 m in height. The MSG spacecraft is composed of three mainsections. The top section contains the mission communications payloadincluding the antennas and transponders required for satellite monitoring andcontrol, down-linking the raw data from the SEVIRI radiometer and GERBinstrument, relay of DCP data, dissemination of LRIT and HRIT information, aswell as the relay of distress signals. The middle section contains the SEVIRIinstrument and it’s associated electronics. The bottom section contains thesatellite propulsion systems and components for the orbit and attitude control.

Figure 4.2 Exploded view of the MSG Satellite



The surface of the satellite is covered with solar cells that provide the electricalpower for operating the satellite, although two rechargeable batteries are alsoavailable and are used during eclipse periods and for peak power demands.

In orbit, viewed from above, the satellite spins at 100 rpm in a counter-clockwisedirection around its main axis, which is aligned nearly parallel to the Earth'snorth-south axis. The spin is required to both stabilise the satellite and to assistin the scanning of the Earth by the SEVIRI radiometer.

4.1.2. The SEVIRI Radiometer

The SEVIRI radiometer is the principal payload of the satellite. It provides thebasic data of the Meteosat Second Generation system, namely 12 channelsspanning the visible and infrared parts of the electromagnetic spectrumsomewhat similar to those of the AVHRR instrument flown on the US NOAAsatellites in polar orbits. There is one high resolution channel, imaging in thevisible region of the spectrum, which can be used to support nowcasting and veryshort-range forecasting applications. There are also seven ‘multi-spectral’imaging channels providing, amongst other information, data about thetemperatures of clouds, land and sea surfaces.

Figure 4.3 Illustration of the SEVIRI instrument



4.1.2.1. Scanning Concept

A series of mirrors within the radiometer direct the radiation originating from theEarth surface, its atmosphere and cloud systems, received via an opening in theside of the satellite, onto an array of detectors. Readings are taken from thedetectors approximately every 24 microseconds as the satellite spins, so that thespin is used to scan the earth in the East-West direction. After every scan line amirror is stepped in the South-North direction in order to acquire subsequentscan lines.

One complete revolution of the satellite lasts 0.6 seconds, of which only about 30milliseconds are available over the Earth disk to acquire one scan. For eachscan step several image lines are acquired (3 lines for nominal channels and 9lines for the high resolution visible channel).

Figure 4.4 Image acquisition by the SEVIRI radiometer

The remaining 570 milliseconds are used mainly for scan mirror stepping, datatransmission and measurements directed at deep space, used for removal ofnoise from the data.

The nominal repeat cycle for a complete scan of the full Earth disk is 15 minutes,this includes measurement of on-board calibration sources and scan mirrorretrace. The satellite can obtain shorter repeat cycles if a reduced area of theEarth is imaged.

The nominal image size for all channels (Level 1.5 image) except for the HighResolution Visible (HRV) is 3712 by 3712 pixels (N-S by E-W), the samplingdistance is defined to be exactly 3km by 3km at the sub-satellite point. For theHRV channel the image size is 11136 by 5568 pixels (N-S by E-W), the samplingdistance defined to be exactly 1km by 1km at the sub-satellite point.



Figure 4.5 HRV Detectors / IR & VNIR Detectors Pixel Acquisition

The scans of data are taken at constant angular steps, and this together with thenatural curvature of the earth means that as the satellite scans away from thesub-satellite point the area covered by the pixels is greater than that at the sub-satellite point. This is illustrated for the multi-spectral channels in Figure 4.6where the respective sizes of pixels are illustrated as a function of their positionon the Earth.

Figure 4.6 SEVIRI multi-spectral image ground resolution (equivalent surface).The bands show the decrease in pixel resolution away from the sub-satellite point.3.1km pixel resolution (inner circle), 4km, 5km, 6km, 8km and 11km (outer band)



4.2. The MSG Ground Segment

The Meteosat Second Generation system has a dedicated ground segment,designed to support all MSG missions and operations over 12 years. The MSGGround Segment is composed of:

• a set of central facilities located at EUMETSAT Headquarters in Darmstadt,Germany, forming the MSG Mission Control Centre (MCC);

• a Primary Ground Station (PGS), located in Usingen, Germany, hostingalso the Back-up Satellite Control Centre (BSCC) and providing theprimary interface between the satellite and the MCC, including all rangingfunctions and communications lines;

• a Back-up and Ranging Ground Station (BRGS), located in Maspalomas,Gran Canaria, Spain;

• Foreign Satellite Data Support (FSDS), located at Météo-France CMCLannion.

• an Application Ground Segment, which extracts meteorological andgeophysical products from the calibrated and geolocated image datagenerated by the MCC. The Applications Ground Segment is composed ofthe Meteorological Product Extraction Facility (MPEF) and the UnifiedMeteorological Archive and Retrieval Facility (U-MARF), both located atEUMETSAT Headquarters, as well as a distributed network of SatelliteApplication Facilities (SAF).

: Numerical Weather Prediction: Climate Monitoring

Meteosat PGSFucino

MDDRoma

Lannion

MDDToulouse

WeilheimMeteosat BGS

Madrid

EUMETSAT HQ DarmstadtMCC + MPEF

BracknellMDD-FDRS

Helsinki

Lisboa

FSDS

Copenhagen

Offenbach

UsingenMSG PGS

Canary IslandMSG BRGS

EUMETSAT Overall Ground Infrastructure

PGS Primary Ground StationMDD Meteorlogical Data DistributionBRGS Back-up and Ranging StationFSDS Foreign Satellite Data SupportCDA Command and Data AcquisitionMCC Mission Control CentreMPEF Met. Product Extraction Facility

EUMETSAT HQCentral Facilities

Acquisition and Control Station

Back-up orSupport Station

Satellite Application Facilityhost site

Madrid (E): Suppport toNowcasting and very Short Term ForecastingLannion (F): Ocean and Sea IceHelsinki (FIN): Ozone MonitoringOffenbach (D)Bracknell (UK)Copenhagen (DK): GRAS MeteorologyLisboa (P): Land Surface Analysis

Figure 4.7 EUMETSAT Overall Ground Infrastructure



4.2.1. The Mission Control Centre

The Mission Control Centre (MCC) is the prime operations centre and isresponsible for the monitoring and control of the main components of the MSGsystem, including the spacecraft, the telecommunication elements and most ofthe ground segment. It is located in the Operations wing of the EUMETSATheadquarters building in Darmstadt, Germany. The MCC is thus the core of theMeteosat ground segment. Dedicated communications links connect it to thePrimary Ground Station. The MCC itself is composed of a number of facilities.

4.2.1.1. The Central Facility

The Central Facility of the Mission Control Centre provides the essential controlinfrastructure for the satellite and the ground segment. This includes theplanning, scheduling and execution of activities and the centralised monitoringand control of all components. The facility is highly automated in several areasto ease daily operations. The facility is responsible for the central configurationand control of software and databases that operate in the MCC. It is alsoresponsible for local archiving and providing the means for the analysis ofoperational data (e.g. monitoring or housekeeping data from the ground segmentand the satellite).

The basis for all activity within the system is the operations plan. This governsthe routine cycle of operations and is monitored using Central Facility consoles.Routine spacecraft commands are stored in the computer system andtransmitted automatically in accordance with a pre-defined schedule. Non-routine commands are transmitted in accordance with pre-defined procedures.The transmission of the command sequences and the telemetry from thespacecraft are all displayed on the consoles. Many hundreds of parameters aremonitored for each spacecraft.

The configuration of the spacecraft and the ground segment can also be shownon the consoles, with displays showing which of the redundant components arein active use and which are available in stand-by mode. The system permitsreconfiguration of both the spacecraft and the ground station under softwarecontrol from the consoles. This includes the facility for remote operation andcontrol of the Primary Ground Station and the Back-up ground station.

4.2.1.2. Image Processing Facility

Raw images are received from the Primary Ground Station and processed line-by-line in the Image Processing Facility (IMPF) to generate Level 1.5 image data.Re-sampling realigns the data from the various on-board sensors so that theimage from each set of detectors coincides with the other images. At the same



time, the sampling removes any slight perturbations caused by the movement ofthe spacecraft, thereby rectifying the image so that it appears to come from thenominal location of the spacecraft. The data are then adjusted according tocertain calibration information. The IMPF is also responsible for the automaticradiometric and geometric quality assessment of the data. The image is passedin segments from the IMPF to the dissemination facility for immediate relay tousers, to the Meteorological Product Extraction Facility (MPEF) for furtherprocessing and to the U-MARF for archiving.

4.2.1.3. Data Acquisition and Dissemination Facility

The Data Acquisition and Dissemination Facility (DADF) collects together thevarious types of data required for dissemination through the satellite via the LowRate Information Transmission (LRIT) and High Rate Information Transmission(HRIT) services. This includes the pre-processed imagery from the IMPF,meteorological products from the MPEF, DCP data, and foreign satellite datafrom the Support Ground Segment. The data are formatted and prioritised fortransmission. Depending on the type of data the formatting may includecompression and encryption.

The facility also contains four user-monitoring stations for the reception of allLRIT and HRIT data transmissions from the satellites. These stations are usedto implement a full end-to-end monitoring of the performance of thedissemination. Thus the system operators can, at any stage, be alerted to anyproblem in the complete system and take immediate action to rectify thesituation.

The Data Collection messages are also monitored within the DADF. Messagesfrom DCPs are received in the Primary Ground Station from the MeteosatSecond Generation satellite and transmitted immediately to the MCC inDarmstadt. There they are compared with the master list of expected DCPreports and processed and distributed as appropriate. This operation isperformed entirely automatically.

4.2.2. Primary Ground Station

The MSG Primary Ground Station (PGS) is located in Usingen, Germany. It is afacility fully owned by EUMETSAT, within a commercially operated siteapproximately 30 km north of Frankfurt.

The PGS serves as the main channel of communications with the MSG satellitesand is an essential component of the overall system. The prime transmissionchannel between the MCC and the PGS is a 34 Mbit Microwave link with aterrestrial based back-up link. These links support all the traffic to and from thePGS including image data, TT&C and disseminated data.



To reliably accomplish these vital tasks a considerable amount of redundancy isincorporated in the station design which, to a great extent, can functioncompletely automatically.

Two fully steerable 13-metre diameter parabolic antennas are located at the PGSand used exclusively to support all communications with MSG. Each antenna iscapable of supporting all the transmissions and data reception required for onespacecraft and is used for telemetry and telecommands, raw image reception,DCP report collection, LRIT and HRIT dissemination.

Figure 4.8 A MSG 13 metre antenna at the PGS at Usingen, Germany.

The control of the PGS is actually executed by a local monitoring and controlsystem located in Usingen and interacting with the MCC in Darmstadt. The PGScan operate in two different modes: remotely, under the control of the MCC, orthrough the use of the local system consoles. This flexibility ensures maximumreliability in case of problems.



4.2.3. Back-up Satellite Control Centre

Also located at the PGS is a Back-up Satellite Control Centre (BSCC). This isestablished as a functional extension of the MCC in Darmstadt so that in anextreme emergency it could be used in a stand-alone mode to monitor andcontrol the spacecraft and the PGS, as well as to perform all essential flightactivities. It is not designed to support the user services but does ensure thesafety of the spacecraft until any problem is solved.

4.2.4. Back-up and Ranging Ground Station

The Back-up and Ranging Ground Station (BRGS) is located in Maspalomas,Gran Canaria, Spain. This location is sufficiently separated from the PGS toallow accurate ranging measurements to be made to determine the preciselocation and orbit of the MSG satellites.

The BRGS also provides TT&C support to the Ground System so that in theunlikely event of a complete system failure at the PGS it would still be possible tosafeguard the spacecraft in orbit. However, in this scenario mission control anduser services would not be operable.

4.2.5. Foreign Satellite Data Support

The satellite ground station facilities owned and operated by the Frenchmeteorological service in Lannion have been associated with the Meteosatsystem since the start of operations in 1977. EUMETSAT provides andmaintains facilities at Lannion for the relay of image data from additionalsatellites, to complement the Meteosat images transmitted from the PGS. Theprimary requirement is to relay images covering the western part of the Atlanticand the Americas. These images are obtained from GOES-E, GOES-W, GOMSand GMS. MSG will continue to carry that mission through its data disseminationand aims at an expansion of the current service to meet the requirement of theGlobal Observing System (GOS) to provide a near global data coverage severaltimes a day.

4.2.6. Application Ground Segment

4.2.6.1. Meteorological Products Extraction Facility

The Meteorological Products Extraction Facility (MPEF) is co-located with theMission Control Centre and comprises another network of dedicatedworkstations, which receive pre-processed images from the IMPF and process



them, together with ancillary data, to extract quantitative meteorological andclimatological products. The MPEF also is responsible for monitoring the qualityof the products (by comparison with independent observations) and of imagedata calibration. Image display and analysis tools allow the operators to monitorthe progress of the automatic processing of the image data.

4.2.6.2. Unified Meteorological Archive and Retrieval Facility

The Unified Meteorological Archive and Retrieval Facility (U-MARF) is also co-located at the MCC. The U-MARF provides the users with a non-real timeretrieval capability for all of the imagery and meteorological products owned byEUMETSAT. This includes the data from the Meteosat Operation Programme,Meteosat Transition Programme, Meteosat Second Generation and the futureEUMETSAT Polar System. The U-MARF uses modern tape recordingtechnology to store the data in a robotic archive system. The retrieval will bepossible either via a Web-based on-line interface to the system or off-line via theHelpdesk facility. Retrieved data may also be shipped on-line (via the Internet)or off-line (using electronic media).

4.2.7. Satellite Application Facilities

A network of Satellite Application Facilities (SAFs) is included in the MSGGround Segment. These SAFs are under the overall co-ordination ofEUMETSAT and have the remit to develop and deliver products (or software toderive products), extracting geophysical parameters primarily from MSG andEPS satellite data. The SAFs are generally located in National MeteorologicalServices or other approved institutes of a EUMETSAT Member State. Byutilising the specialised expertise of the Member States the SAFs complementthe production of standard meteorological products derived from satellite data atEUMETSAT’s MCC. This will promote and ensure the optimum use of data fromthe MSG and EPS systems in their application domain.

Seven SAFs have been approved and are under development. Each SAFconcentrates on a different theme.

Details of each SAF are outlined in the following text. Further information can befound by contact the SAFs through their web sites (URL provided at the end ofeach section). Information about SAF products is included in the U-MARFcatalogue. Access to the products in non-real-time is supported by the U-MARFuser interface.



4.2.7.1. Support of Nowcasting and Very Short Range Forecasting SAF

Nowcasting and very short range forecasting combine the continuous monitoringof meteorological conditions on a horizontal scale of tens to hundreds ofkilometres, with the prediction of their development over the next two or threehours. This includes the monitoring of short-lived, but disruptive weatherphenomena such as severe thunderstorms or fog.

Under the leadership of the Spanish Meteorological Institute (INM), the NWCSAF is developed by a project team involving Météo-France and the Swedishand Austrian Meteorological Institutes.

The list of products developed by the NWC SAF is as follows:

• Cloud mask and cloud amount

• Cloud type (including fog)

• Cloud top temperature / height

• Precipitating clouds

• Convective rainfall rate

• Total precipitable water

• Layer precipitable water

• Stability analysis imagery

• High resolution wind vectors from HRVIS

• Automatic satellite image interpretation

• Rapidly developing thunderstorms

• Air mass analysis

The NWC SAF Web pages are located at:

http://www.inm.es/wwg

4.2.7.2. Ocean and Sea Ice SAF

The Ocean and Sea Ice (OSI) SAF was established to develop a range ofproducts relating to oceans and sea ice, using satellite data as the primary input.These products will provide information for a diverse set of users, including thosein numerical weather prediction, climate monitoring, transport, the fishingindustry, ecology, pollution monitoring, coastal engineering and the offshore oiland gas industry.



The SAF is developed by a consortium, led by Météo-France, and involving theMeteorological Institutes from Norway, Denmark, Sweden and the Netherlands,as well as the French institute for Oceanography.

The main objective of the OSI SAF will be the routine production and archive of acoherent set of information characterising the ocean surface and energy fluxesthrough it. Three scales of application will be considered:

• Atlantic Ocean and adjacent coastlines

• Regional (north-east and European seas)

• Polar seas

The products to be produced by the OSI SAF include:

• Surface wind vectors (global)

• Atlantic sea surface temperatures

• Atlantic surface radiative fluxes

• Regional sea surface temperature

• Atlantic sea ice edge

• Atlantic sea ice cover

• Atlantic sea ice type

The OSI SAF Web pages are located at:

http://www.meteorologie.eu.org/safo

4.2.7.3. Ozone Monitoring SAF

The Ozone monitoring (O3M) SAF has been developed to process data onozone distribution, other trace gases, aerosols and ultraviolet data. The severeloss of stratospheric ozone in the high latitudes of the Northern Hemisphere andover the Antarctic and the subsequent increase of harmful ultraviolet radiationhas been well established in various measurements. Ozone data are alsoimportant for climate research and as input to numerical weather prediction.Trace gas measurements are important for monitoring the long-term effects of,for example, freons and halons on the ozone layer.

The O3M SAF involves nine institutes from seven countries (Finland,Netherlands, Germany, Greece, Denmark, France, and Belgium) and is led bythe Finnish Meteorological Institute (FMI).

The O3M SAF is responsible for research and development in radiative transfercalculation methods and other algorithms for obtaining ozone products from



satellite data. Data from the EPS mission (GOME-2 instrument) will be the maininput data for this SAF. The SAF will provide data for ultraviolet fields under realatmospheric conditions, total ozone, ozone profiles, aerosols and total amountsof chemically important gases such as: nitrogen dioxide, chlorine dioxide,bromine oxide, as well as stratospheric aerosols.

The O3M SAF Web pages are located at:

http://www.ozone.fmi.fi/o3group/o3saf.html

4.2.7.4. Climate Monitoring SAF

The CLM SAF for climate monitoring has been established to generate andarchive high quality data sets from satellite observations, essential for themonitoring of the global climate. These data sets will assist in the analysis anddiagnosis of climate parameters to identify and understand changes in theclimate system.

The CLM SAF involves ten institutes from five countries: Belgium, Finland, TheNetherlands, Sweden and Germany. The German Meteorological Institute(DWD) leads the project team.

The deliverables of the SAF will be:

• Cloud data: fractional cloud cover, cloud classification, cloud toptemperatures and height, cloud phase, optical thickness and cloud water path

• Components of the surface radiation budget: solar surface irradiance andalbedo as core products

• Components of the radiation budget at the top of the atmosphere

• Homogeneous data sets of SST and sea ice cover

• Water Vapour layer information

The CLM SAF Web pages are located at:

http://www.dwd.de/research/saf

4.2.7.5. Numerical Weather Prediction SAF

Numerical Weather Prediction (NWP) involves the use of powerful computers tomodel the atmosphere and compute forecasts extending from a few hours up toten days. NWP is a central facility of the National Meteorological Services,crucial to the quality of their forecasting services. Observational data are thebasis of NWP, and satellite information is an important element.



The NWP SAF consortium is led by the Meteorological Office (UK) and involvesthe National Meteorological Services from France and the Netherlands, as wellas, the European Centre for Medium Range Weather Forecasts (ECMWF).

The SAF will concentrate on developing techniques for more effective use ofsatellite data in NWP, in particular, exploiting the data and derived products fromnew satellite systems. This will involve the retrieval of geophysical parametersfor integration as pseudo-observations by NWP. It will define the most effectiveinterface between satellite data and NWP data assimilation systems. This willlead eventually to improved estimates of temperature, humidity, wind (bothsurface and upper air) and ozone.

Concerning data from MSG, the SAF will work on improved observationoperators for satellite winds, including radiative transfer models required fordirect assimilation of time sequences of radiances from geostationary imagery.

The NWP SAF Web pages are located at:

http://www.met-office.gov.uk/sec5/NWP/NWPSAF

4.2.7.6. Land Surface Analysis SAF

Information about the land surface is essential for Numerical Weather Prediction,monitoring of the environment and climate change, agriculture and forestry.

Many human activities benefit from increased information about the land surface.Examples are the monitoring and prediction of drought, crop yields and quality,forests and the mapping of vegetation.

The LSA SAF involves thirteen institutes from eight countries (Portugal, France,Germany, Greece, Italy, Spain, Sweden, and Belgium) and is led by thePortuguese Meteorological Institute (IM).

The LSA SAF will concentrate on developing techniques for deriving land surfaceparameters and radiation surface fluxes over the continents from the dataprovided by EUMETSAT’s satellites. The land surface data will benefit otherSAFs in addition to National Meteorological Services, and government andinternational agencies concerned with agriculture and forestry.

The LSA SAF will produce the following products:

• Surface albedo

• Aerosols

• Scattered radiance field

• Down-welling surface short wave and long wave radiation fluxes



• Land surface temperature

• Soil moisture

• Snow cover and mapping

• Evapotranspiration rate

• Vegetation parameters (Normalised Differential Vegetation Index (NDVI),Fraction of Green Vegetation (FGV), fraction of Photosynthetic Radiation(fPAR) and Leaf Area Index (LAI))

The LSA SAF Web pages are located at:

http://www.meteo.pt/landsaf



5. Annex I Comparison between MTP and MSGThe Meteosat Second Generation system will continue to provide the operationalservices required by National Meteorological Services and other users that wereestablished with the so-called MOP and MTP satellite series. However, due tomore demanding user requirements and improvements in technology there havebeen changes in the implementation of these services. It is important for existingusers of the MTP system to understand the differences.

5.1. Image Data Generation

The image rectification and dissemination service of the Meteosat SecondGeneration satellite significantly improves on the capabilities of the MTP. Theradiometer on-board the MSG satellite has a total of 12 imaging channels insteadof the three on the original Meteosat satellites. Images are generated every 15minutes instead of every 30 minutes. The sampling distance of the infraredchannels (at the sub-satellite point) is improved to 3km compared with 4.5km,while the new High Resolution Visible channel provides 1km instead of theprevious 2.25km sampling distance.

Figure 5.1 A side-by-side comparison of the Meteosat First and Second Generation satellites

The MSG satellite is again spin-stabilised, rotating at 100 Revolutions Per Minute(RPM), and with an increased body weight of 2000kg in GTO orbit compared tothe 720kg of the previous Meteosat satellites. The MSG satellite has a powerdemand three times that of the previous Meteosat satellites, 600Watts comparedto 200Watts. In spite of this, the MSG satellite has been designed with a station-



keeping lifetime of 7 years, 2 years longer than that of the first generationMeteosat satellites. The single imaging radiometer concept known as SEVIRI,allows the simultaneous operation of all the radiometer channels with the samesampling distance. Thus, it provides improved image accuracy and productssuch as atmospheric motion vectors or surface temperatures and also new typesof information on atmospheric stability.

MOP / MSG PERFORMANCE EVOLUTION 1st Generation 2nd Generation

Imaging Format

Imaging Cycle 30 min 15 minWavelength

Visible 0.5-0.9

HRVVIS 0.6VIS 0.8IR 1.6

Water Vapour WV 6.4 WV 6.2WV 7.3

IR Window

IR 11.5

IR 3.9IR 8.7

IR 10.8IR 12.0

Cha

nnel

s

Air massAnalysis

IR 9.7 + WVIR 13.4

Sampling Distance 2.25 km (visible)4.5 km (IR + WV)

1 km (HRV)3 km (others)

Pixel Size

(MTP Square-shapedcompared to MSGdiamond-shaped)

2.25 km (visible)

5 km (IR + WV)

Number ofDetectors

4 42

TelescopeDiameter

400 mm 500 mm

Scan Principle Scanning telescope Scan mirror

Table 5.1 MOP to MSG Performance Evolution



5.2. Image Data Dissemination Service

DATA TRANSMISSION RATESMOP MSG

Transmission rawdata rate

0.333 Mbs 3.2 Mbs

Disseminatedimage

0.166 Mbs 1 Mbs (HRIT) and128 Kbs (LRIT)

Table 5.2 MOP to MSG Performance Evolution

The capabilities for data transmission from the MSG satellite have beenimproved to be able to disseminate the significantly increased amount ofinformation gathered by the satellite. The LRIT and HRIT services replace theHigh Resolution Image (HRI) and WEFAX dissemination services of the MTP.The change to the new LRIT and HRIT service means that users will need newuser stations for MSG data reception. However, it is possible that the antennaand some other components of existing MDD or PDUS systems may be reusablefor LRIT reception stations.

Additionally, an MSG Internet Service is planned which will provide some of theservices formerly available from the WEFAX broadcast.

5.3. Foreign Satellite Data Support Service

The global observing system of meteorological satellites, with nominal locationsagreed between the satellite operators and WMO within the Co-ordination Groupof Meteorological Satellites (CGMS), consists of the following five spacecraft:Meteosat (Europe) at 0°E, GOMS (Russia) at 76°E, GMS (Japan) at 140°E,GOES East (USA) at 75°W, GOES West (USA) at 135°W. The data of INSAT(India) at 93°E, a national satellite of India, may also become available to themeteorological community in the future.

The facilities of CMS, Lannion (France) are used for gathering the foreignsatellite data rebroadcast via the Meteosat satellites. The Meteosat systemprovides a relay of data from GOES-E, GOES-W, GOMS and GMS data in theWEFAX and HRI broadcasts. MSG will continue this service and foreign satellitedata will be included in the LRIT data stream.

5.4. Meteorological Data Dissemination Service

The Meteorological Data Distribution (MDD) service of the MTP will be continuedwith MSG with MDD data being included in the LRIT data stream, thus ending



the requirement for a separate user station for the reception of MDD data. Anidentical set of MDD data will be disseminated, taking the form of WMOalphanumeric bulletins, WMO binary coded bulletins, or pictorial products.

The Meteorological Data Distribution (MDD) service is a service providingmeteorological data to areas of the world, within the view of the Meteosatsatellite, which are without reliable conventional communications. In particular, itallows countries in Africa to receive observations, analyses and forecasts frommajor meteorological centres that would otherwise be nearly impossible toreceive.

The first generation Meteosat MDD system used dedicated transmissionchannels to transmit data from three data up-link sites located at meteorologicalcentres in Bracknell (UK), Rome (Italy) and Toulouse (France).

The first generation Meteosat system disseminates data to MDD user terminals,which may be located at meteorological centres at any point within the satellitetelecommunications field of view. The actual terminal is quite simple andconsists mainly of a small parabolic antenna, a receiver, a personal computer (orworkstation) and a printer. The computer can be used to display alphanumericmessages or convert these data into graphical displays. It can also be used toprocess and display the binary data and display the pictorial information. Sinceall MDD transmissions are encrypted, a Meteosat Key Unit (MKU) is also a vitalpart of the MDD terminal and is used to decrypt the data. Since only NationalMeteorological Services are allowed access to MDD data, they have to obtain theMKU directly from EUMETSAT.

5.5. Meteorological Product Extraction and Distribution Service

During MTP operations a number of products (e.g. Cloud Motion Winds) havebeen produced in a routine fashion. In the Meteosat Second Generation systemalso a variety of products is produced to ensure the continuity of the space-basedobservations in an enhanced manner (see chapter 3.4). These products will becomplemented by products derived at the Satellite Application Facilities (SAF)which are centres of excellence located in a National Meteorological Service orother approved institutes of EUMETSAT Member States. These centres aregenerally dedicated to the study of different thematic areas associated withmeteorology and climatology.

For MTP the dissemination method for these products was primarily the GTS andthey were also archived in the MARF. For MSG the GTS will also be used, theproducts will be stored in the U-MARF and a subset of them will be disseminatedas part of the LRIT service.



5.6. Data Collection Service

The DCP Service is also significantly improved in the Meteosat SecondGeneration system. The number of regional channels used to receive reportsfrom DCPs has been increased from 33 to 223, and 33 international channels willbe retained for global relay of DCP messages.

These changes may require some DCP operators to alter the transmittingfrequency of their DCP. There may also be a need to re-certify certain designs ofDCP before they can be allowed to operate with MSG. For information regardingthe certification of new and existing Data Collection Platforms into the MSGsystem refer to TD09 “Data Collection and Retransmission (DCS) Service”.Furthermore, considering that Meteosat-7 will be located close to 10ºW duringthe period of parallel MTP/MSG operations, the area of reception coverage willnot be as it is from zero degrees longitude. EUMETSAT is working closely withthe DCP operators to co-ordinate any changes that may be required.

The DCP reports are also disseminated via the LRIT dissemination service;consequently this will end the need for a separate user station to receive DCPmessages.

5.7. Archived Data and Retrieval Service

The U-MARF, will provide a permanent store for all images and meteorologicaldata at EUMETSAT. The previously named archive facility, MARF, housing theMOP and MTP data, will be incorporated with data from MSG and theEUMETSAT Polar System (EPS) in a standard format. The U-MARF alsoincludes an on-line User Interface through which access to all data is enabled.

From the U-MARF user perspective, the transition from MTP to MSG Operations,and beyond, should be almost seamless with the only noticeable changes beingthe evolution of the on-line user interface and enhancements to the service.

5.8. User Transition Service

To ease the transition of users from MTP to MSG the EUMETSAT Council hasagreed to continue the MTP services until at least the end of 2003. Meteosat-7will be moved to a new orbital position close to 10ºW in order to prevent anyinterference with the MSG service. Therefore, users who wish to continue usingthe MTP dissemination services will need to re-point their user-station antennasin order to continue reception.

The EUMETSAT User Support Service is undertaking a number of steps toinform users of these changes. A series of Technical Documents describe thenew services in detail. Newsletters and the EUMETSAT Web Site also provide



up-to-date information to keep users informed of the changes and theirtimetables. More information can be obtained from the EUMETSAT UserSupport Service, please refer to section 3.7 for contact details.

Mapping of Services from MTP to MSGService MTP MSGImage Data DisseminationService

HRI / WEFAXInternet

LRIT / HRITInternet

Meteorological DataDissemination Service

Dedicated transmissionchannels to transmit data from3 up-link sites

LRIT

Meteorological ProductExtraction and DistributionService

GTSDistributed via WEFAX (oneproduct only)

LRITGTS

Data Collection andRetransmission Service

DRS (Channel A1 1691 MHz)GTSInternet

LRITGTSInternet

Foreign Satellite Data SupportService

HRI / WEFAXInternet

LRITInternet

Archived Data and RetrievalService

MARF U-MARF

GERB Service Not available To be announcedGEOSAR Not available Relay distress signals of

406MHz beaconsUser Support Service EUMETSAT

InternetEUMETSATInternet

Table 5.3 Mapping of Services from MTP to MSG



6. Annex II EUMETSAT Data PolicyThe products and services from Meteosat and other EUMETSAT meteorologicalsatellites are made available to a wide user community. Access and use aresubject to terms and conditions set by the EUMETSAT Council.

The Council has decided that some products are available on a free andunrestricted basis as "essential" data in the sense of Resolution 40 (Cg-XII) ofthe World Meteorological Organization (WMO). For products that do not fall inthis category measures exist to control user access. For those disseminated viathe LRIT and HRIT service the transmissions are encrypted and a special devicecalled a Station Key Unit (SKU) for MSG and EPS data, (MKU) for MTP data, isrequired to decode the broadcasts. Some services are granted subject to theconclusion of a licence agreement.

The main principles of the Data Policy are as follows:

1. NMSs of the EUMETSAT Member States and Co-operating states receive allproducts and services for their Official Duty Use free of charge;

2. In the EUMETSAT Member States and Co-operating states, the NMSs act asEUMETSAT's agents for the purpose of granting access to real-time data. Incase of commercial use, equal conditions apply to NMSs and non-governmental organisations;

3. Outside the EUMETSAT Member States and when dealing with internationalorganisations, EUMETSAT is the direct licensing authority for products andservices. Both within and outside Member States EUMETSAT is responsiblefor supplying archived products and for granting access to the satellites'telecommunications channels;

4. As stated above, "essential" data in the sense of WMO Resolution 40 areavailable free of charge to all users world wide;

5. A further subset of products and services is available for NMSs of non-Member States for official duty use free of charge;

6. A subset of products and services is available free of charge for non-commercial research projects and educational use;

7. Use of EUMETSAT products and services for other purposes than thoselisted above is subject to certain terms and conditions, possibly including thepayment of fees.

These Data Policy Principles apply to all products and services generated by theEUMETSAT meteorological satellites. Their detailed implementation can, ofcourse, vary according to the particular type of product or service to which theyare being applied.



Further details are available on the EUMETSAT Web site athttp://www.eumetsat.de and through the contact address provided in section 3.7.



7. List of FiguresFigure 1.1 A colour-enhanced image of the full earth disk from the first

generation Meteosat. Meteosat Second Generation will provideimages with the same coverage, but with significantly improvedspectral, temporal and spatial resolution..................................... 1

Figure 2.1 User Document Hierarchy........................................................... 5Figure 4.1 Illustration of the MSG System.................................................. 13Figure 4.2 Exploded view of the MSG Satellite .......................................... 14Figure 4.3 Illustration of the SEVIRI instrument ......................................... 15Figure 4.4 Image acquisition by the SEVIRI radiometer ............................ 16Figure 4.5 HRV Detectors / IR & VNIR Detectors Pixel Acquisition ........... 17Figure 4.6 SEVIRI multi-spectral image ground resolution (equivalent

surface)..................................................................................... 17Figure 4.7 EUMETSAT Overall Ground Infrastructure ............................... 18Figure 4.8 A MSG 13 metre antenna at the PGS at Usingen, Germany. ... 21Figure 5.1 A side-by-side comparison of the Meteosat First and Second

Generation satellites ................................................................. 29



8. List of TablesTable 5.1 MOP to MSG Performance Evolution ....................................... 30Table 5.2 MOP to MSG Performance Evolution ....................................... 31Table 5.3 Mapping of Services from MTP to MSG.................................... 34



9. Glossary of TermsAdvanced VeryHighResolutionRadiometer(AVHRR)

Cross-track multi-spectral scanner on a NOAA polar-orbiting satellite thatacquires five spectral bands of data (0.55 to 12.50 µm) with a groundresolution cell of 1.1km by 1.1km.

Antenna A device that transmits and receives microwave and radio energy.

Band A wavelength interval in the electromagnetic spectrum.

Beam A focused pulse of energy.

Bit Contraction of binary digit, which in digital computing represents anexponent of the base 2.

Blackbody An ideal substance that absorbs all the radiant energy incident on it andemits radiant energy at the maximum possible rate per unit area at eachwavelength for any given temperature. No actual substance is a trueblackbody, although some substances, such as lampblack, approach itsproperties.

Byte A group of eight bits of digital data.

Calibration Process of comparing an instrument’s measurements with a standard.

Detector Component of a remote sensing system that converts electromagneticradiation into a recorded signal.

Digital number(DN)

Value assigned to a pixel in a digital image.

Electro-magneticradiation

Energy propagated in the form of an advancing interaction between electricand magnetic fields. All electromagnetic radiation moves at the speed oflight.

Electro-magneticspectrum

Continuing sequence of electromagnetic energy arranged according towavelength or frequency.

Emission Process by which a body radiates electromagnetic energy. Kinetictemperature and emissivity determine emission.

Frequency Number of wave oscillations per unit time or the number of wavelengthsthat pass a point per unit time.

Geometriccorrection

Image-processing procedure that corrects spatial distortions in an image.

Geostationary Refers to satellites travelling at the angular velocity at which the earthrotates; as a result, they remain above the same point on earth at all times.

Image Pictorial representation of a scene recorded by a remote sensing system.

IR Infrared region of the electromagnetic spectrum that includes wavelengthsfrom 0.7µm to 1mm.

Multi-spectralscanner

Scanner system that simultaneously acquires images of the same scene atdifferent wavelengths.

Nadir Point on the ground directly in line with the satellite and the centre of theearth.



Noise Random or repetitive events that obscure or interfere with the desiredinformation.

Orbit Path of a satellite around a body such as the earth, under the influence ofgravity.

Picture element In a digitised image, the area on the ground represented by each digitalnumber. Commonly contracted to pixel.

Radiant flux Rate of flow of electromagnetic radiation measured in watts per squarecentimetre.

Radiation Propagation of energy in the form of electromagnetic waves.

Radiometer Device for quantitatively measuring radiant energy.

Reflectance Ratio of the radiant energy reflected by a body to the energy incident on it.Spectral reflectance is the reflectance measured within a specificwavelength interval.

Resolution Ability to separate closely spaced objects on an image. Resolution iscommonly expressed as the most closely spaced line-pairs per unitdistance that can be distinguished. Also called spatial resolution

Satellite An object in orbit around a celestial body.

Scan line Narrow strip on the ground that is swept by a detector in a scanningsystem.

Scanner An imaging system in which the field of view of one or more detectors isswept across the terrain.

Sensor Device that receives electromagnetic radiation and converts it into a signalthat can be recorded and displayed as either numerical data or an image.

Telemeter To transmit data by radio or microwave links.

Transponder A radio or radar receiver-transmitter activated for transmission by receptionof a pre-determined signal.

Visibleradiation

Energy at wavelengths from 0.4 to 0.7µm that is detectable by the humaneye.

Wavelength (!!!!) Distance between successive wave crests or other equivalent points in aharmonic wave.



10. Glossary of AcronymsABM Apogee Boost MotorAMSU-A Advanced Microwave Sounder Unit-AAMSU-B Advanced Microwave Sounder Unit-BAMV Atmospheric Motion Vectors (MPEF product)APT Automatic Picture TransmissionAriane The family of European satellite launch vehicles which has

been used to launch all except one MeteosatATOVS Advanced TOVS. Suite of sounding instruments including

AMSU-A, AMSU-B and HIRS/3 flown in polar orbitAVHRR Advanced Very High Resolution Radiometer for visible and

infrared imagery, flown in polar orbitbps bits per secondBRGS Back-up and Ranging Ground StationBSCC Back-up Satellite Control CentreCAL Calibration (MPEF product)CCDS Consultative Committee for Space Data SystemsCCT Computer Compatible TapeCDS Climate Data Set (MPEF product)CGMS Coordination Group for Meteorological SatellitesCLA Cloud Analysis (MPEF product)CSR Clear Sky Radiances (MPEF product)CTH Cloud Top Height (MPEF product)DADF Data Acquisition and Dissemination FacilityDarmstadt Location of EUMETSAT headquarters and Mission Control

Centre (close to Frankfurt, Germany)DCP Data Collection PlatformDCS Data Collection SystemDLT Digital Linear TapeDRS DCP Retransmission SystemECMWF European Centre for Medium-Range Weather ForecastsESA European Space AgencyEPS EUMETSAT Polar System



ERB Earth Radiation BudgetEUMETSAT The European organisation for the exploitation of

meteorological satellitesFGGE First Global GARP ExperimentFSD Foreign Satellite DataFTP File Transfer ProtocolFY-2 Feng-Yun –2 (geostationary meteorological satellite of the

People’s Republic of China)GARP Global Atmospheric Research ProgrammeGERB Geostationary Earth Radiation Budget experimentGEOSAR Geostationary Search and RescueGII Global Instability Index (MPEF product)GMS Geostationary Meteorological Satellite (operated by Japan)GOES Geostationary Operational Environmental Satellite (operated

by the USA)GOMS Geostationary Operational Meteorological Satellite (operated

by Russia)GPCP Global Precipitation Climatology ProjectGRAS Global Navigation Satellite System Receiver for Atmospheric

SoundingGTS Global Telecommunication System of the WMOHIRS High resolution InfraRed SounderhPa HectopascalHPI High Resolution Precipitation Index (MPEF product)HRI High Resolution ImageHRIT High Rate Information TransmissionHRUS High Rate User StationHRV High Resolution Visible (MSG imaging channel)HSM Hierarchical Storage ManagementIDCS International Data Collection SystemIDS ISCCP Data Set (MPEF product)IMPF Image Processing FacilityINDOEX Indian Ocean ExperimentINSAT Indian geostationary multi-function satellite



IR InfraRed (the Meteosat imaging channel operating in this partof the spectrum)

ISCCP International Satellite Cloud Climatology Projectkbps Kilobits per secondkHz KilohertzKourou Ariane launch site (in French Guiana, South America)Lannion Location of the Meteosat image relay facilities (in north-west

France)LEOP Launch and Early Orbit PhaseLRIT Low Rate Information TransmissionLRUS Low Rate User StationMAP Mesoscale Alpine ProgrammeMARF Meteorological Archive and Retrieval FacilityMbps Megabits per secondMCC Mission Control CentreMeteor Polar meteorological satellite series of RussiaMeteosat The EUMETSAT geostationary meteorological satelliteMetop Meteorological Operational polar satellite of EUMETSATMDD Meteorological Data DistributionMDD Meteorological Data Dissemination (MSG)MHz MegahertzMKU Meteosat Key UnitMOP Meteosat Operational ProgrammeMPEF Meteorological Products Extraction Facilitymrad MilliradiansMSG Meteosat Second GenerationMTP Meteosat Transition ProgrammeMTSAT Meteorological and Telecommunications SATellite (a new

geostationary satellite to be operated by Japan)MUBM Meteosat User station Baseband ModuleNMS National Meteorological ServiceNWP Numerical Weather PredictionNOAA National Oceanic and Atmospheric Administration (of the USA)PDUS Primary Data User Station



PGS Primary Ground StationSAF Satellite Application FacilitySDUS Secondary Data User StationSEVIRI Spinning Enhanced Visible and Infrared ImagerSKU Station Key UnitTD Technical DocumentationTH Tropospheric Humidity (MPEF product)TIROS Television and InfraRed Observation SatelliteTOVS TIROS Operational Vertical SounderTOZ Total Ozone (MPEF product)UG User GuideU-MARF Unified Meteorological Archive and Retrieval FacilityUsingen Location of the MSG PGS and BSCC in GermanyVIS Visible (the Meteosat imaging channel operating in this part of

the spectrum)WEFAX Weather Facsimile (the universal geostationary analogue

image dissemination service)WMO World Meteorological OrganizationWV Water Vapour (the Meteosat imaging channel operating in this

part of the spectrum)WWW World Wide Web

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