Meteosat Second Generation

System Overview

EUM TD 07

METEOSAT SECOND GENERATION MSG System Overview EUM TD 07

Issue 1.1

EUM TD 07 Issue 1.1, 25 May 2001 Meteosat Second Generation System Overview

Document Change Record

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

Page II EUM TD 07 - Issue 1.1, 25 May 2001 Meteosat Second Generation System Overview

Table of Contents

1. PREFACE 1

2. INTRODUCTION 2 2.1. Scope and Objectives 2 2.2. EUMETSAT Satellite Programmes 3 2.2.1. MSG Programme Objectives 4 2.3. Document Hierarchy 5

3. MSG OPERATIONAL SERVICES 6 3.1. Image Data Dissemination Service 7 3.2. Data Collection and Retransmission Service 8 3.3. Meteorological Data Dissemination Service 9 3.4. Meteorological Product Extraction and Distribution Service 9 3.5. Archived Data and Retrieval Service 9 3.6. Geostationary Earth Radiation Budget Service 10 3.7. User Support Service 11 3.7.1. Operational Information 11 3.7.2. User Service Helpdesk 12

4. MSG SYSTEM DESCRIPTION 13 4.1. MSG Space Segment 13 4.1.1. The MSG Satellite 13 4.1.2. The SEVIRI Radiometer 15 4.1.2.1. Scanning Concept 16 4.2. The MSG Ground Segment 18 4.2.1. The Mission Control Centre 19 4.2.1.1. The Central Facility 19 4.2.1.2. Image Processing Facility 19 4.2.1.3. Data Acquisition and Dissemination Facility 20 4.2.2. Primary Ground Station 20 4.2.3. Back-up Satellite Control Centre 22 4.2.4. Back-up and Ranging Ground Station 22 4.2.5. Foreign Satellite Data Support 22 4.2.6. Application Ground Segment 22 4.2.6.1. Meteorological Products Extraction Facility 22 4.2.6.2. Unified Meteorological Archive and Retrieval Facility 23 4.2.7. Satellite Application Facilities 23 4.2.7.1. Support of Nowcasting and Very Short Range Forecasting SAF 24 4.2.7.2. Ocean and Sea Ice SAF 24 4.2.7.3. Ozone Monitoring SAF 25 4.2.7.4. Climate Monitoring SAF 26 4.2.7.5. Numerical Weather Prediction SAF 26 4.2.7.6. Land Surface Analysis SAF 27

5. ANNEX I COMPARISON BETWEEN MTP AND MSG 29 5.1. Image Data Generation 29 5.2. Image Data Dissemination Service 31 5.3. Foreign Satellite Data Support Service 31 5.4. Meteorological Data Dissemination Service 31 5.5. Meteorological Product Extraction and Distribution Service 32 5.6. Data Collection Service 33

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5.7. Archived Data and Retrieval Service 33 5.8. 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 and photographs for this document but for which a specific acknowledgement has not been possible.

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1. Preface

This document presents a general introduction to the products, services and facilities provided by EUMETSAT through the Meteosat Second Generation (MSG) System. It provides an overview of the complete system, focusing on EUMETSAT services and including descriptions of the MSG space and ground segments.

Like the first series of satellites, the primary service of Meteosat Second Generation 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 of Africa, most of the North and South Atlantic oceans and some portions of South America (as illustrated in Figure 1.1). However, the Meteosat Second Generation system has many improvements over its predecessors and new features, which this document introduces.

This document is complementary to a previous publication, EUM TD 05, that describes the Meteosat system for the Meteosat Transition Programme (MTP). It includes a comparison between the services offered by the MTP and the MSG systems. The transfer phase between the two programmes is also mentioned, albeit briefly, since EUMETSAT Newsletters and information on the EUMETSAT Web 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.

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2. Introduction

This chapter recalls the reasons why meteorology and climatology are so important to the global economy and the contribution of meteorological satellites to those disciplines. The EUMETSAT satellite programmes and the specific MSG objectives are described briefly. The document tree for user information is also included.

2.1. Scope and Objectives

Meteorological satellites have become essential tools for both meteorology and climatology; they provide vital data for these disciplines at frequent intervals and over wide areas. They continue the two fundamental concepts of data exchange and international co-operation that have been traditional in these fields for more than 150 years. International co-operation exists at two levels: First at the European level through those countries which have come together to establish EUMETSAT. The continuity of the Meteosat system enabled through the Second Generation 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 the availability of satellite data over the entire Earth.

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

The data and services are mainly focused on the requirements of operational meteorology, 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 and the monitoring of planet Earth.

Precise and accurate weather forecasts are of much greater importance than their 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 and reliable operations, for the construction and agricultural industries to schedule activities that may be affected by weather, and by the retail industry to plan stocks of food and clothing for which the demand varies according to the weather. The energy industries also vary the available capacity of their plants according to weather-dependent predictions of demands. Accurate weather forecasts are therefore a strong contributor to the efficiency of the way in which many industries work and therefore a strong contributor to national economies.

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

The variations in weather and climate have enormous economic consequences which are increasing as the world population grows and becomes more industrialised. The need to understand, monitor and predict the weather and the changing climate is becoming increasingly important.

2.2. EUMETSAT Satellite Programmes

The initial development and early operation of Meteosat was covered by a series of ESA programmes. After EUMETSAT was defined in 1983, ESA initiated the Meteosat Operational Programme (MOP), and from 1987 this was conducted as a joint programme, under the overall authority of EUMETSAT. This programme provided 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 1983 until the end of November 1995.

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

Meteosat Second Generation is a significantly enhanced follow-on system to that operated under the MTP. It has been designed in response to user requirements and will serve the needs of nowcasting applications and short range weather forecasting as well as providing important data for climate monitoring and research. The development of Meteosat Second Generation continues the successful co-operation between EUMETSAT and ESA, with two thirds of the cost of the development of the first satellite being funded by ESA. The financial envelope already approved by the EUMETSAT Council covers the operation of three MSG satellites from the year 2002 for more than a decade. Consideration is being given to the manufacture of a fourth satellite in this series.

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

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EUMETSAT Polar System (EPS), now in preparation, is the European component 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 series will 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 radiance emitted by the atmosphere, with improved radiometric, spectral, spatial and temporal 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 very short range forecasting; 4) extraction of meteorological and geophysical fields from the satellite image data in support of general meteorological, climatological and environmental activities; 5) user support including the provision of user documents and information, the provision of a user helpdesk facility and of a service to enable access to archived MSG image data and products; 6) support to secondary payloads of scientific or pre-operational nature (GERB and Search & Rescue (GEOSAR)) which are not directly relevant to the MSG Programme. These payloads do not drive the system nor do they interfere with 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 to learn more about the Meteosat Second Generation System and the services that EUMETSAT will operate to accomplish the mission objectives. Please see the following section for a document hierarchy.

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2.3. Document Hierarchy

Figure 2.1 below shows the EUMETSAT technical document set. Documents EUM TD 01 - 06 describe the services of the current Meteosat Transition Programme (MTP). The series will be extended to cover the entire range of services operating under Meteosat Second Generation (MSG). Whilst EUM TD 07 “Meteosat Second Generation System Overview” will provide an overview for all products and services available via the MSG system users are encouraged to refer to the documents EUM TD 08 –12 for a more detailed description of the services and how to access them.

MTP EUM TD 05 The Meteosat System

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

MSG EUM TD 07 Meteosat Second Generation System Overview

EUM TD 08 Image Data Dissemination Service

EUM TD 09 Data Collection and Retransmission Service

EUM TD 10 Meteorological Data Dissemination Service

EUM TD 11 Meteorological Product Extraction and Distribution Service

EUM TD 12 Archived Data Retrieval Service

Figure 2.1 User Document Hierarchy

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3. MSG Operational Services

The primary service provided by the Meteosat Second Generation system is the generation of multi-spectral images of the Earth and the transmission of these image data to users in the shortest practical time.

In addition there are several other important services as follows:

Ø The Data Collection & Retransmission Service;

Ø The Meteorological Data Dissemination Service;

Ø The Meteorological Product Extraction and Distribution Service;

Ø The Archive Data and Retrieval Service;

Ø The GERB Service;

Ø The User Support Service.

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

The operational Meteosat satellites are positioned in geostationary orbit, above the equator, normally at 0° longitude, i.e. the Greenwich Meridian. From this position the satellite is capable of providing images of all of Europe, the Middle East, the entire continent of Africa, most of the North and South Atlantic oceans and some portions of South America. Similarly the satellite is able to disseminate these data to users in an extensive area of the globe. The telecommunications coverage area for data dissemination and unrestricted access to the services operated by EUMETSAT is illustrated in Figure 3.1. Note that the 'nominal coverage area' shown includes all the EUMETSAT Member States, all of Africa and locations at which the elevation to the satellite is greater than or equal to 10°.

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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 the Spinning Enhanced Visible and IR Imager (SEVIRI). The SEVIRI takes basic multi-spectral imagery with better spectral, spatial and temporal resolution than the previous Meteosat satellites. The SEVIRI takes images of the earth, measuring the radiance at 12 different wavebands of the electromagnetic spectrum. The various channels provide measurements of different physical characteristics of the atmosphere and the earth at a resolution of 3 km at the sub-satellite point. High resolution imagery is acquired by observing the Earth in the visible band and sampling at 1 km resolution.

During normal operations the radiometers capture new images of the earth every 15 minutes. The earth images and other meteorological data are disseminated via the satellite so that information regarding the current meteorological conditions may be received by users in as short a time as practical. The MSG satellites are equipped with transponders to transmit information to user stations located anywhere within the field of view of Meteosat. MSG supports two channels of dissemination via the satellite, the Low Rate Information Transmission (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 include image data from other geostationary satellites including the US satellites, GOES- E and GOES-W over the western Atlantic and eastern Pacific, Japan’s GMS satellite over the western Pacific and the Russian GOMS satellite over the Indian Ocean. The LRIT transmission also delivers Meteorological Products from

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

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

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

In addition to the direct dissemination via satellite an MSG Internet image dissemination Service is planned which will provide some of the services formerly available to users from the WEFAX broadcast in MTP operations. Further information about the content of this service and conditions of access may be obtained from the EUMETSAT Web site.

3.2. Data Collection and Retransmission Service

Data Collection Platforms (DCP) are automatic or semi-automatic environmental observing systems. Typical examples are automatic weather stations located at remote 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 the collection and relay of Data Collection Platform Messages established with the first generation of Meteosat satellites. As a baseline, all basic operating characteristics will generally remain unchanged, however, there is a significant increase in the capacity of the MSG Data Collection System.

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

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

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3.3. Meteorological Data Dissemination Service

The MDD Service operating under the MTP will have a similar equivalent in MSG Operations. The MDD data will be included in the LRIT data stream, thus ending the requirement for a separate user station for the reception of MDD data. The alphanumeric MDD messages are mainly meteorological reports in conventional numeric codes that are suitable for human interpretation but can also be used within computer systems. The binary MDD data are bit-level transmissions for use within user computer systems to generate charts; the pictorial MDD products are mainly charts for direct human interpretation. The MDD data relay is considered as a space-based extension of the Global Telecommunication System (GTS) of the WMO. Therefore access to these data follows the same conditions as for the conventional GTS systems, namely access rights are usually only granted to National Meteorological Services. This control is achieved through the means of encryption.

Access to the MDD Service is controlled by the EUMETSAT User Support Service. Further detailed information about the service may be found in the publication 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 and climatological products and their subsequent dissemination to users. This is accomplished within the Meteorological Products Extraction Facility (MPEF), located within the Mission Control Centre (MCC) in the EUMETSAT headquarters. The MPEF has been designed to allow new products to be added when user requirements have been determined and algorithm development is completed. 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 section 3.1). In addition all products are archived and may be requested by users of the Archived Data Retrieval Service (see section 3.5).

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

3.5. Archived Data and Retrieval Service

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

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Retrieval Facility (U-MARF). Its objective is to maintain a permanent archive containing all the imagery from the first and second generation Meteosat satellites as well as from the future EUMETSAT Polar System (EPS). In addition to the imagery, the archive stores all supporting information and centrally produced meteorological and climatological products, as well as the SAF product catalogue.

The U-MARF has been designed to supersede the MARF, which was established to 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 in 2002. The U-MARF uses new technology to manage the increase in data volume from the MSG satellites and significantly enhances the services for data access available to users.

A detailed description of the U-MARF and its products and services may be found in the publication EUM TD 12 Archived Data Retrieval Service. In addition, the following dedicated User Support Service Helpdesk point-of-contact exists for all 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 the Geostationary Earth Radiation Budget (GERB) instrument for flight on the MSG-1 satellite.

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

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

The GERB system comprises the GERB instrument and a de-centralised GERB ground segment. The GERB instrument is a scanning radiometer with two broadband channels, one covering the solar spectrum, the other covering the entire electromagnetic spectrum. Data will be calibrated on board in order to support the retrieval of radiative fluxes of reflected solar radiation and emitted thermal radiation at the top of the atmosphere with an accuracy of 1%.

The GERB data are received at the EUMETSAT ground segment and passed on to the GERB ground segment for data processing. The data and products are then distributed by RAL.

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

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

3.7. User Support Service

The EUMETSAT User Support Service has been established to meet the growing demand for information from the users of EUMETSAT satellite data. This Service has key roles providing an effective interface to the services and a helpdesk facility for the user community, exchanging information with other satellite operators and providing key contact information for the various satellite services (e.g. image dissemination, DCP and MPEF products). In addition the User Support Service is providing the resources and information necessary to help the transition of many thousands of users of data from the Meteosat Transition 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 of the Meteosat Programme a considerable number and a wide variety of users’ needs have to be fulfilled. This requires a mechanism for effectively gathering and channelling requests of great variety from the user community as a whole and to satisfactorily respond to such requests within an acceptable time frame. The user community is, in fact, composed of many different user groups with differing needs (e.g. meteorologists, researchers, environmental services, educational establishments, press, media and many others). User enquiries might 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 user documentation.

3.7.1. Operational Information

Operational information is distributed to users in a variety of ways. The primary source of information is via the EUMETSAT web site. Administrative messages are also transmitted within the MSG LRIT and HRIT services to inform users about special operations or possible breaks in service, giving as much notice as possible. In addition, users will, from time to time, receive newsletters that give up-to-date information about the system and include the latest dissemination baseline.

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3.7.2. User Service Helpdesk

The Helpdesk facility is open to all users to submit their enquiries concerning any EUMETSAT product or service. The Helpdesk staff is committed to responding to user enquiries within 3 working days wherever possible and, when internal investigations are involved, to fully respond within a maximum of 15 working days (with an interim response supplied within 3 working days). Alternative points of contact are provided (see below) for enquiries related to the Archived Data Retrieval Service. The accumulation of the many and varied user enquiries processed over several years of operations has resulted in the establishment of Frequently Asked Questions (FAQs) and a comprehensive list of these will be maintained on the EUMETSAT Web site.

The points of contact for the Helpdesk are:

Mail: EUMETSAT User Service Am Kavalleriesand 31 D - 64295 Darmstadt Germany

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

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4. MSG System Description

Figure 4.1 Illustration of the MSG System

The Meteosat Second Generation System provides a comprehensive set of products and services involving the dissemination of information via the satellite and by other means. The MSG system consists of a space segment and a ground segment. It is designed to provide products and services over a lifetime of 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 nominal location at 0º degrees longitude over the equator, and foresees a stand-by satellite that would be used in case of emergencies or during major configuration changes.

4.1. MSG Space Segment

4.1.1. The MSG Satellite

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

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

The Meteosat Second Generation Satellite is shown in an exploded view in Figure 4.3. The satellite is basically cylindrical with an overall size of 3.7 m in diameter and 2.4 m in height. The MSG spacecraft is composed of three main sections. The top section contains the mission communications payload including the antennas and transponders required for satellite monitoring and control, down-linking the raw data from the SEVIRI radiometer and GERB instrument, relay of DCP data, dissemination of LRIT and HRIT information, as well as the relay of distress signals. The middle section contains the SEVIRI instrument and it’s associated electronics. The bottom section contains the satellite propulsion systems and components for the orbit and attitude control.

Figure 4.2 Exploded view of the MSG Satellite

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The surface of the satellite is covered with solar cells that provide the electrical power for operating the satellite, although two rechargeable batteries are also available 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-clockwise direction around its main axis, which is aligned nearly parallel to the Earth's north-south axis. The spin is required to both stabilise the satellite and to assist in 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 the basic data of the Meteosat Second Generation system, namely 12 channels spanning the visible and infrared parts of the electromagnetic spectrum somewhat similar to those of the AVHRR instrument flown on the US NOAA satellites in polar orbits. There is one high resolution channel, imaging in the visible region of the spectrum, which can be used to support nowcasting and very short-range forecasting applications. There are also seven ‘multi-spectral’ imaging channels providing, amongst other information, data about the temperatures of clouds, land and sea surfaces.

Figure 4.3 Illustration of the SEVIRI instrument

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4.1.2.1. Scanning Concept

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

One complete revolution of the satellite lasts 0.6 seconds, of which only about 30 milliseconds are available over the Earth disk to acquire one scan. For each scan step several image lines are acquired (3 lines for nominal channels and 9 lines 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, data transmission and measurements directed at deep space, used for removal of noise 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 mirror retrace. The satellite can obtain shorter repeat cycles if a reduced area of the Earth is imaged.

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

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Figure 4.5 HRV Detectors / IR & VNIR Detectors Pixel Acquisition

The scans of data are taken at constant angular steps, and this together with the natural curvature of the earth means that as the satellite scans away from the sub-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 4.6 where the respective sizes of pixels are illustrated as a function of their position on 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)

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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 MSG Ground 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, hosting also the Back-up Satellite Control Centre (BSCC) and providing the primary interface between the satellite and the MCC, including all ranging functions 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 CMC Lannion. • an Application Ground Segment, which extracts meteorological and geophysical products from the calibrated and geolocated image data generated by the MCC. The Applications Ground Segment is composed of the Meteorological Product Extraction Facility (MPEF) and the Unified Meteorological Archive and Retrieval Facility (U-MARF), both located at EUMETSAT Headquarters, as well as a distributed network of Satellite Application Facilities (SAF).

EUMETSAT Overall Ground Infrastructure EUMETSAT HQ Central Facilities

Acquisition and Control Station

Back-up or Support Station

Satellite Application Facility host site

Madrid (E): Suppport toNowcasting and very Helsinki Short Term Forecasting Lannion (F): Ocean and Sea Ice Helsinki (FIN): Ozone Monitoring Offenbach (D): Climate Monitoring Copenhagen Bracknell (UK): Numerical Weather Prediction Bracknell Offenbach Copenhagen (DK): GRAS Meteorology MDD-FDRS Lisboa (P): Land Surface Analysis EUMETSAT HQ Darmstadt FSDS MCC + MPEF PGS Primary Ground Station Weilheim Usingen MDD Meteorlogical Data Distribution Meteosat BGS BRGS Back-up and Ranging Station Lannion MSG PGS FSDS Foreign Satellite Data Support Toulouse CDA Command and Data Acquisition MDD MCC Mission Control Centre Fucino MPEF Met. Product Extraction Facility Meteosat PGS Lisboa Roma Madrid MDD

Canary Island MSG BRGS

Figure 4.7 EUMETSAT Overall Ground Infrastructure

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4.2.1. The Mission Control Centre

The Mission Control Centre (MCC) is the prime operations centre and is responsible for the monitoring and control of the main components of the MSG system, including the spacecraft, the telecommunication elements and most of the ground segment. It is located in the Operations wing of the EUMETSAT headquarters building in Darmstadt, Germany. The MCC is thus the core of the Meteosat ground segment. Dedicated communications links connect it to the Primary 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 control infrastructure for the satellite and the ground segment. This includes the planning, scheduling and execution of activities and the centralised monitoring and control of all components. The facility is highly automated in several areas to ease daily operations. The facility is responsible for the central configuration and control of software and databases that operate in the MCC. It is also responsible for local archiving and providing the means for the analysis of operational data (e.g. monitoring or housekeeping data from the ground segment and the satellite).

The basis for all activity within the system is the operations plan. This governs the routine cycle of operations and is monitored using Central Facility consoles. Routine spacecraft commands are stored in the computer system and transmitted 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 the spacecraft are all displayed on the consoles. Many hundreds of parameters are monitored for each spacecraft.

The configuration of the spacecraft and the ground segment can also be shown on the consoles, with displays showing which of the redundant components are in active use and which are available in stand-by mode. The system permits reconfiguration of both the spacecraft and the ground station under software control from the consoles. This includes the facility for remote operation and control 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 the image from each set of detectors coincides with the other images. At the same

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time, the sampling removes any slight perturbations caused by the movement of the spacecraft, thereby rectifying the image so that it appears to come from the nominal location of the spacecraft. The data are then adjusted according to certain calibration information. The IMPF is also responsible for the automatic radiometric and geometric quality assessment of the data. The image is passed in segments from the IMPF to the dissemination facility for immediate relay to users, to the Meteorological Product Extraction Facility (MPEF) for further processing 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 the various types of data required for dissemination through the satellite via the Low Rate 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 data from the Support Ground Segment. The data are formatted and prioritised for transmission. Depending on the type of data the formatting may include compression and encryption.

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

The Data Collection messages are also monitored within the DADF. Messages from DCPs are received in the Primary Ground Station from the Meteosat Second Generation satellite and transmitted immediately to the MCC in Darmstadt. There they are compared with the master list of expected DCP reports and processed and distributed as appropriate. This operation is performed entirely automatically.

4.2.2. Primary Ground Station

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

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

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To reliably accomplish these vital tasks a considerable amount of redundancy is incorporated in the station design which, to a great extent, can function completely automatically.

Two fully steerable 13-metre diameter parabolic antennas are located at the PGS and used exclusively to support all communications with MSG. Each antenna is capable of supporting all the transmissions and data reception required for one spacecraft 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 control system located in Usingen and interacting with the MCC in Darmstadt. The PGS can operate in two different modes: remotely, under the control of the MCC, or through the use of the local system consoles. This flexibility ensures maximum reliability in case of problems.

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4.2.3. Back-up Satellite Control Centre

Also located at the PGS is a Back-up Satellite Control Centre (BSCC). This is established as a functional extension of the MCC in Darmstadt so that in an extreme emergency it could be used in a stand-alone mode to monitor and control the spacecraft and the PGS, as well as to perform all essential flight activities. It is not designed to support the user services but does ensure the safety 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 to allow accurate ranging measurements to be made to determine the precise location and orbit of the MSG satellites.

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

4.2.5. Foreign Satellite Data Support

The satellite ground station facilities owned and operated by the French meteorological service in Lannion have been associated with the Meteosat system since the start of operations in 1977. EUMETSAT provides and maintains facilities at Lannion for the relay of image data from additional satellites, to complement the Meteosat images transmitted from the PGS. The primary requirement is to relay images covering the western part of the Atlantic and the Americas. These images are obtained from GOES-E, GOES-W, GOMS and GMS. MSG will continue to carry that mission through its data dissemination and aims at an expansion of the current service to meet the requirement of the Global Observing System (GOS) to provide a near global data coverage several times 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 the Mission Control Centre and comprises another network of dedicated workstations, which receive pre-processed images from the IMPF and process

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them, together with ancillary data, to extract quantitative meteorological and climatological products. The MPEF also is responsible for monitoring the quality of the products (by comparison with independent observations) and of image data calibration. Image display and analysis tools allow the operators to monitor the 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 time retrieval capability for all of the imagery and meteorological products owned by EUMETSAT. This includes the data from the Meteosat Operation Programme, Meteosat Transition Programme, Meteosat Second Generation and the future EUMETSAT Polar System. The U-MARF uses modern tape recording technology to store the data in a robotic archive system. The retrieval will be possible either via a Web-based on-line interface to the system or off-line via the Helpdesk 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 MSG Ground Segment. These SAFs are under the overall co-ordination of EUMETSAT and have the remit to develop and deliver products (or software to derive products), extracting geophysical parameters primarily from MSG and EPS satellite data. The SAFs are generally located in National Meteorological Services or other approved institutes of a EUMETSAT Member State. By utilising the specialised expertise of the Member States the SAFs complement the production of standard meteorological products derived from satellite data at EUMETSAT’s MCC. This will promote and ensure the optimum use of data from the MSG and EPS systems in their application domain.

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

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

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4.2.7.1. Support of Nowcasting and Very Short Range Forecasting SAF

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

Under the leadership of the Spanish Meteorological Institute (INM), the NWC SAF is developed by a project team involving Météo-France and the Swedish and 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 of products 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 those in numerical weather prediction, climate monitoring, transport, the fishing industry, ecology, pollution monitoring, coastal engineering and the offshore oil and gas industry.

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The SAF is developed by a consortium, led by Météo-France, and involving the Meteorological 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 a coherent set of information characterising the ocean surface and energy fluxes through 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 on ozone distribution, other trace gases, aerosols and ultraviolet data. The severe loss of stratospheric ozone in the high latitudes of the Northern Hemisphere and over the Antarctic and the subsequent increase of harmful ultraviolet radiation has been well established in various measurements. Ozone data are also important 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 by the Finnish Meteorological Institute (FMI).

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

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satellite data. Data from the EPS mission (GOME-2 instrument) will be the main input data for this SAF. The SAF will provide data for ultraviolet fields under real atmospheric conditions, total ozone, ozone profiles, aerosols and total amounts of 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 and archive high quality data sets from satellite observations, essential for the monitoring of the global climate. These data sets will assist in the analysis and diagnosis of climate parameters to identify and understand changes in the climate system.

The CLM SAF involves ten institutes from five countries: Belgium, Finland, The Netherlands, 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 top temperatures and height, cloud phase, optical thickness and cloud water path • Components of the surface radiation budget: solar surface irradiance and albedo 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 to model the atmosphere and compute forecasts extending from a few hours up to ten days. NWP is a central facility of the National Meteorological Services, crucial to the quality of their forecasting services. Observational data are the basis of NWP, and satellite information is an important element.

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

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

Concerning data from MSG, the SAF will work on improved observation operators for satellite winds, including radiative transfer models required for direct 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 the Portuguese Meteorological Institute (IM).

The LSA SAF will concentrate on developing techniques for deriving land surface parameters and radiation surface fluxes over the continents from the data provided by EUMETSAT’s satellites. The land surface data will benefit other SAFs in addition to National Meteorological Services, and government and international 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

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• 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

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5. Annex I Comparison between MTP and MSG

The Meteosat Second Generation system will continue to provide the operational services required by National Meteorological Services and other users that were established with the so-called MOP and MTP satellite series. However, due to more demanding user requirements and improvements in technology there have been changes in the implementation of these services. It is important for existing users of the MTP system to understand the differences.

5.1. Image Data Generation

The image rectification and dissemination service of the Meteosat Second Generation satellite significantly improves on the capabilities of the MTP. The radiometer on-board the MSG satellite has a total of 12 imaging channels instead of the three on the original Meteosat satellites. Images are generated every 15 minutes instead of every 30 minutes. The sampling distance of the infrared channels (at the sub-satellite point) is improved to 3km compared with 4.5km, while the new High Resolution Visible channel provides 1km instead of the previous 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 to the 720kg of the previous Meteosat satellites. The MSG satellite has a power demand three times that of the previous Meteosat satellites, 600Watts compared to 200Watts. In spite of this, the MSG satellite has been designed with a station-

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

MOP / MSG PERFORMANCE EVOLUTION 1st Generation 2nd Generation

Imaging Format

Imaging Cycle 30 min 15 min Wavelength HRV VIS 0.6 Visible 0.5-0.9 VIS 0.8 IR 1.6 Water Vapour WV 6.2 WV 6.4 WV 7.3

Channels IR Window IR 3.9 IR 8.7 IR 11.5 IR 10.8 IR 12.0 Air mass IR 9.7 + WV Analysis IR 13.4 Sampling Distance 2.25 km (visible) 1 km (HRV) 4.5 km (IR + WV) 3 km (others)

Pixel Size 2.25 km (visible)

(MTP Square-shaped compared to MSG diamond-shaped)

5 km (IR + WV)

Number of 4 42 Detectors Telescope 400 mm 500 mm Diameter Scan Principle Scanning telescope Scan mirror

Table 5.1 MOP to MSG Performance Evolution

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5.2. Image Data Dissemination Service

DATA TRANSMISSION RATES MOP MSG

Transmission raw 0.333 Mbs 3.2 Mbs data rate Disseminated 0.166 Mbs 1 Mbs (HRIT) and image 128 Kbs (LRIT)

Table 5.2 MOP to MSG Performance Evolution

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

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

5.3. Foreign Satellite Data Support Service

The global observing system of meteorological satellites, with nominal locations agreed between the satellite operators and WMO within the Co-ordination Group of 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 the meteorological community in the future.

The facilities of CMS, Lannion (France) are used for gathering the foreign satellite data rebroadcast via the Meteosat satellites. The Meteosat system provides a relay of data from GOES-E, GOES-W, GOMS and GMS data in the WEFAX and HRI broadcasts. MSG will continue this service and foreign satellite data 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 continued with MSG with MDD data being included in the LRIT data stream, thus ending

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

The Meteorological Data Distribution (MDD) service is a service providing meteorological data to areas of the world, within the view of the Meteosat satellite, which are without reliable conventional communications. In particular, it allows countries in Africa to receive observations, analyses and forecasts from major meteorological centres that would otherwise be nearly impossible to receive.

The first generation Meteosat MDD system used dedicated transmission channels to transmit data from three data up-link sites located at meteorological centres 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 satellite telecommunications field of view. The actual terminal is quite simple and consists mainly of a small parabolic antenna, a receiver, a personal computer (or workstation) and a printer. The computer can be used to display alphanumeric messages or convert these data into graphical displays. It can also be used to process and display the binary data and display the pictorial information. Since all MDD transmissions are encrypted, a Meteosat Key Unit (MKU) is also a vital part of the MDD terminal and is used to decrypt the data. Since only National Meteorological Services are allowed access to MDD data, they have to obtain the MKU directly from EUMETSAT.

5.5. Meteorological Product Extraction and Distribution Service

During MTP operations a number of products (e.g. Cloud Motion Winds) have been produced in a routine fashion. In the Meteosat Second Generation system also a variety of products is produced to ensure the continuity of the space-based observations in an enhanced manner (see chapter 3.4). These products will be complemented by products derived at the Satellite Application Facilities (SAF) which are centres of excellence located in a National Meteorological Service or other approved institutes of EUMETSAT Member States. These centres are generally dedicated to the study of different thematic areas associated with meteorology and climatology.

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

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5.6. Data Collection Service

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

These changes may require some DCP operators to alter the transmitting frequency of their DCP. There may also be a need to re-certify certain designs of DCP before they can be allowed to operate with MSG. For information regarding the certification of new and existing Data Collection Platforms into the MSG system refer to TD09 “Data Collection and Retransmission (DCS) Service”. Furthermore, considering that Meteosat-7 will be located close to 10ºW during the period of parallel MTP/MSG operations, the area of reception coverage will not be as it is from zero degrees longitude. EUMETSAT is working closely with the 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 DCP messages.

5.7. Archived Data and Retrieval Service

The U-MARF, will provide a permanent store for all images and meteorological data at EUMETSAT. The previously named archive facility, MARF, housing the MOP and MTP data, will be incorporated with data from MSG and the EUMETSAT Polar System (EPS) in a standard format. The U-MARF also includes 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 being the 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 has agreed to continue the MTP services until at least the end of 2003. Meteosat-7 will be moved to a new orbital position close to 10ºW in order to prevent any interference with the MSG service. Therefore, users who wish to continue using the MTP dissemination services will need to re-point their user-station antennas in order to continue reception.

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

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

Mapping of Services from MTP to MSG Service MTP MSG Image Data Dissemination HRI / WEFAX LRIT / HRIT Service Internet Internet Meteorological Data Dedicated transmission LRIT Dissemination Service channels to transmit data from 3 up-link sites Meteorological Product GTS LRIT Extraction and Distribution Distributed via WEFAX (one GTS Service product only) Data Collection and DRS (Channel A1 1691 MHz) LRIT Retransmission Service GTS GTS Internet Internet Foreign Satellite Data Support HRI / WEFAX LRIT Service Internet Internet Archived Data and Retrieval MARF U-MARF Service GERB Service Not available To be announced GEOSAR Not available Relay distress signals of 406MHz beacons User Support Service EUMETSAT EUMETSAT Internet Internet

Table 5.3 Mapping of Services from MTP to MSG

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6. Annex II EUMETSAT Data Policy

The products and services from Meteosat and other EUMETSAT meteorological satellites are made available to a wide user community. Access and use are subject to terms and conditions set by the EUMETSAT Council.

The Council has decided that some products are available on a free and unrestricted basis as "essential" data in the sense of Resolution 40 (Cg-XII) of the World Meteorological Organization (WMO). For products that do not fall in this category measures exist to control user access. For those disseminated via the LRIT and HRIT service the transmissions are encrypted and a special device called a Station Key Unit (SKU) for MSG and EPS data, (MKU) for MTP data, is required to decode the broadcasts. Some services are granted subject to the conclusion 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 all products and services for their Official Duty Use free of charge; 2. In the EUMETSAT Member States and Co-operating states, the NMSs act as EUMETSAT's agents for the purpose of granting access to real-time data. In case of commercial use, equal conditions apply to NMSs and non- governmental organisations; 3. Outside the EUMETSAT Member States and when dealing with international organisations, EUMETSAT is the direct licensing authority for products and services. Both within and outside Member States EUMETSAT is responsible for 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 are available 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 those listed above is subject to certain terms and conditions, possibly including the payment of fees.

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

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

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7. List of Figures

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...... 1 Figure 2.1 User Document Hierarchy...... 5 Figure 4.1 Illustration of the MSG System...... 13 Figure 4.2 Exploded view of the MSG Satellite...... 14 Figure 4.3 Illustration of the SEVIRI instrument ...... 15 Figure 4.4 Image acquisition by the SEVIRI radiometer ...... 16 Figure 4.5 HRV Detectors / IR & VNIR Detectors Pixel Acquisition ...... 17 Figure 4.6 SEVIRI multi-spectral image ground resolution (equivalent surface)...... 17 Figure 4.7 EUMETSAT Overall Ground Infrastructure...... 18 Figure 4.8 A MSG 13 metre antenna at the PGS at Usingen, Germany.... 21 Figure 5.1 A side-by-side comparison of the Meteosat First and Second Generation satellites ...... 29

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8. List of Tables

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

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9. Glossary of Terms

Advanced Very Cross-track multi-spectral scanner on a NOAA polar-orbiting satellite that High acquires five spectral bands of data (0.55 to 12.50 µm) with a ground Resolution resolution cell of 1.1km by 1.1km. Radiometer (AVHRR) 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 an exponent of the base 2. Blackbody An ideal substance that absorbs all the radiant energy incident on it and emits radiant energy at the maximum possible rate per unit area at each wavelength for any given temperature. No actual substance is a true blackbody, although some substances, such as lampblack, approach its properties. 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 electromagnetic radiation into a recorded signal. Digital number Value assigned to a pixel in a digital image. (DN) Electro- Energy propagated in the form of an advancing interaction between electric magnetic and magnetic fields. All electromagnetic radiation moves at the speed of radiation light. Electro- Continuing sequence of electromagnetic energy arranged according to magnetic wavelength or frequency. spectrum Emission Process by which a body radiates electromagnetic energy. Kinetic temperature and emissivity determine emission. Frequency Number of wave oscillations per unit time or the number of wavelengths that pass a point per unit time. Geometric Image-processing procedure that corrects spatial distortions in an image. correction Geostationary Refers to satellites travelling at the angular velocity at which the earth rotates; 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 wavelengths from 0.7µm to 1mm. Multi-spectral Scanner system that simultaneously acquires images of the same scene at scanner different wavelengths. Nadir Point on the ground directly in line with the satellite and the centre of the earth.

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Noise Random or repetitive events that obscure or interfere with the desired information. Orbit Path of a satellite around a body such as the earth, under the influence of gravity. Picture element In a digitised image, the area on the ground represented by each digital number. Commonly contracted to pixel. Radiant flux Rate of flow of electromagnetic radiation measured in watts per square centimetre. 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 specific wavelength interval. Resolution Ability to separate closely spaced objects on an image. Resolution is commonly expressed as the most closely spaced line-pairs per unit distance 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 scanning system. Scanner An imaging system in which the field of view of one or more detectors is swept across the terrain. Sensor Device that receives electromagnetic radiation and converts it into a signal that 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 reception of a pre-determined signal. Visible Energy at wavelengths from 0.4 to 0.7µm that is detectable by the human radiation eye. Wavelength (λ) Distance between successive wave crests or other equivalent points in a harmonic wave.

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10. Glossary of Acronyms

ABM Apogee Boost Motor AMSU-A Advanced Microwave Sounder Unit-A AMSU-B Advanced Microwave Sounder Unit-B AMV Atmospheric Motion Vectors (MPEF product) APT Automatic Picture Transmission Ariane The family of European satellite launch vehicles which has been used to launch all except one Meteosat ATOVS Advanced TOVS. Suite of sounding instruments including AMSU-A, AMSU-B and HIRS/3 flown in polar orbit AVHRR Advanced Very High Resolution Radiometer for visible and infrared imagery, flown in polar orbit bps bits per second BRGS Back-up and Ranging Ground Station BSCC Back-up Satellite Control Centre CAL Calibration (MPEF product) CCDS Consultative Committee for Space Data Systems CCT Computer Compatible Tape CDS Climate Data Set (MPEF product) CGMS Coordination Group for Meteorological Satellites CLA Cloud Analysis (MPEF product) CSR Clear Sky Radiances (MPEF product) CTH Cloud Top Height (MPEF product) DADF Data Acquisition and Dissemination Facility Darmstadt Location of EUMETSAT headquarters and Mission Control Centre (close to Frankfurt, Germany) DCP Data Collection Platform DCS Data Collection System DLT Digital Linear Tape DRS DCP Retransmission System ECMWF European Centre for Medium-Range Weather Forecasts ESA European Space Agency EPS EUMETSAT Polar System

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ERB Earth Radiation Budget EUMETSAT The European organisation for the exploitation of meteorological satellites FGGE First Global GARP Experiment FSD Foreign Satellite Data FTP File Transfer Protocol FY-2 Feng-Yun –2 (geostationary meteorological satellite of the People’s Republic of China) GARP Global Atmospheric Research Programme GERB Geostationary Earth Radiation Budget experiment GEOSAR Geostationary Search and Rescue GII 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 Project GRAS Global Navigation Satellite System Receiver for Atmospheric Sounding GTS Global Telecommunication System of the WMO HIRS High resolution InfraRed Sounder hPa Hectopascal HPI High Resolution Precipitation Index (MPEF product) HRI High Resolution Image HRIT High Rate Information Transmission HRUS High Rate User Station HRV High Resolution Visible (MSG imaging channel) HSM Hierarchical Storage Management IDCS International Data Collection System IDS ISCCP Data Set (MPEF product) IMPF Image Processing Facility INDOEX Indian Ocean Experiment INSAT Indian geostationary multi-function satellite

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IR InfraRed (the Meteosat imaging channel operating in this part of the spectrum) ISCCP International Satellite Cloud Climatology Project kbps Kilobits per second kHz Kilohertz Kourou 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 Phase LRIT Low Rate Information Transmission LRUS Low Rate User Station MAP Mesoscale Alpine Programme MARF Meteorological Archive and Retrieval Facility Mbps Megabits per second MCC Mission Control Centre Meteor Polar meteorological satellite series of Russia Meteosat The EUMETSAT geostationary meteorological satellite Metop Meteorological Operational polar satellite of EUMETSAT MDD Meteorological Data Distribution MDD Meteorological Data Dissemination (MSG) MHz Megahertz MKU Meteosat Key Unit MOP Meteosat Operational Programme MPEF Meteorological Products Extraction Facility mrad Milliradians MSG Meteosat Second Generation MTP Meteosat Transition Programme MTSAT Meteorological and Telecommunications SATellite (a new geostationary satellite to be operated by Japan) MUBM Meteosat User station Baseband Module NMS National Meteorological Service NWP Numerical Weather Prediction NOAA National Oceanic and Atmospheric Administration (of the USA) PDUS Primary Data User Station

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PGS Primary Ground Station SAF Satellite Application Facility SDUS Secondary Data User Station SEVIRI Spinning Enhanced Visible and Infrared Imager SKU Station Key Unit TD Technical Documentation TH Tropospheric Humidity (MPEF product) TIROS Television and InfraRed Observation Satellite TOVS TIROS Operational Vertical Sounder TOZ Total Ozone (MPEF product) UG User Guide U-MARF Unified Meteorological Archive and Retrieval Facility Usingen Location of the MSG PGS and BSCC in Germany VIS 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 Organization WV Water Vapour (the Meteosat imaging channel operating in this part of the spectrum) WWW World Wide Web

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