The GMES-Sentinels Flight Operations Segment

The Global Monitoring for Environment and Security (GMES) programme main objective is to support Europe’s goals regarding sustainable development and global governance of the environment by providing timely and quality data, information, services and knowledge. To achieve this objective, the GMES programme features a Space Segment component comprising five Sentinels mission families. Scheduled for launch in 2012 and 2013, Sentinels 1, 2 and 3 represent the first step in the deployment of the GMES Space Segment. They are regarded as operational missions and as such require a high degree of reliability and availability also at the level of the ground segment while minimising the operational effort associated to the routine mission phase. This paper will describe the Operational Concept applied across the 3 missions highlighting the innovative aspects, in particular the automated payload mission planning and handling of user emergency orders. In addition, the approach applied for supporting TT&C station scheduling and orbit maintenance activities will be presented. Finally, a summary of the overall ground segment will be provided and the Sentinels Flight Operations Segment specific facilities, based on extensive use of ESA/ESOC ground software infrastructure, presented.

The Baltic Sea is subject to various European environmental regulations which aim at securing its long-term protection. This will be achieved by the accompanying monitoring programmes associated with, for example, the HELCOM convention, the EC water framework directive, the natura 2000 Directives and the upcoming European maritime policy, to name the most important regulatory policies. These monitoring programmes demand large scale, frequent and accurate measurements of physical, biological and chemical parameters. GMES (global monitoring for environment and security) is a major activity of the European Union and Commission which aims at providing operational services by making the best use of spaceborne earth observation data, in-situ observations and models. MarCoast is the GMES service element project addressing the marine environment and is funded by the European space agency. MarCoast is providing marine and coastal services for international, regional and national end users. The project is driven solely by these end users, which include mainly public bodies in charge of the marine environment, such as, for example, the European environmental agency (EEA), the European maritime security agency (EMSA) or the German federal and maritime hydrographic agency (BSH). The MarCoast service portfolio includes oil spill detection and polluter identification as well as water quality products and services. The latter comprises monitoring the water quality with respect to European regulations as above, monitoring and alerting of algal blooms and the monitoring of large scale water quality indicators. The production chain of MarCoast begins with ENVISAT MERIS and Aqua MODIS data for the ocean colour products and AATSR data for sea surface temperature. The satellite data are downloaded from the space agencies and routinely processed to provide basic data sets of key parameters on a common grid. A merged MODIS and MERIS data product is produced at 1km. MERIS Full Resolution data (300m) complement the basic data. The service providers combine the basic data with in-situ data, integrate them into forecasting models or perform data analysis and statistical evaluation. Validation plays a key role for the acceptance of the satellite derived products by the end users. The accuracy of the products and the reliability of the service are regularly evaluated by the Validation Bureau, which is an independent entity within the project.

Strategic discussions among EEA member countries and the main EU institutions responsible for environmental policy, reporting and assessment have underlined an increasing need for quantitative information on the state of the environment based on timely, quality-assured data, concerning in particular land cover and land use. Based on these requirements EEA is collaborating since 2006 with the European Commission (EC) and the European Space Agency (ESA) on the implementation of a fast track service on land monitoring in line with the communication: “Global Monitoring for Environment and Security (GMES): From Concept to Reality” [1]. CORINE Land Cover 2006 is the third European Land Cover inventory (1990, 2000 and 2006). The number of participating countries is increasing, at present being 39. The project is co-financed by the EEA and the member countries, and covers 5.8 Mkm2. Results will be freely available on the Internet. A Technical Team working under the ETC-LUSI (European Topic Centre Land Use and Spatial Information) is responsible for technical follow-up of the project, i.e. training of national teams and verification of results. National teams use multi-temporal SPOT-4/5 and IRS-P6 imagery to derive the minimum 5 ha land cover changes that occurred between 2000 and 2006. Particular emphasis is placed on mapping the real change processes. National teams usually have access to recent topographic maps and high-resolution digital orthophotos as in-situ data. CLC2006 is produced by combining CLC2000 and CLC-Changes in a GIS.

Sentinel-2: ESA's Optical High-Resolution Mission for GMES Operational Services

A web-based distributed system for monitoring and forecasting of the marine environment has been developed in line with INfrastructure for SPatial InfoRmation in Europe (INSPIRE) and Global Monitoring for Environment and Security (GMES) recommendations for a European Spatial Data Infrastructure (SDI). This system, called DISPRO, enables integration and distribution of multi-source data from satellites, aircraft, and in situ instruments, as well as results from numerical models. Geographic data and metadata are stored on a set of distributed computer nodes and retrieved and integrated by a web GIS client by means of Open Geospatial Consortium (OGC) Web Map Server (WMS) technologies. A profile of ISO 19115 was developed for metadata handling, using eXtensible Markup Language (XML) as a platform independent encoding mechanism. DISPRO has been demonstrated in six European coastal zone and ocean regions in the spring and summer of 2005. The overall positive experiences of both service providers and end users indicate that the system should be further developed into an operational GMES service.

Global Monitoring for Environment and Security (GMES) is a joint initiative of the European Community and of the European Space Agency. The Declaration on the GMES Space Component Programme provides that the Sentinel-5 Precursor mission is planned to be implemented in cooperation with the Kingdom of the Netherlands, which in the frame of the development of the TROPOMI Instrument, will provide the Ultraviolet-Visible-Near-Infrared instrument as a national contribution. The Sentinel-5 Precursor is a UV-VIS-NIR-SWIR spectrometer atmospheric chemistry mission derived through tailoring of Sentinel-5 specifications with priority on spectral resolution, coverage, spatial sampling distance, signal-to-noise ratio and only high priority bands.

The objective of the Global Monitoring for Environment and Security (GMES) is to provide, on a sustained basis, reliable and timely services related to environmental and security issues in support of public policy makers' needs. MyOcean is the implementation project of the GMES Marine Core Service (MCS), aiming at deploying the first concerted and integrated pan-European capacity for Ocean Monitoring and Forecasting (www.myocean.eu.org). MyOcean develops upgraded European capabilities for reference marine information and provides a wide range of key ocean indicators. The MCS provides information to intermediate users who combine it with other forms of information and data to provide customized downstream services for end users. The end users range from wide public to special target groups. Downstream marine services in Estonia are built on in-situ real time and near real time measurements, satellite remote sensing imagery and numerical modeling. Two-day marine forecasts for the North-Eastern Baltic Sea are produced by 3D circulation model HIROMB-EST. The downstream service portfolio consists of following items. Real time sea level observations including history and two-day forecasts on 12 locations around the Estonian coast are available in the Internet. Sea surface temperature (SST) and salinity are complimented with near real time ferry-box observations on the cross-section between Tallinn and Helsinki. During cloud free sky SST charts are produced using MODIS (Moderate Resolution Imaging Spectroradiometer) imagery for the Gulf of Finland and Gulf of Riga. Illegal oil spills are detected from SAR imagery. The drift of the slick is simulated by Seatrack-Web and potential polluters are identified combining Seatrack Web and the Automatic Identification System (AIS). The monitoring of suspended particulate matter during harbor dredging is based on MODIS and MERIS (MEdium Resolution Imaging Spectrometer) data. The laboratory analyses of water samples are used for the calibration and validation of satellite products. The in situ measurements of vertical profiles of absorption and attenuation coefficients are used to determine the profiles of particle origin, concentration and size distribution. Operational ice extent monitoring using SAR data is rather widespread. Optical remote sensing imagery from MODIS and MERIS sensors complement SAR imagery. Ice concentration maps are produced using the histogram analysis of MODIS 250 m reflectance data. This data is used for model evaluation with the purpose to get reliable ice forecast from the HIROMMB-EST model. Spectral optical remote sensing data from MERIS helps to identify different ice types. The determination of high spatial resolution marine and coastal wind from the Advanced Synthetic Aperture Radar (ASAR) is quite a novel application in the Estonian waters. Wind field data can be retrieved from ASAR C-band data and model results using CMOD algorithm.

In the frame of the Global Monitoring for Environment and Security (GMES) program ESA is currently implementing the Sentinel-3 mission [3], [4]. It is designed as a constellation of two identical polar orbiting satellites, separated by 180 deg, for the provision of long-term operational marine and land monitoring services. These services include the generation of land and ocean colour products, sea and land surface temperature, vegetation products and sea, ice and land surface topography. With a planned launch in 2013 of the first satellite, the Sentinel-3 mission will provide valuable information for scientists and policy makers in the European Union and its Member States for the next decades. The operational character of this mission implies a high level of availability of the data products and fast delivery time, which have been important design drivers for the mission.

With the European Space Agency's (ESA) Sentinel‐1A satellite expected to enter into its operational phase later this summer, it ushers in a new series of Earth observation satellites. The first generation of the fleet of satellites, which will total 20 when all are launched, will comprise “the most comprehensive Earth observation system worldwide,” according to Josef Aschbacher, head of program planning and coordination for ESA's Earth Observation Programs directorate. The satellites are a key part of Copernicus, the European Earth Observation Program that from 1998 to 2012 was called the Global Monitoring for Environment and Security (GMES) program.

The ESA Sentinels constitute the first series of operational satellites responding to the Earth observation needs of the EU-ESA Global Monitoring for Environment and Security (GMES) programme. The GMES space component relies on existing and planned space assets as well as on new complementary developments by ESA. This paper describes the Sentinel-1 mission, an imaging synthetic aperture radar (SAR) satellite constellation at C-band. It provides an overview of the mission requirements, its applications and the preliminary technical concept for the system.

In the framework of the Global Monitoring for Environment and Security (GMES) pr ogramme, the European Space Agency (ESA) in partnership with the European Commission (EC) is developing the SENTINEL-2 optical imaging mission devoted to the operational monitoring of land and coastal areas. The Sentinel-2 mission is based on a twin satellites configuration deployed in polar sun-synchronous orbit and is designed to offer a unique combination of systematic global coverage with a wide field of view (290km), a hi gh revisit (5 days at equator with two satellites), a high spatial resolution (10m, 20m and 60 m) and multi_spectral imagery (13 bands in the visible and the short wave infrared spectrum). SENTINEL-2 will ensure data continuity of SPOT and LANDSAT multispectral sensors while accounting for future service evolution. This paper presents the main geomet ric and radiometric image quality requirements for the mission. The strong multi-spectral and multi-temporal registration requirements constrain the stability of the platform and the ground processing which will automatically refine the geometric physical model through correlation technics. The geolocation of the images will take benefits from a worldw ide reference data set made of SENTIN EL-2 data strips geolocated through a global space-triangulation. These processi ng are detailed through the description of the level 1C production which will provide users with ortho-images of Top of Atmosphere reflectances. The huge amount of data (1.4 Tbits per orbit) is also a challenge for the ground processing which will produce at level 1C all the acquired data.

Atmospheric pollution due to carbon dioxide emission from different fossil fuels and deforestations are considered as a great and important international challenge to the societies. This study is to investigate carbon dioxide (CO2) distributions in selected points in Nigeria using neural network. Neural network model were used to estimate daily values of carbon dioxide, study spatial temporal variations of carbon dioxide, and study the annual variations of estimated and observed carbon dioxide in Nigeria. The study areas used in this work are thirty six (36) points location over Nigeria. The data used in this work is a satellite carbon dioxide () data were obtained from Global Monitoring for Environment and Security (GMES) under the programme of Monitoring Atmospheric Composition And Climate (MACC) www.gmes-atmosphere.eu/data between 2009-2014. The neural network architecture used comprises of three main layers; an input layer, a hidden layer and an output layer. Four input data were considered which include year, day of year (DOY) representing the time, latitude and longitude. Twenty hidden neurons were employed, while the output is the desired data of carbon dioxide. The results show that the increase in trend of CO2 in dry season in every part of the country is on yearly bases. In the wet season, the concentration of CO2 in Nigeria is not as much as in the dry season case, probably due to absorption of the gas by precipitation. The continuous annual increase of CO2 distribution suggests continuous increase of the greenhouse gas in Nigeria. This reveals continuous contribution of CO2 in Nigeria. The similarity in the estimated and observed signatures reveals that neural network model performance were excellent and efficient in determination of spatial distribution of CO2, thereby proving to be useful tool in modeling the greenhouse gases. The results show that neural network model has the capacity of investigating greenhouse gases variations in Nigeria.

Socio‐Economic Benefits From the Use of Earth Observation; Ispra, Italy, 11–13 July 2011 Many large space‐or ground‐based Earth observation systems, such as Global Monitoring for Environment and Security (GMES) and Landsat, are justified by citing their benefits to scientific knowledge and their impacts on government decisions about environmental issues. These justifications attempt to quantify the lives saved, losses avoided, or economic benefits gained. Each justification is made on an ad hoc basis, and the approach used in one case rarely applies to another. In July 2011 a workshop was held at the European Commission Joint Research Centre in Italy to consider whether broadly applicable methodologies could be developed that could be consistently used for assessing the value of large‐scale observation and information systems.

Since 1991, along track scanning radiometers (A)ATSR have been flown on a series of satellite platforms. These instruments use an along-track scanning design that provides two views of the same earth target through different atmospheric paths. Dual-view multispectral measurements can be used to derive an accurate atmospheric correction when retrieving geophysical parameters such as Sea Surface Temperature (SST). In addition, the (A)ATSR family of instruments use actively cooled detector systems and two precision calibration blackbody targets to maintain and manage on-board calibration. Visible channel calibration is implemented using a solar diffuser viewed once per orbit. As a consequence of these design features, resulting data derived from (A)ATSR instruments is both accurate and well characterized. After 10 years of Service the ENVISAT platform was lost in early 2012 asnd AATSR operations stopped. The Global Monitoring for Environment and Security (GMES) Sentinel-3 “Sea Land Surface Temperature Radiometer“ (SLSTR) instrument is the successor to the AATSR family of instruments and is expected to launch in April 2014. The challenge for SLSTR is to develop and deliver a new instrument with identical or improved performance to that of the (A)ATSR family. The SLSTR design builds on the heritage features of the (A)ATSR with important extensions to address GMES requirements. SLSTR maintains the main instrument principles (along-track scanning, a two point infrared on-board radiometric calibration, actively cooled detectors, solar diffuser). The design also includes more spectral channels including additional bands at 1.3 and 2.2 μm providing enhanced cloud detection, dedicated fire channels, an increase of dual view swath from 500 to 740 km, an increase in the nadir swath of 1400 km. The increase in swath has led to, a new optical front-end design incorporating two rotating scan mirrors (with encoders to provide pointing knowledge) and an innovative flip mechanism to select a specific optical chain. Unavoidably, these improvements introduce complexity, risk, increased mass and power. Bearing these aspects in mind, this paper reviews the design and performance of the Sentinel-3 SLSTR.

A global climate observation system is essential to improve our understanding of the climate system and our ability to anticipate trends. This article addresses the criteria that such a system must meet, and the range of observation techniques which must be implemented. Observations collected by satellite must be calibrated, validated and supplemented by surface and subsurface measurements in the atmosphere, the ocean and on land. All these observations need to be used in conjunction with numerical models and data distribution networks, and maintained in a complex of centres for archiving and reprocessing of environmental data. A global effort is required to meet these challenges, based on intensive international cooperation. The article describes activities in Europe and elsewhere, among them the World Weather Watch of WMO, the European initiative GMES (Global Monitoring for Environment and Security), and particularly the GEOSS (Global Earth Observation System of Systems), developed in the intergovernmental framework of GEO (Group on Earth Observations) to overcome obstacles of all kinds and achieve the objectives of a global climate observing system.