Volker Liebig took up duty as Director of Earth Observation Programmes(D/EOP) and Head of ESRIN in October 2004. ESRIN, ESA’s centre in Italy, is situated in Frascati near Rome.

From the very foundation of the European Space Agency, Earth Observation has been a major priority for ESA. Could you tell us a little about ESA's Earth Observation programme?

Climate – atmosphere, hydrosphere, cryosphere, land masses, anthropogenic influences and more – has since the beginning of space-based Earth observation been a central observation target. The first satellites of the European Space Agency end of the 1970s were meteorological missions (Meteosat series), which opened a wide range of applications and laid foundation of meanwhile over 30 years of operational weather monitoring and forecasting. Today continued with the Meteosat Second Generation missions (Meteosat Third Generation is under development by ESA for deployment as of 2015 onwards) this European effort provides a stable basis for European meteorological observations. With the launch of ERS-1 in 1991 started the era of multi-purpose ESA Earth observation missions, continued with ERS-2 in 1995 (still functional today) and Envisat in 2002. These “workhorses” in space provide steady data streams for a great variety of applications and services, from ice monitoring to fishery, from deforestation to emergency relief operations. But in addition, data from these ESA missions are used for scientific purposes by meanwhile more than 3000 project teams around the world. A better understanding of functions and interactions of the various spheres of Earth as well as the role humans play therein is a central part of both data gathering and scientific analysis. In complementing ESA’s efforts to better understand system Earth and its subsystems, the scientific ESA Earth Explorer missions – specialised satellites focusing on themes of scientific interest and urgency – complement our observation portfolio. Climate development, climate change and the anthropogenic element therein play an important role in the selection of Earth Explorers. The first of the Explorers, GOCE (Global Ocean Current Experiment), a mission to map the Earth’s gravity field in unprecedented accuracy, has been successfully launched in March 2009. The aim is to have a gravity field exact enough that ocean currents can be detected from satellite radar altimeter measurements of the sea surface. The second mission, SMOS (Soil Moisture and Ocean Salinity mission), was brought into space in November 2009. Both soil moisture and ocean salinity are important parameters of climate change models and can be used for many applications. ESA’s Ice mission Cryosat will be launched in a few weeks from now, on 25 February 2010. It will measure not only the ice extent at the poles but also the ice thickness. Another four Explorers are under development. These missions are selected and developed in closest cooperation with the scientific community to allow translating science needs directly into space-based instruments. Besides our scientifically oriented Earth Explorers, ESA is currently developing a suite of modern operational missions, the Sentinels, within the frame of the GMES (Global Monitoring for Environment and Security) initiative. All in all, we have more than 20 satellites to be launched over the next ten years, which makes ESA’s Earth Observation Programme the most dynamic and complex worldwide.

The Global Monitoring for Environment and Security (GMES) initiative has been very important to Europe. Why is it important to achieve an autonomous and operational Earth observation capacity?

Autonomous access to information about environment, climate change and security is a necessity for Europe. The optimum definition of policies of the EU and European nations in fields like environment, agriculture, resource management, land management, coastal waters surveillance, maritime traffic monitoring etc. brings social and economic benefits. Only with good information we can take well informed decisions. To understand the importance of GMES, we have to bear in mind that Earth Observation has an enormous potential not only for science and research, but also for daily life. In order to incorporate space-based data into daily services for you and me, we need one thing: sustainability. That means we need to guarantee a constant and consistent stream of data, which in return asks for reliable satellite missions, proven technology and a well-functioning ground station network and data distribution through service providers. All this is about to be established in Europe with GMES. GMES is about collecting data, mainly Earth observation data, from satellites and from in-situ measurements, combining it with socio-economic data, and processing them to generate services supplying readily usable information. ESA, in accordance with the European Space Policy (ESP), has taken responsibility for the GMES Space Component: That is the coordination of European satellite infrastructure and the establishment of the Sentinel missions, to continue current Earth Observation efforts and avoid any observation gaps in fields of high relevance. GMES is one of the most ambitious and encompassing programmes ever undertaken, and a cornerstone of European space ambitions. With GMES we want to achieve for environmental observations what we reached for meteorology 30 years ago – to build an operational and sustainable satellite monitoring system.

EO plays an important role in monitoring our changing climate. Throughout last year, climate change was highlighted in the political arena ranging from the Members of Parliament meeting just before IAC 2009 in Daejeon to the COP15 meeting in Copenhagen. Is it important for politicians as well as scientists to be engaged in this process?

We need both of them, scientists and politicians. Whereas scientists can tell us about the reasons, effects and extent of climate change, as well as the human impact thereon, politicians can drive the process of mitigating and combating climate change. The latter requires actions, guidelines, coordination and sufficient financial resources. It is important to see that science and politics are not two separated domains, especially not in the climate change debate. For example, the importance of global observation for understanding climate change has triggered action on the international scene. A “Global Climate Observing System” (GCOS) was established in 1992 to ensure that the high-quality observations needed to address climate-related issues are obtained and made available to all users. To meet this goal, GCOS defined a set of about 44 “Essential Climate Variables” (ECVs), which shall be systematically monitored, in order to quantify the state of our climate in an objective and effective way. ESA has reacted to this challenge and has launched in 2009 a new programme, the ESA Climate Change Initiative. It aims at using earth observation data records to systematically generate relevant ECVs. Besides the complex effort of keeping our vast data archives up to date (some 3300 Terabytes of data archived since 1986), we also need to ensure that full capital is derived from ongoing and planned missions. Through a “feedback loop” new user feedback and the latest scientific knowledge (e.g. the new geoid model derived from GOCE) are brought together. Like this we hope to respond to the increasingly urgent needs of the international climate change community. Through its Earth observation missions in conjunction with the Climate Change Initiative, ESA is developing climate-quality observing systems, providing free access to the worldwide science community, and working with its partners to ensure long-term observations of fundamental climate data records. I would like to add that the challenge we are facing is not only a challenge for scientists and politicians, but for every single one of us. Whereas scientists may give explanations and politicians show directions, we all can contribute a great deal by a conscious and responsible life style.