Climate Exchange

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Understanding climatic processes on Earth:

the invaluable contribution of satellites

Volker Liebig, Director Earth Observation, European Space Agency

arth is a complex planet: the only one known today that

carries life – in abundance and for billions of years.

Powered by the interplay of its spherical, hot inner struc-

ture and energy received from outside, particularly from the

sun, various spheres of the planet make up the environment we

live in: atmosphere, oceans, land and cryosphere.

Climatic change processes have accompanied most of Earth’s exist-

ence. Today, however, these changes take place at – so far as can be

said from scientific sources – unprecedented speed. Human actions

could be a direct cause of some accelerated climatic phenomena,

like an unusually strong warming of the Arctic or an increase in

frequency of extreme weather events around the globe.

With eight billion humans on the planet, the question of efficient

mitigation of negative climatic consequences, and of a more sustain-

able way of acting, has become imperative. But both the assessment

of the current situation and the planning of the future necessitate

a sound scientific collection of Earth-related data, as well as their

careful interpretation to become the basis of societal

consequences.

Just as the cartographers of earlier centuries climbed

mountains to have a better overview over their

surroundings, satellites in space get a better picture of

our planet at large. It is not only photographs of the

Earth’s surface that scientists are looking for; much

more can be achieved through more sophisticated satel-

lite applications. The fleet of those sentinels in space

helps us to better understand global processes that

shape our environment and also our future.

Nothing within the Earth’s systems is an isolated

event. When it comes to mapping and understanding

climate change processes complex questions arise, also

impacting political and scientific debate. The impact of

observed or forecasted variations of our environment is

far-reaching. It is imperative to provide a basis to put

factual evidence, scientific models, social debate and

cosystems

The most accurate geoid delivered by the GOCE mission

Source: ESA 2012