The Full Picture

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threats linked to climate change, such as wildfires and floods, which can

adversely affect human health, property and infrastructure, and natural

ecosystems.

A virtual constellation of satellites monitoring atmospheric compo-

sition and behaviour would measure concentrations of various gases

and aerosols above the Earth’s surface; such measurements are critical

to understanding global change. These satellites could also be used to

monitor severe environmental phenomena worldwide. In 2006, for

example, widespread fires and their smoke plumes in Africa were

mapped by European and American satellites, while the height of the

plumes was measured by a joint US-French satellite mission. Data gath-

ered by these different satellites were combined and used to predict

how the particulates in the smoke would disperse across land masses

and oceans. This information was then used by authorities to prepare

public warnings, increase the effectiveness of emergency responders

and assess environmental impacts.

A virtual constellation of satellites monitoring precipitation would

enable national authorities to track the seasonal progression of rainfall

patterns, better understand the development, movement and impact

of severe storms such as typhoons and hurricanes, and identify areas

likely to experience intense, rapid flooding. Such a virtual constella-

tion could improve forecast and warning services provided by national

weather agencies to better protect lives and property.

Oceans cover more than three-quarters of the Earth’s surface and play

an integral part in its climate system. A virtual constellation of satellites

focused on ocean dynamics would gather data critical to

monitoring sea level rise and the threat it poses to coastal

communities worldwide. Such a constellation would

gather information about ocean temperature and chem-

istry, and possible changes in ocean currents. It would also

be vital for use in tracking and predicting the behaviour of

tropical storms that form over ocean waters with the

potential to threaten coastal communities and ecosystems.

And it would provide information essential to under-

standing the scope and pace of climate change.

The Earth system is complex and changing rapidly.

Virtual constellations of satellites, unified in their focus

through international coordination, have the potential to

provide policy makers with vital, integrated and readily

available information about natural hazards, climate

change, and societies’ impact on that system. Information

that efficiently coordinated and effectively deployed satel-

lites gather can also help to protect lives and property and

assist decision makers in better managing and protecting

the Earth’s precious resources.

The concept of coordinated teams of satellites working

together will hopefully lead to the implementation of real,

physical constellations of satellites, flying in coordinated

orbits to monitor, assess and forecast changes in the atmos-

phere, oceans and terrestrial environment. It is clear that

a new period of integrative and collaborative effort has

begun in the area of Earth-observing satellites and climate

change research. With the continued support of CEOS to

develop and deploy space assets as part of the GEOSS, the

global Earth-observation community is effectively refo-

cusing its efforts. The member agencies of CEOS are

committed to this unprecedented effort to better coordi-

nate observing systems and human expertise to provide

government decision makers with a better understanding

of the Earth system.

Rising sea levels worldwide will impact islands

and coastal regions such as Mumbai, India

Source: European Space Agency

Torrential rains and flooding affected millions in Bangladesh in

June 2007

Photo: AP

GEOSS C

OMPONENTS

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