ESA celebrates 15 years of near-real time data delivery in Earth Observation (Forwarded)

ESA News
http://www.esa.int

16 February 2007

ESA celebrates 15 years of near-real time data delivery in Earth Observation

Decision-makers, scientists and local authorities require up-to-date
environmental information in order to manage natural resources, respond to
natural disasters and better understand climate change. ESA has been
responding to this requirement since 1992 by offering data from
Earth-observing satellites in near-real time to allow users to study and
monitor the current state of the oceans, lands, atmosphere and cryosphere.

At the end of the commissioning phase of ESA's ERS-1 satellite in early
1992, the space agency began disseminating oceanographic data of the
satellite's onboard instruments to users through a network of landlines.
Many of these data were re-formatted in near-real time for compatibility
with end-users connected to the World Meteorological Organisation (WMO)
network.

A few months later, ESA implemented an innovative system allowing some users
to receive data through small dish antennas. This system, called Broadband
Data Dissemination Network (BDDN), was based on telecommunication satellites
broadcast. During this period, only data of small volume were delivered in
near-real time (i.e. within three hours), while data of larger volumes took
nearly 24 hours to be delivered.

As the need for timely information increased for environmental forecasting
and disaster response, ESA sought to speed up its data flow by making use of
emerging technologies. By the time ESA launched ERS-2 in 1995, the space
agency was readily using the Internet to deliver data from more
sophisticated instruments, such as the Global Ozone Monitoring Experiment
(GOME).

Responding to the growing demand for ozone data to monitor the ozone layer
and improve ultraviolet (UV) radiation forecasts, ESA began using the GOME
instrument aboard ERS-2 to maintain a regular census of global stratospheric
ozone levels. Since 1997, the sensor has been delivering near-real time data
on ozone levels to users. It also provides coverage of other trace gases, UV
and air-pollution monitoring.

The need for near-real time data delivery has continued to increase over the
last 10 years as a consequence of the incredible progress in Information
Technology; the power of computers and the growth in network bandwidths and
storage capacities have resulted in Earth observation (EO) users requesting
larger volumes of data to be delivered in unprecedented time frames.

In an effort to meet these demands and deal with the vast amount of
near-real time data produced by Envisat, the world's largest Earth-observing
satellite launched by ESA in 2002, ESA upgraded its data delivery method to
the quicker Data Dissemination System (DDS), which also uses
telecommunication satellites. In addition, as the ESA mandate for delivering
EO data expanded to non-ESA missions (Third Party Missions), the various
European centres delivering EO data were interconnected through large
communication networks.

Fifteen years later, there are many established services requesting
near-real time EO data delivery. For example, utilising data from Envisat's
Advanced Along Track Scanning Radiometer (AATSR) instrument, as well as
other instruments aboard different satellites, daily sea surface temperature
maps of European seas are made available as part of the agency's
Medspiration project. Because the AATSR instrument has an unprecedented
spatial resolution of two square kilometres, the maps also allow for
detailed features like eddies, fronts and plumes to be detected.

Today's Earth check-up provides access to daily worldwide fire maps, UV
radiation levels, ozone forecasts and daily sea surface temperatures.

The latest ESA near-real time capability added to the Earth check-up is
MIRAVI, short for MERIS Images RApid Visualisation. MIRAVI, which debuted
last December, allows people unfamiliar with EO data to track natural events
in progress, such as fires, floods and volcanic eruptions, or simply explore
the planet through the eyes of a satellite. Although the MIRAVI images are
fascinating and provide the marvellous feeling that users are 'onboard the
satellite', scientists prefer to use the complete MERIS products, which are
also available through near-real time servers, for research purposes.

Just as ESA has met the growing number of users and requests for data from a
few gigabytes transmitted per day in 1992 to 400 gigabytes delivered daily
in 2007, it will continue to develop and exploit new technologies to meet
the rising demands of near-real time Earth data from space.

In the next months, ESA will further expand its range of EO data available
in near-real time to scientists by allowing them easy access to large
amounts of Synthetic Aperture Radar (SAR) and MERIS data, particularly over
Europe.

[NOTE: Images and weblinks supporting this release are available at
http://www.esa.int/esaCP/SEM148BE8YE_index_1.html ]