Europe aims for a new dawn in space

The European Space Agency is about to launch the first of three state-of-the-art satellites to monitor the earth's weather patterns.

According to those involved with the project, the launch will mean more accurate measurements of the earth's temperature and humidity levels as well as the amount of ozone in the atmosphere. It should improve weather forecasting and uncover more evidence about global warming.

Approximately eight minutes after launch MetOp-A will begin circling the earth and if all goes well it will then orbit the earth every 101 minutes, mapping temperature and humidity levels as it goes.

It will pass over each point on the earth's surface at approximately the same time in the morning, at 9.30 am local time, giving new insights into temperature changes over time.

While the satellite will not be able to cover such a wide area as is covered by the existing Meteosat range of satellites, which can collect data from around a quarter of the globe at a time, MetOp will provide more accurate and localised information.

Because the satellite will orbit at 800 km above the earth's surface rather than the 36,000 km for geostationary orbits like those followed by Meteosat, the data relayed to earth will be of higher quality than any satellite has previously provided.

The MetOp project's €2 billion price tag will be picked up by the European Space Agency and EUMETSAT, the European Organisation for the Exploitation of Meteorological Satellites.

The satellite will replace one of a family of US department of commerce satellites which were originally launched in the 1960s. Another of the US satellites will continue its orbit around the earth mapping afternoon conditions at 14:30 local time.

Together it is hoped the two satellites will provide the most accurate picture yet of global weather conditions.

But the co-operation with the US has not always run smoothly. After 40 years of running the project single-handedly, Washington made demands that were seen as excessive by some in the European space industry. European officials were upset by a demand by the US department of defence to create contingency plans for denying certain countries access to the information in the case of an emergency.

Originally the US had hoped to be able to shut off the information directly themselves, despite MetOp-A being controlled by OEMS. Under the compromise agreement, the US will have to submit a request to EUMETSAT for encryption to be switched on.

In the past the US department of defence has used meteorological satellites similar to MetOp-A to fine tune ballistic missile early warning radar systems.

The dispute echoed that over the EU's Galileo Satellite System when the US demanded that information to be relayed from the system should be blocked in case of a security risk. Before an agreement was reached the US had threatened to jam Galileo's signals.

With an agreement apparently reached between the various US and European agencies, the MetOp mission's organisers are looking to glean all the data possible from the new range of instruments that are attached to the satellite.

According to mission manager Eva Oriol-Pibernat the instrument that is most exiting meteorologists is the Infrared Atmospheric Sounding Interferometer, or IASI.

IASI will measure infrared emissions from the earth to calculate humidity and temperature with unparalleled accuracy. "This is the new instrument and so it is the one that every one is really looking for," said Oriol-Pibernat. "It is...a big step in respect of the data that we already have."

Another new instrument will measure wind speed over the oceans, which will immediately improve existing numerical models of weather forecasting.

The European Space Agency is about to launch the first of three state-of-the-art satellites to monitor the earth's weather patterns.

• Primary Source