Clive Cookson - Financial Times

 The Financial Times Scientists have warned satellite operators, electric utilities and airlines to prepare for disruption over the next two years as gigantic eruptions from the Sun will blast the Earth with radiation.

The 11-year cycle of solar activity is due to reach a peak in 2000 and although it has been fairly quiet so far, scientists from the US National Oceanic and Atmospheric Administration yesterday warned: ``Things are heating up.'' Solar flares of moderate intensity affected the Earth two weeks ago and again this weekend.

Ernie Hildner, director of the NOAA Space Environment Center, told the American Association for the Advancement of Science: ``The Sun is definitely ramping up and I have no doubt that we will see at least three to four episodes of stormy space weather with some adverse effects on various systems on Earth during this solar cycle.''

When the solar surface erupts, there are three possible consequences. First, the Earth's magnetic field may oscillate wildly, inducing large voltage changes in electric power systems. Secondly, radiation may damage communication satellites and pose a health risk - equivalent to as many as 100 chest X-rays -- for people flying at high altitude in polar regions. Finally, there may be a radio blackout, with serious consequences for navigation.

 In some ways human technology is more vulnerable now than at the last solar maximum in 1989, the conference heard, because there are more satellites in orbit and people are much more dependent on mobile communications. But, on the positive side, ``space weather'' forecasting is far more advanced today. NOAA and other agencies are using scientific satellites to observe the sun and measure the flow of charged particles toward Earth. They can give three-day warnings of a solar storm likely to affect Earth and a more definite 45-minute warning of severe disruption.

The private sector is also moving into space weather forecasting. The National Grid in Britain has just installed a warning system from Metatech, a US company. ``This should enable them to protect the grid in a geomagnetic storm by regulating voltages,'' said John Kappenman, Metatech project manager.

Current forecasting techniques do not give enough time for airlines to cancel or re-route flights to avoid high radiation doses. In the US, air crew are classified officially as radiation workers but there is no system for measuring their exposure, Mr Hildner said.