LOS ANGELES —  A new computer model suggests the next solar cycle will be more active than the previous one, potentially spawning magnetic storms that will be more disruptive to communication systems on Earth.

The next sunspot cycle will be between 30 percent to 50 percent more intense than the last one, scientists said Monday.

The cycle will also begin a year later than expected, in late 2007 or early 2008, and peak around 2012, said Mausumi Dikpati of the National Center for Atmospheric Research in Boulder, Colo.

The new prediction is at odds with previous forecasts, which suggested that the intensity of the next solar cycle would be measurably smaller.

Accurately predicting the intensity of the sunspot cycle, which occurs about every 11 years, allows scientists to anticipate solar storms. They are caused by solar flares, or giant eruptions that burst from the surface of the sun.

Solar storms, which eject billions of tons of plasma and charged particles into space, can produce dazzling northern lights, but also disrupt power lines, radio transmissions and satellite communication.

The last time the solar cycle peaked was in 2001. During the last cycle, solar storms caused extreme radio blackouts in the Pacific.

For decades, scientists have tracked the solar cycle and appearance of sunspots, but they have been unable to accurately predict the intensity or timing of solar storms, which increase as the number of sunspots increases.

Dikpati, of the National Center for Atmospheric Research, said her team tested the new computer model using previous solar cycle data and had 98 percent accuracy.

David Hathaway, a solar astronomer with NASA's Marshall Space Flight Center in Huntsville, Ala., does not doubt that the next sunspot cycle will be stronger than the previous one.

But Hathaway said his own research suggests that the next cycle will occur late this year — earlier than what Dikpati predicted.

The current research, funded by National Science Foundation, is published in the latest Geophysical Research Letters.