美国科学家日前表示，新的计算机模型显示，下一个太阳活动周期将比先前一个太阳活动周期更加活跃，它所引发的磁暴对地球上通讯系统的破坏也将更大。

    据美联社3月6日报道，美国科学家6日表示，下一个太阳活动周期与上一个太阳活动周期相比，其强度将增加30％至50％。美国国家大气研究中心的迪科帕蒂说，下一个周期开始的时间也要比原来预计的晚1年时间，将于2007年末至2006年初开始，最高峰值将出现在2012年左右。这个关于太阳活动周期的最新预测和此前的预测有所不同。此前的预测显示，下一个太阳活动周期的强度将会较弱。

    太阳黑子的活动是周期性的，其平均周期约为11年。精确预测太阳活动周期的强度可以让科学家们提前预知太阳风暴。太阳风暴是由太阳耀斑，即太阳表面突然出现的大喷发引起的，它向宇宙空间喷射出数十亿吨的等离子体和带电粒子，并产生绚丽的北极光，但同时也会使电力线、无线电传输和卫星通讯中断。

    上一个太阳活动周期的峰值发生在2001年。在这个活动周期内，太阳风暴导致太平洋地区无线电通讯严重中断。最近几十年来，科学家一直在跟踪太阳活动周期和太阳黑子的出现。但是，他们至今仍然无法准确预测太阳风暴的强度和时间。

    迪科帕蒂说，她的研究小组利用此前太阳活动周期的数据对新的计算机模型进行了测试。测试结果表明，其准确率达到了98％。

    报道说，这项研究是由美国国家科学基金会资助的，研究结果发表在美国最新一期的《地球物理学研究快报》上。

    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.