Space Weather Watchers Warn of Geomagnetic Storms

GOLDEN, Colorado, January 3, 2000 (ENS) - Geomagnetic storms that could cause power blackouts, disruptions in communications and satellite failures are predicted for early this year, according the U.S. Geological Survey, the United States agency primarily responsible for tracking geomagnetic activity.

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Two ejections of matter from the Sun's corona, pictured here, were observed on New Year's Day. Neither one was directed at Earth. (Photo courtesy NASA)
When charged particles from the Sun collide with the Earth's magnetic field geomagnetic storms arise. The U.S. Geological Survey (USGS) says the next peak in sunspot activity is expected to occur in early 2000. Magnetic storms are not rare, but great storms like the one forecast for early this year are, says Don Herzog, a USGS geophysicist.

It is geomagnetic storms that produce beautiful Northern lights, but they can also pose a serious threat for commercial and military satellite operators, power companies, astronauts, and they can even shorten the life of oil pipelines in Alaska by increasing pipeline corrosion, the USGS warns.

Earth’s magnetic field can undergo large and rapid fluctuations due to the interaction of charged particles ejected by the Sun that collide with the geomagnetic field. These solar ejections, traveling at more than a million miles an hour, are associated with sunspots which increase and decrease over an 11 year cycle. The number of geomagnetic storms also increases and decreases in concert with that 11 year cycle.

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Solar eruption (Photo courtesy NASA/JPL)
"During the sunspot maximum we are going through now, smaller storms can occur rather frequently - even several times a week," said Herzog.

The last great magnetic storm occurred exactly 11 years ago this coming March 13 at 3 am EST. That storm caused the collapse of the Hydro-Quebec power system in Canada, leaving about six million people without power. If the storm had struck a few hours later than it did, the blackout would likely have been much worse because of the heavier power consumption during daytime hours.

The National Aeronautic and Space Administration (NASA) produces daily forecasts on the likelihood of a major solar flare. These predictions are charted on the NASA Spaceweather website: http://www.spaceweather.com/

NASA said today the Earth's magnetic field, "remains unsettled in response to a high speed solar wind stream." The source of the solar wind, a large coronal hole, has rotated past the sun's central meridian. As a result the disturbances should begin to subside today and tomorrow, NASA observers said.

"The sun's been doing this for a long, long time," said Dr. David Hathaway, solar physics group leader at NASA's Marshall Space Flight Center. And even though the sun is climbing towards the peak of yet another sunspot cycle maximum, "This cycle is a little different from what we've seen, but not out of the ordinary. For us on Earth it's going to be life as usual.

"The big difference for us is our increasing dependence on technology in general and on space-based technology in particular. Certainly it's not going to wipe out the planet although it may affect a satellite or two," Hathaway said.

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This Extreme Ultraviolet image of the Sun from the SOHO spacecraft shows a dark coronal hole west of the central meridian. High speed solar wind particles from the hole caused moderate geomagnetic disturbances on Earth beginning December 31, 1999. (Photo courtesy NASA)
The USGS operates a network of 13 magnetic observatories that continuously monitor the Earth’s magnetic field. The USGS provides this valuable geomagnetic data to a wide variety of users and organizations that can be affected by a geomagnetic storm. The data are collected in near-real time via satellite to a downlink center located in Golden, Colorado. They are then sent to the U.S. Air Force (USAF) Space Command Center for use in their operational models that characterize the near-space environment surrounding the Earth, and to NOAA’s Space Environment Center for distribution to their extensive customer list.

The geomagnetic data are also shared with agencies comparable to the USGS in other countries including Canada, Japan, France, Brazil, the United Kingdom, and others as part of an international organization called INTERMAGNET. These agencies also share their information with the USGS.

Data at various Geomagnetic Information Nodes are received via the GOES-East and GOES-West satellites (United States and Canada); METEOSAT (Edinburgh and Paris); and GMS (Japan).

The data are made available on the Internet at: http://geomag.usgs.gov and by email request from the website.

The USGS produces models of the Earth’s magnetic field that are used in military and civilian navigational systems and in research for studies of the effects of geomagnetic storms on the ionosphere, atmosphere, and near-space environment.