For quite some time scientific theory implicitly held the position that only electricity gridsel in high-latitude regions, e.g., the upper and lower northern and southern hemispheres (respectfully predicated) are in any danger from heavy space weather. However, a recent study’s shown that even smaller changes in space weather are magnified and exacerbated near the Earth’s equator, which means the risk is also great for electrical power grids in areas usually assumed to be well insulated from space weather.
ELECTRICITY AT RISK IN EQUATORIAL REGIONS
This sort of electrical headache is a common form of disruption in North America and Europe. But the new study reports that smaller electrical events occur in equatorial regions with a much greater frequency than previously thought.
LACK OF INFRASTRUCTURE BODES DARKLY, SANS ELECTRICITY
This represents the birth of a new threat to power grids in nations lacking extensive electricity infrastructure to counteract the effects of these electrical disruptions, which are physically caused by geomagnetically induced currents (i.e., electrical currents running between the earth and space overriding the currents of power stations).
“These disturbances affect what’s happening in the equatorial region, which has largely been overlooked. What the historical data also show is that we don’t need huge geomagnetic storms to experience the effects,” clarified Brett Carter, a visiting scholar at Boston College’s Institute for Scientific Research in Massachusetts.
Carter is also the head author of an article recently approved for publication in Geophysical Research Letters, an American Geophysical Union journal. The study mentioned above shows that electrical disruptions do not require severe geomagnetic storms to occur.
SCIENTIFIC RESEARCH
The team of researchers involved with the study analyzed 14 years of data collected in space and on earth, and concluded that the equatorial electrojet amplified geomagnetically induced currents. The equatorial electrojet is actually a naturally occurring current flowing 100 km (60 miles) above the Earth’s surface.
“We’re not talking about doomsday-style events,” continued Carter. However, the very idea of space weather effecting the surface so far from the Earth’s north and south poles is new. The equatorial electrojet has a tendency to misbehave. Carter and his colleagues discovered that small interplanetary shockwaves from the sun encountering Earth’s magnetic field can amplify this electrojet’s current.
SMALL SHOCKWAVES BIGGER THREAT
These shockwaves are far too small to trigger geomagnetic storms in higher latitudes. What this means is that equatorial space weather acts up with a much higher frequency than at higher latitudes, and the effect is felt more around electrical grids and pipelines in locales like South America, Southeast Asia, southern India and Africa.
“The reason people have not been focused on it in the past is because the large stuff usually happens afterwards,” added Carter. An interplanetary shockwave are especially a threat because of the time its taking to equip equatorial regions with instruments to study how the electrojet behaves, Carter concluded.
