NASA warns of impact of severe space weather on grid


Coronal mass
ejection (NASA)
Washington, DC, U.S.A. — (METERING.COM) — January 14, 2009  – Extreme weather conditions in space can have a severe impact on the electricity grid, with societal and economic costs running into billions of dollars, according to a new NASA-funded review.

The review, the summary of a recent workshop prepared by the U.S. National Academy of Sciences, points out that space weather events are driven by the magnetic activity of the sun. Besides emitting a continuous stream of plasma known as the solar wind, the sun also periodically releases magnetic energy through flares and bursts of plasma known as coronal mass ejections. When directed towards the earth these can cause large magnetic storms in the upper atmosphere, which can impact the performance of ground-based and space-borne technologies.

The main industries whose operations can be adversely affected by extreme space weather are the electric power, spacecraft, aviation, and GPS-based positioning industries, the report says. The March 1989 blackout in Quebec, in which Hydro Quebec’s power grid collapsed within 90 seconds,  and the forced outages of electric power equipment in the northeastern United States remains the classic example of the impact of a severe space weather event on the electric power industry.

One of the driving reasons for the review is that the sun is currently near the minimum of its 11-year activity cycle but solar storms will increase in frequency and intensity toward the next solar maximum, expected to occur around 2012.

While limited information is available on the societal and economic costs of severe space weather, as a proxy for disruptions caused by a severe space storm, the non-space-weather-related power blackout of August 2003 is estimated to have cost between $4 billion to $10 billion.

The report says that our knowledge and understanding of the vulnerabilities of modern technological infrastructure to severe space weather are based largely on the experience and knowledge gained during the past 20 or 30 years, during such episodes as the geomagnetic superstorms of March 1989 and October-November 2003. However, in the past there have been events of even greater severity, such as the Carrington event of 1859 – the most severe on record – and the great geomagnetic storm of May 1921, and such extreme events, though rare, are likely to occur again some time in the future.

Despite the lessons learned since 1989 and their successful application during the October-November 2003 storms, the nation’s electric power grids remain vulnerable to disruption and damage by severe space weather and have become even more so, in terms of both widespread blackouts and permanent equipment damage requiring long restoration times. According to a study by the Metatech Corporation, the occurrence today of an event like the 1921 storm would result in large-scale blackouts affecting more than 130 million people and would expose more than 350 transformers to the risk of permanent damage.

Fortunately though, there may be some warning about such an event, enabling actions to be taken to mitigate its effects and to minimize the economic impact. The report says that currently probability forecasts of space weather events can be made with varying degrees of success. For example, the occurrence probability of a geomagnetic storm or an X-class flare can be predicted with moderate confidence 1 to 3 days in advance, whereas the capability to provide forecasts of ionospheric disturbances is poor. The critical steps needed to improve forecasting capability have been identified.