Coronal mass ejection

From Glossary of Meteorology



coronal mass ejection

(Abbreviated CME.)

A space weather term describing the expulsion of plasma from or through the solar corona. CMEs are often, but not always, associated with erupting prominences, disappearing solar filaments, and/or solar flares. CMEs vary widely in structure, density, and velocity. Large and fast CMEs occasionally are directed toward Earth and can result in geomagnetic storms. Strong CMEs provide the best chances for periods of severe or extreme geomagnetic storm events and can cause damage to the electrical power grid. The fastest CMEs can initially travel at speeds near 3000 km s−1.

Space Weather Prediction Center, 2018: Coronal mass ejections. Accessed 13 August 2018. Available at https://www.swpc.noaa.gov/phenomena/coronal-mass-ejections.


Term edited 13 August 2018.


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