Active Region 1515 released an X1.1 class flare from the lower right of the sun on July 6, 2012, peaking at 7:08 PM EDT. This flare caused a radio blackout, labeled as an R3 on the National Oceanic and Atmospheric Administrations scale that goes from R1 to R5. Such blackouts can cause disruption to both high and low level radio frequencies.
Earth's magnetosphere also underwent a minor geomagnetic storm on the evening of July 6 in response to relatively slow coronal mass ejections (CMEs) that have erupted from other regions on the sun since July 4.
GCMD keywords can be found on the Internet with the following citation:
Olsen, L.M., G. Major, K. Shein, J. Scialdone, S. Ritz, T. Stevens, M. Morahan, A. Aleman, R. Vogel, S. Leicester, H. Weir, M. Meaux, S. Grebas, C.Solomon, M. Holland, T. Northcutt, R. A. Restrepo, R. Bilodeau, 2013. NASA/Global Change Master Directory (GCMD) Earth Science Keywords. Version 22.214.171.124.0