Atmospheric noise

CCIR 322 atmospheric noise relationship.[1] The standard has tables and maps that determine the noise figure at 1 MHz according to the season and the time of day. This graph converts that noise figure to other frequencies. Notice that the plotted lines are spaced in 10 dB increments at 1 MHz.

Atmospheric noise is radio noise, or "static", caused by natural atmospheric processes, primarily lightning discharges in thunderstorms. On a worldwide scale, there are about 40 lightning flashes per second, or ≈ 3.5 million lightning discharges per day.[2]

  1. ^ Cite error: The named reference CCIR-322 was invoked but never defined (see the help page).
  2. ^ "Annual lightning flash rate map". Science on a Sphere. sos.noaa.gov. Datasets. National Oceanographic and Atmospheric Administration (NOAA). Archived from the original on 24 March 2014. Retrieved 15 May 2014.