"Frequency noise" refers to random fluctuations or disturbances in the regular pattern or level of a sound signal. It can cause distortions or interruptions, making the sound less clear or steady. Full definition
Again, you haven't seemed to have described why getting rid of high frequency noise (and high frequency signal) is appropriate to remove the noise of weather from climate. (realclimate.org)
Based on a technology referred to as Active noise control, this technique removes the lower - frequency portions of the noise, preventing high - frequency noise from ever reaching the ear. (sonymobile.com)
It was thus quite astounding to see the vast majority of wind turbine noise measurements excluding the low frequency noise content. (wind-watch.org)