 The higher a system's SNR the better it is at discriminating actual targets from noise signals.Clutter refers to radio frequency (RF) echoes returned from targets which are uninteresting to the radar operators.Such targets include natural objects such as ground, sea, and when not being tasked for meteorological purposes, precipitation (such as rain, snow or hail), sand storms, animals (especially birds), atmospheric turbulence, and other atmospheric effects, such as ionosphere reflections, meteor trails, and Hail spike.