Sea Clutter
When smooth, the sea does not back scatter appreciable
energy, but under disturbed conditions echoes may observed. These come because the radar is detecting energy from the side lobes due to the ocean waves. The
occurrence of sea clutter is dependent on a wind and wave conditions
and is not always seen in the same area. Echo coverage is confined to ocean areas; there is no impact on land
QPF or hydrological analyses. Radial velocities are lower than the winds,
as they are influenced by the wave motion. Sea clutter is not troublesome
in the manner of a permanent echo as the signal strength is low and a
slight increase in elevation usually reduces it below receiver
threshold.