Subspace surge
A subspace surge or subspace energy surge was a subspace phenomenon which could be created by cloaked vessels.

In 2371, the cloaked  created a large subspace surge, which was detected by Deep Space 9's security sensors. ()

Later that year, the , carrying Odo and Garak, detected a subspace energy surge when a Romulan warbird decloaked above the runabout. ()

In 2375, Onquanii's ship also produced a subspace surge which could be detected by 's sensors. ()

de:Subraumwelle
Subspace phenomena