A suloy is an unusual state of the sea where the surface is covered by precipitous and irregular
waves that form either (1) in lines at a convergence, (2) in curved boundaries of eddies, or
(3) in rounded patches of water (Fedorov, 1983). The term was coined by a Soviet oceanographer
to describe such features in the White Sea, the huge embayment lying between Finland and the
Soviet Union. In Japan, they are known as "siomes." Suloys produce an intense hissing audible
for several miles. The noise may be loud enough to resemble a moving train in the near distance.
Underwater, a mysterious acoustic effect always accompanies them, a high-frequency sound
overriding the usual ambient noise from wind waves and swell (Monin and Krasitskiy, 1985).
Such features on the sea surface were first described in detail by Maury in his Physical
Geography of the Ocean, published in 1857. Many sea captains had logged their experiences as ships encountered
long, narrow lines of chaotic seas that sometimes created severe banging against the hull. In one report, the ship's
master hove-to while such a line of waves passed by at a speed estimated to be 100 kilometers an hour.
Our knowledge of suloys, or "lines of chaotic seas," is minimal. No quantitative
measurements have been made by Western-world oceanographers, nor are there useful estimates of their frequency
of occurrence or wave spectra, or hypotheses about their generation. There are fewer than a dozen published articles
on the subject, and those are in the Soviet literature.
Suloys of interest in space oceanography are associated with (1) converging currents
in the open ocean where the suloys mark the boundary, (2) solitons in seas and straits, and (3) eddies, either spiral
or circular. No matter what the occurrence, though, there is always a sea-surface convergence.