Wave shoaling
effect by which surface waves entering shallower water change in wave height
In fluid dynamics, wave shoaling is the effect by which surface waves, entering shallower water, increase in wave height. It is caused by the fact that the group velocity, which is also the wave-energy transport velocity, decreases with water depth. Under stationary conditions, a decrease in transport speed must be compensated by an increase in energy density in order to maintain a constant energy flux. Shoaling waves will also exhibit a reduction in wavelength while the frequency remains constant.
In other words, as the waves approach the shore and the water gets shallower, the waves get taller, slow down, and get closer together.
Particularly in a waterbody shallow enough for its surface to be affected by its bottom and where depth contours parallel the shore, a wave packet that does dissipate its energy by breaking will rise in height as it enters yet shallower water. This is plainly evident for tsunamis as they wax in height when approaching a coastline, often with devastating results.
Overview
Waves nearing the coast experience changes in wave height through different effects. Some of the important wave processes are refraction, diffraction, reflection, wave breaking, wave–current interaction, friction, wave growth due to the wind, and wave shoaling. In the absence of the other effects, wave shoaling is the change of wave height that occurs solely by changes in mean water depth – without alterations in wave propagation direction or energy dissipation.
Begin with the source’s own compact description: “Wave shoaling” is effect by which surface waves entering shallower water change in wave height. The dossier treats that line as a proposition to test through Wave, shoaling and effect, not as a finished interpretation.
Why this record matters
The phrase “effect by which surface waves entering shallower water change in wave height” supplies a clear boundary for inquiry. It also exposes the unanswered questions: who defined that boundary, when it became stable and which sources sit outside it.
The citation trail is more important than the brevity of the summary: it shows where individual claims can be examined in context. The source revision retrieved here is dated Sep 9, 2026. The linked authority identifier is Q7975331. None of the 0 selected statements returned an explicit reference.
Overview language is designed for orientation and should not be treated as a substitute for the evidence cited beneath it. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
How to read it
Use the entry as an orientation point, then follow its citations and revision history. Names, dates and institutional relationships should be checked against the original record.
- Subject orientation
- Search vocabulary
- Locating named sources
The closest primary source, responsible institution and strongest cited specialist reference.
Three-step research path
- Establish the record: confirm the title “Wave shoaling”, its source revision and the description used here.
- Expand the search: follow Wave shoaling primary sources, Wave shoaling archive and Wave research across catalogues and specialist indexes.
- Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.
Questions for further research
- Which source most directly establishes the central claim about “Wave shoaling”?
- Which cited source is closest to the event, object or claim?
- What terminology or title could unlock a more precise catalogue search?
Search terms from this dossier
This entry incorporates text from “Wave shoaling” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.