= Tidal range
The <tidal range> is the difference in sea-surface height between a specified high tide and the neighboring low tide, measured relative to the same datum. A high-water level of $4.2\,\mathrm m$ and low-water level of $1.1\,\mathrm m$ give a range of $3.1\,\mathrm m$.
For a sinusoidal tide $\eta(t)=A\cos\omega t$, the range is $2A$, not the <amplitude> $A$. Interference between lunar and solar tidal contributions produces larger spring ranges and smaller neap ranges. Coastline geometry, water depth and resonance modify the local response, so the tidal range cannot be inferred from astronomical forcing alone.
Back to article page
