The tide is seasonal. Every spring it slinks inland up estuaries and sand flats, climbs up cliffs to its high summertide line, and every autumn it recedes.
There are two bodies that effect the tide, the Moon and the Martyr. The moon is small, with a monthly cycle, and gives waves and minor daily tides. The Martyr is much larger and more infrequent, and causes the more consequential yearly tides. The sun also plays a role in this, I assume. I'm no scientist.
Some terms:
- Maytide/Springtide - when the tide rushes in
- Summertide/Wintertide - the tidal extremes, around the solstices
- Tidepart - when the tide rushes out, also called the Octobering, or less commonly Septembring
- Summerport - a city’s high-water port
- Winterport - a city’s low-water port, often submerged half the year
Powerful currents peak each equinox as water surges in or out of harbors and bays. October currents are especially dangerous, sending boats ripping out to sea, and Maytides are said to bring good fortune.
Some regions, especially inland seas like the Cauldron, are reletively untouched by the high tide, while other coasts, like soft Ossea, are drastically changed. Lake Sometimes, for example, is a lake only half of the year.
This high tidal range leads to the prevalence of binary towns; for instance Telemet Summerport and Telemet Winterport on The Isle Othlethin. One serves the inland shore, and one lies below the surface, waiting for winter. Folk use coffers called winterchests to store valuables, which are boxes sealed on every side but the bottom, with legs holding them up and little shelves within, and which work like diving bells to keep their contents dry. Some even build winterport houses with watertight roofs, to keep the sea without and provide a safe, dry pocket of air for all their goods.
The consistent uniform nature of the tide around Yon implies a reverse, a place where the water goes in winter and comes from in the spring. There are tales of a land such as this, although it hasn't has been found by those that would tell of it. Common phrases denoting faraway, strange places:
- where the autumntide goes
- what floats in winter
- where summer sees no sea
- where the sea swells in winter
The tide is more unpredictable and adheres less to the seasons on outer isles. The Far West and the Far South, for example, experience strange tides, sometimes lasting days or weeks, sometimes several years.
Octobering
Some see autumn as a time to leave and seek new places. This, like the currents themselves, is called Octobering. Some intend to return, many do not. A sign on a shop window, maybe: gone Octobering, back in spring.
Extreme examples of Octobering:
- The hunting of the Zigglewomp.
- The flight of the people of Edya across Elbalad to Ealdor's Rest.
- The yearly migration of the Rhingdar across the great tidal plain of Alal.
- The Baron of Inselberg's attempt to return to his namesake town.