20 March 2016

Stromness Piers 20/03/16 9:10

Stromness piers looking north-east from the Lighthouse Board pier, 9:10am

We start with a line: the line where the sea ends and the land begins in our home town Stromness, Orkney, Scotland. This is the line of the solid stone-built piers and jetties which characterise the town’s seafront, a legacy of Stromness’s maritime past. Each pier is as unique as the old merchants’ houses they project from, built in piecemeal fashion as the town developed over the last 300 years.

Despite its apparent permanence, this line is permeable, mutable and seasonal. Each day the drystone piers absorb, then release, the incoming and outgoing tides. They might be overtopped by spring tides* with south-easterly surges, whilst the stonework is deteriorating in frequent winter storms. In summer, tourists are drawn to their old world charm. This line might not have really changed in the last 150 years, but the town has certainly changed around it.

A town above the piers

It is fitting that our first post falls on the Vernal Equinox – the start of astronomical spring. From this point forward, the hours of daylight grow, as the hours of night decrease, a change which is particularly marked at our 59° latitude. In parallel with the fluctuations of daylight, moon phase, and tide over the next year we will follow the Stromness piers and document the human and non-human interactions with and around them.

Sunrise            06:16                                           Moonrise        15:13

Sunset             18:24                                           Moonset          05:18

Low tide          01:11 (1.19m)                            Low tide          13:36 (0.81m)

High tide         07:29 (3.13m)                            High tide         19:55 (3.07m)

Waxing Gibbous                                                Spring Tide 23 March

* The size of the tide runs on a two-weekly cycle and is related to the phase of the moon. Spring tides occur in and around full and new moons and are when the difference between the high and low tides is the greatest, neap tides occur in a fortnightly cycle opposed to springs and are when the difference is the least. The gravitational force created by the rotation of the earth also affects the tides, and as the earth is an ellipse rather than a true sphere, this is not constant. During the equinoxes, the earth and moon are closer together than at other times in the year, and so the gravitational pull, and the related tides, are greatest at these times.

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