Welcome to this month’s update from Boscastle National Coastwatch Institution (NCI).
When visiting the harbour or walking along the coast path, have you ever wondered what causes the tides? We have the moon to thank for that. It takes 24 hours and 50 minutes for any point on the earth to rotate from an exact point under the moon to the same point under the moon. When that point is in line with the moon gravitational pull causes a high tide and when perpendicular to the moon a low tide, giving us two high tides and two low tides in just over 24 hours. This slight increase on an earth day of 24 hours pushes the times of the high and low tides a little later every day. It takes about 27 days for the moon to complete an orbit of the earth and when the moon and sun line up with the earth (twice per orbit), their combined gravitational effect produces higher than average high tides and lower than average low tides. These are known as Spring tides and have the greatest tidal range. When the sun and moon are not in line but at right angles (also twice per orbit), the gravitational effect is reduced causing lower than average high tides and higher than average low tides. These are called Neap tides and have the smallest tidal range. If you would like to see this explained by video, click the following link…
This large variety in tide times and heights means it’s a very good idea to check on tidal conditions before embarking on any coastal activity. The daily tide times and weather conditions are posted on the NCI Lookout Station door on the Willapark headland.
Boscastle is famous for its blowhole, an underwater channel that shoots a horizontal jet of water across the harbour whilst emitting a thunderous sound. Best about an hour before and after low tide with a reasonable sea swell. It can be seen below Penally Point, just beyond the last breakwater wall. Did you know the blowhole has a much smaller and less known sibling. We can see this from our lookout and it’s located on the south face of Meachard island, just above the high water line. Meachard is the rock spine shaped island protecting the harbour entry. This blowhole has a much smaller puff of spray, so when you are next walking on the headland, look towards Meachard and see if you can see it.
Finally, thinking of all the wind we’ve been experiencing recently, Boscastle has two weather vanes featuring fish designs. Both can be seen from the NCI Lookout Station, one through our north facing window and one from our door. Whilst enjoying a walk around the harbour or up on the Forrabury Stitches take a moment to see if you can see them. Clue to location in the photos below.
With daylight now getting longer the NCI Lookout operates from 08:00 to 16:00, 7 days a week. In April with the further extension of daylight hours we add an evening watch from 16:00 to 20:00.
