Paddling on exposed coastlines. Not today…

Big swells and storms today in Jersey. Ferries stuck off the east coast of jersey

The effect of the Continental shelf reduces wave height on the edge of the pink

for 6 hours because it was so rough to get into St Helier harbour.

These images show both the size of the waves and also the effect of the coastline/ deep water off Jersey and Guernsey.

Note how the larger swells are largely blocked by the Continental shelf.

There is deep water (60m) near the Hanois light on the South West coast of Guernsey. Hence the much larger waves.

Jersey Mets wave buoy recorded 10m swells.

The South coast of England gets some protection from headlands which reduce the wave heights. The same can be seen off the East coast of Guernsey where there is less swell. In some areas you can spot the

Land gives a bit of protection on the East coast of Guernsey

refraction/bending of the waves around headlands. Note the way the swell is bent around in some locations.

These are extreme examples but we can see similar effects when paddling near headlands or onto a more exposed section of coast.

As the tide rises or falls I often notice changes in swell heights as the deeper water allows larger waves to get nearer the shore.

You can get more amazing data via Previmer. I’ll be writing a bit more about this remarkable site.

Thanks to Colin at Sea kayak Brittany for the link.