MANY of you may have seen the Paul Hudson account on TV on 15th Dec talking about the remarkable and rare appearance on the Wharfe at Bolton Abbey of ‘ice pancakes’. I just switched on right at the end, but I guessed what he was talking about because....that very afternoon we ventured from the warmth of the house for some of that fabled and necessary ‘fresh air’. We decided on a short undemanding walk along the riverside. Following the equally necessary hot chocolate at the cafe we happily spotted a kingfisher zooming against the current, a heron standing sentinel beside the cold water and a cloud of goldfinches grazing the hawthorn. We considered our spotting complete. But then noticed, across the river, three or four white discs floating in the river. Why are the Bolton Abbey Estate allowing people to chuck pizza bases in the river, what a mess!

A little further on we realised there were dozens of these discs and realised that weren’t plastic refuse after all and that something much stranger was happening.

These turned out to be Ice Pancakes. But where have they come from? They are not uncommon in Antarctica where they can be up to two meters in diameter. Our local pancakes were a more modest 40cm, with, as you see, baby pancakes about 10-15cm across.

In rivers they are believed to form when foam on the river (which is seen frequently near Bolton Abbey - perhaps a result of the turbulence upstream at the Strid?) begins to freeze. These frozen lumps of foam join together and are sucked into swirling eddies which round off the corners as they bang together.

Back to ice. As well as their satisfying circularity they have a slight rim at the edge (just like the aforementioned pizzas!). This is thought to be created as splashes of water adhere to the edge of the disc, freeze and build up to create a rim. Although they look quite solid from above, if you are intrepid or foolish enough to try and drag one out of the river you will find that it is quite slushy and breaks apart easily.

Back in Addingham the following day we noticed that, just before the weir at Low Mill, there were what I think of as ‘trial pancakes’...as you see they have the circular shape and size but are, as yet, trapped in a larger body of ice.

Another rewarding local walk, you just never know what you will see.

www.wharfedle-nats.org.uk