The natural Navigation: The Right Course, Naturally

It is a pity that I didn’t have a video camera with me to capture the motion in this puddle. The wind was blowing in from the southwest, but the trees that can be seen in the reflection of this puddle were offering some shelter. The half of the puddle nearest the trees was in their lee and receiving little or no wind. The half that was further from the trees was catching a breeze as it dropped down over the trees. The net result was that the muddy bubbles were being corralled into the lee half, where they were also being pushed gently from one side. It set up a gentle, but constant gyre of bubbles in only one half of the puddle. In a very roundabout way, that has some similarities with other lee methods, the dirty bubbles in this puddle are trying to point in the direction…

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Shortest blog, but a good’ un, which way am I facing when I took this picture?

I ran a private course in the South Downs on Saturday for a group of four friends. One of them gave me a great example of using our senses and a little lateral thought to better connect with nature. Rachel lives southwest of Medway power station and said that she could tell when it was going to snow in winter because these were the only times she could smell the power station itself. The colder northeasterly winds bringing snowy weather and local smells with them.

I took this picture a week ago. It shows the lower fair-weather cumulus clouds against the upper cirrus clouds. It is not at all unusual to watch the lower clouds and upper clouds move in different directions and to feel a third wind direction on your face at the same time.

My thanks to Richard, who sent in this picture from a lad’s walking weekend along the Jurassic Coast. He was given a private course as a birthday present and was on the lookout for natural signposts. Wind and trees don’t scream direction a lot louder than this. He also spotted sand blown only over the northeastern edge of a horse training area and found Polaris, but then struggled to see it from the inside of a pub.

The land’s wind shadow can be seen in the smooth water nearest the foreground of this picture of Nutbourne Marshes. This is an effect sailors, particularly dinghy sailors, will be very familiar with. It is the same effect that causes a build up of ice, sand and dust deposits on the lee side of obstacles on land. It is not usually quite as simple as the object getting in the way of the wind though, because of something called Bernoulli’s Law.

It is one of those laws that features a lot in our lives, but gets little credit. It helps chimneys to work properly and aircraft to fly. It causes the wind to accelerate as it travels over a curved surface and then decelerate as it reaches the other side. It probably deserves more credit as it is this effect that allows boats to sail into wind, a completely…

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Two nights ago the strong winds brought an ivy-ravaged sycamore down into our garden, destroying two fences and killing an apple sapling in the process. I spent a few minutes looking over it this morning and found it to be a haven for lichens, there were at least five different types thriving and probably dozens making less of a splash. It was a rare opportunity to see the tops of the trees as they are, without having to scale them. Lichens are very sensitive to air quality so perhaps being thirty feet up was enough to keep them above the heavier pollutants.

One of the keys to navigating with nature is appreciating scale. It is vital that we do not spend too much time focusing too narrowly or widely. In this photograph, taken in the South Downs on Monday, our eyes are naturally led to the fallen tree. It would be very easy to miss both a bigger clue to direction and a smaller one.

The heart of the tree is marginally closer to our side of the tree, which hints that we are south of it, looking north.

If we peer through the undergrowth and bare tree branches we can see that the land falls away to lower country in the distance. The South Downs are a predominantly east/west range of hills and so any time that we can see a long way down into lower land it suggests that we are looking north or south. The hills are also close…

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The rape flowers are coming into bloom over the South Downs, but they don’t all bloom at the same time.

The crop tends to be on a field that will get a good amount of sunlight anyway, often south-facing, but even within the fields there are subtle shade differences. The flowers tend to appear first in the south-facing dips in the land. This is probably because they are getting plenty of sun, but being sheltered from the cooling winds. As a general rule, nature moves faster the warmer things are.

This morning brought with it a nice thick radiation fog, which the sun will probably burn off soon. There is not forecast to be much wind today, but even a breeze deals with radiation fog, usually anything over 12 knots.

No visible sun, no discernible wind, these are the conditions that remind us that the trees reflect their environment over a long period. They act as a giant USB stick of data about thousands of days of sun and wind. All we need to do is tune our senses and look for it. The thin branch in the bottom left of the picture has been curved upwards by the prevailing southwest winds over time.