Unknown Unknowns in the Desert

There are many things that I am excited about discovering in the Sahara and some of these are what Donald Rumsfeld might have called the 'known unknowns'. Another thirty degrees of night sky will be offered up, including such important treats as Canopus, the second brightest star in the sky (after Sirius). It is impossible to see under any conditions from Britain.

Although I must not waste the precious liquid, it is also mouth-watering to try to imagine some of the 'unknown unknowns'. I will be keeping the senses fully alert and hoping to catch the smell of oases on the wind, but perhaps there will be some surprises too. R. A. Bagnold, a desert expert and scientific pioneer, once found a water hole by following the smell of a single camel he picked up from eight miles away. My method of travel makes it very unlikely that I will be able to use this method. I suspect that shortly after setting off I will begin the process of smelling more like a camel than a human being myself.

Changing Winds

During a short outdoor navigation course yesterday, nature once again enjoyed mocking me a little.

While discussing methods of using the wind to navigate, I had explained how wind direction is surprisingly constant over a period of hours and although small shifts are common, large changes are much less so, and complete reversals very rare. The key is understanding that a significant change in wind direction will be caused by a change in the relationship between your location and a nearby weather system, ie. a front moving through. The change in weather is usually gradual enough to foretell of wind shifts, but not always...

Yesterday we witnessed a complete flip, the wind direction shifted almost 180 degrees from south-southwest to north in one hour. This was something that I had just proclaimed to be almost unheard of, unless there was a complete change in weather. The weather had not yet changed, there remained scattered cumulus clouds, which made me uneasy. I came close to volunteering to eat my hat if we did not witness a quite serious weather change shortly, but resisted and just said that it was very likely.

Fortunately, minutes later the sun disappeared, the scattered cumulus clouds merged into a darkening blanket and the rain began to pour. Even cold rainwater trickling down the back of my neck was a better sensation than feeling that nature has a malevolent disregard for any honest attempt to explain it.

Green Tinged Trees

Picking up on a theme I touched on a few days ago, it is remarkable and delightful how differently we all see the world. Yesterday during a short course in the South Downs, we were sitting on a bench with a great view having a drink of water and a snack. It is a bench and view that I have come to know very well, at least I thought I had.

Scale is such a key to reading the land, the ability and conscious decision to zoom in and out, from miles of landscape one minute to the tiniest patch of lichen the next. Maggie who was sat only two feet from me, spotted something in front of us that I had never noticed before. Her eyes were clearly picking up colours more sensitively than mine yesterday as she had picked out some shades of purple in a distant woodland earlier. She drew my attention to the green tinge in the beech trees that dominate this photo. We are looking south, where the land disappears is the sea, and the moist conditions of the north side of these trees must be proving heaven for mosses and lichens.

Sand Dunes and Endurance

I spent this evening studying some well-respected sand dune theory before my upcoming trip to the Libyan Sahara. It had been a long day, with lots of fresh air, and I may have bitten off more than I could chew. Let me share a small excerpt of it with you:

'Confining ourselves to fully developed turbulent flow throughout the fluid, there remains the question of the small-scale flow over and round the individual grains on the surface. This depends on Reynolds' Number of the form V*d/v, where d is the mean surface roughness which is of the order of the grain diameter. It has been found that when V*d/v>3.5 the grain behaves as an isolated obstacle in the path of the fluid, and throws off a chain of eddies from its lee face.'

From 'The Physics of Blown Sand and Desert Dunes' by R.A. Bagnold. 1954.

Great stuff, I'm sure, but enough to make anyone head into the wilderness.

Natural Navigation Frustration

On a family visit to Longleat on Monday there was the perfect illustration of a frustrating problem that has confronted me for over a decade.

Sometimes knowing the direction you want to go is not nearly enough.

Direction is the cornerstone of all navigation, not least natural. Natural navigators are sometimes forced towards a principle of 'if we head towards our destination we will get there, eventually'.The problem lies in that sometimes even if we know the way we want to head it is not possible to go that way and we are forced to make difficult choices and compromises.

The Longleat maze is an extreme analogy of the challenge. Standing on one of the wooden bridges that give a limited overview of the maze structure it was quite easy to see the direction of our goal. The wooden fort in the centre of the maze was southwest of us, but this knowledge is next to useless if you come across a junction that offers routes without any southwest in them, as we of course did repeatedly. At that point you have to resort to instinct / guesswork / sixth sense / reading the mind of the enemy! That is point and the fun in a maze, but...

...sometimes the real world is not much kinder. A pure natural navigation exercise across the rural English landscape to a point only five miles away 'as the crow flies' can take five hours or more, if trespass is avoided. It is rare that a path junction gives you an option in exactly the direction you want to go, and so often when it does it will mock you by deviating wildly a few minutes later. This is the main reason that wilderness, even light shades of it, are so valuable for such pure exercises. Dartmoor poses its own challenges with its low level vegetation and even lower visibility at times, but it is a real treat in allowing a walker to pursue a line of their choice - until they are sucked into a bog at least!

Reading the land can help at times, particularly in hilly or mountainous terrain. The classic example is that it is usually better to follow a six mile curvaceous detour around a horseshoe ridge than to charge down into the steep valley and up the other side for the three mile short cut.

At one level this time issue does not matter very much. If time is really the issue then don't walk, or get out a brace of compasses and GPSs. The heart of the frustration for me is not the time it takes to make the journey, but the time it takes to teach the skill. The best method of teaching is often to say 'off you go', but sadly the pressures of modern life are such that there are few who can afford to take a whole day over a few miles. Sometimes it feels as though there is little room for a slow skill in an instant gratification society. Fortunately for me there are still enough who have not signed up to that philosophy yet, who have not yielded all to convenience and who choose to learn this rare art instead.

The Patience of Stonehenge

The Gooley family spent Sunday afternoon mucking about at Stonehenge and then heating baked beans and pasta on the VW campervan stove. A modern, but not very, ceremony that paid homage to some ancient rituals.

I was perhaps the only tourist walking around the perimeter who was taking note of the varying moss and lichen growth as I worked my way round the stones from the north side through west, south, east and back. It wasn't the subtle shifts in colour that held my thoughts though.

There is surprisingly little that is properly understood about Stonehenge, but some solid deductions are possible. The alignment of the stones confirms a true understanding of solstices by its architects. It is tempting to think that solstices were a widely understood phenomenon even in ancient times and not give this aspect much more thought, but that would be to do a disservice to the Stonehenge people. While it is very easy to understand the principle of the sun's rising and setting moving from a northern to southern extreme from midsummer to midwinter, it is a different matter being able to pinpoint the spot the sun will rise and set on the solstice days from an exact location. The modern observer still uses either sophisticated technology or tables to do this. It did not require any great leap in thought or development of technical ability to do this in ancient times, but it did require considerable patience and dedication.

The erecting of the stones themselves would have taken physical determination (about thirty million hours of it apparently) and some skill, but the correct positioning of them would almost certainly have required observation from a single site over a period of at least a few years. The number of times that the position of rising or setting was obscured by cloud for example cannot be known, but each occasion could potentially have added a year to the project. Given the scale and physical effort behind the endeavour it is unlikely that they would have settled for any approximations.

It is the impressive physical stature of the stones that draws attention, but I find the idea that an ancient society was able to make a big plan and stick to it over many years more fascinating personally, especially since there was no tangible reward for this patience.

Druidmobile

Off to Stonehenge for the day in a VW Campervan. I know.

Currents: Hot and Cold, Old and New

There is one modern view that holds man as master of the natural world, shaping it to meet his needs and desires. There is a conflicting view that we are but specks on the backs of tortoises on the backs of elephants, balanced precariously on floating logs, vulnerable to the slightest quiver of nature's balance. Somewhere at the heart of this debate is the question of whether the human being understands its position in the natural world and is a sensible custodian of its own fortune.

There is much in Peruvian history, natural and political, for both sides to leap on and scrap ferociously with. It might be diverting, if not entertaining, to take a look at a very small slice of it.

Trade winds carry warm water west away from the Peruvian coast and a Humboldt current brings cold nutrient-rich water flowing in to replace it. The birds like this water and thrive and then they leave their droppings. Guano has been a part of Peruvian history since early Inca times. It was used as a fertilizer and as such became an integral part of the empire's wealth. Later it was realised that it could be used as a key ingredient in gunpowder. It was prized for both uses, but we will venture into very hot currents if we dwell on which of the two uses brought more joy.

Like I said at the beginning, there is plenty for both sides to scrap with there. Having lit the blue touchpaper, I think I'll just retire to a safe distance now.

A Tale of Two Tree Stumps

I ran a small private course yesterday and enjoyed a wonderfully ironic moment. It was almost embarrassing.

The first half of the day was spent indoors studying the theory, looking at photographs and playing with celestial models. One of the points I am always keen to make is about the relationship between the uses of our senses and wayfinding. Sight is so often under-rated because its use is so immediately obvious, but we rarely acknowledge how much detail is allowed to escape. For example, we have evolved to identify things by shape much more readily than by colour or shade. Our brains tend to identify an object as a tree, ie. not a threat, and then move on to processing other information without noticing the subtle differences in shades of the leaves at all. Sometimes it pays to rein it in, to force it to focus and to analyse some of the other detail that is coming in through our eyes. It is only by slowing our thoughts that our brains can actually start to see some of the things that our eyes see.

However aware we become of this, some details will always escape our eyes and mind. That is why walking in a group can be so rewarding.

After lunch we set out into the South Downs. A couple of hours into the walk my eyes were drawn to a stout beech stump, its sawn trunk covered in a thick moss felt. Using my fingers and then a stick, I began peeling away the moss. I wanted to reveal the rings of the dead tree and use the position of its heart to indicate direction. Stephen, who was standing a few feet away, politely pointed out that there was a near identical tree stump less than twenty feet away with no moss covering its rings. I had let myself become so drawn into one object that I had lost the wider picture. I walked over to the stump and had a bit of a laugh at myself. I had managed to blind myself to the bigger picture by studying the finer detail. Nature was once again gently mocking and reminding of the need for balance in everything.

That's More Like It

My wife agreed to drop me in a strange part of the South Downs this morning as part of a long-winded school run. The Land Rover was happy again, away from the ice. It will devour giant puddles all day long with a smile.

Lion King Astronavigation

Reading the kids their bedtime story is one of the great escapist tactics. Being transported to worlds filled with Power Rangers and Megazords, or preferably something more 'Winnie-the-Pooh-like' is a pretty good way of switching off for the day.

Occasionally the tactic backfires. When the stories become deeply mythological it can take me closer to one aspect of my work. Last night the Lion King started to get a bit celestial...

Mufasa looked up at the starry sky and said, "The great kings of the past look down on us from those stars. So whenever you feel alone, just remember that those kings will always be there to guide you... and so will I."

The Lost Hecklers

A combination of a low-show on Friday due to bad conditions and the fact that everyone is really getting into the idea of heading off somewhere hot at some point this year gave the Destinations Travel Show a real buzz yesterday.

I gave my talk, 'The Forgotten Journey', on behalf of the Royal Geographical Society. The audience clearly had one or two enthusiasts amongst it as the questions were even more interesting and perceptive than usual.

Some of my family live nearby and had threatened to turn up and heckle at the back. One small problem was that they intially headed to the wrong part of Earls Court and only arrived to hear the second half of the talk. There may be a opportunity for some weekend work there, either for me or some sharp Tom-Tom salesman.

The Generous Trees

The more I study natural navigation, the more indebted I feel to trees. There are few environmental conditions that they do not make some effect to reflect. Sun, rain, shade, heat, cold, dryness, dampness, soil type... and in this case snow and wind.

Early on Monday morning these young beech trees pointed very dependably to NNE with their white lines. I was able to leave the path with confidence.

Ice and Sky

After a long stretch at the desk yesterday I treated myself to a dusk trip up into the Downs in the Land Rover. Leaving the main road along a little known and steep track, the tarmac turned to slush then hard, packed grey and white ice. It is the first time in years that I have come across a situation that my Defender has struggled in. The words of a 4x4 expert I know came to mind, 'Sometimes the number of wheels doesn't matter, if there is no traction, then there is no traction.' I parked, wedged some rocks under the wheels and scrambled up a steep shortcut on all fours.

The rewards were moody fluctuating skies, an angry wind and great views.

The Snow Compass Points North

Sun Patterns and Natural Randomness

Time for a bit of ramble.

At the heart of natural navigation there is potential for conflict.

If the sun did not behave with rational, dependable predictability then reading its effects might be a forlorn cause. We can say with great confidence where it will be in the sky at almost any moment in the future. And yet, nearly everything that follows the sun closely, from plants and animals to the weather itself, does not seem to have much fondness for rigid patterns or predictability.

This photo is an example. I could have worked out exactly the spot that the sun would rise and what it would do during the day years ago if I chose to, it would be a poor bookie who took bets on that sort of thing, but the weather... that is very different. The odds of me being surrounded by deep snow right now, particularly this close to the south coast, must be quite small. The seasonal fluctuations can be further complicated by the fact that we are now getting a lot more solar heat than we were a month ago: we are more than six weeks from the coldest time of the year in pure solar terms.

If we are looking at things that are removed from the skies, but are still strongly influenced by them then we are left with no choice but to look past the randomness, to look for clues in trends. Herein lies the conflict: we observe randomness and regularity in tandem. To resolve this and to have confidence in reading nature we must accept that there is randomness that lies with trends, which in turn rest on predictable patterns.

Accepting randomness, not being fooled by it as we search for sometimes hidden trends, that is where the science goes a bit quiet and the art lies.

The Gloves and the Cocoa

As my head hit the pillow last night I was worried about today. Worried about missing out. The forecasted snow might mean that I should be outdoors, but today was always shaping up to be a very busy day at the desk.
One of our sons solved this little dilemma by getting me up at 4.30am. One peek out the window was enough to bring a childish, almost wild, excitement. For me that is, my son fell straight back to sleep. I was out on the hills by 5.00am. The plan wasn't perfect: in order to avoid waking my wife I had to make do with the kit I could find downstairs.
I ventured out into the cold woods, wearing jeans, wellington boots and a pair of gardening gloves. The Shackleton Centenary Expedition this was not.

The woods managed to be both white and dark simultaeously.

I have just returned from three hours of exhiliration and the sharpest air to a bowl of perfect porridge. There were many treats along the way, some of them navigational, that will find their way to this space in time. Time to chain myself to a desk for several hours.

The fresh air should keep me going for a few hours, but if things slow later today then I will reach for Plan B. It is a plan that is dark and bad. I'm not much of a coffee drinker, but there is some nuclear-strength chocolate in the cupboard. The sort of thing Dr Evil would eat. It's pure cocoa solids by another name and dissolved in hot water should do the trick.